Study on the Stress of Silicon Nitride Film Deposited by PECVD

Silicon nitride film made by the method of plasma enhanced chemical vapor deposition（PECVD） is widely used in the Micro-Electromechanical System（MEMS） because of its such excellent properties as lower deposition temperature,good uniformity and quick deposition rates etc.It is important to investigate the effect of processing parameter on the residual stress of silicon nitride film in order to fabricate stress-free or stress-compensated beam or membrane.Silicon nitride films of high compressive stress、low compressive stress、stress-free、low tensile stress and high tensile stress were deposited in a double-chamber PECVD equipment.The effects of ratio flow of SiH₄/NH₃ and radio-frequency power on the stress of SiNx film were discussed to assist future MEMS development.