2014 article

Properties of AlN based lateral polarity structures

PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 11, NO 2, Vol. 11, pp. 261–264.

By: R. Kirste n, S. Mita*, M. Hoffmann n, L. Hussey n, W. Guo n, I. Bryan n, Z. Bryan n, J. Tweedie n ...

author keywords: lateral polarity structures; quasi-phase matching; N-polar; columnar growth
Source: Web Of Science
Added: August 6, 2018

AbstractGrowth and characterization of AlN based lateral polarity structures (LPS) are presented. The LPS were grown by MOCVD using patterned low temperature AlN/sapphire substrates: the Al‐polar and N‐polar AlN grew on AlN buffer layer and nitrided sapphire, respectively. AFM images showed a height difference between the two adjacent domains of different polarity on the order of 30 nm, which was equivalent to the low temperature AlN buffer layer thickness. SEM images provided an insight in the growth mode of the two polarities. It was shown that Al‐polar AlN grew two‐dimensionally, leading to a smooth well coalesced layer, while N‐polar AlN grew primarily three‐dimensionally, leading to a columnar structure. This difference in the growth mode led to different properties of domains with opposite polarity, including strain and defect incorporation, as observed by X‐ray diffraction, photoluminescence, and Raman spectroscopy measurements. Finally, an outlook on the applicability and future development of AlN‐based LPS is given. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)