| abstract |
A method and an apparatus for detecting the crack of a heater of an acid and rinse bath, acid and rinse bath is filled with acid solution, a heater is used to heat the acid solution. A heater is constituted of a hollow quartz tube with one closed end and one open end, the closed end is submerged into acid solution, part of the quartz tube is exposure in the air. The heated filament is inserted into the open end of the heater through the closed end of the heater, moisture detecting device is attached on the inner side wall of the quartz tube, use chemicals that will change color by absorbing moisture, or use electronic component to detect the humidity, monitoring the variation of moisture in the quartz tube to acknowledge is there any crack of the quartz tube, and replace the defect quartz tube before too late. |