Apparatus and method for improved washing and drying of semiconductor wafers

摘要

Apparatus and method are provided for improved washing and drying of semiconductor wafers utilizing an enhanced "Marangoni effect" flow of liquid off of the wafers for superior prevention of watermarks (water spots) on integrated circuits (ICs) on the wafers. The apparatus includes a housing 12 which may be hermetically sealed, an open-top wash tank 60 within a lower part of the housing, a moveable rack 16 for holding the wafers either in the tank for washing or in an upper part of the housing for drying, apparatus 34 for supplying chilled (near freezing) de-ionized water (DIW) to a lower part of the tank, the DIW flowing within the tank and overflowing the top thereof, a pump 20 for draining overflowing DIW from the housing, and apparatus 40 for supplying to the housing organic vapor such as isopropyl alcohol (IPA) in a dry gas such as nitrogen. During wafer drying operation of the apparatus the pressure within the housing is kept at about one Torr or less.