TITLE

Optimization of the surface morphologies and electron mobilities in GaN grown by plasma-assisted molecular beam epitaxy

AUTHOR(S)
Heying, B.; Smorchkova, I.; Poblenz, C.; Elsass, C.; Fini, P.; Den Baars, S.; Baars, S. Den; Mishra, U.; Speck, J. S.; Speck, J.S.
PUB. DATE
October 2000
SOURCE
Applied Physics Letters;10/30/2000, Vol. 77 Issue 18
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The morphology and electrical properties of homoepitaxial GaN layers grown by molecular beam epitaxy at 720 °C were investigated as a function of Ga/N ratio. GaN films grown with low Ga/N ratios (N-stable regime) are semi-insulating and have heavily pitted morphologies. GaN films grown with higher Ga/N ratios (intermediate regime) have fewer pits with areas of atomically flat surface. The room-temperature electron mobilities in samples grown in the intermediate regime are greater than 800 cm2/V s and increase with Ga/N ratio. At the highest Ga/N ratios (Ga-droplet regime), Ga droplets formed on the surface during growth. Although the surface morphology is free of pits and atomically flat for films grown within the Ga-droplet regime, the mobility decreases significantly compared to films grown in the intermediate regime. Room-temperature electron mobilities as high as 1191 cm2/V s were measured in a GaN film grown with the highest Ga/N ratio within the intermediate regime. © 2000 American Institute of Physics.
ACCESSION #
4415280

 

Related Articles

  • Direct experimental observation of the local electronic structure at threading dislocations in metalorganic vapor phase epitaxy grown wurtzite GaN thin films. Xin, Y.; James, E. M.; James, E.M.; Arslan, I.; Sivananthan, S.; Browning, N. D.; Browning, N.D.; Pennycook, S. J.; Pennycook, S.J.; Omnes, F.; Beaumont, B.; Faurie, J-P.; Faurie, J.-P.; Gibart, P. // Applied Physics Letters;1/24/2000, Vol. 76 Issue 4 

    The electronic structure of pure edge threading dislocations in metalorganic vapor phase epitaxy grown wurtzite GaN thin films has been studied directly by atomic resolution Z-contrast imaging and electron energy loss spectroscopy in a scanning transmission electron microscope. Dislocation cores...

  • Hall-effect analysis of GaN films grown by hydride vapor phase epitaxy. Go¨tz, W.; Romano, L. T.; Walker, J.; Johnson, N. M.; Molnar, R. J. // Applied Physics Letters;3/9/1998, Vol. 72 Issue 10 

    Hall-effect measurements were conducted on unintentionally doped n-type GaN films grown on sapphire substrates by hydride vapor phase epitaxy. Film nucleation involved either a GaCl or ZnO pretreatment. Variable temperature Hall-effect measurements reveal a dependence of both the electron...

  • Nanoindentation of epitaxial GaN films. Kucheyev, S. O.; Kucheyev, S.O.; Bradby, J. E.; Bradby, J.E.; Williams, J. S.; Williams, J.S.; Jagadish, C.; Toth, M.; Phillips, M. R.; Phillips, M.R.; Swain, M. V.; Swain, M.V. // Applied Physics Letters;11/20/2000, Vol. 77 Issue 21 

    Wurtzite GaN films grown on sapphire substrates are studied by nanoindentation with a spherical indenter. No systematic dependence of the mechanical properties of GaN epilayers on the film thickness (at least for thicknesses from 1.8 to 4 μm) as well as on doping type is observed. Slip is...

  • Thermally annealed GaN nucleation layers and the device-quality metal organic chemical vapor deposition growth of Si-doped GaN films on (00.1) sapphire. Wickenden, D. K.; Miragliotta, J. A.; Bryden, W. A.; Kistenmacher, T. J. // Journal of Applied Physics;6/1/1994, Vol. 75 Issue 11, p7585 

    Investigates the effect of epitaxial growth temperature on the properties of silicon-doped gallium nitride layers on self-nucleated sapphire. Device-related properties that improved with increasing growth temperature and those that showed a local maximum; Distinction of thin films of the IIIA...

  • Structure of GaN films grown by hydride vapor phase epitaxy. Romano, L.T.; Krusor, B.S. // Applied Physics Letters;10/20/1997, Vol. 71 Issue 16, p2283 

    Examines the structure of gallium nitride (GaN) films grown by hydride vapor phase epitaxy on sapphire substrates. Instruments used for studying the structure of GaN films; Examination of the dislocation densities of sapphire and silicon carbide; Achievement of fast growth rates by hydride...

  • Air-bridged lateral epitaxial overgrowth of GaN thin films. Kidoguchi, Isao; Ishibashi, Akihiko; Sugahara, Gaku; Ban, Yuzaburoh // Applied Physics Letters;6/19/2000, Vol. 76 Issue 25 

    A promising technique of selective lateral epitaxy, namely air-bridged lateral epitaxial overgrowth, is demonstrated in order to reduce the wing tilt as well as the threading dislocation density in GaN thin films. A seed GaN layer was etched to make ridge-stripe along <11¯00>[sub GaN]...

  • Vertical and lateral mobilities in n-(Ga, Mn)N. Kim, Jihyun; Ren, F.; Thaler, G. T.; Frazier, R.; Abernathy, C. R.; Pearton, S. J.; Zavada, J. M.; Wilson, R. G. // Applied Physics Letters;3/10/2003, Vol. 82 Issue 10, p1565 

    Lateral electron mobilities in 0.2-µm-thick n-(Ga, Mn)N films were obtained from Hall measurements, producing values of 116∼ 102 cm²/V s in the temperature range from 298 to 373 K. These values are comparable to, but slightly lower than, electron mobilities in n-GaN of the same...

  • Study of GaN thin layers subjected to high-temperature rapid thermal annealing. Katsavets, N.I.; Laws, G. M.; Harrison, I.; Larkins, E. C.; Benson, T. M.; Cheng, T. S.; Foxon, C. T. // Semiconductors;Oct98, Vol. 32 Issue 10, p1048 

    A detailed study of the effect of rapid thermal annealing in a N[sub 2] or Ar atmosphere on the properties of thin GaN layers grown by molecular-beam epitaxy on sapphire substrates was performed. After rapid thermal annealing, an enhancement of the crystal quality of such films was observed....

  • Carbon-hydrogen complexes in vapor phase epitaxial GaN. Gyu-Chul Yi; Wessels, Bruce W. // Applied Physics Letters;1/20/1997, Vol. 70 Issue 3, p357 

    Investigates carbon-hydrogen complexes in vapor phase epitaxial gallium nitride (GaN) films using Fourier transform infrared spectroscopy. Analysis of infrared absorption peaks in the magnesium (Mg)-doped material; Merger of carbon-hydrogen complexes during growth of Mg-doped GaN films;...

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