Comparison of interface-state buildup in MOS capacitors subjected to penetrating and nonpenetrating radiation

Metal‐SiO2‐Si capacitors under positive bias were subjected to penetrating Co60 γ and nonpenetrating 10.2‐eV uv radiation. High‐frequency 1‐MHz and quasistatic C‐V curves were recorded before and after irradiation, and interface‐state densities over the Si band gap were calculated from these curves by using the Terman, Berglund, and Castagne techniques. The nature and magnitude of the buildup of interface states were similar for both types of irradiation, demonstrating that the buildup is not related to the direct interaction of radiation at the interface or a structural modification of the SiO2 layer, but to the production of electron‐hole pairs in the oxide and the subsequent transport of holes to the oxide‐semiconductor interface. The buildup of interface states under irradiation saturated at ∼5×105 rad (SiO2).

[1]  J. R. Srour,et al.  Hole and electron transport in SiO2 films , 1974 .

[2]  J. R. Brews,et al.  Surface Potential Fluctuations Generated by Interface Charge Inhomogeneities in MOS Devices , 1972 .

[3]  M. Pepper.  Low energy electron irradiation of the Si-SiO2 interface , 1972 .

[4]  R. Castagné,et al.  Description of the SiO2Si interface properties by means of very low frequency MOS capacitance measurements , 1971 .

[5]  R. C. Hughes.  Hole mobility and transport in thin SiO2 films , 1975 .

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

[7]  G. F. Derbenwick,et al.  Vacuum Ultraviolet Radiation Effects in SiO2 , 1971 .

[8]  L. Terman.  An investigation of surface states at a silicon/silicon oxide interface employing metal-oxide-silicon diodes , 1962 .

[9]  M. Kuhn,et al.  A quasi-static technique for MOS C-V and surface state measurements , 1970 .

[10]  F. B. McLean,et al.  Role Transport and Charge Relaxation in Irradiated SiO2 MOS Capacitors , 1975, IEEE Transactions on Nuclear Science.

[11]  H. Hughes.  Radiation-Induced Perturbations of the Electrical Properties of the Silicon-Silicon Dioxide Interface , 1969 .

[12]  E. H. Nicollian,et al.  The si-sio, interface – electrical properties as determined by the metal-insulator-silicon conductance technique , 1967 .

[13]  F. B. McLean,et al.  Electron-hole pair-creation energy in SiO2 , 1975 .

[14]  H. R. Philipp,et al.  Optical transitions in crystalline and fused quartz , 1966 .

[15]  Tso-Ping Ma,et al.  Comparison of interface-state generation by 25-keV electron beam irradiation in p-type and n-type MOS capacitors , 1975 .