Suppression of indium-composition fluctuations in InGaN epitaxial layers by periodically-pulsed mixture of N2 and H2 carrier gas

• 来源期刊: 中国物理B（英文版）
• 关键词: InGaN alloys suppression of In-fluctuations periodically-pulsed mixture of nitrogen and hydro-gen
• 年，卷（期）: 2018,（12）
• 页码范围: 576-582
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/12/127805

摘要

Indium-composition fluctuations in InGaN epitaxial layers are suppressed by using periodically-pulsed mixture (PPM) of N2 and H2 carrier gas. Photoluminescence, optical transmission, reciprocal space map and space-resolved cathodolu-minescence are employed to characterize the InGaN epilayers. It is shown that the lateral In-fluctuations mainly occur as hillock-like In-rich regions. Both the number and size of In-rich regions are reduced by introducing the PPM carrier gas. Moreover, the measurements first experimentally demonstrate that the H2 carrier gas has a stronger decomposition effect on the In-rich region. As the duration time of the PPM carrier gas increases, the reduction of In-content in the In-rich region reaches up to 12％, however, only 2％ for the In-homogeneous region. These factors lead to the suppression of In-fluctuations.