Papers by Author: Geun Min Choi

Abstract: Space alternated phase shift (SAPS) megasonic technology incorporating with functional water, with dissolving gases H₂ or N₂, was applied to remove fine particle in wet cleaning processes of semiconductor manufacturing in this study. The performances of particle removal were investigated quantitatively by varying the parameters of functional water and megasonic energy. The optimized cleaning performance was further proved with significant yield improvement of mass production by comparison with other main cleaning technology.

Abstract: With scaling of ULSI devices, the process temperatures are continuously lowered. The oxide films, which were deposited at low temperature, show fast etching rates during wet etching compared to high temperature films. Also, the etch rates differ largely from other film deposition conditions. In order to overcome these etch rate differences during surface preparation, dry cleaning processes had been introduced where the etch selectivity of the soft oxide films to the thermal oxide are very similar, regardless of the film deposition conditions and the deposition temperature.

Abstract: This study deals with drying induced water marks dependency on the last cleaning methods, substrate conditions, and drying pre-step delaying times, which are supposed to become a big issue with down scaling of device geometry. The data show that water marks induced by drying failure increase with increasing contact angle on the various surfaces. They are mainly composed of either silicon oxide only or silicon oxide with organic compounds. The former is removed by a dilute HF and/or hot SC-1 treatment and the latter is removed by organic removal cleaning followed by dilute HF etching.