四甲基氢氧化铵:异丙醇:水系统对硅的各向异性腐蚀

Anisotropic Etching of Silicon With TMAHW∶IPA

本文研究了在25%的四甲基氢氧化铵水溶液(TMAHW)中加入异丙醇(IPA)构成的腐蚀系统对硅的各向异性腐蚀特性.研究发现:在异丙醇含量从0%到80%体积比的广大范围内,溶液对硅均有显著的腐蚀作用,且表面质量比纯TMAHW的更好.实验给出了腐蚀速率、削角比和各向异性比R_(100)/R_(111)等参数与IPA含量的关系,结果表明:50%体积IPA与50%体积TMAHW构成的溶液存在腐蚀速率的极大值、削角的极小值和最大的各向异性比及R_(100)/R_(111).因之按此比例配制的新腐蚀液具有表面质量好,与MOS工艺相容以及低成本的优点.

Characteristics of anisotropic etching of silicon in TMAHW: IPA system areinvestigated. Obvious etching action and good surface quality are observed when thecontents of IPA vary from 0% to 80% by volume. The experimental results of etchingrate, undercutting ratio and ratio of R100/R111 50% vol. IPA and 50% vol. TMAHW isrecommended for maximum etching rate, minimum undercutting ratio and maximumR100/R111 ratio. The new etchant features excellent surface quality, MOS processcompatibility and low cost.