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Group-III nitride heteroepitaxial films approaching bulk-class quality


III-nitride wide bandgap semiconductors are promising materials for modern optoelectronics and electronics. Their application has progressed greatly thanks to the continuous quality improvements of heteroepitaxial films grown on large-lattice-mismatched foreign substrates. But compared with bulk single crystals, there is still tremendous room for the further improvement of the material quality. Here we show a paradigm to achieve high-quality III-nitride heteroepitaxial films by the controllable discretization and coalescence of columns. By adopting nano-patterned AlN/sapphire templates with regular hexagonal holes, discrete AlN columns coalesce with uniform out-of-plane and in-plane orientations guaranteed by sapphire nitridation pretreatment and the ordered lateral growth of cleavage facets, which efficiently suppresses the regeneration of threading dislocations during coalescence. The density of dislocation etch pits in the AlN heteroepitaxial film reaches 3.3 × 104 cm−2, close to the present available AlN bulk single crystals. This study facilitates the growth of bulk-class quality III-nitride films featuring low cost and scalability.

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Fig. 1: Schematic illustration of AlN growth on NPATs.
Fig. 2: Orientation control during AlN coalescence on NPATs and NPSSs.
Fig. 3: Crystalline quality of AlN on NPATs.
Fig. 4: Performance of DUV-LEDs fabricated on NPATs.

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Data shown in the main text have been made available through Figshare ( Data are also available from the corresponding authors upon reasonable request. Source data are provided with this paper.


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This work was supported by the National Key Research and Development Program of China (2022YFB3605100 to J.W.), the National Natural Science Foundation of China (62234001 and 61927806 to B.S.; 61974002 and 62135013 to F.X.), the Key-Area Research and Development Program of Guangdong Province (2020B010172001 to B.S.) and the Major Scientific and Technological Innovation Project (MSTIP) of Shandong Province (2019JZZY010209 to F.X.).

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Authors and Affiliations



J.W., N.X. and F.X. conceived the experiments. J.W., N.X. and L.Z. grew the samples and performed relevant measurements. F.X., X.Y., N.T., X.W., W.G. and B.S. provided support in the measurement and analysis. J.L. performed device fabrication under X.K.’s and Z.Q.’s supervision. J.W. wrote the manuscript with the assistance of F.X., W.G. and B.S. All authors discussed the results and commented on the manuscript.

Corresponding authors

Correspondence to Fujun Xu or Bo Shen.

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Nature Materials thanks Xiaohang Li, Steven DenBaars and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–20.

Source data

Source Data Fig. 1

XRD φ-scan of AlN template.

Source Data Fig. 2

Convergent beam electron diffraction cross-correlation analyses.

Source Data Fig. 3

Transmission spectrum and Raman shift of AlN on NPATs.

Source Data Fig. 4

Performance of DUV-LEDs fabricated on NPATs.

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Wang, J., Xie, N., Xu, F. et al. Group-III nitride heteroepitaxial films approaching bulk-class quality. Nat. Mater. 22, 853–859 (2023).

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