Patent ID: 6929831

Claim:
A method of depositing a silicon nitride capping layer, said method including; placing a gallium arsenide (GaAs) substrate which includes a non-activated implant into a chamber; pre-cleaning the surface of the GaAs substrate using a H 2 plasma; and introducing into a plasma region of the chamber a silicon containing gas, molecular nitrogen and sufficient hydrogen to dissociate the nitrogen to allow the silicon and nitrogen to react to form a silicon nitride capping layer of at least 400 nanometers in thickness on a surface of the GaAs substrate which includes the non-activated implant adjacent the plasma region, wherein a flow rate of the nitrogen is in the range 700-900 sccm and a flow rate of the hydrogen is 500-800 sccm, and wherein a power supplied to the plasma is between 50 and 150 W.