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A combined growth process for state‐of‐the‐art GaN on silicon
Author(s) -
Gommé Guillaume,
Frayssinet Eric,
Cordier Yvon,
Semond Fabrice
Publication year - 2017
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201600449
Subject(s) - materials science , metalorganic vapour phase epitaxy , sapphire , dislocation , optoelectronics , chemical vapor deposition , layer (electronics) , template , nitride , nanotechnology , epitaxy , composite material , optics , laser , physics
This study aims to simplify the heteroepitaxy of GaN on Si while keeping state‐of‐the‐art III‐nitride materials. The originality of this work is to combine the advantages of both NH 3 ‐MBE and metal organic chemical vapor deposition (MOCVD) growth techniques. First, the structural quality of AlN is assessed by AFM, XRD measurements, and TEM. Terraces and atomic step edges are observed by AFM showing a good structural quality of the AlN epilayer. TEM investigation reveals a sharp and well‐controlled AlN/Si using NH 3 ‐MBE. Then, a 2‐μm thick smooth GaN layers are obtained by MOCVD on top of these AlN templates with the use of a SiN x treatment allowing a 3D growth mode able to induce an efficient dislocation filtering to be obtained. GaN structural properties, measured by XRD, AFM, and SEM, are discussed and compared to GaN‐on sapphire (Al 2 O 3 ). In addition, the stress in the GaN layers grown on these AlN templates with or without a SiN x treatment is assessed. GaN epilayers with a dislocation density in the range of few 10 8 dislocations per cm 2 have been achieved using a single AlN buffer layer (no interlayer) and only 2 μm of GaN.