Abstract: A polycrystalline silicon film formed of an active layer of a thin film transistor is entirely hydrogenated by a low-temperature process, thereby lowering the resistance and relaxing the electric field in the vicinity of the drain to reduce the leakage current. A gate and an insulating film that covers it are formed on a substrate having an insulating surface. A hydrogenated polycrystalline silicon film is formed over the substrate, including the gate, with the insulating film interposed therebetween. A silicon oxide film pattern is formed on the polycrystalline silicon film directly above the gate. Source/drain regions are formed on the polycrystalline silicon film substantially at two external sides of the silicon oxide film pattern. The source/drain regions are formed from a hydrogen-containing amorphous silicon film, a conductive silicon film and a metal film, which are successively stacked on the polycrystalline silicon film.

Abstract: An active layer of an insulated-gate type field effect transistor is formed by a thin film of an intrinsic polycrystalline semiconductor and a source electrode and a drain electrode are formed on the active layer. A source region and a drain region are not formed in the active layer. A main gate electrode is formed on a gate insulating film of a portion between the source electrode and the drain electrode. Subgate electrodes are formed on the gate insulating film in a portion between the source electrode and the main gate electrode and a portion between the drain electrode and the main gate electrode, respectively.

Abstract: Disclosed herein is a solar cell which is composed basically of a first semiconductor layer of first conductivity type, a second semiconductor layer of second conductivity type, and a third semiconductor layer formed between them. The third semiconductor layer has a band gap narrower than that of the first and second semiconductor layers. The third semiconductor layer also has a pn junction therein. The semiconductor layers are each separated by a buffer layer in which the composition changes gradually across the thickness so that the lattice mismatch between the semiconductor layers is relieved.

Abstract: A thin semiconductor film having at least one an edge is formed on a base whose material is different from the material of the thin semiconductor film. A laser beam, for example, is applied to the semiconductor film thereby to melt the semiconductor film including the edge for thereby beading the edge upwardly. The melted semiconductor film including the edge is solidified and hence recrystallized into a semiconductor crystal. A plurality of spaced reflecting films may be formed on the thin semiconductor film before the laser beam is applied. Various semiconductor devices including a thin-film transistor, a solar cell, and a bipolar transistor may be fabricated of the semiconductor crystal.

Abstract: An integrated circuit is formed thereof a conductive wiring pattern. On the conductive wiring semiconductor layer is directly formed in a form of amorphous on the substrate. The amorphous semiconductor layer is annealed to form a polycrystalline structure while avoiding influence of annealing heat for the substrate. In the polycrystalline semiconductor layer is formed a semiconductor element, such as MOS transistor, MIS transistor, TFT and so forth. The semiconductor element is directly connected to the wiring pattern on the substrate.

Abstract: A plasma system which eliminates damage derived from charged particles in the plasma and which is able to perform uniform plasma CVD and plasma etching on a large area substrate, wherein a mesh plate having a plurality of holes is placed at the interface of a plasma generation chamber and a substrate treatment chamber which holds a substrate, a high frequency electrical field being applied between an upper electrode in the plasma generation chamber and the mesh plate so as to disassociate the plasma forming gas by electrodischarge so as to cause the generation of plasma. By this, the plasma is isolated from the substrate. On the other hand, source gas supply ports are opened near the holes of the mesh plate, the source gas being introduced from there being brought into contact with the plasma through the holes, whereby the reaction product can be uniformly produced in a broad area.

Abstract: A method of crystallizing a semiconductor thin film moves a laser beam emitted by a pulse laser in a first direction to irradiate the semiconductor tin film with the laser beam for scanning. The laser beam is split into a plurality of secondary laser beams of a width smaller than the pitch of step feed, respectively having different energy densities forming a stepped energy density distribution decreasing from the middle toward the opposite ends thereof with respect to the direction of step feed. The energy density of the first secondary laser beam corresponding to the middle of the energy distribution is higher than a threshold energy density, i.e., the minimum energy density that will melt the semiconductor thin film to make the same amorphous, and lower than a roughening energy density, i.e.

Abstract: Seed crystals are made in a region of a polycrystalline layer on a substrate using a beam of electrons. The beam is used to melt the region, which is then solidified from one end to the other in a first direction and outwardly toward the edges in a second direction normal to the first direction. Several different techniques can be used to promote solidification in the proper directions. The region can be heated non-uniformly and then cooled to maintain the desired temperature distribution. The region can also be cooled non-uniformly to provide the desired temperature distribution. The region can be heated non-uniformly using apparatus that controls the energy deposited in the region by the electron beam.

Abstract: A large, single-crystal semiconductor device is made from a substrate having a layer of polycrystalline or amorphous material thereon by exposing a region of the layer to a beam of electrons to melt the region and then solidifying the molten region from one end to the other in a first direction and outwardly toward the edges in a second direction normal to the first direction to form a single-crystal seed in the region. An operating layer of polycrystalline or amorphous material on the substrate in contact with the seed is scanned with a beam of electrons having a strip-like configuration. The beam remelts a portion of the seed and creates a molten zone in the layer that recrystallizes as a single crystal by lateral epitaxial recrystallization from the seed.

Abstract: Seed crystals are made in a region of a polycrystalline layer on a substrate by melting the region and then cooling it so that it solidifies from one end to the other in a first direction and outwardly toward the edges in a second direction normal to the first direction. The desired cooling pattern is established by providing a thermal layer under the polycrystalline layer, which thermal layer is used to provide different rates of heat conduction therethrough in different parts of the thermal layer. A large, single-crystal device can be made by providing an operating layer of polycrystalline material in contact with the seed, melting the operating layer and recrystallizing it so that its solidification proceeds from the seed. The thermal layer can be used to ensure the desired direction of resolidification by providing different rates of heat conduction therethrough in different parts of the thermal layer.