US 5,326,424 A · Cubic boron nitride phosphide films

Abstract

Thin films of single crystal, cubic boron nitride phosphide are provided on, and in crystallographic registry with, an underlying silicon substrate which is oriented along a single crystallographic axis. The cubic boron nitride phosphide films are deposited using laser ablation methods. The boron nitride phosphide film has a crystallographic lattice constant which can be systematically varied depending upon the desired film composition and processing parameters. Preferably, the target, and accordingly the resulting thin film composition, is characterized by a chemical formula of BN.sub.(1-x) P.sub.(x) where x is about 0.23. This particular composition results in a crystallographic lattice constant essentially equal to the single crystal silicon substrate. The film may also have the formula BN1-xPx where x<0.ltoreq.1. The phosphorus concentration may also be decreased to zero throughout the film so as to provide boron nitride material at the surface, which is characterized by a good crystallographic lattice match with the underlying substrate. The resulting films are particularly suitable for semiconducting applications over a wide range of temperatures.

Claims12

Dependent claims

A method for forming thin films of crystalline cub boron nitride phosphide comprising the following steps:

providing a silicon substrate oriented essentially throughout along the (100) crystallographic axis of the substrate;
providing a target comprising hexagonal boron nitride and boron phosphide, said target being disposed in proximity with said silicon substrate;
inducing vaporization of said target using a pulsed excimer laser operating at parameters sufficient to dissociate and vaporize said hexagonal boron nitride/boron phosphide target to atoms/ions;
heating said substrate to a temperature sufficient to sustain crystal growth, such that the vaporized boron, nitrogen and phosphorus atoms/ions deposit onto a surface of said silicon substrate to form a thin film layer of crystalline cubic boron nitride phosphide.

1 more element

Dependencies are inferred from the claim text.

Cubic boron nitride phosphide films

Life of this patent

Cubic boron nitride phosphide films

Life of this patent

Abstract

Claims12