应用于毫米波的三五族半导体元件.pdf

1 02 III-V Semiconductor Devices for Millimeter- wave Applications 1,2 1 1 1 2 GaAs PHEMT (Pseudomorphic High Electron Mobility Transistor) GaAs MHEMT (Metaphorphic-HEMT) InP HEMT MHEMTs (Buffer Layer) Misfit Dislocation( ) Active Layer PHEMTs (Buffer Layer) Misfit Dislocation InP In0.53Ga0.47As In0.52Al0.48As Misfit Dislocation (Gate Sinking) (Cgs) InGaAs Abstract In this paper, We report some of our previous work about III-V semiconductor devices for millimeter wave applications, including GaAs PHEMT (Pseudomorphic High Electron Mobility Transistor), GaAs MHEMT (Metaphorphic-HEMT), and InP HEMT. For MHEMTs, due to the lattice mismatch between each layer, a thick buer layer is required to prevent mist dislocations from extending into active layers. However, for PHEMTs, the lattice constant of each layer is very close, therefore, no thick buer layer is required to reduce the mist dislocations during epitaxy. For InP HEMT, the lattice constant of InP matches that of In0.53Ga0.47As and In 0.52Al0.48As, hence, a very good crystalline quality could be obtained. The gate sinking process can be applied to reduce the resistance and capacitance Cgs between source and gate, and the RF