Abstract: A method and apparatus are provided for producing fine quality pnictide films by vacuum evaporation and molecular beam deposition. A pnictide source, preferably phosphorous, is heated to produce a continuous supply of vapor species, preferably P.sub.4. The vapor species is cracked by a heated tungsten wire positioned adjacent the pnictide source to produce P.sub.2 molecules. A second tungsten wire cracker is located adjacent a substrate to prevent the recombination of P.sub.2 molecules into P.sub.4 molecules. The P.sub.2 molecules are deposited on the substrate and condense into amorphous pure phosphorous shiny red films. A separate source of alkali metal intercalate, preferably KC.sub.8, may also be heated to provide an alkali metal vapor for producing films of alkali metal polypnictide films, preferably KP.sub.x where x is equal to or greater than 15, to be deposited on the substrate.

Abstract: Fine quality catenated phosphorus thin films are produced in a high vacuum evaporator. Heated tungsten wire crackers are provided above the phosphorus boat and below the substrates. Amorphous pure phosphorus shiny red films have been deposited on glass, metallized glass and GaP and exhibit an optical edge at 2.0 eV. Films of KP.sub.x where x is equal to 15 or greater than 15 are produced by utilizing a second baffled boat source containing the potassium graphite intercalate, KC.sub.8. Addition of a nickel evaporation source provides nickel-doped polyphosphide films.

Abstract: Metal-insulator-semiconductor devices are formed on III-V semiconductors utilizing a pnictide rich insulating layer. The layer may be applied by vacuum evaporation, sputtering, chemical vapor deposition, and from a liquid melt. Gallium arsenide, indium phosphide, and gallium phosphide substrates are insulated with an alkali metal high pnictide polypnictide, preferably a polyphosphide, having the formula MP.sub.x where x is equal to or greater than 15, including new forms of phosphorus grown in the presence of an alkali metal where x is much greater than 15. A KP.sub.15 layer is preferred. They may also be insulated with a layer of a solid elemental pnictide, namely phosphorus, arsenic, antimony or bismuth applied by one of the above named processes. An elemental phosphorus layer is preferred. A silicon nitride, Si.sub.3 N.sub.4, layer may be added on top of the pnictide layer to increase the breakdown voltage of the insulating layer.