We demonstrate high-performance In_(0.23) Ga_(0.77) As channel metal-oxide-semiconductor Seld-effect transistors(MOSFETs) with high on-current to off-current(I_(0n)/I_(0ff)) ratio grown on semi-insulating GaAs wafers by metal-organic chemical vapor deposition(MOCVD).The 2μm channel-length devices exhibit a peak extrinsic transconductance of 150mS/mm and a drain current up to 500mA/mm.The maximum effective mobility is 1680cm~2/Vs extracted by the split C-V method.Furthermore,the I_(on)/I_(off) ratio is significantly improved from approximately 4.5×10~3up to approximately 4.32×10~4 by controlling the etch thickness of In_(0.49)Ga_(0.51)P.The high drain current and high I_(on)/I_(off) ratio of the In_(0.23) Ga_(0.77) As channel MOSFETs are achieved due to the high effective mobility and the low gate leakage current density. We demonstrate high-performance In_ (0.23) Ga_ (0.77) As channel metal-oxide-semiconductor Seld-effect transistors (MOSFETs) with high on-current to off- current (I_ (0n) / I_ (0ff)) ratio grown on semi-insulating GaAs wafers by metal-organic chemical vapor deposition (MOCVD). The 2 μm channel-length devices exhibit a peak extrinsic transconductance of 150 mS / mm and a drain current up to 500 mA / Vs extracted by the split CV method. Morerther, the I / (off) ratio is significantly improved from about 4.5x10 ~ 3up to about 4.32x10 ~ 4 by controlling the etch thickness of In_ (0.49) Ga_ ( 0.51) P.The high drain current and high I / (off) ratio of the In_ (0.23) Ga_ (0.77) As channel MOSFETs are achieved due to the high effective mobility and the low gate leakage current density.