Demonstration of MOSFET-like on-current performance in arsenide/antimonide tunnel FETs with staggered hetero-junctions for 300mV logic applications

Type II arsenide/antimonide compound semiconductor with highly staggered GaAs_0.35Sb_0.65/In_0.7Ga_0.3As hetero-junction is used to demonstrate hetero tunnel FET (TFET) with record high drive currents (I_ON) of 190μA/μm and 100μA/μm at V_DS=0.75V and 0.3V, respectively (L_G=150nm). In_xGa_1-xAs (x=0.53, 0.7) homo-junction TFETs and GaAs_0.5Sb_0.5/In_0.53Ga_0.47As hetero TFET with moderate stagger are also fabricated with the same process flow for benchmarking. Measured and simulated TFET performance is benchmarked with 40nm strained Si MOS-FETs for 300mV logic applications.

Introduction

Inter-band tunnel FETs (TFETs) are promising devices for realizing sub-kT/q steep switching slope (SS). Compared to MOSFET, however, the TFET drive current (I_ON) is considerably low due to the large source side tunneling barrier (E_beff). Bandgap (E_g) engineered III-V hetero-junctions could meet the I_ON requirement while achieving sub-kT/q SS and low off-state leakage current (I_OFF) (1). In this work, we experimentally demonstrate GaAs_0.35Sb_0.65/In_0.7Ga_0.3As highly staggered hetero-junction TFET and show 400% I_ON enhancement over corresponding In_0.7Ga_0.3As homo-junction TFET. Using calibrated numerical simulations, we further show that MOSFET-like high I_ON can be achieved using highly staggered hetero-junction, ultra thin body and low EOT for Vcc=300mV logic applications.