Influence of the Poly Gate Depletion Effect on Programming EEPROM Cells
To ensure a data retention time of e.g. 10 years a maximum allowed floating gate doping concentration can not be exceeded. The data retention time can be improved by reducing the floating gate doping concentration. This reduction causes a so far negligible depletion effect in the floating gate reducing the V T -shift by approximately 1.5 Volts at a floating gate doping of 3.1019 cm-3. A trade-off will be discussed.
KeywordsDoping Concentration Voltage Drop Poly Silicon Depletion Region Tunnel Current
Unable to display preview. Download preview PDF.
- H. Watanabe et al., Scaling of Tunnel Oxide Thickness for Flash EEPROMs Realizing Stress-Induced Leakage Current Reduction, Symposium on VLSI Technology Digest of Technical Papers, p. 47. 1994Google Scholar
- N. D. Arora, R. Rios and C.-L. Huang, Modeling the Poly silicon Depletion Effect and Its Impact on Submicrometer CMOS Circuit Performance. Transactions on Electron Devices, vol. 42, No. 5, May 1995Google Scholar
- Luey Chwan Liong and Po-ching Liu, A Theoretical Model for the Current-Voltage Characteristics of a Floating-Gate EEPROM Cell, Transactions on Electron Devices, vol. 40, no. 1, January 1993 Google Scholar