Fabrication and characterization of InGaAs fin structure high electron mobility transistors

The InGaAs planar and fin structure high electron mobility transistors (FinHEMTs) are demonstrated in this report. Compared with planar devices, threshold voltage (VT) of FinHEMT increases from -1.64 V to -1.04 V at VD = 2.0 V. On the other hand, sub-threshold swing (SS) decreases from 251.8 mV/decade to 88.4 mV/decade and drain induced barrier lowering (DIBL) reduces from 105.2mV/V to 52.6mV/V. A Silvaco TCAD is used to simulate band diagram of gate region to verify and explain the gate control mechanisms of FinHEMT. The simulation results indicate that band bending at metal and semiconductor interface, which is between etched fin sidewall and gate metal has significantly large influence on device on-off characteristics.