Shear stress threshold for dislocation generation from internal source for silicon specimens heat treated in different modes [20]: (1) as-grown; (2) 1000 °C/15 min + 450 °C/16 h; (3) 1000 °C/15 min + 650 °C/16 h; (4) 1000 °C/15 min + 650 °C/16 h + 800 °C/4 h + 1000 °C/4 h; (5) 1000 °C/15 min + 450 °C/16 h + 650 °C/16 h + 1000 °C/4 h.