| 摘要 |
PROBLEM TO BE SOLVED: To evalute the unsatisfactory state of a semiconductor manufacturing process by a method wherein an insulating film is formed on a wafer for monitor, a test on the characteristics of the insulating film is made, and a mixing of impurities into the wafer for monitor associated with the semiconductor manufacturing process is detected as a variation of the characteristics of the insulating film. SOLUTION: In a wafer 50 for monitor, a buried oxide film 2 is formed on a silicon substrate 1 and an SOI layer 3 is formed on the film 2. After the upper surface of this layer 3 is cleaned, a silicon oxide film 4 is formed on the layer 3 by a thermal oxide method. When a cleaned layer and an oxidation furnace are deteriorated, impurities 5 are made to mix within the interface between the layer 3 and the film 4 and in the film 4 to store the impurities 5. In this sate, it is detected that a polysilicon film 6 is formed on the film 4 to evalute the characteristics of the film 4, and the characteristics obtained by the evaluation are varied from the characteristics obtained at a normal time.
|
