MANUFACTURE OF SEMICONDUCTOR TYPE GAS SENSOR

• Main Author: FUKUI KIYOSHI
• Format: Patent
• Language: English
• Published: 01.11.1989
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

PURPOSE:To make it possible to form stably a reformed metal layer characterized by high dispersion and high density as a modifying material on the entire surface part of an induction layer, by immersing the induction layer in an electrolyte incorporating modifying metallic ions, and performing electrodeposition of the metal. CONSTITUTION:An induction layer 2 comprises a tin oxide semiconductor which is formed in a spherical shape by sintering under the state wherein a platinum coil 1 is embedded at the central part. A pair of nickel pins 3 are fixed in an insulating layer 7. Both ends of the platinum coil 1 are brought into contact with the pair of the nickel pins 3. Under this state, the induction layer 2 is immersed into an electrolyte 5 incorporating modifying metallic ions. The metal undergoes electrodeposition on the surface part with the electrolyte. As a result, the metal is uniformly dispersed on the entire surface part 2. The metal does not infiltrate in the deep part. The metal is supported in the very shallow layer from the surface at a high density.