Wet nitrogen oxidation technology and its anisotropy influence on VCSELs *Project supported by the National Natural Science Foundation of China (Nos. 61335004, 61675046, 61505003) and the Open Fund of IPOC2017B011 (BUPT). (December 2018)

• Record Type: Journal Article
• Authors: He, Yan; He, Xiaoying; Hu, Shuai; Su, Jiale; Li, Chong; Hu, Anqi; Guo, Xia
• Is Part Of: Journal of semiconductors. Volume 39:Number 12(2018:Dec.)
• Publication Date: 2018-12
• Subjects: wet nitrogen oxidation -- vertical-cavity surface-emitting laser -- oxidation anisotropy; 2550 -- 4320J; Semiconductors -- Periodicals; 621.38152
• DOI: 10.1088/1674-4926/39/12/126001
• Languages: English
• ISSNs: 1674-4926

Abstract

Abstract: Vertical cavity surface emitting lasers (VCSELs) are widely used in optical communications and optical interconnects due to their advantages of low threshold, low power consumption and so on. Wet nitrogen oxidation technology, which utilizes H2 O molecules to oxidize the Al0.98 Ga0.02 As, is used for electrical and optical mode confinement. In this paper, the effects of oxidation time, oxidation temperature and oxidation anisotropy on the oxidation rate are explored and demonstrated. The ratio of oxidation rate on [0–11] to [011] crystal orientation is defined as oxidation anisotropy coefficient, which decreases with the increase of oxidation temperature and oxidation time. In order to analyze the effect of the oxidation anisotropy on the VCSEL performance, an oxide-aperture of the VCSELs with two difference shapes is designed and then fabricated. The static performance of these fabricated VCSELs has been measured, whose threshold current ratio ~ 0.714 is a good agreement with that of the theoretical calculation value ~ 0.785. Our research on wet nitrogen oxidation and its anisotropy serves as an important reference in the batch fabrication of large-area VCSELs.