FABRICATION OF SEMICONDUCTOR MATERIALS AND DEVICES WITH CONTROLLED ELECTRICAL CONDUCTIVITY

摘要

A METHOD FOR PROTECTING THE SURFACE OF A SEMICONDUCTOR MATERIAL (30,50) FROM DAMAGE AND DOPANT PASSIVATION IS DESCRIBED. P BARRIER LAYER (32,52) OF DENSE OR REACTIVE MATERIAL IS DEPOSITED ON THE SEMICONDUCTOR MATERIAL SHORTLY AFTER GROWTH IN A GROWTH REACTOR (10) SUCH AS A MOCVD REACTOR, USING THE MOCVD SOURCE GASSES. THE BARRIER LAYER (32,52) BLOCKS THE DIFFUSION OF HYDROGEN INTO THE TAATERIALA THE REACTOR (10) CAN THEN BE COOLED IN A. REAÖTIVE OR NONREACTIVE GAS AMBIENCE. THE SEMICONDUCTOR MATERIAL CAN THEN BE REMOVED FROM THE REACTOR (10) WITH LITTLE OR RIO PASSIVATION OF THE DOPANT SPECIES. THE BARRIER LAYER (32,52) CAN BE REMOVED USING A V RIETY : OF ETCHING PROCESSES, INCLUDING WET CHEMICAL ETCHING OR CAN BE LEFT AT THE SEMICONDUCTOR MATERIAL FOR SURFACE PROTECTION. THE BARRIER LAYER (32,52) CAN ALSO BE A GETTERIN LAYER THAT CHEMICALLY BIND HYDROGEN TRAPPED IN THE SEMICONDUCTOR MATERIAL AND/OR BLOCKS HYDROGEN DIFFUSION INTO THE MATERIAL.