GaAs-InGaAs-GaAs Fin-Array Tunnel Diodes on (001) Si Substrates With Room-Temperature Peak-to-Valley Current Ratio of 5.4

In this letter, we report the selective area growth of GaAs, In
_0.2
Ga
_0.8
As, and GaAs/In
_0.2
Ga
_0.8
As/GaAs quantum-well fins of 65-nm width on exactly orientated (001) Si substrates. By exploiting high aspect ratio trenches formed by patterned SiO
₂
on Si and a V-grooved Si (111) surface in the aspect ratio trapping process, we are able to achieve good material quality and structural properties, as evidenced by x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The fabricated GaAs-In
_0.2
Ga
_0.8
As-GaAs fin-array tunnel diodes exhibit a maximum room-temperature peak-to-valley current ratio of 5.4, and negative differential resistance characteristics up to 200 °C.