Enhanced Programming and Erasing Speeds in P-Channel Charge-Trapping Flash Memory Device With SiGe Buried Channel

The operation characteristics of p-channel TaN/ Al
₂
O
₃
/HfO
₂
/HfAlO
₂
/SiO
₂
/Si MAHOS-type nonvolatile memory devices with different Ge contents in a SiGe buried channel are investigated in this letter. Compared with those of a device having a conventional Si-channel, both programming and erasing speeds are significantly improved by employing a Si
_0.7
Ge
_0.3
buried channel. Satisfactory retention and excellent endurance characteristics up to 10
⁶
P/E cycles with 4.1-V memory window show that the degradation on reliability properties, if it exists, is negligible when the SiGe buried channel is introduced.