Optimization of LPCVD silicon nitride deposition process by use of designed experiments

A low-pressure chemical-vapor-deposition (LPCVD) nitride process that was characterized for film uniformity and particle density is described. The appropriate factors and levels for an optimization experiment were established. A full factorial experiment and a Taguchi orthogonal array were selected. A confirmation run was processed to verify the optimum factor level settings from two design methodologies. SPC methods, (as measured by C_p) were used to measure an overall process improvement for film uniformity. Particle trends for the implemented process are compared to particle trends on a previously used process