DENG Xu-guang, HAN Jun, XING Yan-hui, WANG Jia-xing, FAN Ya-ming, ZHANG Bao-shun, CHEN Xiang. Growth of Highly Resistive GaN by MOCVD[J]. Chinese Journal of Luminescence, 2013,34(3): 351-355
DENG Xu-guang, HAN Jun, XING Yan-hui, WANG Jia-xing, FAN Ya-ming, ZHANG Bao-shun, CHEN Xiang. Growth of Highly Resistive GaN by MOCVD[J]. Chinese Journal of Luminescence, 2013,34(3): 351-355 DOI: 10.3788/fgxb20133403.0351.
High resistance GaN thin film was grown on sapphire (0001) substrates using metal-organic chemical vapor deposition (MOCVD). Effect of the GaN nucleation layer growth parameters
including reactor pressure
species of carrier gas and growth time
on the electrical characteristics of the following grown GaN buffer was investigated. It is found that GaN films epitaxially grown on the GaN nucleation layers deposited at a relatively lower pressure tend to have a high resistance.High resistance GaN buffer layer can also be prepared by extending growth time of the nucleation layer (
i.e.
increasing the thickness of nucleation layer) or by using N
2
instead of H
2
as carrier gas during the growth of nucleation layer. GaN layers with a sheet resistance as high as 2.4910
11
/□ was obtained. These layers were used as templates for the preparation of epi-wafers with AlGaN/AlN/GaN hetero structures
which were used to fabricate high electron mobility transistors (HEMTs). The highest mobility of these samples reaches to 1 230 cm
2
/(Vs).
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references
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