Patent ID: 6129091
Filing Date: 2000-10-10
Classification: H01L

Abstract:
A method for removal of adsorbed ionic species from silicon pockets in a silicon wafer after reactive ion etching comprising:(a) providing a silicon wafer having freshly etched silicon pockets;(b) performing a first step of treating said silicon wafer with a first solution containing hydrofluoric acid and a surfactant;(c) performing a second step, sequentially from said first step, of removing said silicon wafer from said first solution and, with dispatch and while still wet, rinsing said silicon wafer with de-ionized water;(d) performing a third step, sequentially from said second step, of transferring and immersing said silicon wafer while still wet, and with dispatch, into a second solution containing hydrogen peroxide and ammonium hydroxide, whereby adsorbed ionic species are drawn out from said pockets;(e) performing a fourth step, sequentially from said third step, of transferring said silicon wafer while still wet to a rinse bath and, rinsing said silicon wafer with de-ionized water; and(f) performing a fifth step, sequentially from said fourth step, of drying said silicon wafer.