The Durability of Various Crucible Materials for Aluminum Nitride Crystal Growth by Sublimation


B. Liu, J.H. Edgar, Z. Gu, D. Zhuang
Department of Chemical Engineering, Kansas State University

B. Raghothamachar, M. Dudley
Department of Materials Science Engineering, State University of New York at Stony Brook

A. Sarua, Martin Kuball
University of Bristol, H. H. Wills Physics Laboratory

H. M. Meyer III
Oak Ridge National Laboratory, High Temperature Materials Laboratory

This article was received on Monday, July 12, 2004 and accepted on Wednesday, October 20, 2004.

Abstract

Producing high purity aluminum nitride crystals by the sublimation-recondensation technique is difficult due to the inherently reactive crystal growth environment, normally at temperature in excess of 2100 °C. The durability of the furnace fixture materials (crucibles, retorts, etc.) at such a high temperature remains a critical problem. In the present study, the suitability of several refractory materials for AlN crystal growth is investigated, including tantalum carbide, niobium carbide, tungsten, graphite, and hot-pressed boron nitride. The thermal and chemical properties and performance of these materials in inert gas, as well as under AlN crystal growth conditions are discussed. TaC and NbC are the most stable crucible materials with very low elemental vapor pressures in the crystal growth system. Compared with refractory material coated graphite crucibles, HPBN crucible is better for AlN self-seeded growth, as crystals tend to nucleate in thin colorless platelets with low dislocation density.

Outline

  • Introduction
  • Background
  • Thermodynamic Calculations
  • Crystal growth
  • Experimental procedure and characterization
  • Growth of AlN in TaC coated graphite crucible
  • Growth of AlN in NbC coated graphite crucible
  • Growth of AlN in tungsten crucible
  • Growth of AlN in graphite crucible
  • Growth of AlN in HPBN crucible
  • Conclusions and future work
  • Acknowledgments
  • Linked Pages

    Cite this article as: MRS Internet J. Nitride Semicond. Res. 9, 6(2004).

    last updated Thursday, October 21, 2004 3:10:56 PM.

    © 2004 The Materials Research Society MRS Internet Journal of Nitride Semiconductor Research