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A nano-precision-capable, multi-agent, flexible positioning platform can be used to increase (metrology) throughput in semiconductor industry by parallelisation of measurements. It is based on magnetic levitation (MagLev) and 6-DoF control, combining large x- and y-motions with sub-nanometer scanning resolution in a single stage. The system architecture of this flexible positioning platform has the ability to operate many devices in parallel. Each device can function as a lab-on-instrument to perform various tasks at the nanoscale, e.g. metrology, inspection, deposition, transport, cleaning, etc. A demonstrator set-up was successfully designed, built and tested.

This project is aiming to realize miniature self-contained carriers that can independently perform positioning and scanning tasks on nano-scale. Such carriers can support agents for performing tasks such as inspection, deposition, repair, and cleaning. All at the nano-scale. The carriers can make large movements in X-and Y-direction and have a smaller range in Z, and rotations. This is sufficient to cover relevant surfaces in, for instance, semicon industry, such as wafers and reticles.

TNO is developing a High Power Adaptive Mirror (HPAM) to be used in the CO2 laser beam path of an Extreme Ultra-Violet (EUV) light source for next-generation lithography. In this paper we report on a developed methodology, and the necessary simulation tools, to assess the performance and associated sensitivities of this deformable mirror. Our analyses show that, given the current limited insight concerning the process window of EUV generation, the HPAM module should have an actuator pitch of ≥ 4 mm. Furthermore we have modelled the sensitivity of performance with respect to dimpling and actuator noise. For example, for a deformable mirror with an actuator pitch of 4 mm, and if the associated performance impact is to be limited to smaller than 5%, the actuator noise should be smaller than 45 nm (rms). Our tools assist in the detailed design process by assessing the performance impact of various design choices, including for example those that affect the shape and spectral content of the influence function.

We have developed a high speed, miniature scanning probe microscope (MSPM) integrated with a Positioning Unit (PU) for accurately positioning the MSPM on a large substrate. This combination enables simultaneous, parallel operation of many units on a large sample for high throughput measurements. The size of the MSPM is 19 × 45 × 70 mm3. It contains a one-dimensional flexure stage with counter-balanced actuation for vertical scanning with a bandwidth of 50 kHz and a z-travel range of more than 2 μm. This stage is mechanically decoupled from the rest of the MSPM by suspending it on specific dynamically determined points. The motion of the probe, which is mounted on top of the flexure stage is measured by a very compact optical beam deflection (OBD). Thermal noise spectrum measurements of short cantilevers show a bandwidth of 2 MHz and a noise of less than 15 fm/Hz1/2. A fast approach and engagement of the probe to the substrate surface have been achieved by integrating a small stepper actuator and direct monitoring of the cantilever response to the approaching surface. The PU has the same width as the MSPM, 45 mm and can position the MSPM to a pre-chosen position within an area of 275×30 mm2 to within 100 nm accuracy within a few seconds. During scanning, the MSPM is detached from the PU which is essential to eliminate mechanical vibration and drift from the relatively low-resonance frequency and low-stiffness structure of the PU. Although the specific implementation of the MSPM we describe here has been developed as an atomic force microscope, the general architecture is applicable to any form of SPM. This high speed MSPM is now being used in a parallel SPM architecture for inspection and metrology of large samples such as semiconductor wafers and masks.

This paper aims at unraveling the mystery of damage in high speed AFMs for 1X node and below. With the device dimensions moving towards the 1X node and below, the semiconductor industry is rapidly approaching the point where existing metrology, inspection and review tools face huge challenges in terms of resolution, the ability to resolve 3D, and throughput. In this paper, we critically asses the important issue of damage in high speed AFM for metrology and inspection of semiconductor wafers. The issues of damage in four major scanning modes (contact mode, tapping mode, non-contact mode, and peak force tapping mode) are described to show which modes are suitable for which applications and which conditions are damaging. The effects of all important scanning parameters on resulting damage are taken into account for materials such as silicon, photoresists and low K materials. Finally, we recommend appropriate scanning parameters and conditions for several use cases (FinFET, patterned photoresist, HAR structures) that avoid exceeding a critical contact stress such that sample damage is minimized. In conclusion, we show using our theoretical analysis that selecting parameters that exceed the target contact stress, indeed leads to significant damage. This method provides AFM users for metrology with a better understanding of contact stresses and enables selection of AFM cantilevers and experimental parameters that prevent sample damage.

With the device dimensions moving towards the 1X node, the semiconductor industry is rapidly approaching the point where 10 nm defects become critical. Therefore, new methods for improving the yield are emerging, including inspection and review methods with sufficient resolution and throughput. Existing industrial tools cannot anymore fulfill these requirements for upcoming smaller and 3D features, since they are performing at the edge of their performance. Scanning probe microscopy (SPM) has the ability to accurately measure dimensions in the micrometer to nanometer scale. Examples of applications are surface roughness, channel height and width measurement, defect inspection in wafers, masks and flat panel displays. In most of these applications, the target area is very large, and, therefore, the throughput of the measurement plays an important role in the final production cost. Single SPM has never been able to compete with other inspection systems in terms of measurement speed, thus has not fulfilled the industry needs in throughput and cost. Further increase of the speed of the single SPM helps, but it still is far from the required throughput and, therefore, insufficient for high-volume manufacturing. Over the past three years, we have developed a revolutionary concept for a multiple miniaturized SPM heads system, which can inspect and measure many sites in parallel. The very high speed of each miniaturized SPM unit allow the user to scan many areas, each with the size of tens of micrometers, in a few seconds. This paper presents an overview of the technical developments and experimental results of the parallel SPM system for wafer and mask inspection.

Optical beam deflection (OBD) measurement method is very popular in various types of scanning probe microscopy (SPM) and micro/nanomechanical sensors to measure a mechanical motion. This paper reports the detail design and implementation of a very low drift (2 nm over 1000 s), high bandwidth (40 MHz) and low noise (15 fm/VHz) OBD measurement setup that can be used in metrological SPM. The noise, bandwidth and stability of the setup and the thermo-mechanical behavior of SPM cantilevers were systematically characterized. The influences of optical beam spot size, power of the laser beam and the type of position sensitive detector on the total measurement noise for different preamplifications were analyzed in detail. Consequently, recommendations for further improvements of the OBD systems in SPMs and MEMS sensors are given. The results can be used in future high speed, high accurate and low drift SPMs and MEMS sensors applications.

The main driver for Semiconductor and Bio-MEMS industries is decreasing the feature size, moving from the current state-of-the-art at 22 nm towards 10 nm node. Consequently smaller defects and particles become problematic due to size and number, thus inspecting and characterizing them are very challenging. Existing industrial metrology and inspection methods cannot fulfil the requirements for these smaller features. Scanning probe Microscopy (SPM) has the distinct advantage of being able to discern the atomic structure of the substrate. It can image the 3D topography, but also a variety of material, mechanical and chemical properties. Therefore SPM has been suggested as one of the technologies that can fulfil the future requirements in terms of resolution and accuracy, while being capable of resolving 3D futures. However, the throughput of the current state-of-the-art SPMs are extremely low, as compared to the high-volume manufacturing requirements. This paper presents the development of an architecture[1] for a fully automated high throughput SPM, which can meet the requirements of future process metrology and inspection for 450 mm wafers. The targeted specifications of the concept are 1) inspecting more than 20 sites per wafer, 2) each site with dimension of about 10 × 10 μm2 (scalable to 100 × 100 μm2) and 3) with a throughput of more than 7 wafers per hour, or 70 wafers per hour with a coarse/fine scanning approach. The progress of the high throughput SPM development is discussed and the baseline design of the critical sub-modules and the research issues are presented. © 2013 SPIE.

TNO Science and Industry and MECAL have developed a six degree of freedom vibration isolation system that suppresses both floor vibrations and direct forces on a table top. The achieved reduction of transmissibility and compliance is 40 dB between 1 and 50 Hz in vertical direction, and 30 dB between 1 and 20 Hz in horizontal direction. Key elements of the system are a newly designed absolute vibration sensor, and two solutions to the horizontal tilting problem.

Electrosurgery enables cutting and coagulation (desiccation) of tissue for Minimally Invasive Surgery. Measurements performed by TNO with an infrared camera showed that the forceps of an endoscopic instrument can be over 300°C in temperature. During electro-surgery the surgeon relies on the power control and endoscopic images to perform the procedure successfully. Manipulation of tissue with the present forceps does not give accurate tissue information due to the presence of friction in the transmission mechanism and in turn force, control of the operating surgeon is poor. The latest developed instruments incorporates sensors and actuators that enable better control of force application on the tissue and give a better feeling of the tissue to the surgeon. TNO works for EFI BV on the development of a surgical instrument that senses and controls the gripping force even during electrosurgery. Electric sensors and actuators experience Electro Magnetic Interference during the use of electro-surgery, making it impossible to control the force. The high temperature that arises at the forceps influences and possibly destroys the sensors when positioned nearby the heat source. Based on the experience with optical fiber sensors TNO has developed an instrument that is immune to EMI and withstands temperatures up to 200°C. This optical sensor is based on a Fiber Bragg Grating (FBG). The FBG read out system, named the interrogator, transfers the optical fiber signal from the mechanical local strain. By this way the force exerted on the tissue and its resistance can be measured. However this sensor system is also sensitive to temperature changes. To control accurately he gripping force, the measurement must be independent of temperature. Therefore the thermal load at the forceps were measured and analyzed. The results are used for the instrument design and location of sensors.

TNO, in cooperation with Micromega-Dynamics, SRON, Dutch Space and CSL, has designed a compact breadboard cryogenic delay line for use in future space interferometry missions. The work is performed under ESA contract in preparation for the DARWIN mission. The breadboard (BB) delay line is representative of a future flight mechanism, with all materials and processes used being flight representative. In order to enable single stage OPD actuation, the delay line needs to have: • low moving mass; • low friction variations (e.g. stick/slip, bearing noise, power and signal wire torques); • low hysteresis; • linear behaviour. An extensive trade off study has been performed to select the best concept for the DARWIN ODL [2]. TNO applies a minimum-number-of-stages philosophy to all delay lines it develops. A smaller number of actuation stages simplifies the OPD control algorithm The selected concept has a single stage voice coil actuator for Optical Path Difference (OPD) control, driving a two mirror cat’s eye. Five magnetic bearings constrain 5 degrees of freedom (the OPD controller constrains the other degree of freedom) and provide frictionless and wear free operation with zero-hysteresis.

A Darwin precursor breadboard, comprising both fine lateral and longitudinal metrology sensors was designed, built and partially tested. The lateral metrology sensor was designed and built by TNO TPD and more than meets the imposed requirements. The longitudinal metrology sensor consists of a dual wavelength interferometer with an integrated delay line for optical path stabilisation. Here TNO TPD supplied the delay line and implemented the optical path difference stabilisation control. Experiments under ambient conditions show that noise reduction up to five orders of magnitude is achievable.

The aim of HARMONOISE Work Package 1.1 is the characterisation and modelling of road vehicle noise emission. Measurement of partial sources related to either the drive line or the tyre-road contact of moving vehicles and their contribution to the total vehicle pass-by noise is one of the research issues. TNO TPD has developed array measurement techniques that enable the assessment of 'calibrated' source strengths levels of moving complex sound sources and provide spatial information of the source strength distribution. The Dutch ministry of Environment (VROM) supported the application of these techniques by TNO TPD in a joint experiment with TRL within the European HARMONOISE project. The objective was to show the applicability of the methods and to demonstrate their specific features and possibilities. Data from one-dimensional (Syntacan) and two-dimensional (Acoustic Camera) antenna measurements on passing passenger cars and heavy vehicles were compared with single microphone measurement results. Based on these results it can be concluded that the Acoustic Camera and Syntacan can serve in the assessment of road vehicle noise. The methods may be used for various objectives such as monitoring of tyre-road noise and drive-line noise in real traffic and determining effects of the road surface on tyre-road noise.

In national and European discussions, it appears that the conventional sound measurement techniques are insufficient to answer some relevant questions with respect to source strength of road vehicles. An example of such a question is: What is the importance of tyre-road noise on the one hand and drive-line noise on the other hand in every day traffic? TNO TPD has developed measurement techniques, based on array technology, that enable the assessment of source strengths of complex sound sources, such as passing road vehicles, passing trains or industrial sources. These methods aim to distinguish the different partial sources in one dimension (Syntacan) or two dimensions (Acoustic Camera) and to measure their calibrated source-strength levels. The Dutch ministry of Environment (VROM) supported the application of these techniques by TNO TPD within the European HARMONOISE project. The objective was to show the ability of array measurements to provide both sound exposure levels (SELs) and heights. Tests were conducted at TRL (UK) to determine the accuracy of two array methods developed by TNO TPD by comparison with the subtraction method. The data measured by TNO TPD resulted in one-dimensional as well as two-dimensional 'sound photographs' of the vehicles, in different circumstances. The 'sound photographs' present calibrated source strength levels with similar accuracy as those obtained with single microphone techniques measured by TRL and on top of that, provide spatial information of the source strength distribution. Based on these results it can be concluded that the Acoustic Camera and Syntacan can serve in the assessment of road, vehicle noise. This could be done in various ways and for various objectives such as monitoring of tyre-road noise in real traffic, determining effects of the road surface on tyre-road noise and drive-line noise.

Akoestische holografie is een geluidmeettechniek waarbij een ruimtelijk geluidveld wordt vastgelegd door geluiddruk op een vlak te meten. Deze techniek maakt gebruik van de uit de optiek bekende Rayleigh integraal die beschrijft hoe het geluidveld in een denkbeeldige ruimte beschreven kan worden met een geluiddrukverdeling op de wanden van die ruimte. Geluidbronnen mogen zich daarbij overigens alleen buiten de ruimte bevinden, niet erin. Kenmerkend voor een hologram is dat niet alleen de geluiddruk, maar ook en vooral de fase van de geluidgolven bepaald wordt. Juist die fase geeft informatie over de richting waarin golven zich voortplanten en dat is weer onontbeerlijk voor transformaties naar een ruimtelijk geluidveld. Deze fase kan bij een stationair geluidveld gemeten worden ten opzichte van een punt in het hologram of een opnemer op de bron. Akoestische holografie wordt commercieel vooral gebruikt in de auto-industrie voor het vastieggen van de geluiduitstraling van met name motoren. Verder wordt holografie toe gepast in onderzoeksachtige toepassingen waarbij getracht wordt meer inzicht te krijgen in het akoestisch gedrag van allerlei, vooral plaatachtige constructies.

Voor de bestrijding van lawaai wordt veelal gebruik gemaakt van passieve dempingsmethoden. Voorbeelden zijn de geluiddempers in een auto-uitlaat en de geluid-isolerende omkasting van een dieselgenerator. Daarnaast kan ongewenst geluid worden bestreden met behulp van anti-geluid. Dit is een actieve reductiemethode, waarbij door toevoeging van extra geluid het totale geluidsniveau wordt teruggebracht.

Unwanted sound can be cancelled by adding to it sound of identical strength and opposite phase. This type of sound reduction is also called Anti-Noise or Active Noise Control and was patented by the German physicist Paul Lueg back in 1933. Although some researchers tried to make anti-noise systems work in practice, results were poor due to lack of understanding of the interaction between acoustics and electronic control systems. Appropriate electronic hardware was not available either. Most of the problems have been largely mastered during the past decades and this explains the growing interest in this type of sound control. Active noise reduction is now available as a high-tech environmental control tool in such applications as ventilation ducts, car interiors, mufflers, aeroplane cabins, refrigerators and cooker-hoods.

Eén van de grootste dagelijkse ergernissen zijn lawaai- en geluidsoverlast. Om die problemen te beperken of te bestrijden wordt wereldwijd veel onderzoek gedaan. Ook in Nederland, waar de Technisch Physische Dienst van TNO en de Technische Universiteit in Delft het voortouw hebben en opmerkelijke resultaten bereiken. Wat te denken van het bestrijden van lawaai met lawaai als geruisloze oplossing voor veel herrieproblemen. Een bijdrage over de inzet van geluid als wapen tegen ongewenst kabaal.