Growth of InGaAs-channel transistor layers on large-scale Si wafers for HeteroIntegration with Si CMOS

Abstract

We report on the growth of In 0.30 Ga 0.70 As channel high-electron mobility transistor (HEMT) epi-layers on a 200 mm silicon wafer by metal organic chemical vapor deposition (MOCVD). The device epi-layers were grown on a silicon substrate by using a ∼ 3 μm thick buffer comprising a Ge layer, a GaAs layer and an InAlAs compositionally graded, strain relaxation layer. The achieved epitaxy has a threading dislocation density of (1 - 2) × 10[superscript 7] cm[superscript -2] and a root mean square surface roughness of 6-7 nm. The device active layers include a delta-doped InAlAs bottom barrier, a 15 nm thick InGaAs channel, a 15 nm InGaP top barrier layer and a heavily doped InGaAs contact layer. Long channel MOS-HEMT devices (LG ∼ 20 μm), were fabricated achieving a peak effective electron mobility of ∼ 3700 cm[superscript 2]/V·s.