| 摘要 |
PROBLEM TO BE SOLVED: To provide a quality evaluation method wherein oval pits, pits in a shape of a plurality of ovals being overlapped, and pits having cracks extending from portions at which the plurality of ovals are overlapped are counted in an interstitial excessive-silicon region, in addition to conventional flow-pattern defects and Secco-etched pit defects, threby quality of a silicon wafer is evaluated in a simple method and for a short time, and boundaries of the region is also evaluated and discriminated. SOLUTION: In the quality evaluation method of a silicon wafer, the silicon wafer is cut out from a silicon single crystal; and cutting stress induced during the cutting operation is removed by a mixed solution of fluorinated acid and nitric acid; next the wafer is dipped in a mixed solution of fluorinated acid and nitric acid, then dipped in dilute fluorinated acid, and then dipped in a mixed solution of hydrofluoric acid and potassium dichromate solution; and then oval pits, pits in a shape of a plurality of ovals being overlapped, and pits having cracks extending from portions at which the plurality of ovals are overlapped, which appear on a surface of the wafer, are counted, thereby the quality of a silicon wafer in an interstitial, excessive silicon region is evaluated. COPYRIGHT: (C)2006,JPO&NCIPI
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