JPS649624A - Method of drying semiconductor device - Google Patents

Abstract

PURPOSE:To make it possible to dry quickly without enriching and concentrating impurities in liquid and in the surface of a semiconductor device to a concentration which poses problems in manufacturing and operation of the semiconductor device, by replacing water droplets, which are attached to the semiconductor device after washing with water, by liquid whose vapor pressure is higher than water, and freezing and drying the droplets in vacuum. CONSTITUTION:A semiconductor device 11 after washing with water is placed beneath nozzles 14. Liquid, e.g., 2-propanol or acetone, whose compatibility with water is high and vapor pressure is higher than that of water, is atomized through the nozzles 14. Water droplets, which are attached to the semiconductor device 11, are replaced. The semiconductor device 21, to which the droplets of the substituted liquid are attached, is moved to a stage 22 and cooled. Thus the attached liquid droplets are frozen. Then, a valve 27 is opend, and a gas in a chamber 23 is exhausted through an exhaust port 25. The inside is made to be a vacuum state, and the semiconductor device 21 is dried. At this time, the frozen liquid droplets are sublimated like the liquid droplets 4a-4c. Therefore, the impurities in the attached liquid are sublimated or remain at planar positions like arrows 5a-5c. The impurities are not enriched and concentrated to a concentration, which poses problems in manufacturing and operation of the semiconductor device. Since the water is replaced by, e.g., 2-propanol or acetone, whose vapor pressure, is higher than that of water, the device can be dried 3-4 times faster than the case, in which water is frozen and dried.