AVS 52nd International Symposium
    Plasma Science and Technology Monday Sessions
       Session PS-MoP

Paper PS-MoP8
Effective Stripping of Heavily Implanted Photoresist by Insitu-Bake Process

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Plasma Science and Technology Poster Session
Presenter: S.G. Park, Inha University, Korea
Authors: S.-K. Yang, Inha University, Korea
J. Yang, PSK Inc.
S.G. Park, Inha University, Korea
Correspondent: Click to Email
Popping of heavily implanted photoresist during plasma stripping, which is the main source of particulate contamination, occurs during the conventional stripping process using oxygen radicals at the temperature range of 250°C or higher. We introduce in-situ bake process (ISBP) prior to oxygen plasma stripping which does not suffer from low ashing rate or substrate damage. It is found that baking wafers at 250°C in the atmospheric pressure before evacuating the process chamber accelerates outgassing from bulk of photoresist without popping. Since heat transfer from heating wafer stage to wafer is better in air than that in vacuum, the stripping rate is also increased 50% because time to reach the process temperature is reduced. In this paper, we show the evidence of no-popping during bake-in-air step and the surface modification by bake-in-air by XPS analysis of carbon bonding. XPS data shows that baking in vacuum enhances more amorphous carbons in the photoresist surface than baking in air.