title: Selective etching of n-type silicon in pn junction structure in hydrofluoric acid and its application in silicon nanowire fabrication.
abstract: Boron is selectively implanted on the surface of an n-type silicon wafer to form a p-type area surrounded by an n-type area. The wafer is then put into a buffered oxide etch solution. It is found that the n-type area can be selectively etched without illumination, with an etching rate lower than 1 nm min(-1), while the p-type area can be selectively etched under illumination with a much higher etching rate. The possible mechanism of the etching phenomenon is discussed. A simple fabrication process of silicon nanowires is proposed according to the above phenomenon. In this process only traditional micro-electromechanical system technology is used. Dimensions of the fabricated nanowire can be controlled well. A 50 nm wide and 50 nm thick silicon nanowire has been formed using this method.
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China.
authors.forename: Huiquan
authors.initials: H
authors.lastname: Wang
authors.forename: Zhonghe
authors.initials: Z
authors.lastname: Jin
authors.forename: Yangming
authors.initials: Y
authors.lastname: Zheng
authors.forename: Huilian
authors.initials: H
authors.lastname: Ma
authors.forename: Tie
authors.initials: T
authors.lastname: Li
authors.forename: Yuelin
authors.initials: Y
authors.lastname: Wang