Understanding Frequency Dependence of Trap Generation Under AC Negative Bias Temperature Instability Stress in Si p-FinFETs
Longda Zhou, Qingzhu Zhang, Hong Yang, Zhigang Ji, Zhaohao Zhang, Qianqian Liu, Hao Xu, Bo Tang, Eddy Simoen, Xueli Ma, Xiaolei Wang, Yongliang Li, Huaxiang Yin, Jun Luo, Chao Zhao, Wenwu Wang
Abstract
In this letter, we present an experimental study on the frequency ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> ) dependence of trap generation under AC negative bias temperature instability (NBTI) stress in Si p-channel fin field-effect transistors (p-FinFETs), by adopting the direct-current current voltage (DCIV) method and an energy profiling technique. The interface trap generation ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta ~\text{N}_{IT}$ </tex-math></inline-formula> ) and bulk trap generation ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta ~\text{N}_{OT}$ </tex-math></inline-formula> ) are separated from the measured DCIV data and their <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> dependences are independently investigated. The DCIV results indicate that the observed strong <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> dependence of trap generation is primarily attributed to the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> -dependent <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta ~\text{N}_{OT}$ </tex-math></inline-formula> that exhibits a 36% reduction when <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> increases from 10 Hz to 1 MHz. Furthermore, this <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> -dependent <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta ~\text{N}_{OT}$ </tex-math></inline-formula> is mainly distributed between <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\text{E}_{v}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\text{E}_{i}}$ </tex-math></inline-formula> , and exhibits a visible <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f}$ </tex-math></inline-formula> -dependent peak of energy density around <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\text{E}_{c}}$ </tex-math></inline-formula> .