N-type buried layer drive-in recipe to reduce pits over buried antimony layer

摘要

A method of driving-in antimony into a wafer, including the following steps. A wafer is loaded into an annealing furnace/tool. The wafer having an area of implanted antimony ions. The wafer is annealed a first time at a first temperature in the presence of only a first nitrogen gas flow rate. The wafer is ramped-down from the first temperature to a second temperature in the presence of only an oxygen gas flow rate. The wafer is maintained in the presence of the of oxygen gas flow rate at the second temperature. The wafer is ramped-up from the second temperature to a third temperature in the presence of only the oxygen gas flow rate. The wafer is annealed a second time at the third temperature in the presence of only a second nitrogen gas flow rate to drive-in the antimony ions within the area of implanted antimony.