Double-Sided Silicon Nitride Deposition of Wafers
Original Publication Date: 1985-Jul-01
Included in the Prior Art Database: 2005-Feb-19
Silicon nitride is deposited on both sides of a wafer to achieve two process goals simultaneously. The frontside allows for the formation of a substrate contact, and the backside for gettering. The process goals are realized because the frontside deposition is used as a self-aligned mask to define two ion-implanted device structures using only one photo mask. The backside nitride deposition, which remains on the wafer throughout the process, maximizes impurity gettering. The backside implant technique is used as a means for gettering impurities away from active device regions and from being incorporated into the oxide layers.