METHOD OF GROWTH OF MONOCRYSTAL OF SAPPHIRE ON SEED CRYSTAL, WHICH IS REMAINED IN MELT, IN AUTOMATIC MODE

摘要

A method for growing sapphire single crystal on the seed crystal, remaining in the melt, in the automatic mode, comprising vacuum, inoculated and growing a single crystal while reducing the melt temperature, the calculation values ​​of the drawing speed and measuring the growing monocrystal weight, and the identification and compensation of deviations between the measured and set point values geometric forms of a single crystal by controlling the temperature of the melt and the rate of withdrawal in the respective channels automata ble systems, characterized in that the pre-block is introduced into the constants values ​​of the following process parameters: ? T - the maximum allowable gradient scull temperature determined empirically, ° C! tu - constant inertia time scull, determined empirically,,! k1 - constant temperature of the heater, V / ° C, using the formula! ! where Uplavleniya - voltage on the heater corresponding to the melting temperature of the batch, B! Tplavleniya - the melting point of the charge, ° C! Von - vertical movement speed down the seed crystal, m / s! h1 - the distance from the lower end of the seed crystal to the upper edge of the crucible, m! Hm - the depth of the crucible, m! ρp - the density of the melt in kg / m3! Dm - the inner diameter of the crucible, m! hkr - the length of the seed crystal, m! Vcr - given crystallization rate, m / s, selectable empirically according to the requirements for the quality of the single crystal condition 6 10-6≤Vkr≤30 · · 10-6! d - the nominal diameter of the neck of a single crystal, m, range of values ​​which does not affect the quality of a single crystal, but depends on the weight of the single crystal! ρk