Book excerpt: In this paper, we will investigate a metal- insulator-semiconductor (MIS) like InGaAs/GaAs doped-channel structure both in theoretical analysis and experiment. First, a charge control model is employed to simulate the basic electronic properties of the doped-channel field-effect transistor (FET). Then, a practical device is fabricated and processed. From the results, we can find that the device shows good transistor characteristics. 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 swing larger than 3V with the transconductance higher than 200mS/mm are obtained for a 2x100 um2 gate-dimension FET. From the comparison, we find that the experiments are in good agreement with the theoretical simulations. The, performances provide a promise of the proposed device to be a good candidate for practical circuit applications.