摘要 |
A control system for controlling the operation of an apparatus for growing tubular crystalline bodies. The control system comprises a weight sensor for measuring the weight of the crystal, a length sensor for measuring the length of the crystal, a pressure sensor for measuring the pressure inside the crystal, and a controller coupled to the weight, length and pressure sensors for controlling the operation of the crystal growing apparatus. The controller is coupled to the die heater of the apparatus for controlling the temperature of melt contained in the crucible of the apparatus based on the outputs of the weight, length and pressure sensors. To ensure the wall of the tubular crystalline body is maintained at a substantially uniform thickness, precise measurement of the weight of the body must be made. Compensation is provided by this invention for weight measurement errors that are created by pressure fluctations within the tubular crystalline body.
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