| 摘要 |
PURPOSE:To improve the sensitivity and responsiveness as a sensor for various purposes, avoid the migration of electrodes and maintain the bonding strength by a method wherein minute quality parts made of minute quality ceramics are provided on both the sides of a porous part made of porous ceramics and unified together by sintering and electrode films are formed on the outside surfaces of the minute quality parts. CONSTITUTION:A positive characteristic thermistor which is made of semiconductor ceramics and has resistance-temperature characteristics wherein the thermistor is transformed from a conductor into an insulator at a predetermined temperature is composed of a porous part 2 made of porous ceramics, minute quality parts 3 made of minute quality ceramics provided on both the sides of the porous part 2 and unified with it by sintering and external electrodes 4 formed on the outside surfaces of the minute quality parts 3. For instance, a green sheet for the porous part made of BaTiO3 semiconductor ceramics is sandwiched by green sheets for the minute quality parts also made of BaTiO3 ceramics and all the green sheets are laminated and compression-bonded along the direction of lamination and the laminated unit is cut into predetermined dimensions to form rectangular parallelepiped ceramica green compacts. Then the ceramics green compact is sintered to form a sintered unit. Ohmic Ag paste is applied to both the surfaces of the sintered unit and baked to form the external electrode films 4. |
