Abstract: A transparent substrate as formed on its front side a layer of amorphous silicon. A laser beam is used to irradiate through the backside of the transparent substrate in order to form buried nucleation sites within the amorphous silicon. The buried nucleation sites which are used as nucleation seeds are then used during a front side crystallization process in order to form large single silicon crystals over the substrate surface.

Abstract: The invention provides a buffered substrate that includes a substrate, a buffer layer and a silicon layer. The buffer layer is disposed between the substrate and the silicon layer. The buffer layer has a melting point higher than a melting point of the substrate. A polycrystalline silicon layer is formed by crystallizing the silicon layer using a laser beam.

Abstract: A low temperature process for dehydrogenating amorphous silicon using lasers. Dehydrogenation occurs by irradiating one or more areas of a hydrogenated amorphous silicon layer with laser beam pulses at a relatively low energy density. After the multiple laser pulse irradiation at a relatively low energy density, the laser energy density is increased and multiple irradiation at a higher energy density is performed. If after the multiple irradiation at the higher energy density the amorphous silicon hydrogen content is still too high, dehydrogenation proceeds by multiple irradiations at a yet higher energy density. The irradiation at the various energy densities can result in the formation of polysilicon due to melting of the amorphous silicon layer. As irradiation may be selectively applied to the amorphous silicon, an integral amorphous silicon-polysilicon structure may be formed.

Abstract: Deposition of continuous pin-hole free tellurium films with thicknesses to less than 150A on a suitable substrate is achieved by first pretreating the substrate prior to film deposition. Ion sputtering or bombardment of the substrate surface with an inert gas prior to tellurium evaporation creates a dense coverage of nucleation sites on the substrate which improves the adhesiveness and resistance to abrasion and oxidation of the deposited film while providing very thin pinhole free films of uniform thickness and desired crystallite orientation.

Abstract: To facilitate the ion bombardment of a substrate surface as a pretreatment step prior to depositing thin films in a high vacuum evaporation system, a thermionic electron source is placed in the cathode electrode used to generate the plasma that provides the ion bombardment. The thermionic electron source does not interfere with the basic function of the plasma system. Its main effect is to enhance the plasma efficiency by injecting electrons into the surrounding space, reducing charging effects on surfaces, neutralizing the plasma cloud, causing less plasma dispersion, and perhaps, most importantly, allowing the plasma to be sustained at lower pressures and higher voltages resulting in greater ion energies and mobility for improved surface bombardment.Other electron sources, such as, a cathode ray accelerator as a beta emitter, may be positioned to simultaneously or independently, to inject electrons into the plasma and to direct electrons toward the substrate surface to neutralize surface charge.

Abstract: A method of making thin film devices with selective etchants. Specifically, a fabrication process in accordance with the invention provides for the manufacture of amorphous chalcogenide sandwich structures. Such structures consist of a glass substrate, a chromium or aluminum electrode on the substrate bounding one side of the chalcogenide layer, and a second electrode of aluminum bounding the other side of the chalcogenide layer. First, the aluminum electrode is etched without affecting the other layers. Secondly, the chalcogenide layer is etched with a solution which attacks only the chalcogenide material and neither the overlying aluminum nor the underlying chromium or aluminum electrode. This two-step process is particularly suitable for fabricating current controlled negative differential resistance devices which requires the precise registration of one of the electrodes with the boundary of the chalcogenide such that a coextensive boundary is achieved.