| 摘要 |
PURPOSE:To obtain an Si wafer of high quality by setting O concentration between lattices and solid solution C concentration in the prescribed ranges when pulling up a single Si crystal by a CZ process in a magnetic field. CONSTITUTION:When a single Si crystal is pulled up by a CZ process in a magnetic field, solid solution O concentration is lowly controlled to suppress a defect, but a heat treatment of long time is required to provide direct gettering effect. O concentration between lattices is set to 6-11X10<17>cm<-3>, C is added to shorten the time, and solid solution C concentration is selected to 2-8X10<16>cm<-3>. Its magnetic field is selected to several thousands gauss as a DC magnetic field, the effects are the same in any direction with respect to pulling direction, and C is directly added in a melt of SiC. According to this constitution, the obtained single Si crystal wafer provides sufficient and ready true gettering effect, suppresses thermal doner, reduces irregular dopant, and suppresses a warpage, thereby obtaining the wafer of high quality. |
