| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device that reduces cracking, missing or chipping of a wafer, and also improves yield of the semiconductor device. SOLUTION: A wafer such as a FZ wafer, a CZ wafer or the like is thermally oxidized to form a thermal oxide film on the entire surface of the wafer. Next, the thermal oxide film formed on a surface of the wafer on which an element structure is formed is removed to form an aperture portion. Next, a high temperature and long time thermal processing is carried out in a non-oxidizing atmosphere, so that internally directional diffusion of atomic oxygen from the thermal oxide film to the wafer is carried out. If the CZ wafer is used as a wafer, externally directional diffusion of the atomic oxygen from the wafer to the interior of the atmosphere is also carried out. Thus, formed is a silicon wafer 1 where a surface of the central portion of the wafer is comprised of a low oxygen concentration silicon layer 2 and further, a bulk region, a backside of the central portion and end of the outer periphery thereof are included in a high oxygen concentration silicon layer 3. Then, the surface element structure is formed on the surface of the central portion of the silicon wafer 1 after the thermal oxide film is removed. COPYRIGHT: (C)2010,JPO&INPIT
|
