| 摘要 |
PURPOSE: To prevent an epitaxial crown from being generated by polishing the angle of the front and rear surfaces of a wafer outer-periphery edge part with a specific tool and making the length of the front surface inclined part to be longer than a rear-surface inclined part in the sectional shape of a wafer edge, where an inclined part is formed. CONSTITUTION: A wafer 10 is shaped by a tool 60, so that it has a front surface inclined part 50 with a length 52, a rear surface inclined part 54 with a length 56, and a nose part 58, and the length 52 of the front surface inclined part 50 is reduced, as compared with the length 56 of the rear surface inclined part 54. A groove 62 of the tool 60 consists of a side wall 70 with a length 72 and a sidewall 74 and a bottom part 78 with a length 76. A width 80 of the groove 62 is at least equal to a thickness 22 of the wafer, and a surface 82 is shorter than an adjacent surface 70 by a length 84. Then, the wafer 10 for which a corner has been polished by the tool 60 prior to epitaxial deposition does not cause an epitaxial crown, and has a uniform epitaxial layer 88 on a front surface 12, and a round epitaxial region 90 is formed at the inclined part 50 and the nose part 58, thus improving the yield of a device and an IC. |
