Corner field effect of the CMP oxide recess in shallow trench isolation technology for high density flash memories

摘要

This paper presents CMP oxide recess with corner field effect in STI technology for high density, sub-0.35 /spl mu/m flash memories. Trench corners with different shape have shown to correlate with CMP recess. We have shown for the first time that non-uniform CMP polish across wafer leads to broad V/sub t/ distribution. Corner field effect at trench edge may play a role. Analytical model based on energy band structure is simulated.