Czochralski growth technique

Process Stability and Control. Operationally, automatic control of the crystal radius by varying either the input power to the heater or the crystal pull rate has been necessary for the reproducible growth of crystals with constant radius. Techniques for automatic diameter control have been used since the establishment of Czochralski growth. Optical imaging of the crystal or direct measurement of the crystal weight has been used to determine the instantaneous radius. Hurle (156) reviewed the techniques currently used for sensing the radius. Bardsley et al. (157,158) described control based on the measurement of the crystal weight. 

Table 5.2 Comparison of the Different Time Scales for Different Materials and Growth Techniques for Typical Crystal Dimensions L (Radius), Growth Rates R, and Axial Temperature Gradients in the Crystal G Cz = Czochralski-Type, B = Bridgman-Type,...

Abbreviations used ACRT - Accelerated Crucible Rotation Technique, CZG - Czochralski Growth, EV Growth, HPS-High-pressure Solution Growth, HYG - Hydrothermal Growth, LPE-Liquid Phase Epitaxy. 

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