A new Al-free HFET structure: The pseudomorphic p-InP/n-InP/In/sub 0.75/GaAs double heterostructure /spl delta/-doped HEMT

Abstract

A new type of low pressure metal organic vapor epitaxial grown high electron mobility transistor (HEMT) device is reported. By using only a strained In/sub 0.75/Ga/sub 0.25/As quantum well (QW)-channel and InP as a carrier supplying n-type, /spl delta/-doped and barrier-enhancement p-type layers, a high performance pseudomorphic double heterostructure (DH)-HEMT has been created. The authors present the growth, device fabrication, material quality, and the DC- and RF-performance of 0.8 /spl mu/m-devices, which show extremely good characteristics. The approach described here may serve as an useful alternative to InAlAs containing structures because it eliminates many troublesome effects such as kinks, deep levels, interface states, high output conductances and gate leakages, which are attributed to a large extent to impurity-Al interactions.<>