Abstract: In a method of producing a solar cell, a photovoltaic thin semiconductor crystalline film is formed on an underlying substrate and hydrogen passivated throughout the film thickness direction of the photovoltaic film whereby a high efficiency solar cell is obtained. In addition, since the passivation process is performed before forming a rear surface electrode on the thin semiconductor crystalline film, the passivation process is not limited by the rear surface electrode. Thereby, a solar cell having a higher energy conversion efficiency is obtained. The passivation process is performed by exposing the thin semiconductor crystalline film to a hydrogen ion ambient having a low acceleration energy, below 2 KeV, or to a plasma ambient. Therefore, the uniformity of the passivation process at a wafer surface is improved and a large area wafer can be efficient processed.

Abstract: A process for the production of a solar cell, characterized in that the surface of a silicon wafer is periodically exposed through minute spaced portions of an insulating layer formed on the silicon wafer; crystal growth is performed until monocrystalline silicon regions caused at the spaced portions by way of selective epitaxial growth and lateral crystal growth become collided with each other; the insulating layer is removed through gaps left among the monocrystals; a resin is embedded in the gaps; an electrode layer is formed over the surfaces of the monocrystalline silicon regions; the surface of the electrode layer is fastened to a substrate through a resin; a body comprising the monocrystalline silicon regions is separated from the silicon wafer; and a counter electrode is disposed to the monocrystalline silicon regions.

Abstract: A I-III-VI.sub.2 chalcopyrite semiconductor film containing a Group VII element as a dopant, and methods to produce such a chalcopyrite film are provided. The chalcopyrite film of the present invention has stoichiometric composition, and electrical characteristics such as p-n conduction type, carrier concentration and the like are controlled.

Abstract: A two-step back-side hydrogenation process includes the steps of first bombarding the back side of the silicon substrate with hydrogen ions with intensities and for a time sufficient to implant enough hydrogen atoms into the silicon substrate to potentially passivate substantially all of the defects and impurities in the silicon substrate, and then illuminating the silicon substrate with electromagnetic radiation to activate the implanted hydrogen, so that it can passivate the defects and impurities in the substrate. The illumination step also annihilates the hydrogen-induced defects. The illumination step is carried out according to a two-stage illumination schedule, the first or low-power stage of which subjects the substrate to electromagnetic radiation that has sufficient intensity to activate the implanted hydrogen, yet not drive the hydrogen from the substrate.

Abstract: A thin film transistor and a photovoltaic cell wherein a polycrystalline semiconductive film, having a large grain size and high carrier mobility obtained by heat treatment of a polycrystalline semiconductive film, an amorphous semiconductive film, a microcrystalline semiconductive film or the like on a substrate with a textured surface, is used as a channel layer or a photo-activation layer, the textured surface being formed by etching one surface of the substrate or forming a textured thin film on the substrate.A method of manufacturing a polycrystalline semiconductive film, wherein a surface of a substrate is etched or a textured thin film is formed on the substrate to form a textured surface, and a polycrystalline semiconductive film, an amorphous semiconductive film, a microcrystalline semiconductive film or the like is formed on the textured surface, and the semiconductive film is polycrystallized by heat treatment.

Abstract: A solar cell fabrication procedure is described in which an excimer laser is used to cut a trench in a flat solar cell substrate so as to electrically isolate front and back regions of the substrate. The trench is cut around the perimeter of the cell. The advantage of using an excimer laser is that it will ablate a trench without diffusing conductive material deeper into the cell.

Abstract: Semiconductor layers having a p-n junction are formed over the surface of a semiconductor substrate except for a partial surface. On the partial surface of the semiconductor substrate, a region of an electrode to be connected with an external terminal is formed with an insulating film interposed between the same. Bonding connection with the external terminal is performed on the region for connection, to reduce mechanical damage of the semiconductor layers having the p-n junction while improving photoelectric conversion efficiency and reliability of the device.

Abstract: A technique is disclosed forming thin films (13) of group IIB metal-telluride, such as Cd.sub.x Zn.sub.1-x Te (0.ltoreq.x.ltoreq.1), on a substrate (10) which comprises depositing Te (18) and at least one of the elements (19) of Cd, Zn, and Hg onto a substrate and then heating the elements to form the telluride. A technique is also provided for doping this material by chemically forming a thin layer of a dopant on the surface of the unreacted elements and then heating the elements along with the layer of dopant.

Abstract: A method of manufacturing a photovoltaic device, in which a plurality of photoelectric conversion elements comprising a first electrode layer, a semiconductive layer and a second electrode layer are laminatedly arranged on an insulative surface of a substrate and said photoelectric conversion elements are electrically connected in series with each other, comprising a step of dividedly arranging the first electrode layer on the surface of the substrate, a step of coating the semiconductive layer on the surface of the substrate including the upper surface of the divided first electrode layer, a step of coating the second electrode layer on the semiconductive layer, and a step of dividing the semiconductive layer and/or the second electrode layer in order to define each element by irradiating energy-beams on the semiconductive layer and/or the second electrode layer.

Abstract: A method for the manufacture of gallium arsenide thin film solar cells on inexpensive substrate material whereby an intermediate layer of highly doped, amorphous germanium is employed in order to promote the growth of the gallium arsenide layers. A high-energy radiation is directed to specific, prescribed points on the highly doped, amorphous germanium layer thereby generating centers having a defined crystal orientation, so that the epitaxial layer spreads laterally from these centers in a surface-covering fashion during the epitaxial vapor phase deposition. The solar cells produced by designational grain growth can be manufactured with high purity in a simple way and have an efficiency (greater than 20%) comparable to known mono-crystalline solar cells.

Abstract: A process is disclosed for fabricating an improved antireflection coating on a substrate. A layer of dielectric material having a first thickness and a first index of refraction are formed overlying a substrate. The dielectric material is implanted with hydrogen to form an implanted surface region having a thickness less than the thickness of the entire layer of dielectric material. The hydrogen reduces the index of refraction of the implanted region to a value less than the index of refraction of the initial layer. The structure overlying the substrate thus includes two integral layers having different indices of refraction with the lower index of refraction, as desired, at the surface of the dielectric material. The process can be extended by further implantation to provide an increased number of distinct layers of differing index or to provide a continuum of regions of varying index of refraction.