Study of the electronic trap distribution at the SiO/sub 2/-Si interface utilizing the low-frequency noise measurement

A correlation of the trap distribution at the silicon-oxide interface with the low-frequency noise measurement in MOS devices at temperatures ranging from 77 to 300 K is presented. Several devices with differently prepared gate oxides were used to study the process-induced trap distribution. Several peaks varying from sample to sample are found in a frequency index of noise spectrum versus temperature plot and are correlated with the discrete trap distribution across the bandgap of silicon. This method provides more information on traps as it circumvents the complexity of superimposing different traps which was encountered in the capacitance-voltage (C-V) method. Results, either compatible with others' work or consistent with data based on other measurements, show that the electronic trapping behavior in MOS structures is governed by two intrinsic traps located at 0.12 and 0.3 eV (both measured from the conduction band) for all kinds of oxides. In addition, dry oxidation was found to introduce an additional trap at an energy level of 0.23 eV, and annealing the gate oxide in ammonia at a high temperature (>1000 degrees C) results in an enhancement of the trap density of 0.43 eV below the conduction band edge of silicon, which was also observed in a quasi-static C-V measurement. >

[1]  F. M. Klaassen,et al.  Characterization of low 1/f noise in MOS transistors , 1971 .

[2]  M. Schulz.  Interface states at the SiO2-Si interface , 1983 .

[3]  Piero Olivo,et al.  Low‐frequency noise in silicon‐gate metal‐oxide‐silicon capacitors before oxide breakdown , 1987 .

[4]  A. Madhukar,et al.  A kinetic model for the thermal nitridation of SiO2/Si , 1986 .

[5]  K. S. Chari,et al.  Dependence of Si-SiO2 interface state density on oxide thickness in structures with ultrathin (79-227 Å) oxides , 1985 .

[6]  P. M. Horn,et al.  Low-frequency fluctuations in solids: 1/f noise , 1981 .

[7]  Dieter K. Schroder,et al.  Low frequency noise and DLTS as semiconductor device characterization tools , 1988 .

[8]  R. Howard,et al.  Discrete Resistance Switching in Submicrometer Silicon Inversion Layers: Individual Interface Traps and Low-Frequency ( 1 f ?) Noise , 1984 .

[9]  Ingemar Lundström,et al.  Low frequency noise in MOS transistors—II Experiments , 1968 .

[10]  K. K. Hung,et al.  Characterization of metal‐oxide‐semiconductor transistors with very thin gate oxide , 1986 .

[11]  E. Arnold,et al.  Surface states and 1/f noise in MOS transistors , 1967 .

[12]  H. Fu,et al.  Theory and experiments on surface 1/f noise , 1972 .

[13]  Bruce E. Deal,et al.  Dependence of Interface State Density on Silicon Thermal Oxidation Process Variables , 1979 .

[14]  Donald R. Young,et al.  Reduction of electron trapping in silicon dioxide by high‐temperature nitrogen anneal , 1981 .

[15]  H. Esaki,et al.  Interface states and fixed charges in nanometer-range thin nitrided oxides prepared by rapid thermal annealing , 1986, IEEE Electron Device Letters.

[16]  A. van der Ziel,et al.  Flicker Noise in Electronic Devices , 1979 .

[17]  H. Esaki,et al.  Electrical and physical characteristics of thin nitrided oxides prepared by rapid thermal nitridation , 1987, IEEE Transactions on Electron Devices.

[18]  D. R. Young,et al.  High temperature annealing behavior of electron traps in thermal SiO2 , 1984 .

[19]  J. Shappir,et al.  Modeling of charge‐injection effects in metal‐oxide‐semiconductor structures , 1988 .

[20]  M. Schulz,et al.  TRANSIENT CAPACITANCE MEASUREMENTS OF ELECTRONIC STATES AT THE SiO2-Si INTERFACE , 1978 .

[21]  Anupam Madhukar,et al.  Strain‐dependent defect formation kinetics and a correlation between flatband voltage and nitrogen distribution in thermally nitrided SiOxNy/Si structures , 1985 .

[22]  N. Johnson,et al.  Interface traps and Pb centers in oxidized (100) silicon wafers , 1986 .

[23]  Charles G. Sodini,et al.  Optimization of low-pressure nitridation/reoxidation of SiO/sub 2/ for scaled MOS devices , 1988 .

[24]  Ping-Keung Ko,et al.  Effect of oxide field on hot‐carrier‐induced degradation of metal‐oxide‐semiconductor field‐effect transistors , 1987 .

[25]  K. K. Hung,et al.  Process Dependence of the Si ‐ SiO2 Interface Trap Density for Thin Oxides , 1987 .

[26]  HYDROGEN IN SiO2 FILMS ON SILICON , 1978 .

[27]  Charles Surya,et al.  A thermal activation model for 1/ƒy noise in Si-MOSFETs , 1988 .

[28]  Chenming Hu,et al.  Hot-electron-induced MOSFET degradation—Model, monitor, and improvement , 1985, IEEE Transactions on Electron Devices.

[29]  Y. C. Cheng,et al.  Nitridation‐enhanced conductivity behavior and current transport mechanism in thin thermally nitrided SiO2 , 1988 .

[30]  A. van der Ziel,et al.  Unified presentation of 1/f noise in electron devices: fundamental 1/f noise sources , 1988, Proc. IEEE.

[31]  Mark E. Welland,et al.  Spatial location of electron trapping defects on silicon by scanning tunneling microscopy , 1986 .

[32]  Hsiang,et al.  Theory and experiment on the 1/f gamma noise in p-channel metal-oxide-semiconductor field-effect transistors at low drain bias. , 1986, Physical review. B, Condensed matter.

[33]  P. Balk,et al.  DEFECT STRUCTURE AND GENERATION OF INTERFACE STATES IN MOS STRUCTURES , 1986 .

[34]  Tak H. Ning,et al.  Thermal reemission of trapped electrons in SiO2 , 1978 .

[35]  Y. C. Cheng,et al.  Characterization of Si‐SiO2 interface traps in p‐metal‐oxide‐semiconductor structures with thin oxides by conductance technique , 1987 .