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Choice of crucible material is a key issue during the growth of AlN crystal. The stabilities at high temperature and life-spans of boron nitride (BN) crucible,tantalum (Ta) crucible and tungsten (W) crucible were compared. Tantalum crucible behaved worse at high temperature and life-span was shortened as compared with the other two crucible materials. It was very crisp and easy to crack. In contrast,self-seeded AlN crystals with different morphologies could be obtained at different high temperatures using BN crucible. The boron nitride crucible was stable below 2200 ℃,above which it would decompose. Thus it was unsuitable for the bulky AlN crystal growth. Tungsten crucible could endure the temperatures higher than 2200℃. Unfortunately we could only get AlN polycrystallines using tungsten crucible. After 50～100 hours’ run,the crucible was destroyed completely due to the multiple deep cracks. XRD results of destroyed tungsten crucible indicated that the main phases are tungsten carbide and tungsten nitride.
Choice of crucible material is a key issue during the growth of AlN crystal. The stabilities at high temperature and life-spans of boron nitride (BN) crucible, tantalum (Ta) crucible and tungsten (W) crucible were compared. Tantalum crucible behaved worse at high temperature and life-span was shortened as compared with the other two crucible materials. It was very crisp and easy to crack. In contrast, self-seeded AlN crystals with different morphologies could be obtained at different high temperatures using BN crucible. boron carbide crucible was stable below 2200 ° C, above which it would not decompose. Thus it was unsuitable for the bulky AlN crystal growth. Unfortunately we could only get a polycrystalline nitride using tungsten crucible. After 50 ~ 100 hours’ run, the crucible was completely completely due to the multiple deep cracks. XRD results of destroyed tungsten crucible indicated that the main phases are tungsten c arbide and tungsten nitride.