Method and device for producing ultra-pure water having low specific resistance used for washing of wafer, or the like

Abstract

Abstract PURPOSE:To maintain a specific resistance value of ultra-pure water to be ejected onto a wafer surface in a specific range at all times by controlling the blowing rate of the carbon dioxide to be blown and melted into the ultra-pure water to a constant rate. CONSTITUTION:Gaseous carbon dioxide is passed through a filter 5 to have the much higher purity and is then blown through a gas flow passage 10 into an ultra-pure water flow passage 11. A specific resistance value 16 which is the input to a specific resistance adjuster 4 and is the input to a specific resistance value sensor 14 and a specific resistance alarm 15 is disposed on the down stream of the passage 11. When the output from the sensor 14 exceeds the upper limit value in a specific range, a solenoid valve 3 is opened and when the value is a lower limit value or below, said valve is closed. The blowing rate of the gaseous carbon dioxide is thus controlled to a constant rate and the ultra-pure water having a low specific resistance is stably obtd.

Inventors

• 👤 Yoshiharu Oota
• 👤 太田　嘉治
• 👤 Takeo Makabe
• 👤 真壁　猛夫
• 👤 Toshiji Sawada
• 👤 沢田　稔二

Bibliographic Details