Thin-film solar cells based on CIGS are being considered for large scale power plants as well as building
integrated photovoltaic (BIPV) applications. Past studies indicate that CIGS cells degrade rapidly when
exposed to moisture. As a result, an effective approach to encapsulation is required for CIGS cells to
satisfy the international standard IEC 61646. CIGS modules fabricated for use in large power plants can
be encapsulated with glass sheets on the top and bottom surfaces and can be effectively sealed around the
edges. In the case of BIPV applications, however, it is desirable to utilize CIGS cells grown on flexible
substrates, both for purposes of achieving reduced weight and for cases involving non-flat surfaces. For
these cases, approaches to encapsulation must be compatible with the flexible substrate requirement. Even
in the case of large power plants, the glass-to-glass approach to encapsulation may eventually be
considered too costly. We are investigating encapsulation of flexible CIGS cells by lamination. Sheets of
PET or PEN coated with multilayer barrier coatings are used to laminate the flexible cells. Results are
discussed for laminated cells from two CIGS manufacturers. In both cases, the cell efficiency decreases
less than 10% after 1000 hours of exposure to an environment of 85°C/85%RH. This paper discusses these
two approaches, and reviews results for uncoated cells and mini-modules fabricated by the former Shell
Solar Industries (SSI).
Thin film barrier coatings for protecting Organic Light Emitting Diode (OLED) displays against the environment are extremely difficult to fabricate. The coatings must have extremely low water/oxygen permeability, no defects, cover several microns of topography, and be applied at temperatures below 100°C in a process that does not compromise the performance of the display. Vitex Systems has succeeded in depositing such coatings using an organic/inorganic, thin film multilayer structure termed Barix encapsulation. In this paper results on encapsulation of OLED test pixels and passive matrix displays will be shown. Lifetime and permeability tests conducted at high temperature and humidity demonstrate that this thin film coating can meet the necessary performance requirements for commercial OLED displays. Processing parameters, layer architecture and manufacturing techniques are analyzed and discussed. Thin film encapsulated displays are used to demonstrate the utility of the encapsulation technique.
Organic light emitting diodes (OLEDs) have recently entered the market place as a competitive flat panel display technology. OLED displays are moving rapidly from small passive matrices (i.e. <3 inches diagonal) to full color active matrices based on rigid substrates. This paper is focused on new developments to help enable flexible OLED (FOLED) displays. Presented here will be high efficiency phosphorescent OLED displays that can be used in either passive or active matrix drive configurations. Passive matrix displays incorporating this technology fabricated on flexible substrates are also reported. These early demonstrations of flexible OLED displays illustrate the promise for a whole new generation of display products based on the design dimension of flexibility.
Today organic light emitting diodes (OLEDs) are entering the market lace as a competitive flat panel display technology. Rapidly OLED displays are moving from small passive matrices to full color active matrices built on conventional indium tin oxide coated glass. The work in this paper is focused on developing high resolution full color displays on flexible substrates. Presented here will be new developments in high efficiency OLED displays with the application of this technology to flexible substrates thus allowing a whole new generation of display concepts to be realized.
We describe a flexible, transparent plastic substrate for OLED display applications. A flexible, composite thin film barrier is deposited under vacuum onto commercially available polymers, restricting moisture and oxygen permeation rates to undetectable levels using conventional permeation test equipment. The barrier is deposited under vacuum in a process compatible with conventional roll- coating technology. The film is capped with a thin film of transparent conductive oxide yielding an engineered substrate (Barix<SUP>TM</SUP>) for next generation, rugged, lightweight or flexible OLED displays. Preliminary tests indicate that the substrate is sufficiently impermeable to moisture and oxygen for application to moisture-sensitive display applications, such as organic light emitting displays, and is stable in pure oxygen to 200 degrees Celsius.
Weatherable, low cost, front surface, solar reflectors on flexible substrates would be highly desirable for lamination to solar concentrator panels. The method to be described in this paper may permit such reflector material to be fabricated for less the 50$CNT per square foot. Vacuum deposited Polymer/Silver/Polymer reflectors and Fabry-Perot interference filters were fabricated in a vacuum web coating operation on polyester substrates. Reflectivities were measured in the wavelength range from .4 micrometers to .8 micrometers . It is hoped that a low cost substrate can be used with the substrate laminated to the concentrator and the weatherable acrylic polymer coating facing the sun. This technique should be capable of deposition line speeds approaching 1500 linear feet/minute<SUP>2</SUP>. Central to this technique is a new vacuum deposition process for the high rate deposition of polymer films. This polymer process involves the flash evaporation of an acrylic monomer onto a moving substrate. The monomer is subsequently cured by an electron beam or ultraviolet light. This high speed polymer film deposition process has been named the PML process- for Polymer Multi- Layer.
Large-optics coating facilities and processes at Pacific Northwest Laboratory (PNL) that were used to develop large-area high-performance laser mirrors for SDIO are now being used to fabricate a variety of optical components for commercial clients, and for novel applications for other DoD clients. Emphasis of this work is on technology transfer of low-cost coating processes and equipment to private clients. Much of the technology transfer is being accomplished through the CRADA (Cooperative Research and Development Agreement) process funded by the Department of Energy (DOE).