Growth of ZnO(0001) on GaN(0001)/4H-SiC buffer layers by plasma-assisted hybrid molecular beam epitaxy
Artikel i vetenskaplig tidskrift, 2015

Plasma-assisted molecular beam epitaxy was used to grow ZnO(0001) layers on GaN(0001)/4H-SiC buffer layers deposited in the same growth chamber equipped with both N- and O-plasma sources. The GaN buffer layers were grown immediately before initiating the growth of ZnO. Using a substrate temperature of 445 °C and an O2 flow rate of 2.5 standard cubic centimeters per minute, we obtained ZnO layers with statistically smooth surfaces having a root-mean-square roughness of 0.3 nm and a peak-to-valley distance of 3 nm as revealed by atomic force microscopy. The full-width-at-half-maximum for x-ray rocking curves obtained across the ZnO(0002) and ZnO(10 1¯ 5) reflections was 198 and 948 arcsec, respectively. These values indicated that the mosaicity of the ZnO layer was comparable to the corresponding values of the underlying GaN buffer layer. Reciprocal space maps showed that the in-plane relaxation of the GaN and ZnO layers was 82% and 73%, respectively, and that the relaxation occurred abruptly during the growth. Roomerature Hall-effect measurements revealed that the layers were inherently n-type and had an electron concentration of 1×1019 cm-3 and a Hall mobility of 51 cm2/V s.

Gallium nitride

Oxides

Molecular beam epitaxy

Single crystal growth

Zinc oxide

Nitrides

Författare

David Adolph

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Tobias Tingberg

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Tommy Ive

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Journal of Crystal Growth

0022-0248 (ISSN)

Vol. 426 129-134

Ämneskategorier

Fusion, plasma och rymdfysik

DOI

10.1016/j.jcrysgro.2015.05.026

Mer information

Skapat

2017-10-08