Method for improving gate oxide integrity using low temperature oxidation during source/drain anneal

Abstract

A method of annealing a partially fabricated semiconductor device which comprises the steps of annealing a partially fabricated semiconductor device in an atmosphere of an inert gas and an oxidizing gas. The inert gas is preferably one of nitrogen and argon and the oxidizing gas is preferably one or more of oxygen, hydrogen chloride and nitrogen trifluoride. The oxidizing gas is from about 1 to about 10% by volume of the atmosphere. The annealing step comprises maintaining the partially fabricated semiconductor device at a first temperature, preferably about 700.degree. C., for a first time period, preferably about 20 minutes, ramping up the temperature at a rate to a second temperature, preferably about 800.degree. C., maintaining the second temperature for a second time period, preferably about 20 minutes, ramping up the temperature at a rate, preferably about 10.degree. C./minute, to a third temperature, preferably about 900.degree. C. maintaining the third temperature for a third time period, preferably about 45 minutes, ramping down the temperature at a rate, preferably about 3.degree. C./minute, to a fourth temperature, preferably about 800.degree. then maintaining the fourth temperature for a fourth time period while maintaining the oxidizing gas in the atmosphere only during at least one of the first time period, the first ramping up, the second time period, the second ramping up, the ramping down or the fourth time period.

Dependencies are inferred from the claim text.