Growth and Evaluation of Bulk GaN Crystals Grown on a Point Seed Crystal by Ba-Added Na Flux Method

ABSTRACTBulk GaN crystals up to several mm in size, grown by a Na/Ga flux method, have been characterized using room and low temperature photoluminescence (PL) and panchromatic cathodoluminescence (CL) imaging. Highly resolved excitonic PL spectra are obtained for material grown in a new, large-scale reactor. The crystal polarity affects the incorporation of residual Zn and Mg or Si acceptors and the deep level luminescence bands in c-oriented platelets. A Zn (A°,X) triplet structure with unusual thermalization properties and a highly resolved structural defect related PL peak are observed. Striations are found in some of the smaller platelets by CL imaging, but are absent in the prismatic crystals.

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Centimeter-Sized Bulk GaN Single Crystals Grown by the Na-Flux Method with a Necking Technique

Crystal Growth & Design ◽

10.1021/cg300643r ◽

2012 ◽

Vol 12 (7) ◽

pp. 3799-3805 ◽

Cited By ~ 33

Author(s):

Mamoru Imade ◽

Kosuke Murakami ◽

Daisuke Matsuo ◽

Hiroki Imabayashi ◽

Hideo Takazawa ◽

...

Keyword(s):

Single Crystals ◽

Flux Method ◽

Bulk Gan

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LPE Growth of Bulk GaN Crystal by Alkali-Metal Flux Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.1245 ◽

2008 ◽

Vol 600-603 ◽

pp. 1245-1250 ◽

Cited By ~ 1

Author(s):

Fumio Kawamura ◽

Hidekazu Umeda ◽

Masanori Morishita ◽

Ryohei Gejo ◽

Masaki Tanpo ◽

...

Keyword(s):

Dislocation Density ◽

Secondary Ion Mass Spectrometry ◽

Impurity Content ◽

Single Crystal Substrate ◽

Flux Method ◽

Low Dislocation Density ◽

Bulk Gan ◽

New Apparatus ◽

Metal Flux ◽

Gan Crystal

We succeeded in growing a GaN single crystal substrate with diameter of about two inches using the Na flux method. Our success is due to the development of a new apparatus for growing large GaN single crystals. The crystal grown in this study has a low dislocation density of 2.3×105 (cm-2), The secondary ion mass spectrometry (SIMS) technique demonstrates that the Na element is difficult to be taken in the crystal in both the + and – c directions, resulting in a Na concentration of 4.2 × 1014 (cm-3) in the crystal. Our success in growing a two-inch GaN substrate with a low impurity content and low dislocation density should pave the way for the Na flux method to become a practical application.

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