| 摘要 |
PROBLEM TO BE SOLVED: To form a groove simply and to reduce the cost of it by forming the back surface of a diffused resistor that is to detect the change of resistance by displacement thinner by machining and using electrolyzation for a cutting edge or an electrophoretic phenomenon of cutting abrasive grains in a machining. SOLUTION: A diffused resistor 2 is formed on a semiconductor substrate 1 and passivation is formed on the upper layer of it. The back surface of the diffused layer is mechanically worked thinner with a rotating cutter blade 5 from the back surface of the diffused layer. Colloidal silica is used with the cutting liquid and the blade 5 is electrolyzed by applying direct current to it. The blade 5 cuts the semiconductor substrate 1. The silica particles 3 of the colloidal silica are adhered to the blade 5 and the silica particles 3 touch the semiconductor substrate 1. With this, a diaphragm part is formed so that a groove 7 without deteriorated layer on it by the mechanical work is formed as the groove 7. With such working method, work steps are decreased and the cost of the machining work can be reduced. |
