TY - JOUR
T1 - Freestanding patterned polycrystalline GaN substrate by a straightforward and affordable technique
AU - Zainal, N.
AU - Samsudin, M. E.A.
AU - Taib, Muhamad Ikram Md
AU - Ahmad, M. A.
AU - Ariff, A.
AU - Alwadai, N.
AU - Roqan, I. S.
N1 - Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/12
Y1 - 2018/12
N2 - A new process for producing a freestanding patterned polycrystalline GaN substrate by applying a straightforward and affordable technique is presented here. Such substrate was fabricated by depositing ~ 50 µm thick bulk GaN layer on porous Si/Si substrate by e-beam evaporator with successive ammonia annealing to improve the material quality of the GaN layer. The GaN layer was then separated from the porous Si/Si substrate by immersing in an acidic solution. The surface of the freestanding patterned polycrystalline GaN substrate that was in contact with the porous Si/Si substrate consisted of cubic-like structures, as inherited from the porous Si/Si substrate. Although the cubic-like structures were almost uniformly distributed on the surface, they were formed in various heights due to irregular degree of symmetry of the porous Si/Si substrate. X-ray diffraction results suggested that β-Ga2O3 inclusions are inside the freestanding patterned polycrystalline GaN substrate but not on its surface. This was supported by micro-photoluminecsence (PL) measurement, whereby only the GaN PL signals were observed. Furthermore, Raman spectroscopy revealed a small amount of compressive stress (0.23 GPa), suggesting that the substrate was almost relaxed.
AB - A new process for producing a freestanding patterned polycrystalline GaN substrate by applying a straightforward and affordable technique is presented here. Such substrate was fabricated by depositing ~ 50 µm thick bulk GaN layer on porous Si/Si substrate by e-beam evaporator with successive ammonia annealing to improve the material quality of the GaN layer. The GaN layer was then separated from the porous Si/Si substrate by immersing in an acidic solution. The surface of the freestanding patterned polycrystalline GaN substrate that was in contact with the porous Si/Si substrate consisted of cubic-like structures, as inherited from the porous Si/Si substrate. Although the cubic-like structures were almost uniformly distributed on the surface, they were formed in various heights due to irregular degree of symmetry of the porous Si/Si substrate. X-ray diffraction results suggested that β-Ga2O3 inclusions are inside the freestanding patterned polycrystalline GaN substrate but not on its surface. This was supported by micro-photoluminecsence (PL) measurement, whereby only the GaN PL signals were observed. Furthermore, Raman spectroscopy revealed a small amount of compressive stress (0.23 GPa), suggesting that the substrate was almost relaxed.
UR - http://www.scopus.com/inward/record.url?scp=85050369621&partnerID=8YFLogxK
U2 - 10.1016/j.mssp.2018.07.029
DO - 10.1016/j.mssp.2018.07.029
M3 - Article
AN - SCOPUS:85050369621
SN - 1369-8001
VL - 88
SP - 40
EP - 44
JO - Materials Science in Semiconductor Processing
JF - Materials Science in Semiconductor Processing
ER -