The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 17, 2002
Filed:
Feb. 26, 2001
Kounosuke Kitamura, Saitama, JP;
Naoki Ono, Saitama, JP;
Mitsubishi Materials Silicon Corporation, Tokyo, JP;
Abstract
A first step models a hot zone in a pulling apparatus of a single crystal as a mesh structure, and a second step inputs physical property values of each member corresponding to meshes combined for each member of the hot zone into a computer. A third step obtains the surface temperature distribution of each member on the basis of the calorific power of a heater and the emissivity of each member, and a fourth step obtains the internal temperature distribution of each member on the basis of the surface temperature distribution and the thermal conductivity of each member, and then further obtains the internal temperature distribution of a molten liquid being in consideration of convection. A fifth step obtains the shape of the solid-liquid interface between the single crystal and the molten liquid in accordance with an isothermal line including a tri-junction of the single crystal. A sixth step repeats said third to fifth steps until the tri-junction becomes the melting point of the single crystal. The invention aims at making the computation result and an actual measurement result of the shape of the solid-liquid interface between a single crystal and a molten liquid coincide very well with each other.