Scale-up of the chemical lift-off of (In)GaN-based p-i-n junctions from sapphire substrates using sacrificial ZnO template layers

D. J. Rogers, S. Sundaram, Y. El Gmili, F. Hosseini Teherani, P. Bove, V. Sandana, P. L. Voss, A. Ougazzaden, A. Rajan, K. A. Prior, R. McClintock, M. Razeghi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

(In) GaN p-i-n structures were grown by MOVPE on both GaN-and ZnO-coated c-sapphire substrates. XRD studies of the as-grown layers revealed that a strongly c-axis oriented wurtzite crystal structure was obtained on both templates and that there was a slight compressive strain in the ZnO underlayer which increased after GaN overgrowth. The InGaN peak position gave an estimate of 13.6at% for the indium content in the active layer. SEM and AFM revealed that the top surface morphologies were similar for both substrates, with an RMS roughness (5 mu m x 5 mu m) of about 10 nm. Granularity appeared slightly coarser (40nm for the device grown on ZnO vs 30nm for the device grown on the GaN template) however. CL revealed a weaker GaN near band edge UV emission peak and a stronger broad defect-related visible emission band for the structure grown on the GaN template. Only a strong ZnO NBE UV emission was observed for the sample grown on the ZnO template. Quarter-wafer chemical lift-off (CLO) of the InGaN-based p-i-n structures from the sapphire substrate was achieved by temporary-bonding the GaN surface to rigid glass support with wax and then selectively dissolving the ZnO in 0.1M HCl. XRD studies revealed that the epitaxial nature and strong preferential c-axis orientation of the layers had been maintained after lift-off. This demonstration of CLO scale-up, without compromising the crystallographic integrity of the (In) GaN p-i-n structure opens up the perspective of transferring GaN based devices off of sapphire substrates industrially.

Original languageEnglish
Title of host publicationOxide-based Materials and Devices VI
EditorsFH Teherani, DC Look, DJ Rogers
Place of PublicationBellingham
PublisherSPIE
Number of pages8
DOIs
Publication statusPublished - 2015
EventConference on Oxide-Based Materials and Devices VI - San Francisco, Canada
Duration: 8 Feb 201511 Feb 2015

Publication series

NameProceedings of SPIE
PublisherSPIE
Volume9364
ISSN (Print)0277-786X

Conference

ConferenceConference on Oxide-Based Materials and Devices VI
CountryCanada
Period8/02/1511/02/15

Keywords

  • (In)GaN p-i-n
  • ZnO
  • photovoltaic
  • LED
  • chemical lift-off
  • scale-up
  • substrate
  • GROWTH
  • GAN
  • MOVPE

Cite this