Study of Gate Misalignment Effects in Single-Material Double-Gate (SMDG) MOSFET Considering Source and Drain Lateral Gaussian Doping Profile

Abstract

Un-intentional misalignment in the gate due to fabrication leads to undesirable device performances. In this paper, effect of gate misalignment has been presented in single-material double-gate (SMDG) MOSFET, based on simulation. The source and drain are considered to be doped with lateral Gaussian doping profile. A simulation study is performed to analyze the gate misalignment effects on the performance. A combination of total four misalignment is simulated, the effects on surface potential, device I-V characteristics and transconductance has been studied. We consider the misalignment at drain and source side of both front and back gate. When misalignment is there both trans-conductance and drain current decreases. Misalignment from drain and source side decreases trans-conductance similarly, but for 45% misalignment in the front gate, 34.8% degradation in the drain current is observed while similar misalignment in back gate causes 57.5% degradation. For simulations 2-D simulations by ATLAS™ from Silvaco Inc. is used and surface potential profile is obtained.