Effects of Surfactant Additives in BHF on Etching and Cleaning Processes

• Main Authors: Liu, Mei Jean, 劉美貞
• Other Authors: Min-Shien Feng, Chang-Ting Chang
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/52950925906689496988

碩士 === 國立交通大學 === 材料科學與工程研究所 === 85 === BHF is a well-known, Excellent wet-etching regent for silicon dioxides. It cannot perform complete cleaning and etching, however,due to its poor wettability on the wafer surface. In this work, we stigate the effect of surfactants additives in BHF on etching and cleaning process of ULSI. The wettability can be improved by the reduction of surfacetension with the addition of surfactants in BHF. Addition of binarysurfactant can reduce surface tension lower than 25 dyne/cm2. The addition of surfactant does not change neither etching rate nor etchingprofiles. The wafer is treated by surfactant BHF is effective reducedthe fluorine coverage that passivated to reoxidation and hydrophobicsurface performs fully. The hydrophobic surface are well to besusceptible to natice oxide form,particle deposition and metallic contamination. Therefore, it can effective reduce the roughness.Thereduction of native oxide growth can decrease the contact resistance.An increase of surface micro-roughness has been confirmed toseverely degrade the electrical performance such as charge tobreakdown Qbd and C- V characteristics. The addition of surfactantsin BHF can smooth the surface and exhibit a excellent behavior in Qbd and C-V characteristics.