Study of GaInP/InGaAs Linear Graded Schottky Barrier Double Channel Heterostructure Field-effect Transistors(GDCHFETs)

摘要

Fabrications of GaInP/InGaAs linear-grade Schottky barrier double channel heterostructure field effect transistors (GDCFETs) are presented. The DC and RF characteristics of the studied devices with 1 and 0.8μm gate length are compared and studied. By using the linear-grade Schottky barrier layer, the drawback of parallel conduction at high stress operation (especially at high gate voltage or high operation temperature) is eliminated. In addition, due to the employed InGaAs structure and Schottky behaviors of InGaP "insulator", good pinch-off and saturation characteristics, higher and linear transconductance, and good RF performances are obtained. The maximum transconductance is 218mS/mm and 221 mS/mm for 1μm and 0.8um gate length, respectively. The output current, defined at VGS = 1.2V is 380mA/mm and 434mA/mm for 1 and 0.8um gate length, respectively. High-speed device operation has been verified, with fT of 15GHz and fmax of 31 GHz for 1 and 0.8μm gate length at room temperature. Therefore, the studied GDCHFETs provide the promise for high-temperature and high-performance microwave electronic applications.