Simultaneous quality improvement of tunneling- and interpoly-oxides of nonvolatile memory devices by NH/sub 3/ and N/sub 2/O nitridation

This brief presents a new nitridation process on a floating poly-Si gate to improve the quality of both tunneling oxide and interpoly-oxide of nonvolatile memories. Three types of poly-Si for a floating gate have been investigated. We found in-situ doped poly-Si shows the best performance in terms of breakdown field, charge-to-breakdown (Q/sub BD/) and trapping rate. The Q/sub BD/ of interpoly-oxide can be reached as high as 35 C/cm/sup 2/. This scheme is very promising for nonvolatile memory devices.