The C-V characteristics of Schottky barriers on laboratory grown semiconducting diamonds

Abstract Measurements of the differential capacitance of evaporated gold Schottky barriers on laboratory-grown, boron-doped semiconducting diamonds have been obtained for the first time as functions of reverse-bias voltage, frequency, and temperature. The data are analyzed on the basis of a model which includes the effects of long time constants for hole capture from the deep (boron) level, as well as previously unobserved effects due to the series resistance of the bulk. The barrier height at 300°K is found to be 1·73 ± 1·10 eV , in good agreement with the ‘one-third band gap’ value of Mead and Spitzer. Excellent correlation is found between optical transmission measurements and the C-V analysis for the uncompensated boron concentration, indicating that all of the optically observable dopant is electrically active. By fitting the model with two adjustable parameters at room temperature, good agreement is obtained between measured and calculated capacitance over two and a half decades as a function of temperature. The analysis indicates that the activation energy of the acceptor level is 0·26–0·37 eV for the samples studied, while the associated capture cross-sections are 0·9–2·0 × 10 −17 cm 2 .

[1]  A. G. Milnes,et al.  Effects of deep impurities on n + p junction reverse-biased small-signal capacitance , 1968 .

[2]  D. Losee.  Admittance spectroscopy of deep impurity levels: ZnTe Schottky barriers , 1972 .

[3]  V. Prosser.  Sensitive method of measuring small changes in light intensities its use in measurements of high effective masses in semi-conductors from faraday rotation , 1965 .

[4]  K. Hesse,et al.  On the frequency dependence of GaAs Schottky barrier capacitances , 1972 .

[5]  Y. Zohta.  Frequency Response of Gold Impurity Centers in the Depletion Layer of Reverse‐Biased Silicon p+n Junctions , 1972 .

[6]  C. Sah,et al.  Frequency dependence of the reverse-biased capacitance of gold-doped silicon P + N step junctions , 1964 .

[7]  C. R. Crowell,et al.  Erratum: Capacitance energy level spectroscopy of deep‐lying semiconductor impurities using Schottky barriers , 1970 .

[8]  A. T. Collins,et al.  Electrical-Transport Measurements on Synthetic Semiconducting Diamond , 1966 .

[9]  Carver A. Mead,et al.  Fermi Level Position at Metal-Semiconductor Interfaces , 1964 .

[10]  E. P. Eernisse.  Accurate Capacitance Calculations for PN Junctions Containing Traps , 1971 .

[11]  Nevill Mott,et al.  The theory of impurity conduction , 1961 .

[12]  J. Basinski,et al.  Capacitance of Junctions on Gold‐Doped Silicon , 1968 .

[13]  A. T. Collins,et al.  The nature of the acceptor centre in semiconducting diamond , 1971 .

[14]  P. V. Gray,et al.  Si ‐ SiO2 Fast Interface State Measurements , 1968 .

[15]  Hall Coefficient and Magnetoresistance in Semiconducting Diamond , 1959 .

[16]  C. R. Crowell,et al.  Deep level impurity effects on the frequency dependence of Schottky barrier capacitance , 1972 .