Development of a System to Produce Semiconductor Insulator Multi-Layer Structures,

The development of Silicon-on-Sapphire SOS and Silicon-on-Insulator SOI technologies has led to applications of these technologies in high speed circuits, high density circuits, circuits with freedom from 4-layer latch-up, and radiation hard circuits. There has been significant effort aimed at commercialization of these processes. One of the major problems limiting wide spread use of SOS is the high cost of the sapphire substrate. Many attempts to produce lower cost SOI substrates using ion implantation of insulating materials and various annealing techniques to improve the crystallinity of poly crystal silicon layers have been attempted. An alternate technique to produce SOI materials has been to grow multiple heteroepitaxial silicon-insulator-silicon layers on silicon or sapphire substrates and use these layers for the fabrication of integrated circuits. Several insulators have been used in these structures. There is a continuing search for an optimum insulator to use in multiple silicon-insulator structures. One insulator that has been used for these multiple heteroepitaxial layers is boron phosphide. The purpose of the present work was to design and build an epitaxial reactor capable of growing silicon and boron phosphide layers on silicon and sapphire substrates and to use this reactor to grow layers of silicon and boron phosphide on silicon substrates.