Modelling of thermal field and point defect dynamics during silicon single crystal growth using CZ technique

• Published in: Journal of crystal growth 2019-08, Vol.519, p.7-13
• Main Authors: Sabanskis, Andrejs, Virbulis, Janis
• Format: Article
• Language: English
• Subjects: A1. Computer simulation; A1. Heat transfer; A1. Point defects; A1. Thermal stresses; A2. Czochralski method; B2. Semiconducting silicon; Crystal defects; Crystal growth; Crystal pulling; Mathematical models; Point defects; Silicon; Single crystals; Thermal stress
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2019.04.033

•Increased effective ambient temperature ensures growth of vacancy-rich crystals.•The influence of thermal stresses on point defects is stronger for large crystals.•The pull rate drop increases crystal radius, so the heater power has to be adjusted.•A good agreement with experiment is achieved for 50, 100 and 200 mm crystals. Silicon single crystal growth by the Czochralski (CZ) technique is studied numerically using non-stationary mathematical models which allow to predict the evolution of the CZ system in time, including Dash neck, cone and cylindrical growth stages. The focus is on the point defect dynamics, also considering the effect of the thermal stresses. During the cylindrical stage, the crystal pull rate is temporarily reduced as in experiments by Abe et al. The crystal radius and heater power change is explicitly considered in the calculations for crystal diameters of 50, 100 and 200 mm and the agreement with experiments is discussed.