Characteristics of metal-insulated-semiconductor (MIS) like In0.2Ga0.8As/GaAs doped-channel structure

A metal-insulated-semiconductor (MIS) like In0.2Ga0.8As/GaAs doped-channel structure has been proposed. Furthermore, a field-effect transistor (FET) based on the proposed structure is also Fabricated. Both theoretical simulations and experiments are made and compared in this paper. First, the theoretical analysis by using the self-consistent method with a quadratic expression of the charge control process is employed to simulate the basic electronic properties of the doped-channel FET. From the simulation results, we can find that the d.c. performances show good transistor characteristics. For the experimental results, a high breakdown voltage of 17.4 V, a maximum drain saturation current of 930 mA/mm, a maximum transconductance of 235 mS/mm, and a very broad gate voltage range larger than 3 V with the transconductance higher than 200 mS/mm are obtained for a 2 x 100 mu m(2) gate-dimension FET. From the comparison, we find that experiment results are in a good agreement with the theoretical simulations. The performances provide a promise of the proposed device to be a good candidate for practical circuit applications.