臺灣博碩士論文加值系統

在直流儲存/擦拭中,直接加上一個負電壓於源/基極,於是把一寄生於電子
可擦拭可儲存唯讀記憶體之電子可儲存唯讀記憶體導通.通道式熱電子產
生並加入F-N穿透式電流, 一起參與儲存動作.在高頻波動式儲存/擦拭方
式,直接在元件之閘極加上正(負)高頻高壓之波群,於是元件儲存(擦拭)後
之電位均顯著地加強.這是由於高頻波動,窄波引起深層空乏狀態下而激發
另一額外的熱電子所導致.經由實驗證明此種儲存/擦拭方式確實比傳統之
儲存/ 擦拭使用較小之電壓. 於是本論文之研究成果可以應用在未來的電
子可擦拭可儲存唯讀記憶體.

In this thesis, Two writing/erasing methods using dc voltage or
high-frequencypulses for FLOTOX EEOROM cells are presented and
analyzed. They have also beensuccessfully verified by
experimental devices.In the DC writing/erasing, an extra dc
negative source and substrate voltageis added to turn on the
parasiticEPROM device in the FLOTOX EEPROM. Thus thechannel hot-
electron injection current in addition to the F-N
tunnelingcurrent can be generated in writing the FLOTOX EEPROM
devices. Thus thewriting efficiency can be increased.In the
high-frequency pulse writing and erasing in the FLOTOX EEPROM
devices,a positive (negative) voltage pulse train is applied to
the gate.Thewriting (erasing) operation becomes much more
efficient so that the written(erased) efficiency is enhanced by
the extra hot-carrier injection under thedeep depletion
condition (DDC) which is caused by high-frequency gate pulses,
short pulse base-level duration, and leaky oxide. It has been
verified fromthe measurement data that the pulse writing and
erasing operations can beperformed with a lower voltage than
the conventional dc operations. Thus theycan be applied in
future EEPROM.