Abstract: Group III-V compound semiconductor devices with attached gold conductor areas are etched using a basic ferricyanide etchant. The etchant is an aqueous solution containing ferricyanide ions in a concentration from 0.8 molar to 1.2 molar and sodium or potassium hydroxide in a concentration from 0.3 molar to 1.5 molar. This etchant rapidly removes the semiconductor material leaving smooth surfaces, while leaving the gold conductors and areas protected by oxide layers essentially intact. The use of titanium layers as etching masks, deposited for example by evaporating or sputtering through a removable mask, is also disclosed.

Abstract: Certain copper-nickel-tin alloys falling within a single phase region at temperatures approaching the melting point, but within a two-phase region at room temperature, when pretreated to produce a supersaturated single phase structure having a medium to fine grain size, followed by cold working to at least 75 percent area reduction and concluding with a critical aging treatment determined by the alloy composition and by the extent of prior cold working, exhibit higher mechanical strengths for given levels of ductility than have heretofore been attained for copper alloys. The alloys of the invention are useful in a variety of applications requiring a combination of properties including mechanical strengths, ductility, electrical conductivity and corrosion resistance, and are particularly useful as springs, relay elements, wire connectors and other similar flexible articles.

Abstract: A heat storage device of simple design and compact dimensions is disclosed. The device uses a heat storage medium which contracts upon melting and which has a melting point high enough to be of use in connection with conventional, nuclear, and solar power plants.

Abstract: A method is disclosed for fabricating an optical fiber by drawing a preform whose manufacture involves the deposition of a borosilicate layer. The method calls for borosilicate deposition by high temperature pyrolysis of two gases, with processing parameters chosen so as to cause an acicular structure in the deposited layer, a structure which contributes to the uniformity of the drawn fiber.