TITLE

Electrodeless wet etching of GaN assisted with chopped ultraviolet light

AUTHOR(S)
Hwang, Z.H.; Hwang, J.M.; Hwang, H.L.; Hung, W.H.
PUB. DATE
May 2004
SOURCE
Applied Physics Letters;5/10/2004, Vol. 84 Issue 19, p3759
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Electrodeless photoelectrochemical (PEC) etching of GaN was studied in a K2S2O8/KOH solution irradiated with ultraviolet (UV) light either continuously or periodically. The rate of recombination of electrons and holes at dislocation defects is greater than for crystalline GaN, resulting in a rough etched surface with hexagonal pyramids. The shorter the interval of UV irradiation, the smoother is the etched GaN surface; a chopped UV source thus serves to improve the morphology of the etched surface. A uniform and smooth GaN surface was obtained with a root-mean-square roughness 0.37 nm through electrodeless PEC etching in a solution (KOH 0.01 M, K2S2O8 0.05 M) with a chopper frequency 2500 Hz (i.e., duration of irradiation 0.2 ms).
ACCESSION #
13029170

 

Related Articles

  • GaN-Based High-k Praseodymium Oxide Gate MISFETs with P2S5/(NH4)2SX + UV Interface Treatment Technology. Chao-Wei Lin; Hsien-Chin Chiu // Active & Passive Electronic Components;2012, p1 

    This study examines the praseodymium-oxide- (Pr2O3- passivated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) with high dielectric constant in which the AlGaN Schottky layers are treated with P2S5/(NH4)2SX + ultraviolet (UV) illumination. An electron-beam...

  • Photoadsorption and photodesorption for GaN. Foussekis, M.; Baski, A. A.; Reshchikov, M. A. // Applied Physics Letters;4/20/2009, Vol. 94 Issue 16, p162116 

    The effect of an ambient environment on the surface photovoltage and photoluminescence observed for GaN is studied. In air ambient the upward band bending gradually increases under UV illumination and is explained by the photoinduced chemisorption of surface adsorbates. Specifically, the...

  • GaN metal–semiconductor–metal photodetectors grown on lithium gallate substrates by molecular-beam epitaxy. Seo, S. W.; Lee, K. K.; Kang, Sangbeom; Huang, S.; Doolittle, William A.; Jokerst, N. M.; Brown, A. S. // Applied Physics Letters;8/27/2001, Vol. 79 Issue 9, p1372 

    The growth, fabrication, and characterization of ultraviolet metal–semiconductor–metal (MSM) GaN photodetectors grown on LiGaO[sub 2] by molecular-beam epitaxy are reported herein. GaN/LiGaO[sub 2] material with dislocation densities of approximately 10[sup 8] cm[sup -2] and x-ray...

  • Free-standing, optically pumped, GaN/InGaN microdisk lasers fabricated by photoelectrochemical etching. Haberer, E. D.; Sharma, R.; Meier, C.; Stonas, A. R.; Nakamura, S.; DenBaars, S. P.; Hu, E. L. // Applied Physics Letters;11/29/2004, Vol. 85 Issue 22, p5179 

    GaN-based, mushroom-shaped microdisk lasers were fabricated using band-gap selective photoelectrochemical etching. The optically pumped microdisks had well-defined, distinct modes at excitation powers ranging from about 8 to 16 W/cm2. Modal linewidths of 0.09 nm were reported, which was near the...

  • Effect of laser irradiation on the luminescence of Mg and Si-doped GaN films. Zaldivar, M. Herrera; Fernandez, P. // Journal of Applied Physics;1/15/1999, Vol. 85 Issue 2, p1120 

    Presents information on a study which examined the effect of pulsed ultraviolet laser irradiation on the defect structure and the emission properties of gallium nitride (GaN) epitaxial layers using cathodoluminescence microscopy. Experimental details; Results and discussion; Conclusions.

  • Improved ultraviolet emission from reduced defect gallium nitride homojunctions grown on step-free 4H-SiC mesas. Caldwell, Joshua D.; Mastro, Michael A.; Hobart, Karl D.; Glembocki, Orest J.; Eddy, Charles R.; Bassim, Nabil D.; Holm, R. T.; Henry, Richard L.; Twigg, Mark E.; Kub, Fritz; Neudeck, Phillip G.; Trunek, Andrew J.; Powell, J. Anthony // Applied Physics Letters;6/26/2006, Vol. 88 Issue 26, p263509 

    We previously reported 100-fold reductions in III-N heterofilm threading dislocation density achieved via growth on top of (0001) 4H-SiC mesas completely free of atomic scale steps. This letter compares the electroluminescent (EL) output of GaN pn junctions grown on top of 4H-SiC mesas with and...

  • Light output improvement of InGaN ultraviolet light-emitting diodes by using wet-etched stripe-patterned sapphire substrates. Pan, Chang-Chi; Hsieh, Chi-Hsun; Lin, Chih-Wei; Chyi, Jen-Inn // Journal of Applied Physics;Oct2007, Vol. 102 Issue 8, p084503 

    GaN-based epilayers are grown on wet-etched stripe-patterned sapphire substrates, with stripes along the <11-20>sapphire and <1-100>sapphire directions, for 400 nm ultraviolet light-emitting diodes (LEDs). The effects of the etching depth and stripe orientation on the structural and optical...

  • Deep ultraviolet enhanced wet chemical etching of gallium nitride. Peng, L.-H.; Chuang, C.-W.; Ho, J.-K.; Huang, C.-N.; Chen, C.-Y. // Applied Physics Letters;2/23/1998, Vol. 72 Issue 8 

    We report a study of the ultraviolet (UV) irradiation effects on the wet chemical etching of unintentionally doped n-type gallium nitride (GaN) layers grown on sapphire substrates. When illuminated with a 253.7 nm mercury line source, etching of GaN is found to take place in aqueous phosphorus...

  • Vertical injection thin-film AlGaN/AlGaN multiple-quantum-well deep ultraviolet light-emitting diodes. Zhou, L.; Epler, J. E.; Krames, M. R.; Goetz, W.; Gherasimova, M.; Ren, Z.; Han, J.; Kneissl, M.; Johnson, N. M. // Applied Physics Letters;12/11/2006, Vol. 89 Issue 24, p241113 

    Vertically injected thin-film ultraviolet light-emitting diodes operating at 325 and 280 nm are demonstrated. Low-temperature AlN interlayers allow crack-free growth of AlxGa1-xN with compositions up to x=0.53 on GaN-on-sapphire templates. The GaN layer allows laser-induced separation of the...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics