Metamorphic In/sub 0.53/Ga/sub 0.47/As-In/sub 0.52/Al/sub 0.48/As tunnel diodes grown on GaAs

We demonstrate, for the first time, functional metamorphic In/sub 0.53/Ga/sub 0.47/As/In/sub 0.52/Al/sub 0.48/As tunnel diodes on GaAs(100). Two types of tunnel diodes are presented. Type-A tunnel diodes show a peak current density of 50,000 A/cm/sup 2/, a peak to valley current ratio of 10 and a f/sub max/ of 2.5 GHz. Type-B tunnel diode shows a peak current density of 9,000 A/cm/sup 2/, and PVCR of 25. AFM images of the as grown tunnel diodes show a surface RMS roughness of approximately 35 /spl Aring/. TEM micrographs and X-ray diffraction of In/sub 0.53/Ga/sub 0.47/As/In/sub 0.52/Al/sub 0.48/As metamorphic test structures indicate smooth abrupt interfaces that are comparable to lattice matched structures.