改善硅基螺旋电感品质因数的厚铝膜干法刻蚀

Dry Etching of Thick Aluminum Film for Q-improvement of Spiral Inductors on Silicon

提出了一种用于改善硅基螺旋电感品质因数的厚铝膜干法刻蚀技术;这种技术利用氧化硅和光刻胶双层复合掩模来掩蔽厚铝的干法刻蚀,完全兼容于CMOS工艺;应用于双层铝布线,实现了最大厚度达到6μm的顶层铝,显著地减小了螺旋电感的串联电阻,提高了品质因数;该技术同高阻SOI衬底技术相结合,制造的10nH螺旋电感的最大品质因数达到8.6。

A dry etching technique of thick aluminum has been proposed for Q-improvement of spiral inductors on silicon. This technique is fully compatible with conventional CMOS processes by employing silicon oxide and photoresist to mask thick aluminum film during dry etching. It was used in two-layer-aluminum wiring, and the top aluminum layer with the maximum thickness of 6μm was realized, which decreased the series resistance of inductors significantly and improved the quality factors effectively. Especially, combined with a high resistivity SOI substrate, the proposed technique resulted in a very high Q up to 8.6 for the 10 nH inductor.