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Polycarbonate is the chosen material for display covers. The requirements for coatings comprise high abrasion resistance, antireflection properties and challenging environmental durability. A suitable coating has been developed and deposited onto polycarbonate by Plasma-IAD.

A hybrid antireflective coating combining homogeneous layers and linear gradient refractive index layers has been deposited using different techniques. The samples were analysed by optical characterisation based on spectrophotometric and spectroscopic ellipsometric measurements under different angles of incidence in order to precisely characterise the coatings. The Lorentz-Lorenz model has been used for calculation of refractive index of material mixtures in gradient index layers as well as some homogenous parts of the coating. The obtained refractive index profiles have been compared with the targeted ones to detect errors in processes of deposition.

Adhesion enhancement of optical thin films on TAC can be achieved by using argon-helium plasma surface pretreatment. Good adhesion anti-reflection coating on TAC with an interface layer refinement was demonstrated.

The present paper is focused on coating technologies compatible with industrial requirements, particularly on atmospheric pressure plasma technologies which are compatible with scaling to wide substrate widths (greater-than, equal or similar 0.5 m). The AP-PECVD reactors are designed for continuous air-to-air processing, and can be used for deposition of non-oxide films. Two thermal methods for atmospheric pressure processing are considered: microwave CVD and DC ArcJet-CVD. Typical thin film growth rates for PECVD are in the range of 5-100 nmBLs(sup -1) (static) and up to 2 nmBLmBLs(sup -1) (dynamic). The rates for plasma chemical etching are typically 10 times higher. A complimentary lower energy plasma source based on dielectric barrier glow discharge plasma CVD has also been explored. Developments are underway to explore uses for the coating technology, for example scratch resistant coatings on metals, barrier layers, self-clean functional surfaces and antireflective coatings. Coating materials range from silica, titania, aluminium oxide, metal composite layers, carbon and silicon nitride. Layer properties are close to data known from low pressure PECVD. Plasma chemical etching has been developed for crystalline silicon photo-voltaics. The surface textures strongly change with the precursors and the plasma parameters used.

ZrO2 and SiO2 broadband antireflection (AR) coatings are prepared by glancing angle deposition. These AR coatings exhibiting excellent optical properties and high damage threshold is applicable to used in high-energy laser system.

Characteristics of conventional and inverted InGaAs/InP thermophotovoltaic (TPV) cells with a back surface reflector (BSR) fabricated on electrically active n‐type InP substrates are presented. Thermophotovoltaic cells based on lattice matched InP‐In0.53Ga0.47As heterostructures were fabricated with the use of LPE and Zn,P diffusion technologies.In the p‐n TPV cells (conventional type, spectral range 600÷1800 nm) with a frontal p‐InGaAs layer, BSR was made on a n‐InP substrate. In the n‐p structure (inverted type, spectral range1000–1800 nm) with a frontal bulk n‐InP‐window‐substrate, BSR was formed on a p‐InGaAs layer. Antireflection coating (ARC) on the frontal cell surface consists of ZnS/MgF2 layers.Results of investigation of sub‐bangap photons reflection from InP substrates with a backside MgF2/Au mirror in the range of 1800÷2000nm are described. The reflection of BSR for InP samples with the doping level in the range of 1×1017÷6×1018cm−3 evidenced a weak dependence on their thickness and doping lev...

Micro-pyramid shaped subwavelength structures (SWSs) were integrated on both sides of a terahertz (THz) filter by means of stamping methods. Two silicon-based stamping molds fabricated via crystallographic wet etching were utilized to replicate SWSs onto cyclo-olefin copolymer (COC) films coated onto both sides of a THz filter at the same time. The SWSs act as an broadband antireflection coating to reduce the surface reflection loss in a frequency range of 0.2 THz to 1.4 THz. Compared to a THz filter without SWSs, the filter integrated with double-sided SWSs exhibits a low standing wave ratio inside the substrate and THz signal transmission enhancement of up to 10.8%. (C) 2015 Author(s).

Reflectance spectrum calculations of double- and triple-layer antireflection coatings based on porous silicon layer are performed using the optical matrix approach method. Obtained results are compared with the reflectance spectrum of the SiO 2 /TiO 2 double-layer antireflection coating. A low reflectance value of both double- and triple-layer antireflection coatings made of porous silicon is observed in comparison to that SiO 2 /TiO 2 antireflection coating. These results are of importance for solar cells application.

A two-layer bottom anti-reflective coating (BARC) concept in which a layer that develops slowly is coated on top of a bottom layer that develops more rapidly was demonstrated. Development rate control was achieved by selection of crosslinker amount and BARC curing conditions. A single-layer BARC was compared with the two-layer BARC concept. The single-layer BARC does not clear out of 200-nm deep vias. When the slower developing single-layer BARC was coated on top of the faster developing layer, the vias were cleared. Lithographic evaluation of the two-layer BARC concept shows the same resolution advantages as the single-layer system. Planarization properties of a two-layer BARC system are better than for a single-layer system, when comparing the same total nominal thicknesses.

In this contribution, we report on the current conversion efficiency status for Cu(In,Ga)Se2 (CIGS) solar cells made on soda lime glass (SLG) and flexible metallic (FM) substrates at DayStar Technologies, Inc. (DSTI). Using our research and development (RD (2) a 15.7% small area (~1.1 cm2) CIGS cell on FM substrate using Gen I process; (3) a 15.2% small area (~1.1 cm2) CIGS cell on FM substrate using a rapid activation process; and (4) a 13.5% large area (~14 cm2) CIGS cell on FM substrate using our rapid activation process. Using our Gen II production process, we have made a 13.0% small-area (1.1 cm2) CIGS cell on FM substrate. All the cells have anti-reflection coating. In this contribution, we present material and device characterization for these cells.

The investigation deals with problems of computer-aided design of wide-band antireflection coatings for semiconductor photosensitive devices (discrete photo receivers, CCD-cameras, modern security systems and others) for the near infrared spectral region (0.90 μm - 1.75 μm). Wide-band antireflection coating structures of two, four and six layers from different two-material combinations are designed and compared.

Summary form only given. Global positioning satellites (GPS) have been experiencing an anomalous, accelerated degradation of solar array power. This phenomenon, analyzed since the early 80's, remains unexplained. Recently, low-energy ( 10 keV). After each implant step, the optical properties of the samples are measured. Results of this investigation will be presented

A step-index optical waveguide with an antireflection coating is analyzed using the finite-difference time-domain (FD-TD) method combined with the perfectly matched layer absorbing boundary condition (PML-ABC). It is demonstrated that the numerical simulations having a dynamic range over that for the Mur absorbing boundary condition can be obtained for a single-layer coating. The analysis of a double-layer coating reveals the transient behavior of reflected fields.

This paper describes a top-emitting OLED structure that implements both low ambient light reflection within the OLED structure and reasonable emission efficiency. Ambient light reflection from a top-emitting device can be effectively suppressed by using a moderate bottom reflector and top antireflection coating, meanwhile retaining acceptable EL efficiency and other viewing characteristics for display applications.

The wet chemical sol-gel processing paves the way to the versatility and ease of liquid film deposition techniques for a variety of inorganic and hybrid coating materials. Liquid film deposition [1] in general involves the application of a liquid precursor film on a substrate which then is converted to the desired coating material in a subsequent post-treatment step.

We describe the super antireflection (AR) coatings of less than -60 dB (R < 0.0001%) of two layer V-coating and of less than -50 dB (R < 0.001 %) of four layer at 1.5 μm.

An optical self-aligned flip-chip packaging technique for tilted semiconductor optical amplifier arrays is reported. It uses a Si motherboard with V-grooves for self-alignment between the tilted SOA array and angle polished fibre arrays. Fibre-to-fibre gain of 14+or-1 dB and ripple +or-0.1 dB without antireflection coating on the fibres have been achieved.

The experimental result of a more practical solar cell antireflection coating (ARC)- SiON film is presented. The advantage of employing SiON film is that PECVD grown SiON films needs less maintenance than grown SiN films. The thick deposited SiON attached on the PECVD chamber walls can be easily cleaned off by applying clean gas into the chamber; this can efficiently shorten equipment maintenance time, and increase production. In the SiON process, the desired film growth rate, reflectance, and refractive index are attainable by changing O/sub 2/ flow.

The analysis of the I-V characteristics of a CdS/CdTe heterojunction shows the strong influence of the time of deposition of CdTe on the photo-electrical parameters. The best parameters with no antireflection coating, J/sub sc/=24.8 mA/cm/sup 2/, V/sub oc/=0.82 V, FF=0.48, /spl eta/=9.76% are obtained in the case when time of deposition of CdTe is 3.5 min. The photoresponse decreases with increasing CdTe thickness. The photosensitivity covers the wavelength range from 0.50 /spl mu/m to 0.86 /spl mu/m for all cells. The most efficient carrier generation and collection is for the structure with the time of the CdTe layer deposition of 3.5 min.

Dr. phil. habil. Walter Heinrich Geffcken was the first senior researcher to get involved in full time optical coating research at the Jenaer Glaswerk Schott & Gen. Due to circumstances beyond his control he was forced to work in secrecy and without scientific peer exchange. Several of his results were rediscovered many years later. When asked in 1992 to contribute to this book an article on his early work in optical coatings, he gladly accepted. He wrote several letters presenting his views and suggesting topics. He asked for copies of his meticulous internal reports which had survived the dramatic transfer from Jena to the new location in Mainz. But fate did not allow him to finish this task. Walter H. Geffcken died, 91 years old, on April 4, 1995. Now it is up to us to finish the task.

The first part of this thesis covers techniques for the local analysis of current production (LBIC) and current losses (thermography) in solar cells. In the second part, surface treatment of silicon by plasma etching and silicon nitride deposition (LPCVD, PECVD and sputtering techniques) is discussed.

This paper discusses questions of the development of a protective antireflection coating with a diamondlike layer for germanium windows of thermal-vision devices. The hybrid coating thus developed has enhanced transmission in the 8–12-μm region by comparison with an ordinary diamondlike coating.

Several preliminary photovoltaic cells have been fabricated using cleaved substrates of p-type single crystal CuInSe/sub 2/ with the structure Au/CuInSe/sub 2CdS/CdO/Au, where the CdS was deposited by dipping and the CdO by DC reactive sputtering from a cadmium target. The CuInSe/sub 2/ substrates were extracted from void-free and crack-free ingots, grown by the vertical Bridgman method from stoichiometric starting proportions; the cleaved planes involved were (112) and (101). Under 100 mW/cm/sup 2/ of simulated solar illumination, the short circuit current density, j/sub sc/, of these devices was found to depend on the thickness of the CdO layer and, in at least one cell, j/sub sc/ was found to exceed 40 mA/cm/sup 2/ and V/sub oc/ to exceed 0.4 volt for an effective CdO area of about 7 mm/sup 2/, without the use of an antireflection coating. These preliminary results are subject to independent confirmation. >

We report on the development of p-on-n GaInP/sub 2//GaAs two-terminal, monolithic cascade cells. The devices are of interest for space applications because they have higher efficiencies and power-to-weight ratios than existing single junction devices currently in use, they can be readily used in current satellite array designs, and they are compatible with current manufacturing capabilities at facilities such as the Applied Solar Energy Corporation. The p-on-n cascade cells have been grown at RTI by atmospheric pressure organometallic vapor phase epitaxy at 650/spl deg/C on n-type GaAs. The best device to date, with active area of 0.141 cm/sup 2/, has an active area efficiency of 20.1 percent under AM0 illumination, before an antireflection coating (ARC). Taking into account the ARC and a grid with a 5 percent obscuration, the device projects to a total area efficiency of 25.2 percent, nearly equal to that achieved for n-on-p cells. Devices of area 4 cm/sup 2/ have also been grown. The large-area devices have attained efficiencies of 21.8 percent under AM0 illumination, with ARC.

A description is presented of state-of-the-art 1024*1024 pixel CCD (charge coupled device) imagers. Additionally, in order to provide the highest possible quantum efficiency, special back-side thinning, post-processing, antireflection coating, and mounting/packaging capabilities have been developed. A high degree of capability has been achieved in building high performance camera systems to utilize the potential of the CCD. The basic design and philosophy behind this CCD are outlined, along with test and characterization results. >

Summary form only given. The Nd/sup 3+/:Ca/sub 4/GdO(BO/sub 3/)/sub 3/ crystal (Nd:GdCOB) has already been demonstrated to be efficient for self-frequency doubling in the green when a diode-pumped Nd:GdCOB crystal is placed in a concave-concave cavity. We have also reported on the performances of diode-pumped Nd:GdCOB crystals put in a short plano-plano cavity consisting of a Nd:GdCOB crystal with antireflection coating and two plane mirrors put very close to the crystal.

Utilizing the hydrogen-rich porous surface and aluminum ability to generate vacancies a new passivation scheme is proposed for mc-Si solar cells with porous silicon as an antireflection coating and aluminum as a back contact. This combination achieves a synergetic effect with aluminumn providing injection od vacancies through which hydrogen atoms from the porous silicon surface can diffuse into the mc-Si and effectively passivate the bulk.

A transparent low refractive index SiO2 film laminated on a glass substrate at room temperature by photochemical reactions with the Xe2* excimer lamp (172nm). This SiO2 film grown on the fused silica glass was proved to avoid reflection of light.A refractive index of the SiO2 film was 1.36. After annealing the film for one hour at 200 degrees centigrade, the refractive index increased to 1.42. The refractive index increased as the F atom density in the SiO 2 film decreased.

Computer modeling of one-layer antireflection coating based on SiO2 and TiO2 mixed oxides was carried out for solar elements. It was concluded that a photoelectric current can be increased by varying the thickness of the covering within the limits of 55–90 nm, while the concentration of SiO2 in TiO2 shall not exceed 30%. A method of magnetron spattering was offered as a method for application of the coating based on a SiO2-TiO2 mixture.

Any designed two-layer antireflection coating with calculated phase thicknesses z and y of the first and second matching layers, respectively, always allows the following “looking-glass” transformation: z ?2? ? z, y ?2? ? y .

A perfect antireflection coating would remove the reflection from the interface between two media for all wavelengths and angles of incidence. In this paper the degree to which this can be achieved is investigated numerically, theoretically and experimentally.

A previous investigation [B. G. Martin, J. Appl. Phys. 66, 1931 (1989)] showed that acoustical symmetric multilayer (ASM) structures could be used as antireflection (AR) coatings. In the present investigation, we consider the AR properties of stacked ASMs, which offer a practical means for achieving graded impedance structures for virtually any gradient profile.

Deep ultraviolet (DUV) bottom anti-reflective coating (BARC)- to-resist compatibility is a key component in process optimization. In addition to the reduction of optical interference effects, BARC's also improve CD uniformity by preventing substrate contamination. However, if the BARC is not compatible with the resist, it can create adverse affects. If the acidity level of the BARC is not tuned to the resist for example, the profiles will foot or undercut, or if the BARC-to-resist developer interactions are not considered, high levels of post-develop defects will most likely occur. Etch selectivity, topography conformality and bowl/drain compatibility are other factors to consider when selecting a BARC. This paper follows the progressions of the leading DUV BARC's for Acetal-based resist systems and addresses the problems that could be encountered with implementing a BARC process. From DUV32 to the topography-conforming DUV42 and finally to the profile-enhancing DUV44, the 248 nm BARC's are continually evolving to resolve the BARC-to-resist compatibility issues.

The Electrostatic Self-Assembly (ESA) technique possesses great advantages over traditional thin film fabrication methods, making it an excellent choice for a number of applications in the fields of linear and nonlinear optics, electronics, sensing and surface coatings. The feasibility of fabricating linear optical interference filters by ESA methods is demonstrated in this thesis work. Basic single-anion/single-cation ESA films are synthesized and their optical parameters -- refractive index and average thickness for individual bilayer -- are investigated to provide a basis for the in-depth design of optical filters. High performance dielectric stack filters and narrowband and wideband antireflection coatings are designed using TFCalc simulation software and are fabricated by ESA. Both bulk film sensitivity and layer sensitivity to manufacturing errors are provided. The significant agreement between simulation and experiment demonstrates the strong capability of ESA to precisely control the refractive index and produce excellent thin film filters. The performance of optical thin film filters is largely enhanced compared to the results of previous methods. The experiment results indicate that the ESA process may be used to fabricate optical filters and other optical structures that require precise index profile control. Master of Science

The new idea to fire contacts through porous silicon antireflection coating is tested for the first time from the vewpoint of PS eligibility towards a rapid high-temperature process.

We present new results from the characterisation of a fully depleted 2048-row by 2048-column (2K×2K) CCD on high resistivity silicon. The CCD was fabricated at the Lawrence Berkeley National Laboratory (LBNL). This device represents a one hundred-fold increase in CCD size compared to devices previously made at LBNL. The large CCD size allows us to do accurate charge transfer efficiency measurements. A two-layer antireflection coating is modelled and compared with laboratory measurements of both quantum efficiency and reflectivity.

Astrophotography covers a wide variety of disciplines. Sometimes, it is necessary to perform a few calculations in order to determine the effective focal length and f/ratio of your telescope. Such calculations can permit you to more accurately determine what exposure time you should use, which in turn will save film. A little math is particularly important when auxiliary optics are used to change the effective focal length of your telescope. Shooting an astrophoto without first knowing the correct exposure (or at least something close to the correct exposure) is literally like taking a “shot in the dark”.

We describe here the continuing research in large-area, back-illuminated CCD imagers at MIT Lincoln Laboratory in collaboration with the University of Hawaii Consortium. Among the developments are a two-layer antireflection coating of TiO2/Al2O3 combined with thick (>40 μm) substrates aimed at broader bandwidth and reduction of Fabry-Perot interference effects in the near infrared. Recent work on the orthogonal-transfer CCD (OTCCD) is described in which the previously noted problem of pockets has been solved with a four-layer polysilicon process. Two new larger OTCCDs (1024×1320 and 2k×4k) have been designed and are in fabrication. The larger OTCCD will use a recently designed four-side-buttable package.

REOSC has developed a new hard multispectral coating on ZnS compatible with military environment conditions. In extreme conditions the coating exhibit a pretty good behavior. Developed on ZnS, other substrates can be used. The coating itself can be tuned from UV up to 10micrometers . High transmission in visible spectrum >= 90 percent is achievable for an antireflection coating tuned around 8-10 micrometers on ZnS. The coating is laser compatible.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Results of new CMOS-integrated PIN photodiodes in optoelectronic integrated circuits (OEICs) for applications in optical storage systems, in optical data transmission and in optical interconnects are presented. The rise and fall times of the integrated PIN photodiodes are below 0.3 us. The CMOS-integrated PIN photodiodes are sufficient for a NRZ data rate of 1.5 Gb/s and the results show that PIN CMOS receiver OEICs in submicron technologies enable data rates up to 1 Gb/s. These photodiodes combine this high speed with a high quantum efficiency of approximately 50%. The further improvement of their quantum efficiency above 90% by the integration of an antireflection coating is discussed. Low-offset PIN-CMOS-OEICs for application in digital-versatile-disk (DVD) systems with bandwidths in excess of 32 MHz are presented. A high speed PIN-CMOS-OEIC in 1.0 /spl mu/m technology for optical data transmission exhibits a data rate of 622 Mb/s.

The problem of guided waves in solid/fluid/solid trilayers has been investigated in great detail both theoretically and experimentally. Lloyd and Redwood were the first to investigate guided wave propagation in a layered plate composed of two solids with perfect contact, slip, or a fluid layer at their interface [1]. Rokhlin et al. studied the elastic interface wave guided by a thin film between two solids and utilized it in predicting the strength of adhesive bonds [2,3]. Couchman et al. [4] and Guyott and Cawley [5] reported on the phenomenon of resonance splitting in the vicinity of classical Lamb modes in symmetrical trilayers. Laperre and Thys investigated elastic wave dispersion in both symmetric and asymmetric trilayers composed of two solid plates separated by a fluid layer [6]. A number of papers have appeared on the use of trilayers as antireflection coating [7–9].

In this study, the enhanced performance of a triple-junction GaAs-based solar cell using a SiO 2 -nanopillar/SiO 2 /TiO 2 graded-index antireflection coating (GI-ARC) was demonstrated. The optical reflectance, photovoltaic current-voltage (I-V), and external quantum efficiency (EQE) of a cell with a SiO 2 /TiO 2 double-layer (DL) ARC and a cell with a GI-ARC were measured and compared. The cell with a GI-ARC exhibited the lowest optical reflectance. Thus, the average EQE enhancements (ΔEQE) of the cell with a GI-ARC compared to the cell with a DL-ARC were 5.88% for the top cell and –1.56% for the middle cell. In addition, a small difference in the photocurrent generated between the top cell and the middle cell was achieved. Finally, an additional 0.52% increase (from 24.99% to 25.51%) in conversion efficiency was obtained.

We have studied the optical transmission spectrum of a surface film of erbium oxide and evaluated the effect of clarification for the surface of a silicon-based photovoltaic converter with an antireflection coating of this material. It is established that erbium oxide films are highly transparent in a broad wavelength range from 250 to 1050 nm and ensure a decrease in the coefficient of reflection of a silicon surface down to 1–4.5%. The antireflection coating of erbium oxide increases the short-circuit photocurrent of the silicon-based photovoltaic converter by more than 38%.