Radiation-Induced Interface States of Poly-Si Gate MOS Capacitors Using Low Temperature Gate Oxidation

The effect of gate oxidation temperature on radiation-induced flatband and threshold voltage shifts and interface state buildup for steady-state Co60 irradiation have been studied for poly-Si gate MOS capacitors with pyrogenic and dry gate oxides. The smallest radiation-induced flatband and threshold voltage shifts can be achieved with a pyrogenic oxide grown at 850°C. Total dose effects, applied gate bias during the irradiation and oxide thickness dependence were also evaluated for low temperature pyrogenic oxide MOS capacitors. We obtained a 2/3 power law dependence of radiation-induced interface states on the total dose and the oxide thickness.

[1]  MOS Hardness Characterization and Its Dependence upon Some Process and Measurement Variables , 1976, IEEE Transactions on Nuclear Science.

[2]  F. B. McLean.  A Framework for Understanding Radiation-Induced Interface States in SiO2 MOS Structures , 1980, IEEE Transactions on Nuclear Science.

[3]  C. Sah,et al.  Origin of Interface States and Oxide Charges Generated by Ionizing Radiation , 1976, IEEE Transactions on Nuclear Science.

[4]  P. S. Winokur,et al.  Field- and Time-Dependent Radiation Effects at the SiO2/Si Interface of Hardened MOS Capacitors , 1977, IEEE Transactions on Nuclear Science.

[5]  P. S. Winokur,et al.  Dependence of Interface-State Buildup on Hole Generation and Transport in Irradiated MOS Capacitors , 1976, IEEE Transactions on Nuclear Science.

[6]  P. S. Winokur,et al.  Interface-State Generation in Radiation-Hard Oxides , 1980, IEEE Transactions on Nuclear Science.

[7]  M. H. Woods,et al.  Hole traps in silicon dioxide , 1976 .

[8]  P. S. Winokur,et al.  Two‐stage process for buildup of radiation‐induced interface states , 1979 .

[9]  J. M. Aitken,et al.  Location of positive charges in SiO2 films on Si generated by vuv photons, x rays, and high‐field stressing , 1977 .

[10]  B. L. Gregory,et al.  Process technology for radiation-hardened CMOS integrated circuits , 1976 .

[11]  C. N. Berglund.  Surface states at steam-grown silicon-silicon dioxide interfaces , 1966 .

[12]  K. Schlesier,et al.  Processing Effects on Steam Oxide Hardness , 1976, IEEE Transactions on Nuclear Science.

[13]  Walter C. Johnson,et al.  Relationship between trapped holes and interface states in MOS capacitors , 1980 .

[14]  Andrew Holmes-Siedle,et al.  A Simple Model for Predicting Radiation Effects in MOS Devices , 1978, IEEE Transactions on Nuclear Science.