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Title: On the laser lift-off of lightly doped micrometer-thick n-GaN films from substrates via the absorption of IR radiation in sapphire

Abstract

The intense absorption of CO{sub 2} laser radiation in sapphire is used to separate GaN films from GaN templates on sapphire. Scanning of the sapphire substrate by the laser leads to the thermal dissociation of GaN at the GaN/sapphire interface and to the detachment of GaN films from the sapphire. The threshold density of the laser energy at which n-GaN started to dissociate is 1.6 ± 0.5 J/cm{sup 2}. The mechanical-stress distribution and the surface morphology of GaN films and sapphire substrates before and after laser lift-off are studied by Raman spectroscopy, atomic-force microscopy, and scanning electron microscopy. A vertical Schottky diode with a forward current density of 100 A/cm{sup 2} at a voltage of 2 V and a maximum reverse voltage of 150 V is fabricated on the basis of a 9-μm-thick detached n-GaN film.

Authors:
 [1]; ; ;  [2]; ; ; ; ; ; ; ; ;  [1];  [3];  [1]
  1. Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)
  2. Peter the Great St. Petersburg Polytechnic University (Russian Federation)
  3. Financial University under the Government of the Russian Federation (Russian Federation)
Publication Date:
OSTI Identifier:
22649620
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 51; Journal Issue: 1; Other Information: Copyright (c) 2017 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; ATOMIC FORCE MICROSCOPY; CARBON DIOXIDE LASERS; CURRENT DENSITY; DOPED MATERIALS; GALLIUM NITRIDES; INFRARED RADIATION; INTERFACES; LASER RADIATION; MORPHOLOGY; N-TYPE CONDUCTORS; RAMAN SPECTROSCOPY; SAPPHIRE; SCANNING ELECTRON MICROSCOPY; SCHOTTKY BARRIER DIODES; STRESSES; SUBSTRATES; THIN FILMS

Citation Formats

Voronenkov, V. V., Virko, M. V., Kogotkov, V. S., Leonidov, A. A., Pinchuk, A. V., Zubrilov, A. S., Gorbunov, R. I., Latishev, F. E., Bochkareva, N. I., Lelikov, Y. S., Tarkhin, D. V., Smirnov, A. N., Davydov, V. Y., Sheremet, I. A., and Shreter, Y. G., E-mail: y.shreter@mail.ioffe.ru. On the laser lift-off of lightly doped micrometer-thick n-GaN films from substrates via the absorption of IR radiation in sapphire. United States: N. p., 2017. Web. doi:10.1134/S1063782617010249.
Voronenkov, V. V., Virko, M. V., Kogotkov, V. S., Leonidov, A. A., Pinchuk, A. V., Zubrilov, A. S., Gorbunov, R. I., Latishev, F. E., Bochkareva, N. I., Lelikov, Y. S., Tarkhin, D. V., Smirnov, A. N., Davydov, V. Y., Sheremet, I. A., & Shreter, Y. G., E-mail: y.shreter@mail.ioffe.ru. On the laser lift-off of lightly doped micrometer-thick n-GaN films from substrates via the absorption of IR radiation in sapphire. United States. doi:10.1134/S1063782617010249.
Voronenkov, V. V., Virko, M. V., Kogotkov, V. S., Leonidov, A. A., Pinchuk, A. V., Zubrilov, A. S., Gorbunov, R. I., Latishev, F. E., Bochkareva, N. I., Lelikov, Y. S., Tarkhin, D. V., Smirnov, A. N., Davydov, V. Y., Sheremet, I. A., and Shreter, Y. G., E-mail: y.shreter@mail.ioffe.ru. Sun . "On the laser lift-off of lightly doped micrometer-thick n-GaN films from substrates via the absorption of IR radiation in sapphire". United States. doi:10.1134/S1063782617010249.
@article{osti_22649620,
title = {On the laser lift-off of lightly doped micrometer-thick n-GaN films from substrates via the absorption of IR radiation in sapphire},
author = {Voronenkov, V. V. and Virko, M. V. and Kogotkov, V. S. and Leonidov, A. A. and Pinchuk, A. V. and Zubrilov, A. S. and Gorbunov, R. I. and Latishev, F. E. and Bochkareva, N. I. and Lelikov, Y. S. and Tarkhin, D. V. and Smirnov, A. N. and Davydov, V. Y. and Sheremet, I. A. and Shreter, Y. G., E-mail: y.shreter@mail.ioffe.ru},
abstractNote = {The intense absorption of CO{sub 2} laser radiation in sapphire is used to separate GaN films from GaN templates on sapphire. Scanning of the sapphire substrate by the laser leads to the thermal dissociation of GaN at the GaN/sapphire interface and to the detachment of GaN films from the sapphire. The threshold density of the laser energy at which n-GaN started to dissociate is 1.6 ± 0.5 J/cm{sup 2}. The mechanical-stress distribution and the surface morphology of GaN films and sapphire substrates before and after laser lift-off are studied by Raman spectroscopy, atomic-force microscopy, and scanning electron microscopy. A vertical Schottky diode with a forward current density of 100 A/cm{sup 2} at a voltage of 2 V and a maximum reverse voltage of 150 V is fabricated on the basis of a 9-μm-thick detached n-GaN film.},
doi = {10.1134/S1063782617010249},
journal = {Semiconductors},
number = 1,
volume = 51,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2017},
month = {Sun Jan 15 00:00:00 EST 2017}
}
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