Method for in-situ cleaning of native oxide from silicon surfaces

A method of processing a silicon wafer, the wafer having a native oxide thereon, comprising:

• positioning said silicon wafer in a chemical vapor deposition chamber;
• evacuating said chamber until the chamber pressure is less than about 10.sup.-5 Torr of oxygen and water;
• flowing hydrogen and at least one other reducing gas selected from the group consisting of silane and dichlorosilane over the surface of said silicon wafer;
• thereafter, heating said silicon wafer to a wafer cleaning temperature of not higher than about 1025.degree. C. while continuing to flow hydrogen over the surface of said silicon wafer until an evaporation and a chemical reaction remove substantially all native oxide from the surface of the silicon wafer;
• and
• then forming a layer of silicon nitride on the surface of said silicon wafer without removing the wafer from said chamber by passing a mixture of dichlorosilane gas and ammonia gas over the surface of said silicon wafer at a deposition temperature not higher than said wafer cleaning temperature.