Development of SiNx LPCVD processes for microtechnological applications

Various silicon rich silicon nitride SiNx films have been deposited by low- pressure chemical vapour deposition (LPCVD) from dichlorosilane SiH2Cl2 and ammonia NH3. Deposition rate, refractive index, residual stress and SiNx s toichiometry are studied as a function of deposition parameters, evidencing the main influence of the NH3/SiH2Cl2 gas ratio. However, as such SiNx lay ers have special applications for micro-opto-electromechanical systems (MOE MS), the influences of the deposition conditions are more precisely studied for improving the uniformity properties along the load. In order to achiev e this goal, different load configurations are tested and the use of non-is othermal furnace profiles is proposed in order to develop the LPCVD deposit ion technique of SiNx films for industrial microtechnological processes.