An improved TMAH Si-etching solution without attacking exposed aluminum

doi:10.1016/S0924-4247(00)00546-X

CORC > 北京大学 > 信息科学技术学院

	An improved TMAH Si-etching solution without attacking exposed aluminum
	Yan, GZ ; Chan, PCH ; Hsing, IM ; Sharma, RK ; Sin, JKO ; Wang, YY
刊名	sensors and actuators a physical
	2001
关键词	TMAH aluminum micro-electromechanical system SILICON
DOI	10.1016/S0924-4247(00)00546-X
英文摘要	In MEMS fabrication technology, it is often desirable to etch silicon substrate or polysilicon sacrificial layer after metallization is completed. Most of the etching solution would attack the aluminum. In this paper, an improved tetramethyl ammonium hydroxide (TMAH) etching method is reported. The advantages of the process are to achieve high silicon etching rate (0.9-1.0 mum/min at 85 degreesC) and smooth silicon surface (less than 0.2 mum root-mean-square). Another important advantage is that no significant aluminum etching is observed during this process. The etchant used in the study consists of 5 wt.% TMAH solution, 1.4 wt.% (or above) dissolved silicon, and oxide 0.7 wt.% (NH4)(2)S2O8 ammonium peroxodisulfate. The aluminum etching rate is significantly reduced by the addition of the ammonium peroxodisulfate, which also significantly improved the silicon surface roughness. When dissolving a suitable amount of silicon in TMAH etchant, along with a suitable amount of ammonium peroxodisulfate. the aluminum etching rate is reduced to zero. After TMAH etching the aluminum surfaces are protected by the coating of by-products, which prevents the underlying aluminum film from being etched by TMAH solution. The etching process demonstrated in this work is readily applicable to MEMS (micro-electromechanical system) device fabrication, such as polysilicon sacrificial layer removal, after the metallization is completed. (C) 2001 Elsevier Science B.V. All rights reserved.; Engineering, Electrical & Electronic; Instruments & Instrumentation; SCI(E); EI; 57; ARTICLE; 1-2; 135-141; 89
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/211293]
专题	信息科学技术学院
推荐引用方式 GB/T 7714	Yan, GZ,Chan, PCH,Hsing, IM,et al. An improved TMAH Si-etching solution without attacking exposed aluminum[J]. sensors and actuators a physical,2001.
APA	Yan, GZ,Chan, PCH,Hsing, IM,Sharma, RK,Sin, JKO,&Wang, YY.(2001).An improved TMAH Si-etching solution without attacking exposed aluminum.sensors and actuators a physical.
MLA	Yan, GZ,et al."An improved TMAH Si-etching solution without attacking exposed aluminum".sensors and actuators a physical (2001).