Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (28권3호 182-191)

Fabrication and Characteristics of Porous Silicon

다공성 실리콘의 제조 및 특성에 관한 연구

이철환;조원일;백지흠;박성용;안춘호;유종훈;조병원;윤경석;

한국과학기술연구원 화공연구부;(주)실트론 연구소;고려대학교 자연과학대학 물리학과;

Abstract

A highly porous silicon layer was fabricated by anodizing single crystalline silicon in a dilute solution of hydrofluoric acid. The color of the porous silicon changed from red and blue to yellow gold during the anodizing process. The current-voltage (I-V) curve of the anodizing process showed a typical Schottky diode rectification form. The cell voltage decreased with the increase of HF concentration in the solution at high current range. However, the voltage was independent on HF concentration in the solution at low current range. The pore size was dependant on anodizing condition (HF concentration, current and anodizing time). The pore size and wall width of porous silicon layer were 4~6 and 1~3 nm, respectively. Surface of the porous silicon was covered with silicon compound ($SiH_x$etc.) according to IR spectrum analysis. The peak wavelength and width of photoluminescence (PL) spectrum of porous silicon were 650~850 nm (1.5~1.9 eV) and 250 nm, respectively. The photoluminescence intensity and peak wavelength, and porosity of porous silicon increased with increasing anodizing current and decreased with increasing HF concentration in the anodizing solution.

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