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The Star-Planet Activity Research CubeSat (SPARCS) is positioned to revolutionize our understanding of M-dwarf star evolution, activity, variability, and the habitability of surrounding exoplanets. SPARCS will be the first mission to observe M stars for long periods of time simultaneously using a dual channel FUV (153 – 171 nm) and NUV (260 - 300 nm) imaging system. Anticipated to launch in 2023, SPARCS will provide key UV context to future observations by TESS and JWST, and the spaceflight application of advanced new detector technologies will pave the way for their implementation into future missions like LUVOIR and HabEx. To realize the scientific potential of SPARCS against the challenges of the ultraviolet spectrum, we are developing the specialized facilities, procedures, and tests necessary to assemble, integrate, and test the SPARCS science payload and spacecraft. A thorough testing campaign will verify the performance of individual payload components and obtain calibration baselines from the fully assembled science instrument that are vital to the data reduction process and in-flight contamination monitoring. SPARCS requires extensive contamination control to maintain its sensitivity in the FUV and NUV, which means all of AIT must occur in controlled and precisely monitored environments. This work will result in: (1) The delivery of the assembled and tested SPARCS spacecraft for launch in 2023. (2) A comprehensive performance validation and calibration baseline for SPARCS including a measurement of system throughput to for every wavelength across the SPARCS bandpasses, maps of NUV and FUV sensitivity across the payload field of view, and a full set of calibration products like flatfield images and dark current measurements for data reduction and comparison with calibration products acquired in orbit to monitor spacecraft conditions. (3) The establishment of a fully operational CubeSat AIT laboratory at ASU equipped to handle CubeSats up to 6U in size requiring meticulous contamination control up to the levels required for working in the FUV. This paper presents the work completed so far on the development and early operation of assembly, integration, and testing facilities for SPARCS. A custom thermal vacuum (TVAC) chamber facility was created and one of Arizona State University’s cleanroom environments was retrofitted to accommodate a 6U ultraviolet CubeSat requiring strict contamination control. We will describe the TVAC facility design and early testing, the cleanroom operation and contamination monitoring, and the development of an optical system and procedures to characterize the optical performance.

We have developed a novel in-line solution for the characterization and metrology of high-aspect ratio (HAR) semiconductor structures using transmission small-angle X-ray scattering (SAXS). The solution consists of the Sirius-XCD® tool, NanoDiffract for XCD (NDX) analysis software and high-performance computing infrastructure. The solution provides quantitative information on the orientation and shape of HAR structures, such as 3D NAND channel holes and DRAM capacitors, and can be used for development and control of the critical etch processes used in the formation of such structures. The tool has been designed to minimize expensive cleanroom space without sacrificing performance with typical measurements taking only a few minutes per site. The analysis is done using real-time regression in parallel to the measurements to maximize the throughput of the solution. We will illustrate the key features of the solution using data from a HAR reference wafer and provide results for hole shape and tilt across the wafer together with complimentary data from other techniques. We will also discuss future opportunities for both stand-alone XCD applications and possibilities of XCD-OCD synergies including hybrid metrology in solving complex high-aspect ratio (HAR) and other applications.

The X-ray parallel beam facility XPBF 2.0 in the laboratory of the Physikalisch-Technische Bundesanstalt at the synchrotron radiation facility BESSY II provides a parallel beam of very low divergence, and adjustable beam sizes between about 100 μm and at least 5 mm. Further, XPBF 2.0 is equipped with a vacuum chamber with a hexapod system for accurate positioning of all silicon pore optic (SPO) sizes to be investigated, and a vertically movable CCD-based camera system to register the direct and the reflected beam at a sample to CCD distance of 12 m corresponding to the envisaged focal length of ATHENA (Advanced Telescope for High ENergy Astrophysics). Since its installation in 2016, the beamline has been constantly upgraded to improve performance and implementing the changing requirements. To accurately and constantly measure the 12 m distance, between the center of the sample (i.e. mirror module) and the CCD detector, a laser-tracker has been installed. Additionally, the cleanroom, housing the vacuum chamber, was upgraded with a cooling unit keeping the temperature at 20°C. The original phosphor screen in front of the CCD has been replaced with a new phosphor screen with different grain size and material. The next upgrade of the XPBF 2.0 is the installation of a new monochromator mirror to operate the beamline at 1.0 keV instead of 1.6 keV. This paper will present the upgrades of the X-ray parallel beam facility XPBF 2.0 and discuss next steps for characterizing SPOs with synchrotron radiation.

Newly developed space instruments are increasingly efficient and accurate. One of the main drawbacks is that they are consequently more and more sensitive to contamination. Once integrated, optics are continuously exposed to cleanroom environment. Most of the time, cleaning operations are risky or even impossible considering coatings fragility or accessibility constraints. Thus even in cleanrooms, with the use of specific covers and/or the implementation of purging, inducing altogether stringent operational constraints, molecular and particulate contamination deposition appears to be unavoidable. Hence, the use of a protection film on the most critical optics during manufacturing assembly and tests would allow a significant reduction of the overall contamination levels or the release of the operational constraints to reach the same cleanliness target. This study presents the results obtained in the frame of a test campaign aiming at identifying and evaluating the most promising protection films (including varnishes, adhesive tapes and electrostatic films) dedicated to space instruments optics. Impacts on both molecular and particulate contamination were investigated together with associated effects on protected substrates (aspect, spectral properties, …). The best solution has been qualified at Airbus and is currently implemented on flight hardware.

For system contamination control often cleanrooms or clean zones are used. Cleanrooms are classified for particles between ≥ 0.1 μm and ≥ 5 μm according to the ISO 14644-1:2015 classification table. In many applications air cleanliness for larger particles is more important. Especially in optical systems contamination by particles ≥ 20 μm is important. The present ISO 14644 cleanroom standards do not offer methods of controlling and monitoring of these particles. The new ISO 14644-17, of which the Draft International Standard is published in January 2020, covers the missing aspects of air cleanliness for macro-particles from ≥ 5 μm to ≥ 500 μm. The particle deposition rate gives a direct relation between air cleanliness and contamination risk. Particle deposition rate data predicts the contamination by particles during exposure, but the data also provides information on how to reduce the particle deposition rate if required. This paper discusses the specification and application of the particle deposition rate in clean controlled environments. As examples the production of a photo conductor and the assembly of a MEMS inkjet device is described.

For generations lithographers have worked to overcome the difficulties associated with defect mitigation, and since EUV lithography has become mature enough for HVM this concern is warranting ever increasing attention to make such processes profitable. Even though much of the EUV defect effort is focused on stochastic defects, in this work we attempt to assess and understand process defects associated with the interaction between different films in an EUV stack. By understanding the behavior of specific underlayer materials and their chemistry within a given environment we have attempted to tune the surface energies to match the photoresist in the stack. With the correct process changes being applied, we have then worked to correlate the proper matching of surface energies with process defects. The current focus of our work is specifically line collapse, and we believe that developing a fuller understanding of the film interactions will ultimately lead to a more robust EUV process for HVM. We hereby present our work utilizing the SCREEN DUO coat develop track system with an ASML NXE:3300 in the imec Leuven cleanroom facility.

With EUV lithography inserted into the semiconductor production the characterization and control of critical components like blanks, masks, pellicles, optical elements, thin film windows and photoresist is required. Needed for the supply and process chains are on one hand “traditional”, e.g. mechanical, thermal or chemical tests with extended capabilities as well as “actinic” ones, which are directly linked to the interaction of EUV radiation with the sample. Actinic tests are needed to • measure optical properties in the spectral range which is relevant when the components are used, like reflectance, transmission, scatter • determine or apply modifications of material when irradiated with EUV, e. g. resist exposures, degradation tests for components • find or inspect defects and structures on optical components used in EUVL • Mimic processes in the EUV scanner for off-line optimization. For such actinic qualification in the individual industrial or research lab with 13.5 nm radiation only few metrology tools are readily available off-the-shelf. The industrial infrastructure for EUVL lab tools suffer from the fact that most of such tools are such specialized that only – at best – few of a kind are needed in the world, which does not deserve a classical product development. This analysis has driven our strategy for supporting our customers mainly with tailored “one of a kind” solutions, while still reaching product like reliability by frequent reusing of already existing building blocks, tested subunits and components and general approaches and architectures. The basis of this approach is on one hand our experience to serve our customers from “big science” worldwide with RI-engineered research installations since more than 30 year. On the other hand our EUV application experience is based on a broad source portfolio with stand-alone DPP and LPP sources for XUV together with an established supply chain in advanced EUV optics, detectors and spectral filtering. This allows us to use long experience in design, machining and assembly of ultra-clean components in ultra-high vacuum and cleanroom applications, including ultra-clean sample handling, loading and manipulation. Our stand-alone tools offer fully automated, fail safe electronic control including custom tailored data evaluation and reporting solutions. With the special demand from each new project, we are consolidating and expanding the knowledge base. Examples of such actinic tools for the EUVL infrastructure will be presented, as e.g. spectral reflectometers, full area inband EUV property mapping, EUV pellicle transmission and reflectance tools, microscope, defect inspection, nano-printing tools and sensitivity calibrated stand-alone resist exposers.

The Optical Payload System (OPSys) is an INAF (italian National Institute for Astrophysics) facility hosted by Aerospace Logistics Technology Engineering Company (ALTEC SpA) in Turin, Italy. The facility is composed by three clean rooms having different cleanliness levels, a thermo-vacuum chamber (SPOCC, Space Optics calibration Chamber) with a motorized optical bench and several light sources covering the range from the extreme ultraviolet to the red light wavelengths. The SPOCC has been designed having in mind the very stringent requirements of the calibration of solar coronagraphs and the suppression of the stray-light. The facility and the optical performances will be described here. The calibration campaign performed on Metis space coronagraph will be reported as a case study.

We will discuss laboratory experiments in silicon-photonics developed for senior and graduate level students. The learning objectives for this laboratory includes basic microfabrication techniques in cleanroom, understanding design and process flow, fabrication and testing of silicon waveguides and Mach-Zehnder interferometers on a silicon-on-insulator (SOI) wafer. We will also discuss a typical team project outcomes and examples of experimental work and report by student group. Additionally, we will comment on student’s learning and skill set acquired through this introductory hands-on project-based silicon photonics class.

While there is great interest in 3D printing for microfluidic device fabrication, the challenge has been to achieve feature sizes that are in the truly microfluidic regime (

The laser damage thresholds of optical coatings can degrade over time due to a variety of factors, including contamination and aging. Optical coatings deposited using electron beam evaporation are particularly susceptible to degradation due to their porous structure. In a previous study, the laser damage thresholds of optical coatings were reduced by roughly a factor of two from 2013 to 2017. The coatings in question were high reflectors for 1054 nm that contained SiO2 and HfO2 and/or TiO2 layers, and they were stored in sealed PETG containers in a class 100 cleanroom with temperature control. At the time, it was not certain whether contamination or thin film aging effects were responsible for the reduced laser damage thresholds. Therefore, to better understand the role of contamination, the coatings were recleaned and the laser damage thresholds were measured again in 2018. The results indicate that contamination played the most dominant role in reducing the laser damage thresholds of these optical coatings, even though they were stored in an environment that was presumed to be clean.

The kinetics of molecular transport of contaminant species is highly dependent on the distribution of desorption activation energies. Accurate measurements of these kinetics are essential to improving confidence in molecular transport modeling and setting appropriate beginning of life (BOL) cleanliness requirements. We present results that combine laboratory experiments with computer simulations to determine the distribution of effective activation energies for outgassing species from a urethane paint system and non-volatile residue (NVR) collected from an ISO Class 5 cleanroom contamination monitoring plate. Outgassing from samples of primer overcoated with urethane paint were analyzed with the temperature controlled quartz crystal microbalance thermogravimetric analysis (QTGA) technique during the final stages of vacuum baking; cleanroom NVR was also analyzed via QTGA. A computer model was developed to simulate the QTGA results. Data from the experimental QTGA were compared to the simulated QTGA to obtain a distribution of desorption activation energies for contaminant species. The interior of the Ozone Mapping and Profiler Suite (OMPS) science instrument is primed and painted with polyurethane/epoxy material. The distribution of activation energies derived in this study was incorporated in the molecular transport model of the OMPS science instrument, on the Suomi National Polar-Orbiting Partnership Satellite, yielding results that are consistent with the on-orbit optical performance data.

This is an introductory course in silicon photonics for senior and graduate students. Topics covered in this course include: basic properties of silicon waveguides; the essentials of SOI waveguide fabrication; dispersion and propagation loss in Si waveguides; analysis and design of various passive silicon devices; modeling and characterization of silicon modulators; integrated photonic circuit; and layouts for E-beam lithography. This course also includes a laboratory to enhance student’s learning. Students fabricate a thermo-optic MZI modulator in the cleanroom and then characterize its performance. We will discuss experimental work by student groups and comment on student’s learning in this class.

In order to accommodate new instrumentation arriving in early 2018, the Canada-France-Hawaii Telescope (CFHT) converted one of its coude spectrograph rooms into a cleanroom. The new instrumentation required ISO 8 conditions with a desired performance of ISO 7. The turn-key solutions available all provide much higher levels of performance at prices well outside the budget of the project, so we modified the room using a more cost effective in-house approach. We discuss the requirements of the new instrumentation, new administrative rules and procedures, changes made to the room and new equipment, and the resulting performance.

At the German Aerospace Center in Stuttgart a laser damage test bench is run to evaluate damage thresholds of various optical components. The system setup is based on the current ISO standards 11254 for single shot and multiple pulse operation. The laser damage test bench contains two repetitively pulsed laser sources, a Ti:Sapphire and a Nd:YAG laser, operating at wavelengths of 775 nm and 1064 nm, respectively. Harmonic wavelength converters to the visible spectral range are available. Both lasers are supplying the same damage testing rig. Online damage assessment techniques like sensitive scatter probe monitoring and video microscopy monitoring are used. The system is suited and has been tested extensively in the past for dielectric coated optics like beam turning mirrors, reflectors and windows, nonlinear optical components, semiconductors, and laser crystals. The damage test bench is located in a class 10,000 cleanroom environment under a laminar flowbox providing an additional isolation factor of >10^3. The tests can also be performed in sealed optical compartments in partial vacuum and under long term irradiation conditions. All experiments are supported by theoretical simulation of laser-material interactions, down to the sub-ps timescale.

A new metrology and assembly facility was constructed at CNPEM and turned recently into operation. The facility includes an assembly area of 100 m 2 , a high-precision mechanical metrology laboratory and an optical metrology laboratory (OML), both of 50 m 2 , and provide improved environmental and instrumental conditions. All three laboratories sit on inertial blocks with special foundations originally developed and tested as prototype for the SIRIUS tunnel floor. The inertial blocks perform very well in attenuation of external vibrations. The OML is cleanroom ISO7 and has temperature stability better than ±0.1 K. Measurements of the surface under test (SUT) using NOM, Fizeau- Interferometer (FI), Micro-Interferometer (MI) and AFM as the four instruments inside the OML cover the full required range of spatial frequencies. We report on the performance of the NOM and FI, the first instruments installed in the OML.

In the near future, robots and humans will share the same environment and perform tasks cooperatively. For intuitive, safe, and reliable physical human-robot interaction (pHRI), sensorized robot skins for tactile measurements of contact are necessary. In a previous study, we presented skins consisting of strain gauge arrays encased in silicone encapsulants. Although these structures could measure normal forces applied directly onto the sensing elements, they also exhibited blind spots and response asymmetry to certain loading patterns. This study presents a parametric investigation of piezoresistive polymeric strain gauge that exhibits a symmetric omniaxial response thanks to its novel star-shaped structure. This strain gauge relies on the use of gold micro-patterned star-shaped structures with a thin layer of PEDOT:PSS which is a flexible polymer with piezoresistive properties. In this paper, the sensor is first modeled and comprehensively analyzed in the finite-element simulation environment COMSOL. Simulations include stress-strain loading for a variety of structure parameters such as gauge lengths, widths, and spacing, as well as multiple load locations relative to the gauge. Subsequently, sensors with optimized configurations obtained through simulations were fabricated using cleanroom photolithographic and spin-coating processes, and then experimentally tested. Results show a trend-wise agreement between experiments and simulations.

Silver coatings are highly conductive functional layers. There are many different ways to product the silver coating but most of them need vacuum or high temperature. Spray coating is a technique that is free of this disadvantages – it doesn't need a cleanroom or high temperature. What's more the layer thickness is about 10 μm. In this article the spray coating process of silver nanolayer is described. Four different inks were tested and measured. The layer resistance was measured and show as a graph. After the layer resistance was measured the adhesion test was performed. The pull-off test was performed on testing machine with special self made module. To conclude the article include the test and measurements of spray coated nanosilver functional layers. The layers was examined for the current conductivity and adhesion force.

Mars Organic Molecule Analyzer (MOMA) is an instrument suite on the European Space Agency (ESA) ExoMars 2020 Rover, and the Mass Spectrometer (MOMA-MS) is being built at Goddard Space Flight Center (GSFC). MOMA-MS is a life-detection instrument and thus falls in the most stringent category of Planetary Protection (PP) biological cleanliness requirements. Less than 0.03 spore/m2 are allowed in the instrument sample path. In order to meet these PP requirements, MOMA-MS must be built and maintained in a low bioburden environment. The MOMA-MS project at GSFC maintains three clean rooms with varying levels of bioburden control. The Aseptic Assembly Clean room has the highest level of control, applying three different bioburden reducing methods: 70% Isopropyl Alcohol (IPA), 7.5% Hydrogen Peroxide, and Ultra-Violet C (UVC) light. The three methods are used in rotation and each kills microorganisms by a different mechanism, reducing the likelihood of microorganisms developing resistance to all three. The Integration and Mars Chamber Clean rooms use less biocidal cleaning, with the option to deploy extra techniques as necessary. To support the monitoring of clean rooms and verification that MOMA-MS hardware meets PP requirements, a new Planetary Protection lab was established that currently has the capabilities of standard growth assays for spore or vegetative bacteria, rapid bioburden analysis that detects Adenosine Triphosphate (ATP), plus autoclave and Dry Heat microbial Reduction (DHMR) verification. The clean rooms are monitored for vegetative microorganisms and by rapid ATP assay, and a clear difference in bioburden is observed between the aseptic and other clean room.

Two new design concepts for all-polymer-based integrated optical Mach-Zehnder interferometers in foil as chemical or bio-chemical sensors are presented. Fabricated with hot-embossing and printing techniques, these all polymer optical components are designed for low-cost fabrication and yield highly sensitive response to external refractive index changes. Compared to traditional semiconductor based systems, these polymer sensors do not need the interaction window and do not require a cleanroom for fabrication. The optical response of the asymmetric interferometers to temperature variations is determined theoretically and compared for two designs. Using the designed asymmetric interferometer, a chemical micro-fluidic test system with temperature controller experimentally demonstrates the sensors’ temperature characteristics.

EUV lithography (EUVL) is well known to be a strong candidate for next generation, single exposure sub-30nm halfpitch lithography.[1] Furthermore, high-NA EUV exposure tool(s) released two years ago gave a strong impression by finer pattern results. On the other hand, it seems that the coat-develop track process remains very similar and in many aspects returns to KrF or ArF dry process fundamentals, but in practice a 26-32nm pitch patterning coat develop track process also has challenges with EUV resists. As access to EUV lithography exposures has become more readily available over the last five (5) years, several challenges and accomplishments in the track process have been reported, such as the improvement of ultra-thin film coating, CD uniformity, defectivity, line width roughness (LWR), and so on.[2-8] The coat-develop track process has evolved along with novel materials and metrology capability. Line width roughness (LWR) control and defect reduction are demonstrated utilizing the SOKUDO DUO coat-develop track system with ASML NXE:3100 and NXE:3300 exposures in the IMEC (Leuven, Belgium) cleanroom environment. Additionally, we will show the latest lithographic results obtained by novel processing approaches in the EUV coat develop track system.

Airborne molecular contaminations (AMCs) have been recognized as a major problem in semiconductor fabrication. Enormous technical and financial efforts are made to remove or at least reduce these contaminations in production environments to increase yield and process stability. It can be shown that AMCs from various sources in laser devices have a negative impact on quality and lifetime of lasers and optical systems. Outgassing of organic compounds, especially condensable compounds were identified as the main source for deterioration of optics. These compounds can lead to hazing on surfaces of optics, degradation of coating, reducing the signal transmission or the laser signal itself and can enhance the probability of laser failure and damage. Sources of organic outgassing can be molding materials, resins, seals, circuit boards, cable insulation, coatings, paints and others. Critical compounds are siloxanes, aromatic amines and high boiling aromatic hydrocarbons like phthalates which are used as softeners in plastic materials. Nowadays all sensitive assembly steps are performed in controlled cleanroom environments to reduce risks of contamination. We will demonstrate a high efficient air filter concept to remove AMCs for production environments with special AMC filters and methods for the qualification and monitoring of these environments. Additionally, we show modern techniques and examples for the pre-qualification of materials. For assembled components, we provide sampling concepts for a routine measurement for process, component and product qualification. A careful selection of previously tested and certified materials and components is essential to guarantee the quality of lasers and optical devices.

Optical system performances can be affected by local optical turbulence created by its surrounding environment (telescope dome, clean room, atmospheric surface layer). We present our new instrument INTENSE (INdoor TurbulENce SEnsor) dedicated to this local optical turbulence characterization. INTENSE consists of using several parallel laser beams separated by non-redundant baselines between 0.05 and 2.5m and measuring Angle-of-Arrival fluctuations from spots displacements on a CCD. We present detailed characterization of instrumental noise and first results for the characterization of the turbulence inside clean rooms for optical testing and integration.

Monitoring airborne molecular contamination (AMC) at the parts per trillion (ppt) level in cleanroom environments, scanner applications and compressed gas lines is essential for processes, equipment and yield-control. For the operation of EUV tools, in particular, volatile organic contamination is known to have as much impact as condensable organic compounds, which requires a suitable sampling and measurement methodology. Some of the current industry standards use sample traps comprised of porous 2,6-diphenylene-oxide polymer resin, such as Tenax®, for measuring volatile organic ( 6 C atoms, about toluene and higher) AMC. Inherent problems associated with these traps are a number of artifacts and chemical reactions that reduce accuracy of reported organic AMC concentrations. The break-down of the polymeric material forms false positive artifacts when used in the presence of reactive gases, such as nitrous acid and ozone, which attack and degrade the polymer to form detectable AMC. Most importantly, these traps have poor capture efficiency for volatile organic compounds (VOC). To address the disadvantages of polymer-based sample traps, we developed a method based on carbonaceous, multi-layered adsorbent traps to replace the 2,6-diphenylene-oxide polymer resin sample trap type. Along with the new trap’s ability to retain volatile organics, the trap was found to provide artifact-free results. With industry trends towards detecting more contaminants while continuously reducing required reporting limits for those compounds, artifact-free and accurate detection of AMC is needed at the parts per quadrillion (ppq) level. The proposed, multi-layered trap substantially increases laboratory productivity and reduces cost by eliminating the need to analyze condensable and volatile organic compounds in two separate methods. In our studies, even some organic compounds with six C-atoms, that are part of exposure tool OEM requirements, were not effectively retained by polymeric traps, but were fully retained on the multi-layered adsorbent trap. This demonstrates that the standard trap used in the industry will result in significantly underreporting actual AMC concentrations for volatile organic compounds, including some siloxanes (TMS, HMDSO, D3). Performance of the proposed trap was excellent at both zero and 50% relative humidity, an important metric, as the trap is used for AMC detection in dry supply gases and humidified environments. Retention of all organic compounds was quantitative for more than 30 liters of air, sufficient for ppq-level detection limits. Desorption efficiency was 94% for C26 compounds. Pressure drop through the new trap was comparable to that of polymer-based traps and much lower than other, commercially available carbonaceous traps. Precision of repeated analyses was 5%, a very good result. Resolution of IPA and acetone was complete and that of a mix of halogenated refrigerants was much improved over existing methods. We propose to adopt this methodology as a new industry standard to overcome widespread inaccuracy in the reporting of volatile organic AMC and false positive condensable AMC.

Contamination-sensitive space flight hardware is typically built in cleanroom facilities in order to protect the hardware from particle contamination. Forest wildfires near the facilities greatly increase the number of particles and amount of vapors in the ambient outside air. Reasonable questions arise as to whether typical cleanroom facilities can adequately protect the hardware from these adverse environmental conditions. On Monday September 6, 2010 (Labor Day Holiday), a large wildfire ignited near the Boulder, Colorado Campus of Ball Aerospace. The fire was approximately 6 miles from the Boulder City limits. Smoke levels from the fire stayed very high in Boulder for the majority of the week after the fire began. Cleanroom operations were halted temporarily on contamination sensitive hardware, until particulate and non-volatile residue (NVR) sampling could be performed. Immediate monitoring showed little, if any effect on the cleanroom facilities, so programs were allowed to resume work while monitoring continued for several days and beyond in some cases. Little, if any, effect was ever noticed in the monitoring performed.

The Dark Energy Camera (DECam) has been installed on the V. M. Blanco telescope at Cerro Tololo Inter-American Observatory in Chile. This major upgrade to the facility has required numerous modifications to the telescope and improvements in observatory infrastructure. The telescope prime focus assembly has been entirely replaced, and the f/8 secondary change procedure radically changed. The heavier instrument means that telescope balance has been significantly modified. The telescope control system has been upgraded. NOAO has established a data transport system to efficiently move DECam's output to the NCSA for processing. The observatory has integrated the DECam highpressure, two-phase cryogenic cooling system into its operations and converted the Coude room into an environmentally-controlled instrument handling facility incorporating a high quality cleanroom. New procedures to ensure the safety of personnel and equipment have been introduced.

Calibration of optical systems is a fundamental step in the development of a space instrumentation. We have built a new cleanroom environment, divided in different areas characterized by a different level of contamination control. A vacuum chamber (a tube of 80 cm diameter, and 2 m length), able to accommodate optical components as well as whole instruments, is interfaced with a ISO6 area, allowing the handling of the instrumentation in a clean environment. The vacuum system is dimensioned to reach 10-7 mbar pressure in the chamber. Inside, a two axis platform allows the rotation of the instrument with respect to the incident collimating beam, in order to test the response of the instrument to light coming from different points of the field of view. A monochromator coupled with different sources provides radiation in the 40-350 nm spectral range, while a parabolic mirror is used as a collimator. As source, different spectral lamps can be used to generate emission lines, while a Xe lamp can be used to have continuum spectrum. An high brilliant hollow cathode lamp has been fabricated by the group to generate extreme ultraviolet radiation. Different calibrated detectors and other completing optical components are available. © 2012 SPIE.

High efficient mask logistics as well as safe and high quality mask storage are essential requirements within an advanced lithography area of a modern logic waferfab. Fast operational availability of the required masks at the exposure tool with excellent mask condition requires a safe mask handling, safeguarding of high mask quality over the whole mask usage time without any quality degradation and an intelligent mask logistics. One big challenge is the prevention of haze on high advanced phase shift masks used in a high volume production line for some thousands of 248nm or 193nm exposures. In 2008 Infineon Dresden qualified a customer specific developed semi-bare mask storage system from DMSDynamic Micro Systems in combination with a high advanced mask handling and an interconnected complex logistic system. This high-capacity mask storage system DMS M1900.22 for more than 3000 masks with fully automated mask and box handling as well as full-blown XCDA purge has been developed and adapted to the Infineon Lithotoollandscape using Nikon and SMIF reticle cases. Advanced features for ESD safety and mask security, mask tracking via RFID and interactions with the exposure tools were developed and implemented. The stocker is remote controlled by the iCADA-RSM system, ordering of the requested mask directly from the affected exposure tool allows fast access. This paper discusses the advantages and challenges for this approach as well as the practical experience gained during the implementation of the new system which improves the fab performance with respect to mask quality, security and throughput. Especially the realization of an extremely low and stable humidity level in addition with a well controlled air flow at each mask surface, preventing masks from haze degradation and particle contamination, turns out to be a notable technical achievement. The longterm stability of haze critical masks has been improved significantly. Relevant environmental parameters like temperature, humidity, AMC (Airborne Molecular Contamination) and particles are controlled online within the system and monitored via the Cleanroom Monitoring System and iCADA RSM. The storage system is well conditioned, based on a fine adjusted heating and cooling concept whereby the desired temperature and humidity values are kept very stable even under high frequent mask transactions. The in-house developed RFID system and traceability of masks within the Infineon Dresden Lithotool landscape is a new and complex logistics improvement, decoupling masks from boxes, saving costs and time and reducing particles. The presented hardware and software solution shows how the potential of automation and improved production efficiency can be increased by such adapted systems even in a mature 200mm waferfab.

Current state-of-the-art commercial sensors and actuators do not meet many of NASA s next generation spacecraft and instrument needs. Nor do they satisfy the DoD needs for satellite missions, especially micro/nano satellite missions. In an effort to develop advanced optical devices and instruments that meet mission requirements, NASA Langley recently completed construction of a new cleanroom housing equipment capable of fabricating high performance active optic and adaptive optic technologies including deformable mirrors, reconfigurable lenses (both refractive and diffractive), spectrometers, spectro-polarimeters, tunable filters and many other active optic devices. In addition to performance, these advanced optic technologies offer advantages in speed, size, weight, power consumption, and radiation tolerance. The active optic devices described in this paper rely on birefringent liquid crystal materials to alter either the phase or the polarization of the incoming light. Design considerations and performance evaluation results for various NASA applications are presented. Applications presented will include large space telescopes, optical communications, spacecraft windows, coronagraphs, and star trackers. Keywords: Photonics, Adaptive Optics, Tunable Filters, MEMs., MOEMs, Coronagraph, Star Tracker

Airborne molecular contamination (AMC) assessment approaches can vary greatly between different fabs and even between different divisions within a given company. Some companies have very rigorous testing schedules (such as those needed to maintain tool warranties) while others feel AMC testing is only necessary when they are having a problem. While choosing to only test for AMC when a trouble arises may be cost effective in the short term it can have significant impacts on tools, in particular tool optics, and product losses due to defects which can cost significantly more in the long term than the AMC testing would have. Another critical issue in assessing AMC is what species you should be testing for. Some volatile species may not cause an issue in your process while part-per-trillion volume (pptv) amounts of others can do serious damage to your tools and/or products. Knowledge of which volatile compounds can cause problems in your applications and at what levels is crucial in deciding what type of AMC assessment to perform and at what frequency. Typically four classes of AMC are routinely monitored in clean rooms and tool environments: acids, bases, hydrocarbons, and refractory compounds. Real world examples will be presented using the solely solid-state trap collection methods utilized by SAES Pure Gas.

Cleanroom technology is a principle pre-condition and the enabling technology for contamination free manufacturing. With the transition from large cleanroom facilities for semiconductor manufacturing to localized encapsulated cleanroom solutions which are called minienvironments the traditional cleanroom technology is extended into a new field of applications. With view to the highest requirements in semiconductor industries and especially in the mask area, extraordinary concepts and solutions has to be developed and applied. In this contribution the fundamental considerations about the different concepts for minienvironments are outlined and reviewed. A set of various parameters involved in a design process for a state of the art minienvironment are given and discussed in detail. The resulting different concepts are presented and the strength of each concept is discussed. The resulting minienvironment solutions are demonstrated on three characteristic examples and options, alternatives and the advantages of the individual concepts are mentioned. Based on the current status of minienvironment technology an out-look is given about future challenges and open questions to be solved.

The Large Optical Test and Integration Site (LOTIS) at the Lockheed Martin Space Systems Company in Sunnyvale, CA, has successfully reached Initial Operational Capability (IOC). LOTIS is designed for the verification and testing of optical systems. The facility consists of a large, temperature stabilized vacuum chamber that also functions as a class 10k cleanroom. Within this chamber and atop an advanced vibration-isolation bench are the 6.5 meter diameter LOTIS Collimator and Scene Generator, LOTIS alignment and support equipment. IOC included completion of the entire facility as well as operation of the LOTIS collimator in air. Wavefront properties of the collimator will be described as well as facility vibration isolation properties and turbulence levels within the collimator test chamber. User-specific test capabilities will also be addressed for two major areas of concern.

Brush and forest fires, both naturally occurring and anthropogenic in origin, in proximity to space flight hardware processing facilities raise concerns about the threat of contamination resulting from airborne particulate and molecular components of smoke. Perceptions of the severity of the threat are possibly heightened by the high sensitivity of the human sense of smell to some components present in the smoke of burning vegetation.On August 26th, 2009, a brushfire broke out north of Pasadena, California, two miles from the Jet Propulsion Laboratory. The Station Fire destroyed over 160,000 acres, coming within a few hundred yards of JPL. Smoke concentrations on Lab were very heavy over several days. All Lab operations were halted, and measures were taken to protect personnel, critical hardware, and facilities. Evaluation of real-time cleanroom monitoring data, visualinspection of facilities, filter systems, and analysis of surface cleanliness samples revealed facility environments andhardware were minimally effected.Outside air quality easily exceeded Class Ten Million. Prefilters captured most large ash and soot; multi-stage filtration greatly minimized the impact on the HEPA/ULPA filters. Air quality in HEPA filtered spacecraft assembly cleanrooms remained within Class 10,000 specification throughout. Surface cleanliness was inimally affected, as large particles were effectively removed from the airstream, and sub-micron particles have extremely long settling rates. Approximate particulate fallout within facilities was 0.00011% area coverage/day compared to 0.00038% area coverage/day during normal operations. Deposition of condensable airborne components, as measured in real time, peaked at approximately1.0 ng/cm2/day compared to 0.05 ng/cm2/day nominal.

This slide presentation discusses a mathematical model to monitor particle fallout in a cleanroom. "Cleanliness levels" do not lead to increases with regards to cleanroom type or time because the levels are not linear. Activity level, impacts the cleanroom class. The numerical method presented leads to a simple Class-hour formulation, that allows for dynamic monitoring of the particle using a standard air particle counter.

More efficient continuous-wave photonic nearinfrared mixers as terahertz sources are investigated with the motivation to develop a universal photonic local oscillator for astronomical submillimeter/terahertz receiver systems. For this, our group has developed new concepts for vertically illuminated traveling-wave (TW) photomixers. The new device called TWUni- Travelling Carrier photodiodes (TW-UTC PD) was simulated, modeled and shall be optical/terahertz tested at the Electrical Engineering Department of the University of Chile, whereas device fabrication is performed at the MC2 cleanroom facility at Chalmers University of technology. We are reporting on first progresses in this direction.

A case study of drastic photolithography defectivity reduction on i-line and Deep-UV (DUV) tools is presented. We show how this result is linked with reduction of Airborne Molecular Contamination (AMC) in clean room by combined installation of novel type of filters on tracks and on the recirculation air treatment. The root cause was identified to be the presence of acetic acid in clean room created by a reaction with the filters (mounted on track tools to exclude ammonia contamination of the process) and the photo solvent itself (here mainly 1-methoxy-2-propanol acetate: PGMEA). Crucial for the project success was the use of a real time monitoring tool to detect the sources of Volatile Organic Compounds (VOC). Finally, a model of chemical reaction of satellite defects creation is discussed based on a Time of Flight Static SIMS (TOF SSIMS) analysis together with new AMC specification for acetic acid for the photolithography area.

Assessing molecular contamination (MC) at part-per-billion (ppbV) or part-per-trillion volume (pptV) levels in cleanroom air and purge gas lines is essential to protect lithography and metrology tools optics and components. Current lithography and metrology tool manufacturer's specifications require testing of some contaminants down to single digit pptV levels. Ideally this analysis would be performed with an on-line analyzer (capable of providing almost instant results): the best analyzers currently available are only capable of providing 100 pptV detection. Liquid impinger sampling has been the dominant sample collection method for sub ppbV acidic and basic MC analysis. Impinger sampling suffers from some inherent problems that can dramatically reduce the collection efficiency such as analyte solubility and evaporative losses. An innovative solid-state trapping technology has been recently developed by SAES Pure Gas along with the CollectTorr sampling system. NIST traceable gas phase standards have been used to compare the collection efficiency of the traditional impinger technology to that of the solid state trapping method. Results varied greatly for the different acid gases with sulfur dioxide showing comparable collection efficiencies while hydrofluoric acid and hydrochloric acid showed much lower recoveries in the impingers than the solid-state traps. Ammonia collection efficiencies were slightly higher for the solid state traps and were improved in the impingers when an acidified solution was used as the collection media. The use of solid-state traps, besides being much simpler from both the handling and logistical stand point, eliminates the analyte solubility and evaporation problems frequently seen with the impinger sampling.

1. ABSTRACT Trimethylsilanol (TMS) is a low molecular weight / low boilin g point silicon-containing, airborne contaminant that has received increased interest over the past few years as an important cause for contamination of optical surfaces in lithography equipment. TMS is not captured well by carbon-based filters, and hexame thyldisiloxane (HMDSO), even though captured well, can be converted to TMS when using acidic filter media comm only used for ammonia remova l. TMS and HMDSO co-exist in a chemical equilibrium, which is affected by the acidity and moisture of their environment. This publication shows that HMDSO is converted to TMS by acidic media at concentrations typically found in cleanroom environments. This is contrary to published results that show a re-combination of TMS to HMDSO on acid media. We also demonstrate that, based on its conversion to TMS, HMDSO is not a suitable test compound for hybrid chemical filter performance, as the apparent lifetime/capacity of the filter can be substantially skewed towards larger numbers when conversion to TMS is involved. We show lifetime test results with toluene and HMDSO on acidic and non-acidic filter media. Appropriately designed, asymmetric hybrid chemical filters significantly minimize or eliminate the conversion of HMDSO to TMS, thereby reducing the risk to scanner optical el ements. Similarly, such filters can also prevent or reduce acid-sensitive reactions of other AMC wh en passing through filter systems. Keywords: TMS, HMDSO, AMC, chemical filter, filter performance, silicon, silo xanes, photolithography, optics hazing. 2. INTRODUCTION Silicon containing hydrocarbons are a clas s of airborne molecular contamination (AMC) causing persistent degradation of UV exposure tool optical surfaces

Extreme Ultraviolet (EUV) Lithography is currently viewed as the most promising approach for reaching the 22 nm node in the manufacture of silicon devices. One of the principal challenges in the ongoing EUVL research effort is the development of necessary at-wavelength metrology tools. EUV Technology worlds leading manufacturer of EUV metrology tools manufactures custom instrumentation for the utilization and analysis of short wavelength electromagnetic radiation - soft x-rays and extreme ultraviolet (EUV). Our company has pioneered the development of several stand-alone inspection, metrology, and calibration tools for EUV lithographic applications that can be operated in a clean room environment on the floor of a fab. An overview of necessary metrology tools for EUV Lithography will be presented, along with the challenges in developing these tools in order to support the successful implementation of EUV Lithography for the 22nm node. In addition, a detailed description of the EUV metrology tools we have delivered, their long term performance and stability of these tools along with our plans for developing a Reflectometer to achieve the HVM requirements will be discussed.

The fast and direct identification of possibly pathogenic microorganisms in air is gaining increasing interest due to their threat for public health, e.g. in clinical environments or in clean rooms of food or pharmaceutical industries. We present a new detection method allowing the direct recognition of relevant germs or bacteria via fluorescence-labeled antibodies within less than one hour. In detail, an air-sampling unit passes particles in the relevant size range to a substrate which contains antibodies with fluorescence labels for the detection of a specific microorganism. After the removal of the excess antibodies the optical detection unit comprising reflected-light and epifluorescence microscopy can identify the microorganisms by fast image processing on a single-particle level. First measurements with the system to identify various test particles as well as interfering influences have been performed, in particular with respect to autofluorescence of dust particles. Specific antibodies for the detection of Aspergillus fumigatus spores have been established. The biological test system consists of protein A-coated polymer particles which are detected by a fluorescence-labeled IgG. Furthermore the influence of interfering particles such as dust or debris is discussed.

The use of an electrostatic chuck to support and flatten an extreme ultraviolet (EUV) mask during scanning exposure will be a critical component to meet the stringent requirements on image placement errors in the sub-30-nm regime. Consequently, the ability to predict the response of the mask during e-chucking is necessary for the design and implementation of the e-chuck system. This research focuses on characterizing the coefficient of friction between the EUV reticle and the dielectric material of the chuck. A customized tool was constructed to test chuck and reticle samples both in air and in a vacuum chamber. Studies were conducted to identify the friction coefficient at various chucking pressures and to examine the effects of wear caused by repeated measurements on the same location of the reticle surface. All experiments were performed in a cleanroom environment. Results of the friction testing illustrate the range of values to expect for typical EUV reticles and chucks. Finite element (FE) modeling was then used to illustrate the effects of friction on the overall capability of the chuck to flatten the mask. Additional FE simulations demonstrated the magnitude of the friction force needed to ensure that the reticle would not slip during the acceleration / deceleration loading seen in the scanning exposure process.

Perfluoroalkylamine (PFAA) contamination has been observed to be a growing contamination issue in semiconductor fabs due to the increased tolerances demanded by next generation lithography processes. These contaminants are found within the cleanroom, process environments and within various tools and enclosures. As a result, effective control of PFAAs in lithographic processing and other critical environments are becoming an important filtration problem. This work was undertaken to evaluate filter performance for the removal of PFAAs and to provide an optimal filtration solution. The filter breakthrough performance of perfluorotributylamine (PFTBA), a common heat transfer fluid, is investigated over a range of environmental conditions for several commercially available adsorbent materials. The results from these accelerated tests indicate that PFAAs can be effectively removed with activated carbon-based chemical filters.

A new analytical method for semiconductor-specific applications is presented for the accurate measurement of low molecular weight, silicon-containing, organic compounds TMS, HMDSO and D3. Low molecular weight / low boiling point silicon-containing compounds are not captured for extended periods of time by traditional chemical filters but have the same potential to degrade exposure tool optical surfaces as their high molecular weight counterparts. Likewise, we show that capturing these compounds on sample traps that are commonly used for organic AMC analysis does not work for various reasons. Using the analytical method described here, TMS, HMDSO and D3 can be measured artifact-free, with at least a 50:1 peak-to-noise ratio at the method detection limit, determined through the Hubaux-Vos method and satisfying a conservative 99% statistical confidence. Method detection limits for the compounds are 1-6 ppt in air. We present calibration curve, capacity, capture efficiency, break-through and repeatability data to demonstrate robustness of method. Seventy-one real-world samples from 26 projects taken in several fab environments show that TMS is found in concentrations 100 times higher than those of HMDSO and D3. All compounds are found in all environments in concentrations ranging from zero to 12 ppm, but most concentrations were below 50 ppb. All compounds are noticeably higher in litho-bays than in sub-fabs and we found all three compounds inside of two exposure tools, suggesting cleanroom and/or tool-internal contamination sources.

Two methods for monitoring acid/base airborne molecular contamination (AMC) in 193nm lithography exposure tools, tracks, and process bays have historically been used for cleanroom and process contamination control. Ion Mobility Spectrometry (IMS) is a predominant technique used by semiconductor manufacturers for real-time AMC detection allowing for identification of subtle trends in AMC levels over time or alarming during high concentration events. Manual impinger sampling with ion chromatography (IC) analysis is a second technique used which pre-concentrates the air sample to allow for low detection limits and allows for some increased speciation of ions. The use of one or both of these techniques has a significant impact on the effectiveness of AMC detection and control, therefore, the equipment and strategy used within an AMC monitoring program can provide large competitive advantages that are not easily or quickly duplicated by other companies.

BATC has developed a new stray light test facility (SLTF) and performed initial tests demonstrating its capabilities. The facility interior is nearly all black and is a Class 5 cleanroom. Coupled with a double cylindrical chamber that reflects the specular light away from the instrument under test, the stray light control in the facility is excellent. The facility was designed to be able to test a wide variety of instruments at a range of source angles from in-field to large off-axis angles. Test results have demonstrated PST performance below 1E-9.

In January 2007, Diamond Light Source (DLS) Ltd, the new 3rd generation national synchrotron source for the UK, welcomed its first scientific users. The successful exploitation of the intense synchrotron light produced by DLS will depend to a significant extent on the quality and performance of the optics employed in the experimental stations (beamlines). An in-house facility is required for acceptance and optimization of synchrotron optics, and for fundamental research to develop new technologies. A cleanroom laboratory has been constructed at DLS to house a suite of metrology instruments capable of characterizing state-of-the-art, synchrotron optics. A micro-interferometer and an atomic force microscope, with capability to integrate the two devices, are used to assess the atomic scale roughness of x-ray optics. A Fizeau interferometer and a slope measuring profiling system are used to measure the larger scale topography of sample surfaces. These non-contact, complementary techniques allow a broad spectrum of lateral features, from 1nm to 1m, to be probed to high accuracies. We present metrology data obtained using the instruments listed above.

Stringent flatness requirements have been imposed for the front and back surfaces of extreme ultraviolet lithography masks to ensure successful pattern transfer within the image placement error budget. During exposure, an electrostatic chuck will be used to support and flatten the mask. It is therefore critical that the electrostatic chucking process and its effect on mask flatness be well-understood. The current research is focused on the characterization of various aspects of electrostatic chucking through advanced finite element (FE) models and experiments. FE models that use flatness measurements of the mask and the chuck to predict the final flatness of the pattern surface have been developed. Pressure was applied between the reticle and chuck to simulate electrostatic clamping. The modeling results are compared to experimental data obtained using a bipolar Coulombic pin chuck. Electrostatic chucking experiments were performed in a cleanroom, within a vacuum chamber mounted on a vibration isolation cradle, to minimize the effects of particles, humidity, and static charges. During these experiments, the chuck was supported on a 3-point mount; the reticle was placed on the chuck with the backside in contact with the chucking surface and the voltage was applied. A Zygo interferometer was used to measure the flatness of the reticle before and after chucking. The FE models and experiments provide insight into the electrostatic chucking process which will expedite the design of electrostatic chucks and the development of the SEMI standards.

A dedicated optics and metrology team has been assembled at Diamond Light Source to take responsibility for designing, procuring and testing a wide range of state-of-the-art x-ray optics, providing the Diamond beamlines with effective solutions to condition and focus synchrotron light. Advanced efforts are underway to design and construct a cleanroom laboratory to house a suite of metrology instruments. This will complement the Test beamline, used for a wide range of tasks including x-ray optics and detector developments, and proof of principle experiments. In collaboration with industrial and academic partners, these experimental facilities will be used to measure and develop the next generation of x-ray optics, and help the Diamond beamlines to achieve world leading performance. Details of the planning and early construction phase of the Metrology laboratory are presented, and preliminary examples of x-ray metrology measurements and research programmes.

The New Horizons (NH) Pluto probe was launched on an Atlas V-551 equipped with a five-meter payload fairing (PLF). In-situ Gel-Pak witness plates were used to monitor fall-out at spacecraft level and at Centaur level within the PLF. Based upon the composition of particles captured on a Gel-Pak that witnessed encapsulation and transport to the launch facility significant particle fall-out is associated with fairing materials of construction. The weekly variation of particle fall-out onto subsequent Gel-Pak surfaces over the course of launch preparation indicates that upward transport of particles occurred. Based upon the sum of all Gel-Pak particle counts combined with visual detection of dust on the top deck of New Horizons during installation of the radioisotope thermoelectric generator (RTG) our goal of level 450 beginning of life (BOL) was probably exceeded. A big contributor to this excedance was removal of the isolation diaphragm that normally separates the spacecraft form activity below due to mission unique requirements. The launch service provider confirmed detection of upward air movement in previous ground testing of an Atlas V fairing. Future contamination sensitive missions using the Atlas V may want to consider the following: 1) reduced PLF airflow (NH used 280 Lbm/min.), 2) ultraviolet inspection of the PLF, 3) use of isolation diaphragm, 4) in-situ particle counting. Sodium chloride was evident on many particles examined by SEM/EDS, indicating intrusion of the sea coast atmosphere into KSC cleanrooms.

A key lesson learned from the earliest optics installed in the National Ignition Facility (NIF) was that the traditional approach for maintaining cleanliness, such as the use of cleanrooms and associated garments and protocols, is inadequate. Assembly activities often negate the benefits provided by cleanrooms, and in fact generate contamination with high damage potential. As a result, NIF introduced ''clean assembly protocols'' and related practices to supplement the traditional clean room protocols. These new protocols included ''clean-as-you-go'' activities and regular bright light inspections. Introduction of these new protocols has greatly reduced the particle contamination found on more recently installed optics. In this paper we will describe the contamination mechanisms we have observed and the details of the clean assembly protocols we have successfully introduced to mitigate them.