Influence of adsorption kinetics on stress evolution in magnetron-sputtered SiO{sub 2} and SiN{sub x} films

An in situ multi-beam optical sensor system was used to monitor and analyze the force per unit width (F/w) and stress evolution during several stages in magnetron-sputtered SiO{sub 2} and SiN{sub x} films. Stress was observed to relieve quickly after interrupt and recover rapidly after growth resumption in both films. Stress relief was reversible in SiO{sub 2} film but partial reversible in SiN{sub x} film. Stress relief results from both physical and chemical adsorption. Stress recovery is caused by physical desorption. And chemical adsorption results in an irreversible stress relief component. No chemical adsorption occurs in SiO{sub 2} film because of the stable chemical structure. The relationship between adsorption kinetics and films' mechanical behavior is revealed.