砷化鎵金半場效電晶體電路旁閘效應之數值研究

Abstract

以數值模擬分析研究砷化鎵金半場效電晶體電路之旁閘效應，首度成功的 針對實際的旁閘結構，以二維數值分析釐清此效應之機制，並對其材料、 幾何佈局、溫度、照光條件等相關因素，和幾種抑制此效應的方法一一深 入探討。所有的模擬結果與實驗所觀察到的現象都相當吻合，一個可以完 整解釋旁閘效應所有表徵的模型從而得以建立。 Two-dimensional numerical analyses (both transient and steady state) of the sidegating effect in GaAs MESFET's have been performed for the first time with a realistic configuration. The results show that hole injection and the presence of hole traps in the substrate are essential to the sidegating effect. The commonly observed features of the effect, including the hysteresis, temperature dependence, light-sensitivity, and geometrical position dependence are investigated. Shielding of the effect with a biased Schottky bar and suppression of the effect with ion bombardment are studied. The effect of sidegating on circuit operation is also clarified. All these results show good agreement with the experimental findings and a model which can consistently account for all these observed features of sidegating has been thus established.