Experimental and Theoretical Analysis of the above Threshold Characteristics of Amorphous Silicon Alloy Field Effect Transistors

Abstract

AbstractExperimental studies on the above threshold characteristics of amorphous silicon alloy thin films transistors show that the field-effect mobility has a weak temperature dependence and that the current-voltage characteristics are described by a power law dependence on gate voltage, with an exponent greater than two. These results are in good agreement with our theoretical model, which demonstrates that in the above threshold regime, the Fermi level at the semiconductor-insulator interface lies in the tail states which control device performance. Analysis of the above threshold characteristics shows the characteristic energy variation of the exponential tail state distribution to be ∼22meV and that the on current changes by a factor of only two over the temperature range lO−90°C.