Factors affecting the temperature stability of APCVD systems in a rapidly changing semiconductor manufacturing environment

Reports on a comprehensive characterization effort carried out in understanding the effects of air flow and exhaust pressure and velocity on the temperature stability of an APCVD tool used to deposition of contact dielectric layer. Air flow and pressure were measured at different locations within the system and in close proximity to the tool in both the process bay and the service chase to ascertain the flow dynamics. Effects of air flow and exhaust pressure fluctuations and convective heat transfer under various deposition process conditions were studied. In addition, a statistically designed experiment was conducted using an air flow visualization approach to observe the air flow patterns through the APCVD reactor as a function of various exhaust velocities as well as different air blocking schemes to restrict the direction and flow of air from bay to chase. Effects of this phenomena on equipment availability and uptime are discussed. Several solutions including both hardware modifications of the tool and changes to the facilities design and configuration are presented.