A comprehensive study of InGaAs based linearly graded channel DL-TFET and its single event transient effect

Abstract

In this paper, the DC, RF and single-event transient effect studies are carried out for investigating the performance and reliability of hetero-junction InGaAs DL-TFET having linearly graded channel region. The mole-fraction of source side In1−xGaxAs is varied for obtaining the higher ION i.e. obtained at x = 0.40; this also impact the RF simulation studies by increasing the gain-bandwidth product range to 52.4 GHz. To reduce Iambipolar, a step junction is introduced for first time in the channel region at channel-drain interface which reduces the Iambipolar by 93.27% to the magnitude of 0.867 μA μm−1. Further reduction in ambipolarity is achieved at TG = 3.9 eV to the level of 0.269 fA μm−1, ION increases to 0.558 mA μm−1, sub-threshold swing is 23.8 mV/decade and shows highest cut-off frequency upto 155 GHz. Hence, the optimized device structure is investigated under the influence of single-event transient; therefore, the effect of heavy ion is investigated on optimized linearly graded structure for different LETs’ (Linear energy transfer). It shows increase in the drain current and charge collected with increase in LET. The maximum IDS is 0.618 mA μm−1 in OFF state, and IDS of 0.819 mA μm−1 in ON state at VDS = 1.0 V, which is higher than its ION at 10 MeV.cm2/mg (i.e. 0.11 pC μm−1). By simulating heavy ion single event effect on different positions, it is found that channel-drain interface is more sensitive to irradiation. This gives an insight for radiation hardened applications in space for TFET based circuit designs.