Presentation Information
[9p-N302-4]Quality of silicon substrate and point defects: Renaissance (14) Effect of internal thermal stress on point defects
〇Naohisa Inoue1, Shuichi Kawamata1, Shuichi Okusa1 (1.Osaka Metropolitan Univ. Radiation Research center)
Keywords:
silicon crystal,point defects,internal thermal stress
Previously, research on the stress effect on silicon has been on the dislocation.
In 1983, Abe suggested the increase of point defects and grown-in defects by thermal stress during growth. In around 2000, we made phenomenological analysis. Considering the work for formation of negative relaxation volume under the internal compressive stress, the formation enthalpy of vacancy is negative, resulting in the increase of equilibrium concentration, opposite to the
external stress case.
Before such analysis, we treated impurity doping of extremely large or small atom. The analysis gave the equilibrium concentration increase of 0.1-1%.
By using the reported Young’s modulus of 8MPa, calculated increase was about 0.006%.
However, using 1.6x105 MPa reported in 2000, 10 MPa of thermal stress is enough for 0.1 % increase.
In 2014, experimental result supporting our analysis was reported. The break of Voronkov criterion in large diameter crystal, where the simulated critical internal stress was above 5 MPa.
In 1983, Abe suggested the increase of point defects and grown-in defects by thermal stress during growth. In around 2000, we made phenomenological analysis. Considering the work for formation of negative relaxation volume under the internal compressive stress, the formation enthalpy of vacancy is negative, resulting in the increase of equilibrium concentration, opposite to the
external stress case.
Before such analysis, we treated impurity doping of extremely large or small atom. The analysis gave the equilibrium concentration increase of 0.1-1%.
By using the reported Young’s modulus of 8MPa, calculated increase was about 0.006%.
However, using 1.6x105 MPa reported in 2000, 10 MPa of thermal stress is enough for 0.1 % increase.
In 2014, experimental result supporting our analysis was reported. The break of Voronkov criterion in large diameter crystal, where the simulated critical internal stress was above 5 MPa.