A film of an insulating compound is formed by evaporating the individual elements from separate sources while maintaining the substrate at a temperature in the range in which neither element will deposit if evaporated alone. A baffle disposed between the sources and the substrate prevents other than vaporized material from reaching the substrate. The film is very pure, may be highly oriented when formed on a suitable substrate, and is particularly useful for its piezoelectric properties.
A method for depositing thin films of gold having a high degree of orientation on surfaces previously yielding only unoriented gold by sputtering a layer of glass over the surface of the material followed by depositing a layer of oriented gold over the layer of glass. The additional step of depositing a layer of piezoelectric material over the layer of oriented gold is included to provide piezoelectric material having good orientation due to the oriented gold. A transducer is described having a layer of glass deposited over a material which previously provided unoriented gold followed by a layer of gold, a layer of piezoelectric material and a top conductive electrode to form a transducer wherein the piezoelectric material has a high degree of orientation.
This invention relates to a process for preparing a vitreous semiconductor comprising bismuth and selenium. The semiconductor has at least 0.5 atomic percent bismuth and a greater than a stoichiometric percentage of selenium. The invention also relates to a method for producing such a semiconductor by co-evaporating the bismuth and selenium and simultaneously quenching the metal and non-metal vapors onto a substrate held at a temperature below the condensation point of either component.
A transducer with thin films of gold having a high degree of orientation on surfaces previously yielding only unoriented gold has a layer of glass over the surface of the substrate material followed by a layer of oriented gold over the layer of glass. The added layer of piezoelectric material over the layer of oriented gold provides piezoelectric material having good orientation due to the oriented gold. Addition of a top conductive electrode forms a transducer wherein the piezoelectric material has a high degree of orientation.
A method and an apparatus for forming a thin film are provided to achieve precise control of a film thickness. In a thin film forming apparatus a shutter provided between a target and a substrate is rotated a plurality of times during a film forming process so that a slit of the shutter passes between the target and the substrate a plurality of times. A thin film forming substance thereby arrives at the substrate from the target a plurality of times in an intermittent manner. A thin film having a predetermined thickness is thus formed on the substrate.
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.
