Presentation Information
[8p-E308-9]Quality of silicon substrate and point defects: Renaissance (16) Effect of pressure and stress on point defects
〇Naohisa Inoue1, Shuichi Kawamata1, Shuichi Okuda1 (1.Osaka Metropolitan Univ. Radiation Research Center)
Keywords:
silicon crystal,point defects,internal thermal stress
Abe suggested the increase of vacancy type defects in large diameter silicon crystal in 1990. In 1999, we performed the phenomenological analysis using the stress simulation result of 0.3MPa. The concentration increase obtained by equation including the relaxation volume VR was 0.006%, much smaller than the critical value of 0.1-1%, obtained for the doping effect of large/small atomic diameter. However, in 2001 the new simulation was reported where the stress is 10MPa for 300 mm crystal. Using this, the stress was calculated to be 0.1%, large enough for the void defect formation. In 2011, Vanhellemont made the similar analysis, but using Voronkov’s criterion. He made two mistakes, using equation for the pressure effect. Using formation volume V and 12MPa, interstitial (not vacancy!) increase was calculated to be 0.5%, the number being not so different from ours. In 2015 Nakamura showed the deviation from Voronkov criterion at about 5MPa simulated.