title: Vertical InGaN light-emitting diodes with a sapphire-face-up structure.
abstract: Vertical GaN-based light-emitting diodes (LEDs) were fabricated with a Si substrate using the wafer-bonding technique. Lapping and dry-etching processes were performed for thinning the sapphire substrate instead of removing this substrate using the laser lift-off technique and the thinning process associated with the wafer-bonding technique to feature LEDs with a sapphire-face-up structure and vertical conduction property. Compared with conventional lateral GaN/sapphire-based LEDs, GaN/Si-based vertical LEDs exhibit higher light output power and less power degradation at a high driving current, which could be attributed to the fact that vertical LEDs behave in a manner similar to flip-chip GaN/sapphire LEDs with excellent heat conduction. In addition, with an injection current of 350 mA, the output power (or forward voltage) of fabricated vertical LEDs can be enhanced (or reduced) by a magnitude of 60% (or 5%) compared with conventional GaN/sapphire-based LEDs.
authors.affiliation: Department of Photonics, National Cheng Kung University, Tainan City 70101, Taiwan.
authors.forename: Y C
authors.initials: YC
authors.lastname: Yang
authors.forename: Jinn-Kong
authors.initials: JK
authors.lastname: Sheu
authors.forename: Ming-Lun
authors.initials: ML
authors.lastname: Lee
authors.forename: Shang-Ju
authors.initials: SJ
authors.lastname: Tu
authors.forename: Feng-Wen
authors.initials: FW
authors.lastname: Huang
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Lai
authors.forename: Schang  Jing
authors.initials: S
authors.lastname: Hon
authors.forename: Tsun Kai
authors.initials: TK
authors.lastname: Ko
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium / Q000737:chemistry*; D007204:Indium / Q000737:chemistry*; D008029:Lighting / Q000295:instrumentation*; D012666:Semiconductors
chemical_list: D007204:Indium; C473348:gallium nitride; D005708:Gallium; C513701:indium nitride; D000537:Aluminum Oxide