Applications And Improvement Of DCVD HDP Process In Semiconductor Manufacture

DCVD HDP process is wide used in semiconductor manufacture, this process which induced the two defects:shallow trench isolation(STI) layer void defect and inter metal dielectric(IMD) layer plasma damage. In this research, these defects mechanism were found and improved by change recipe setting and process flow.During the shrinkage of design, HDP had been widely used in CVD STI process. Void defect was found. This research analysis the mechanism of the issue, find the root cause of STI void is Deposition-Etch ratio, optimize and adjust the process parameter (such as RF, gas flow), finally solved this issue.Metal plasma damage was observed by in-line visual inspection after HDP oxide deposition. The defect was easily to be detected on metal lin side-wall which located on isolated or open area. The study results showed that the metal plasma damage defect had a strong correlation with hermal effect of deposition process. Stronger thermal effect on wafer would cause more serious metal void problem. The improvement strategy was to reduce the thermal effect during oxide deposition process. Multi-steps oxide deposition recipe and Silicon Rich Oxide were developed to solve the metal void problem. This research illuminated a clear study way for avoiding void defect and plasma defect. It is a successful experience for HDP process application in semiconductor manufacture.