Computational Study of Induction Heating Process in Crystal Growth Systems—The Role of Input Current Shape

Mohammad Hossein Tavakoli,Tayebe Nadery Mostagir

doi:10.4236/csta.2012.13021

Mohammad Hossein Tavakoli, Tayebe Nadery Mostagir

Open Access

https://doi.org/10.4236/csta.2012.13021

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Abstract

A set of 2D steady state finite element numerical simulations of electromagnetic fields and heating distribution for an oxide Czochralski crystal growth system was carried out for different input current shapes (sine, square, triangle and sawtooth waveforms) of the induction coil. Comparison between the results presented here demonstrates the importance of input current shape on the electromagnetic field distribution, coil efficiency, and intensity and structure of generated power in the growth setup.

Highlights

IntroductionRadio frequency induction heating is frequently used in crystal growth technology. The process principle consists of applying an alternating current in a conductor or coil called inductor (RF-coil) that generates an alternating electromagnetic field in the space
Comparison between the results presented here demonstrates the importance of input current shape on the electromagnetic field distribution, coil efficiency, and intensity and structure of generated power in the growth setup
Radio frequency induction heating is frequently used in crystal growth technology

Summary

Introduction

Radio frequency induction heating is frequently used in crystal growth technology. The process principle consists of applying an alternating current in a conductor or coil called inductor (RF-coil) that generates an alternating electromagnetic field in the space. The alternating electromagnetic field induces eddy currents in metal crucible where the crystal material is placed and should be to melt. These currents lead to Joulean heating (RI2) of the crucible in the form of temporal and spatial volumetric heating. Ure 1) on the strength and distribution of the electromagnetic fields and heat generation in a Czochralski setup using the mathematical modeling and computer simulation. It should be noted, that despite of the differences in the patterns, each pattern is periodic. Every non-sinusoidal current pattern consists of a fundamental and a complement of harmonics, which can be considered as a superposition of sine pattern of a fundamental frequency ω and integer multiples of that frequency [8]

Governing Equations

The Calculation Conditions

Results and Discussion

Heat Generation