Energy Conversion Devices, Inc.

United Solar Systems Corporation

Sovonics Solar Systems

Kevin R Hoffman

Prem Nath

Timothy D Laarman

Joachim Doehler

Troy Glatfelter

David A Gattuso

Jon Call

Gary M Didio

Subhendu Guha

Chi C Yang

Arindam Banerjee

Mark Lycette

Kermit Jones

Kais Younan

David Wolf

John Call

Gary M DiDio

Therese McDonough

Gary DiDio

An optically enhanced back reflector for a photovoltaic device includes a back reflector layer of aluminum having a multi-layered, reflectivity enhancement member deposed thereon. The multi-layer enhancement member includes at least one pair of first and second layers, the first layer having a low index of refraction and the second layer having a high index of refraction. A layer of transmissive conductive oxide is disposed between the optically enhanced back reflector and the photovoltaic device.

Optically enhanced photovoltaic back reflector

A photovoltaic roofing shingle includes a strip of roofing material having an overlap portion, and a plurality of tab portions depending therefrom. Each of the tab portions includes a photovoltaic generating device affixed thereto. The photovoltaic devices are electrically interconnected, and each photovoltaic shingle member includes a pair of electrical terminals for delivering power from said photovoltaic devices. In use, the shingle members are affixed to a roof so that the tab portions of one row of shingles cover the overlap portion of an adjoining row. Electrical interconnection may be made through the roof to the inside of the building, or to a point atop the roof.

Photovoltaic shingle system

In continuous apparatus for the glow discharge deposition of amorphous silicon alloy solar cells of p-i-n-type configuration in a plurality of interconnected, dedicated deposition chambers, a plasma bar operatively disposed between at least the plasma regions in which the layer pairs of amorphous silicon alloy material defining the major semiconductor junction of the solar cell are deposited. The plasma bar is adapted to initiate a plasma so as to prevent chemically adsorbed contaminants from deleteriously affecting the surface of the first deposited of the layer pair, thereby improving the open circuit voltage of the solar cell. In a similar manner, the plasma bar may also be provided between the layer pairs of amorphous silicon alloy material which combine to define the minor semiconductor junction of the solar cell. Finally, a plasma bar may be disposed between the oxide-based layer of a back reflector for reducing oxygen contamination of the silicon alloy material deposited thereupon.

Interfacial plasma bars for photovoltaic deposition apparatus

A multilayered, light-scattering back reflector for a photovoltaic device, said back reflector including a first relatively hard, textured layer atop a substrate and a second highly reflective layer conformally disposed atop the first layer. The back reflector may further include a third light scattering layer formed atop said second layer, said third layer adapted to further provide a barrier layer between the body of semiconductor material from which the photovoltaic device is formed and the multilayered back reflector.

Multilayer light scattering photovoltaic back reflector and method of

An improved gas gate (34) is adapted to operatively interconnect to adjacent chambers in which process gases are introduced for depositing a first layer (16) upon a substrate (11) in a first chamber (28) and different process gases are introduced for depositing a second layer (18) in the second chamber (30) in continuous low pressure glow dicharge deposition process. A plurality of electrodes (60) and grounded shields (62) are positioned in the isolation passageway (92) of gas gate (34). The electrodes (60) have a potential sufficient to create a plasma from any gas molecule escaping from one of the deposition chambers. After the plasma is formed it is attracted to and captured or plated on the shield (62) preventing the gas plasma from landing on the substrate material (11) or passing through the gas gate. The present invention reduces the back diffusion of gases through the gas gate by actively eliminating free gas molecules by ionizing them to form a plasma and capturing the plasma ions in a permanent fashion.

Chemically active isolation passageway for deposition chambers

Apparatus for shielding substrates from plasma developed adjacent the ends of r.f. powered cathodes, the apparatus adapted for use in a glow discharge deposition system in which successive amorphous semiconductor layers are deposited onto a substrate. The deposition system includes at least one deposition chamber into which process gases are introduced and disassociated in the presence of electrodynamic fields created between a cathode and a substrate. The shielding apparatus of the present invention comprises a pair of relatively narrow, elongated plates adapted to be spacedly disposed in the deposition chamber so as to lie in a plane substantially parallel to the plane of the substrate. By disposing one of the plates adjacent each of the ends of the cathode, only homogeneous semiconductor films formed by uniform electrodynamic fields produced adjacent the central portion of the cathode are deposited onto the substrate. The shielding plates are preferably coated with a polyimide film to prevent discharge in the area between the shielding plates and the substrate.

Substrate shield for preventing the deposition of nonhomogeneous films

A method for introducing sweep gas through a baffle system adapted for use with glow discharge deposition apparatus in which successive amorphous semiconductor layers are deposited on a substrate. The deposition apparatus includes at least a pair of adjacent dedicated deposition chambers into each of which different process gases are introduced, the chambers being operatively connected by a gas gate. Inert gases are swept through the gas gate to minimize back diffusion of process gases from the chambers. The baffle system is adapted to prevent said sweep gases from entering into turbulent flow when traveling through the gas gate passageway. Further, a sufficient volume per unit time of sweep gas is introduced to insure that some sweep gas flows into the cathode region of the first chamber, thereby substantially preventing process gases and plasma from escaping from the cathode region and forming silane powder.

Method for introducing sweep gases into a glow discharge deposition

A system for introducing, confining and evacuating process gases adjacent the cathode region of glow discharge deposition apparatus, said apparatus adapted to deposit at least one layer of semiconductor material onto a substrate. The deposition apparatus includes at least one dedicated deposition chamber into which process gases are introduced for glow discharge disassociation into species. The system of the present invention includes a baffling manifold adjacent the cathode, said manifold adapted to (1) substantially prevent adjacent slowly and rapidly moving streams of process gases from forming flow patterns as the semiconductor material is deposited onto the substrate, and (2) thoroughly mix the process gases for only introducing homogeneous, uniform process gas mixtures into the plasma region, thereby preventing adjacent nonhomogeneous, nonuniform mixtures from forming flow patterns as the semiconductor material is deposited onto the substrate. The system is also adapted to expose the entire transverse width of the substrate for the deposition of semiconductor material thereunto.

Process gas introduction, confinement and evacuation system for glow

A process gas introduction and channeling system for use with apparatus adapted to produce photovoltaic devices by depositing semiconductor layers onto continuously moving substrate material. The deposition apparatus preferably includes at least one deposition chamber having (1) a region in which process gases are decomposed and (2) a manifold from which process gases are introduced to flow through the downstream decomposition region. In the preferred embodiment, as the process gases flow through the decomposition region, they are disassociated and recombined under the influence of an electromagnetic field. The species and combinations of process gases thus formed are deposited onto the substrate material. The process gas introduction and channeling system described herein, is adapted to direct the process gases introduced into each of the at least one deposition chamber to pass through the decomposition region thereof in a direction substantially parallel to the direction of travel of the substrate material, whereby substantially uniform semiconductor layers are deposited atop the entire surface of the substrate material.

Process gas introduction and channeling system to produce a profiled

A system for introducing, confining and evacuating process gases adjacent the cathode region of glow discharge deposition apparatus, said apparatus adapted to deposit at least one layer of semiconductor material onto a substrate. The deposition apparatus includes at least one dedicated deposition chamber into which process gases are introduced for glow discharge disassociation into species. The system of the present invention includes a baffling manifold adjacent the cathode, said manifold adapted to substantially reduce areas of localized rarification and compression of process gases flowing through the plasma region for substantially preventing adjacent stagnant and rapidly moving areas of process gases from forming nonuniform flow patterns as the semiconductor layer is deposited on the surface of the substrate. The system is also adapted to expose the entire transverse width of the substrate for the deposition of semiconductor material thereunto.

An improved magnetic gas gate is adapted to operatively interconnect two adjacent chambers, in the first chamber of which process gases are introduced for depositing a first layer upon a magnetic substrate and in the second chamber of which process gases are introduced for depositing a second layer atop the first layer. Since it is important to prevent the second chamber gases from contaminating the first chamber gases, a constant pressure differential established between the chambers is employed to provide a substantially unidirectional flow of gases from the first chamber into the second chamber. Magnetic gas gates have been used in the prior art to reduce the size of gas gate passageways by creating a magnetic field which urges the unlayered surface of the substrate toward a wall of the passageway. Although the size of the passageway opening is thereby reduced with a corresponding reduction in back diffusion of gases from the second chamber, the passageway is simultaneously divided into a relatively large flow channel and a relatively narrow flow channel. The present invention reduces the back diffusion of gases through the relatively narrow flow channel by forming a plurality of elongated grooves in the passageway wall toward which the unlayered surface of the substrate is urged. The grooves are substantially coextensive with the length of the passageway so as to operatively interconnect the adjacent chambers. The flow channels thus established are adapted to accommodate a sufficient flow of inert sweep gases to further reduce the back diffusion of process gases through the narrow flow channel.

Grooved gas gate

A grooved passageway surface in a magnetic gas gate, the gas gate adapted to operatively connect two adjacent chambers, in the first chamber of which process gases are introduced for depositing a first layer upon a magnetic substrate and in the second chamber of which process gases are introduced for depositing a second layer atop the first layer. Since it is important to prevent the second chamber gases from contaminating the first chamber gases, a constant pressure differential established between the chambers is employed to provide a substantially unidirectional flow of gases from the first chamber into the second chamber. Magnetic gas gates have been used in the prior art to reduce the size of gas gate passageways by creating a magnetic field which urges the unlayered surface of the substrate toward a wall of the passageway. Although, thereby reducing the size of the passageway opening and correspondingly reducing the back diffusion of gases from the second chamber, the passageway is simultaneously divided into a relatively large flow channel and a relatively narrow flow channel. The present invention is concerned with reducing the back diffusion of gases through the relatively narrow flow channel. This is accomplished by forming a plurality of elongated grooves in the passageway wall toward which the unlayered surface of the substrate is urged. The grooves are substantially coextensive with the length of the passageway so as to operatively interconnect the adjacent chambers. The flow channels thus established are able to accommodate a sufficient flow rate of process gases to further reduce the back diffusion of process gases.

Growing community of inventors

Sterling Heights, MI, United States of America

Kevin R Hoffman