AUXILIARY HEATING DEVICE FOR ZONE MELTING FURNACE AND HEAT PRESERVATION METHOD FOR SINGLE CRYSTAL ROD THEREOF

摘要

The present invention aims at providing an auxiliary heating device for a zone melting furnace and a heat preservation method for a single crystal rod thereof. The auxiliary heating device comprises an auxiliary heater disposed below a high-frequency heating coil inside the zone melting furnace and is formed by winding a hollow metal circular pipe. The winding start end of the auxiliary heater is positioned on the upper part, the winding stop end of the auxiliary heating device is positioned on the lower part, and an upper end part and a lower end part are respectively guided out from the both ends; and a hollow cylindrical heating load is disposed on the inner side of the auxiliary heater, and an insulation part is disposed between the heating load and the auxiliary heater. The present invention can solve the problem of single crystal rod cracking caused by unreasonable distribution of the thermal field and overlarge thermal stress in the growth process of zone-melted silicon single crystals over 6.5 inches.

主权项

1. An auxiliary heating device for a zone melting furnace, comprising an auxiliary heater disposed below a primary heating coil in the zone melting furnace, and characterized in that said auxiliary heater is formed by winding a hollow metal circular pipe according to a spiral line type; the winding start end of the auxiliary heater is positioned on the upper part, the winding stop end thereof is positioned on the lower part, and an upper end part and a lower end part are horizontally guided out from the both ends respectively; a hollow cylindrical heating load which is axially symmetrical is disposed on the inner side of the auxiliary heater, and a hollow cylindrical insulation part is disposed between the heating load and the auxiliary heater; and
the said device also comprises hollow tubular electrodes each of which one end is provided with a water inlet and the other end is connected with the upper end part and the lower end part of the auxiliary heater respectively through metal sealing joints; a cable connecting plate is welded to the side edge of each electrode and is connected with the power control cabinet through a water-cooled cable; and the power control cabinet is sequentially connected with a data analysis module and an infrared temperature measuring instrument through signal lines.