MANUFACTURE OF COMPOUND SEMICONDUCTOR AND SEMICONDUCTOR CIRCUIT

摘要

Monolithic integration of Si MOSFETs (10) and gallium arsenide MESFETs (100) on a silicon substrate (12) is described herein. Except for contact openings and final metallization, the Si MOSFETs are first fabricated on selected areas of a silicon wafer. CVD or sputtering is employed to cover the wafer with successive layers (14 to 17) of SiO2 and Si3N4 to protect the MOSFET structure during gallium arsenide epitaxy and subsequent MESFET processing. Gallium arsenide layers are then grown by MBE or MOCVD or VPE over the entire wafer. The gallium arsenide grown on the bare silicon is single crystal material while that on the nitride is polycrystalline. The polycrystalline gallium arsenide is etched away and MESFETs (100) are fabricated in the single crystal regions by conventional processes. Next, the contact openings for the Si MOSFETs are etched through the Si3N4/SiO2 layers and final metallization is performed to complete the MOSFET fabrication. In an alternative embodiment, Si MOSFETs and aluminum gallium arsenide double heterostructure LEDs are formed in a similar manner.