METHOD OF AND APPARATUS FOR CONTROLLING FLOATING ZONE OF SEMICONDUCTOR ROD

摘要

In a method of controlling a floating zone of a semiconductor rod of the present invention shown in Fig. 1, the diameter Ds at a crystallization boundary of a crystal and the axial length of the floating zone are indirectly controlled by controlling a diameter Dm of a crystallizing-side melt shoulder portion and the diameter Dn of a constricted melt portion, respectively. Since these diameters Dm and Dn are used for predicting Ds and L to be obtained after a given time has passed, the response speed and stability of the control are improved as compared with the direct control of Ds and L. An apparatus for controlling a floating zone of a semiconductor rod of the present invention performs the above-described method. In another method, the zone length is directly or indirectly controlled by regulating a relative moving speed of the melting-side semiconductor rod relative to the heater, and the diameter Ds at the crystallization boundary of the crystal is directly or indirectly controlled by regulating the electrical power supplied to the heater.