| 摘要 |
PURPOSE:To obtain an optimal hardening process of a thick resist film dealing with the impurity ion implantation into a semiconductor substrate under high acceleration voltage by heating the resist film while setting the pressure in a furnace higher than the atmospheric pressure and gradually lowering the pressure at a moment when the temperature of the resist film reaches a set level. CONSTITUTION:A semiconductor substrate 3, i.e., an Si wafer, is set in a resist hardening equipment comprising a baking unit. The pressure is then increased to 5-10 atmospheric pressure and the semiconductor substrate 3 is heated up to about 10 deg.C. When it is heated up to about 110 deg.C, the pressure is lowered gradually and the semiconductor substrate 3 is heated for about 30min. Consequently, solvent in the resist film 1 is evaporated gradually thus sustaining the original pattern of resist film 1. Subsequently, the pressure is lowered and the temperature of the semiconductor substrate 1 is lowered thus completing the hardening process of the resist film 1. This method allows hardening of resist film while protecting the resist film against rupturing. |
