Influencing factors of GaN growth uniformity through orthogonal test analysis. (5th December 2015)

• Record Type: Journal Article
• Authors: Zhang, Zhi; Fang, Haisheng; Yan, Han; Jiang, Zhimin; Zheng, Jiang; Gan, Zhiyin
• Is Part Of: Applied thermal engineering. Volume 91(2015:Dec.)
• Page Start: 53
• Page End: 61
• Publication Date: 2015-12-05
• Subjects: Gallium nitride -- MOCVD -- Growth uniformity -- Process parameters; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2015.08.007
• Languages: English
• ISSNs: 1359-4311

Abstract

Abstract: Gallium nitride (GaN) is widely used in light-emitting diode (LED) devices due to its wide bandgap and excellently optoelectronic performance. The efficiency and lifetime of LEDs are critically determined by quality of GaN, for example, growth uniformity. Metal-organic chemical vapor deposition (MOCVD) is the most popular technique to grow high-quality GaN epitaxial layers. Growth uniformity is influenced by fluid flow, heat transfer and chemical reactions in the reactor. In this paper, the growth process in a close-coupled showerhead (CCS) MOCVD reactor is investigated based on 3D numerical simulation. Influences of the operating parameters on the growth uniformity are presented. To evaluate the role of the parameters systematically and efficiently on the growth uniformity, orthogonal test method is introduced. The results reveal that the growth rate and uniformity are strongly related to the total gas flow rate, the showerhead height and the inlet gas temperature, but are weakly affected by the isothermal wall temperature, the rotating speed and the susceptor temperature under the ranges of the current study. The optimized combination of the parameters is further proposed as a useful reference for obtaining the LED layers with a balance between the growth rate and the growth uniformity in industry. Highlights: Fluid flow, heat transfer, chemical reactions are calculated for a 3D CCS reactor. The effects of process parameters on growth rate and uniformity are investigated. Orthogonal test method is introduced to analyze the effect of multi-factors. Optimal combinations can be obtained for the best growth rate and uniformity.