Semiconductor substrate, method for fabricating the same, and method for fabricating semiconductor device

1. A method for fabricating a semiconductor device using a semiconductor substrate in which a notch is formed in an edge portion thereof, the notch has two shoulder portions each configured as an arc, a difference in curvature between the two shoulder portions is not less than 0 mm and not more than 0.1 mm, and each of the two shoulder portions has a curvature not less than 0.3 mm and not more than 2.0 mm, the method comprising the steps of:

burying an insulating film or a conductive film in a depressed portion provided in the semiconductor substrate; and

planarizing the insulating film or the conductive film by chemical mechanical polishing.

2. A method for fabricating a semiconductor device using a semiconductor substrate in which a notch is formed in an edge portion thereof, the notch has two shoulder portions each configured as an arc, a difference in curvature between the two shoulder portions is not less than 0 mm and not more than 0.1 mm, and each of the two shoulder portions has a curvature not less than 0.3 mm and not more than 2.0 mm, the method comprising the steps of:

forming an end-point detection film on the semiconductor substrate;

performing etching with respect to the end-point detection film and the semiconductor substrate by using a mask pattern to form an isolation trench;

burying an insulating film in the isolation trench; and

planarizing the insulating film by chemical mechanical polishing.

3. The method of claim 2 , wherein a polishing speed for the insulating film is double or more a polishing speed for the end-point detection film in the step of planarizing the insulating film.

4. The method of claim 2 , further comprising, after the step of planarizing the insulating film, the step of:

polishing the end-point detection film by chemical mechanical polishing.