Guideline to obtain a point defect-free Si ingot based on the zero cross-point (Cp = 0) control using Si melt growth

Abstract

  The critical point at which vacancy (C_V) and interstitial Si atom (C_I) concentrations have minimum values is generally used to obtain a high-quality Si single ingot by the Czochralski (Cz) method. But the growth method is not stable at the view point of obtaining the minimum limit of remained C_V and C_I concentrations. The reason why the critical point varies depending on temperature is that each critical point exactly corresponds to each cross point (Cp) of the C_V and C_I concentration curves. To obtain the minimum limit of the C_V and C_I concentrations, Nakajima has implemented the Cp=0 control at which the C_V and C_I concentrations have practically minimum limit values (C_V = C_I = 0) because the pair annihilation is finished at the Cp = 0. The Cp = 0 point is fully compatible to the perfect critical point where both C_V and C_I are practically zero.