Abstract
When floaging gate device can't satisfy smaller device, SONOS-Type is the one of candidate to replace it. SONOS-Type device tunneling layer thickness is about 30A,it is a problem for retention. How to improve our device performance is very important. In our experiment, using various high-k dielectrics as stacked SONOS-Type blocking layer. Different materials has different performances, matching stacked structure by nitrogen treatment with distinct doses(2mins, 4mins, 8mins), bandgap-engineering, k-value as a excellent blocking oxide layer. For tunneling oxide, the application of multilayer dielectric stacks is promising to realize tunnel barrier engineering. With a suitable combination of stacked tunneling oxide(low-k/high-k),a lower operation voltage can be achieve. Using Al2O3/HfAlO as blocking layer has better performance than other stacked structures. Take high bandgap material as first layer blocking layer,and secondly stack higher k material can improve device performance. Stacking a high quality film as blocking layer first and then stack various high-k materials by PIII nitrogen treatment can reduce crystallize and enhance retention, promote device reliability after high temperature annealing process.