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Systematic study of epitaxy growth uniformity in a specific MOCVD reactor
Author(s) -
Fang Haisheng,
Zhang Zhi,
Pan Yaoyu,
Ma Ronghui,
Liu Sheng,
Wang Mengying
Publication year - 2014
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.201400254
Subject(s) - susceptor , metalorganic vapour phase epitaxy , chemical vapor deposition , light emitting diode , gallium nitride , materials science , epitaxy , growth rate , gallium , optoelectronics , volumetric flow rate , chemistry , nanotechnology , layer (electronics) , thermodynamics , metallurgy , geometry , mathematics , physics
Gallium nitride (GaN) is a direct bandgap semiconductor widely used in bright light‐emitting diodes (LEDs). Thin‐film GaN is grown by metal‐organic chemical vapour deposition (MOCVD) technique. Reliability, efficiency and durability of LEDs are influenced critically by the quality of GaN films. In this report, a systematic study has been performed to investigate and optimize the growth process. Fluid flow, heat transfer and chemical reactions are calculated for a specific close‐coupled showerhead (CCS) MOCVD reactor. Influences of reactor dimensions and growth parameters have been examined after introducing the new conceptions of growth uniformity and growth efficiency. It is found that GaN growth rate is mainly affected by the concentration of (CH3)3Ga:NH3 on the susceptor, while growth uniformity is mainly influenced by the recirculating flows above the susceptor caused by natural convection. Effect of gas inlet temperature and the susceptor temperature over the growth rate can be explained by two competing mechanisms. High growth efficiency can be achieved by optimizing the reactor design.