PURPOSE: To speedily analyze the concentrations of components and to simply execute the automatic control of an electroless plating bath by detecting a reducing agent and a complexing agent in the plating bath by an infrared spectroscopic method and calculating and replenishing the necessary quantity thereof.
CONSTITUTION: The electroless plating bath consisting essentially of a metallic salt, a complexing agent forming a complex salt with the metal and a reducing agent are stored in the electroless plating bath 1. A sample of the plating bath is sent to an infrared spectroscope unit 3 to detect the absorbancy thereof in the infrared region. The concentrations of the complexing agent and the reducing agent in the plating bath are calculated in a controlling means 14 based on the detected absorbancy. The necessary quantity is obtained by comparing each of the calculated concentrations with a set concentration for each thereof. Solenoid valves 11, 13 are controlled based on the necessary quantity, thereby replenishing the necessary quantity of the complexing agent and the reducing agent from supply sources 5, 6.
| JPH03238865 | SEMICONDUCTOR ELEMENT |
HAGA MASAKI
NAWAFUNE HIDEMI
MIZUMOTO SHOZO
