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休斯研究所报导了低噪声0.1μm栅长GaAs MESFET的实验结果。该器件是用MBE技术在半绝缘GaAs衬底上连续生长不掺杂AlGaAs p~-缓冲层和GaAs p~-缓冲层,6×10~(18)cm~(-8)有源层,5×10~(16)cm~(-3)势垒层以及6×10~(18)cm~(-3)接触层。其优点是:器件有效电长度缩短,寄生电容减小,栅极对沟道电荷控制增强,势垒高度提高,栅极漏电降低,而大带隙的AlGaAs层加强了对载流的制约。制得的FET性能为:最大跨导g_m=600mS/mm,输出电导g_o=30mS/mm,电压增益(g_m/g_o)=20,据称,是迄今GaAs MESFET和GaAs/AlGaAs MODFET(0.3μm栅)所报导的最好结果。电流增益截止频率f_T超过65GHz,最高80GH;
Hughes Institute reported the experimental results of a low-noise 0.1μm gate-length GaAs MESFET. In this device, an undoped AlGaAs p ~ - buffer layer and a GaAs p ~ - buffer layer, 6 × 10 ~ (18) cm ~ (-8) active layer are continuously grown on a semi-insulating GaAs substrate using MBE technology. × 10 ~ (16) cm ~ (-3) barrier layer and 6 × 10 ~ (18) cm ~ (-3) contact layer. The advantages of the device are as follows: the effective electrical length of the device is shortened, the parasitic capacitance is reduced, the gate charge control of the channel is enhanced, the barrier height is increased and the gate leakage is reduced, and the large bandgap AlGaAs layer enhances the current-carrying restriction. The resulting FET performance was: maximum transconductance g_m = 600 mS / mm, output conductance g_o = 30 mS / mm, voltage gain (g_m / g_o) = 20, which is said to have been so far GaAs MESFETs and GaAs / AlGaAs MODFETs ) Reported the best result. Current gain cutoff frequency f_T over 65GHz, up to 80GH;