High Performance Spiral Inductor on Deep-Trench-Mesh Silicon Substrate

Abstract

This letter presented the octagonal spiral inductors on deep-trench-mesh substrate which obtained a high self resonant frequency (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">res</sub> ) and high peak quality factor (Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak</sub> ) in a 0.35-mum 3P3M SiGe BiCMOS process. The main advantages of the deep-trench-mesh structure were twofold: 1) deep-trench-mesh pattern decreased capacitive coupling and increased f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">res</sub> by 10% compared to a conventional structure and 2) decreased resistive losses and increased Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak</sub> around 15%. The overall figure-of-merit was improved by 28% while dealing with Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak</sub> , f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">res</sub> , and chip area. Meanwhile, a broad Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak</sub> frequency response was found in deep-trench-mesh inductors