Patent · US Expired

Method of and apparatus for controlling floating zone of semiconductor rod

US4866230A · kind A · utility

3Cited by
6References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 11, 1987
Grant dateSep 12, 1989
Priority date
Expiry dateDec 11, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T117/1008
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

In a method of controlling a floating zone of a semiconductor rod of the present invention shown in FIG. 1, the diameter D.sub.s at a crystallization boundary of a crystal and the axial length of the floating zone are indirectly controlled by controlling a diameter D.sub.m of a crystallizing-side melt shoulder portion and the diameter D.sub.n of a constricted melt portion, respectively. Since these diameters D.sub.m and D.sub.n are used for predicting D.sub.s 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 D.sub.s 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 D.sub.s at the crystallization boundary of the crystal is directly or indirectly controlled by regulating the electrical power supplied to the heater.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.