Nano Express

Nanoscale Research Letters

, Volume 5, Issue 6, pp 1051-1056

Open Access This content is freely available online to anyone, anywhere at any time.

A New Method for Lift-off of III-Nitride Semiconductors for Heterogeneous Integration

  • Ke Yan ZangAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Email author 
  • , Davy W. C. CheongAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Email author 
  • , Hong Fei LiuAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR)
  • , Hong LiuAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR)
  • , Jing Hua TengAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR)
  • , Soo Jin ChuaAffiliated withInstitute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR)

Abstract

The release and transfer of GaN epilayers to other substrates is of interest for a variety of applications, including heterogeneous integration of silicon logic devices, III–V power devices and optical devices. We have developed a simple wet chemical etching method to release high-quality epitaxial III-nitride films from their substrates. This method builds on a nanoepitaxial lateral overgrowth (NELO) process that provides III-Nitride films with low dislocation densities. NELO is accomplished using a nanoporous mask layer patterned on GaN substrates. Chemical removal of the SiO2 layer after growth of III-Nitride overlayers causes fracture at the interface between the GaN film and the original GaN substrate, resulting in free-standing GaN films with nanostructured surfaces on one side. These layers can be transferred to other substrates, and the nano-structured surface can be used in photonic devices, or planarized for power devices.

Keywords

Nanorod Lift off III-nitride semiconductor