Compensation of Hot Carrier Degradation Enabled by Forward Back Bias in π-GAA-π MOSFET

Abstract

Forward back biasing (FBB) technique is considered as a potential solution for aging compensation in silicon on insulator (SOI) MOSFET. However, traditional SOI devices under FBB would suffer from extra off-state leakage current <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(I_{\mathrm{ off}})$ </tex-math></inline-formula> and undesirable static power consumption. In this work, we studied the hot carrier degradation and FBB compensation in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> -GAA- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> MOSFET. With the unique hybrid gate structure, the performance degradation is found to be less severe than pure <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> gate device; and moreover it can be partially recovered by FBB without the sacrifice of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\mathrm{ off}}$ </tex-math></inline-formula> . The presence of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> gates offer the back gate tunability that is not provided by pure GAA gate; while the GAA gate component can effectively prevent the impact of FBB from affecting the surface potential. Our findings in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> -GAA- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula> hybrid gate MOSFETs would be beneficial for device reliability improvement.