Engineering Improvement of the Core Layers of Charge Trapping Flash Memory Based on Doped HfO2 and Segmented Fabrication

Abstract

An engineering approach was applied to modify the core layers of charge-trapping flash (CTF) memory—the blocking layer, charge-trapping layer, and tunneling layer. The doping of Ti in the charge-trapping layer and the use of Si-doped HfO2 for the tunneling layer could optimize charge capture and leakage control. This design enhances programming and erasing speeds and increases overall device stability by creating more corner fields and using the Coulomb blockade effect. Experimental results demonstrate a larger memory window and better charge retention for the new device at the same charge-trapping layer thickness. These findings signify the advancement of the new CTF memory in balancing fast programming and long-term charge retention. The long-standing contradiction between charge capturing and retention could be partially resolved by using this engineering method.