Rapid interface parameterization using a single MOS conductance curve
Abstract
Figures are presented for finding interface trap density D_{it} capture probability c_{p}, and interfacial broadening σ_{s}, from a single curve of smallsignal MOS interface trap conductance G_{it}/ ω vs either band bending ν_{s}, or frequency f[ ω = 2 πf]. Almost no computation is necessary. An additional figure allows the depletion layer capacitance to be determined if the oxide capacitance and the measured capacitance at the maximum value of G_{it}/ ω are known. The extension to G_{it}/ ω vs ν_{s}, curves is a convenience. Parameters throughout the bandgap can be obtained from measurements at fewer frequencies than are needed for construction of accurate G_{it}/ ω vs f curves. Economy also results because data usually are obtained by sweeping gate bias at selected frequencies. Construction of G_{it}/ ω vs ν_{s} curves from the data is simpler than G_{it}/ ω vs f, particularly if ν_{s} is measured directly. The information needed from the G_{it}/ ω curve is the maximum value of G_{it}/ ω and the width of the peak at an arbitrary fraction of its maximum value, fw. In addition, for capture probability only, the frequency and band bending at the peak maximum are needed, as well as the bulk doping. The method assumes validity of the Gaussian approximation to broadening of the conductance peak. Comparison of the parameters obtained for several choices of fw allows a check of this assumption, which usually is valid for MOS devices.
 Publication:

Solid State Electronics
 Pub Date:
 August 1983
 DOI:
 10.1016/00381101(83)900308
 Bibcode:
 1983SSEle..26..711B