Abstract: A novel high speed, high quality plasma enhanced surface modification or CVD thin-film deposition method and apparatus. The invention employs both microwave and e-beam energy for creation of a plasma of excited species which modify the surface of substrates or are deposited onto substrates to form the desired thin film. The invention also employs a gas jet system to introduce the reacting species to the plasma. This gas jet system allows for higher deposition speed than conventional PECVD processes while maintaining the desired high quality of the deposited materials.

Abstract: A method of depositing, by microwave plasma enhanced chemical vapor deposition, a modified, silicon oxide, barrier coating atop a temperature sensitive substrate; said barrier coating having barrier properties to at least gaseous oxygen and water vapor. The precursor gaseous mixture includes at least a silicon-hydrogen containing gas, an oxygen containing gas and a gas containing at least one element selected from the group consisting of germanium, tin, phosphorus, and boron. The method requires introducing a sufficient flow rate of oxygen-containing gas into the precursor gaseous mixture to eliminate the inclusion of silicon-hydrogen bonds into the deposited coating. The preferred modifier is germanium. Also, a composite material having a microwave-plasma-enhanced-chemical-vapor-deposited silicon oxide (modified or non-modified) barrier coating. The barrier coating has barrier properties to at least gaseous oxygen and water vapor and is substantially free of Si--H bonds.

Abstract: Apparatus for the simultaneous plasma assisted chemical vapor deposition of thin film material onto an elongated web of substrate material at a plurality of discrete spatially separated deposition zones. In order to accomplish said simultaneous deposition, the web of substrate material is operatively positioned so as to assume a serpentine path of travel through a reduced pressure enclosure. By using an elongated linear applicator as a source of microwave energy, a high rate of uniform deposition of said thin film material over a plurality of large areas of the web of substrate material can be simultaneously achieved without heating of said web above the melting point thereof. In a preferred embodiment, the web of substrate material is formed of a low temperature, microwave transmissive synthetic plastic resin and the thin film material deposited thereupon forms a barrier coating for preventing oxygen diffusion therethrough.

Abstract: An amorphous semiconductor body, preferably a silicon-containing vapor deposited film, is provided containing at least fluorine as a compensating or altering and also an alloying agent, and most preferably at least one complementary compensating or altering agent, which reduce the localized defect states in the energy gap of the amorphous semiconductor material to a degree which either one alone could not achieve. As a result, the amorphous semiconductor body provides a higher photoconductivity, wider depletion width, more efficient charge carrier collection, longer carrier lifetime, and lower dark intrinsic electrical conductivity, where desired, and can be more easily modified to shift the Fermi level to provide very efficient n type extrinsic electrical conductivity and the like than prior amorphous semiconductor bodies.

Abstract: A method of making a photovoltaic panel which includes the continuous deposition of silicon films onto a continuously moving substrate web.

Abstract: Apparatus for and a method of confining the ionized plasma developed during the glow discharge deposition of thin film semiconductor alloy material to preselected portions of the plasma region so as to prevent etching and deposit only uniform, nonhomogeneous semiconductor alloy material.

Abstract: An improved large area photovoltaic device includes a plurality of electrically interconnected smaller area cells. The smaller area cells each have a laterally disposed bus bar and are disposed in overlapping relationships so that the bus bar of a given cell is beneath the substrate of the adjacent overlapping cell. In this manner the surface of the resulting large area device available for photovoltaic power generation is maximized. Also disclosed herein are methods for the manufacture of the improved device.

Abstract: An improved cathode assembly specifically designed to provide for the uniform, localized profiling of dopant or other alterant elements into the host matrix of a semiconductor alloy material which is continuously and uniformly deposited onto a moving substrate by a glow discharge deposition process.

Abstract: An amorphous semiconductor body, preferably a silicon-containing vapor deposited film, is provided containing at least fluorine as a compensating or altering and also an alloying agent, and most preferably at least one complementary compensating or altering agent, which reduce the localized defect states in the energy gap of the amorphous semiconductor material to a degree which either one alone could not achieve. As a result, the amorphous semiconductor body provides a higher photoconductivity, wider depletion width, more efficient change carrier collection, longer carrier lifetime, and lower dark intrinsic electrical conductivity, where desired, and can be more easily modified to shift the Fermi level to provide very efficient n type extrinsic electrical conductivity and the like than prior amorphous semiconductor bodies.

Abstract: An improved semiconductor device, adapted to provide electrical current in response to light energy incident thereon, includes a first electrode, an active semiconductor body atop the first electrode, a second electrode atop the semiconductor body, and at least one defect region which is capable of providing a low resistance shunt path for the flow of electrical current between the electrodes of the device. The improvement comprises a continuous transparent barrier layer (1) operatively disposed between the semiconductor body and one of the electrodes of the device and (2) adapted to decrease the flow of electrical current through the at least one defect region of the semiconductor device. The barrier layer is formed from a material chosen from the group consisting essentially of oxides, nitride and carbides of: indium, tin, cadmium, zinc, antimony, silicon, chromium and mixtures thereof.

Abstract: An electroplated substrate, characterized by a substantially reduced number of surface defects, for the fabrication of thin film electronic devices. The substrate is prepared in an electroforming process by electroplating onto and removing a metallic layer from the surface of a specifically prepared, substantially defect-free mandril. The substrate may be provided with a preselected surface finish by either (1) texturing the mandril or (2) controlling the parameters of the electroplating process to control the morphology of the deposit. The substrate is especially adapted for the fabrication of thin film photoresponsive devices which incorporate specular or diffuse back reflectors, since the texture may be controlled to provide for the appropriate type of reflectivity. Large area, thin film semiconductor devices incorporating the electroplated substrate are readily scribed to form electrically isolated small area segments for the fabrication of modules, arrays and the like.

Abstract: A valve for isolating the interior of a glow discharge chamber from the atmosphere and other reactants. The valve includes a body mounted in an aperture of the chamber. A slit-like opening is provided therein to allow the interior of the chamber to communicate with interrelated elements of a deposition system. A source is provided for introducing inert gas into the opening under pressure somewhat greater than that of reaction gases and plasma within the chamber to create an effective, non-reactive gas curtain.

Abstract: A continuous system for depositing at least one layer of amorphous semiconductor material upon a substrate. Feed and takeup sections provide reel-to-reel advancement of a thin film substrate through the system. At least one chamber is located between the feed and takeup sections. A plasma is generated therein by glow discharge decomposition of an appropriate mixture of reaction gases. Apparatus associated with the chamber allows the close regulation of the plasma/substrate surface equilibrium to assure the deposition of a uniform layer of amorphous material. At least one servocontrolled reel drive regulates the tension of the web-like substrate as it advances to avoid cracking and to assure its proper registration with a mask comprising a plurality of strips. A curtain of inert gas provides isolation between the interior of each chamber and the environment.

Abstract: An improved semiconductor device, adapted to provide electrical current in response to light energy incident thereon, includes a first electrode, an active semiconductor body atop the first electrode, a second electrode atop the semiconductor body, and at least one defect region which is capable of providing a low resistance shunt path for the flow of electrical current between the electrodes of the device. The improvement comprises a continuous transparent barrier layer (1) operatively disposed between the semiconductor body and one of the electrodes of the device and (2) adapted to decrease the flow of electrical current through the at least one defect region of the semiconductor device. The barrier layer is formed from a magnesium fluoride based material. Methods of (1) fabricating improved semiconductor devices and (2) preventing operational mode failures due to latent detents are also disclosed.

Abstract: An electroplated substrate, characterized by a substantially reduced number of surface defects, for the fabrication of thin film electronic devices. The substrate is prepared in an electroforming process by electroplating onto and removing a metallic layer from the surface of a specifically prepared, substantially defect-free mandril. The substrate may be provided with a preselected surface finish by either (1) texturing the mandril or (2) controlling the parameters of the electroplating process to control the morphology of the deposit. The substrate is especially adapted for the fabrication of thin film photoresponsive devices which incorporate specular or diffuse back reflectors, since the texture may be controlled to provide for the appropriate type of reflectivity. Large area, thin film semiconductor devices incorporating the electroplated substrate are readily scribed to form electrically isolated small area segments for the fabrication of modules, arrays and the like.

Abstract: The production of improved photoresponsive amorphous alloys and devices, such as photovoltaic, photoreceptive devices and the like; having improved wavelength threshold characteristics is made possible by adding one or more band gap adjusting elements to the alloys and devices. The adjusting element or elements are added at least to the active photoresponsive regions of amorphous devices containing silicone and fluorine, and preferably hydrogen. One adjusting element is germanium which narrows the band gap from that of the materials without the adjusting element incorporated therein. Other adjusting elements can be used such as tin. The silicon and adjusting elements are concurrently combined and deposited as amorphous alloys by vapor deposition, sputtering or glow discharge decomposition. The addition of fluorine bonding and electronegativity to the alloy acts as a compensating or altering element to reduce the density of states in the energy gap thereof.

Abstract: The continuous production of solar cells by the glow discharge (plasma) deposition of layers of varying electrical characteristics is achieved by advancing a substrate through a succession of deposition chambers. Each of the chambers is dedicated to a specific material type deposition. The chambers are mutually isolated to avoid the undesired admixture of reaction gases therebetween. Each plasma deposition is carried out in its glow discharge area, chamber, or chambers, with isolation between the plasma regions dedicated to different material types. Masking, mechanical or lithographic, can be employed relative to the substrate to cause the deposition in the desired configuration. After the semiconductor deposition is complete, top contact and anti-reflection layer or layers are deposited, followed by a protective lamination.

Abstract: An upstream cathode system for use with glow discharge deposition apparatus, said apparatus adapted for the production of large area photovoltaic devices. In such apparatus, process gases are commonly introduced into a deposition chamber from a gas manifold disposed on the upstream side of a substrate. As the process gases are drawn across the surface of the substrate, they are continuously disassociated and recombined under the influence of an electromagnetic field developed by a deposition cathode or microwave generator. By providing a precathode system, upstream of the deposition cathode or microwave generator, (1) impurities in the process gases, (2) contaminants from the walls of the deposition chamber and (3) initially disassociated and recombined process gas compositions may be deposited onto and collected from a collection plate disposed upstream of the substrate.

Abstract: A composite substrate for the fabrication of thin film electronic devices. The substrate is a multi-layer structure which includes (1) a support layer having sufficient rigidity to provide structural strength for the subsequently deposited semiconductor material and/or circuit elements, and (2) an electrically insulating layer for providing electrical isolation in both the vertical and horizontal directions. In a preferred embodiment wherein the electronic device is formed as a solar cell, the insulating layer of the composite substrate may be provided with a texturized surface to form a diffuse, light reflecting surface. Also disclosed herein is a process for fabricating the multi-layer, back reflecting composite substrate of the instant invention.

Abstract: Systems and methods for detecting and eliminating short circuit current paths through photovoltaic devices of the type including at least one semiconductor region overlying a substrate and a layer of conductive light transmissive material overlying the at least one semiconductor region are disclosed. The short circuit current paths which are eliminated extend through the at least one semiconductor region from the substrate to the layer of conductive light transmissive material. The resistivity of the short circuit current path is increased substantially at the interface between the conductive light transmissive material and the semiconductor region by isolating electrically the conductive light transmissive material from the short circuit current path.The isolation can be provided by removing the transparent conductive material from electrical contact or connection with the short circuit current path.