Issue 35, 2018

Numerical study on the effect of additional resistive heating and crystal rotation on sapphire single crystals (Al2O3) grown by the Kyropoulos method

Abstract

In this paper, numerical simulations were performed to investigate the effects of additional heating and crystal rotation on Kyropoulos (Ky) sapphire crystal growth for different crucible corner shapes. The present model takes into account induction heating, resistive heating, heat transfer by conduction in all furnace parts, free convection in the melt, radiation exchange between inner furnace surfaces, thermo-capillary at the melt-free surface, internal radiation inside the sapphire crystal and phase change. The computational results show the advantage of using the additional heating and crystal rotation especially when a slipped crucible bottom corner is used. The crucible with slipped and curved corner shapes decreases both the convexity of the melt–crystal interface and the flow intensity of the molten sapphire more than the cylindrical crucible does. The convexity of the melt–crystal interface is reduced by 22%, 24% and 26% when additional heating is used and by 38%, 44% and 48% when this heating is used with crystal rotation for cylindrical, curved and slipped crucible bottom shapes, respectively. A less convex and more stable growth interface can be obtained when using the slipped crucible bottom shape and additional heating at the crucible bottom for a given crystal rotation rate.

Graphical abstract: Numerical study on the effect of additional resistive heating and crystal rotation on sapphire single crystals (Al2O3) grown by the Kyropoulos method

Article information

Article type
Paper
Submitted
12 Jun 2018
Accepted
07 Aug 2018
First published
07 Aug 2018

CrystEngComm, 2018,20, 5220-5227

Numerical study on the effect of additional resistive heating and crystal rotation on sapphire single crystals (Al2O3) grown by the Kyropoulos method

S. Zermout, F. Mokhtari, A. Nehari and I. Lasloudji, CrystEngComm, 2018, 20, 5220 DOI: 10.1039/C8CE00972D

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements