Growth of high resistivity GaN layers by compensating defects generation

Piotr Caban 1Wlodek Strupinski 1Andrzej Turos 1,2Jolanta Borysiuk 1Ewa Dumiszewska 1Karolina Pagowska 2

1. Institute of Electronic Materials Technology (ITME), Wólczyńska 133, Warszawa 01-919, Poland
2. Andrzej Sołtan Institute for Nuclear Studies (IPJ), Świerk, Otwock-Świerk 05-400, Poland


AlGaN/GaN high electron mobility transistors (HEMTs) are one of the most important applications of III-nitride semiconductors in modern microelectronics. They are usually produced in a planar structure on top of a GaN epilayer. High resistivity of GaN layers are prerequisite to obtain good electrical characteristics of HEMTs, especially the pinch-off effect. This can be obtained by compensation of the conductivity of as-grown layers either by defect or chemical mechanism.

In this paper we report on an attempt to obtain the carrier compensation effect in GaN by introducing controlled density of defects. It is well known that high mismatch strain leads to the nucleation of threading dislocations, dislocation loops and other defects that are produced at the substrate-layer interface. In order to be able to control defect distributions the following structure was grown using the MOCVD technique: first the thin AlN nucleation layer was grown on the sapphire substrate followed by the special buffer layer (SBL) of Al0.4Ga0.6N covered with high temperature GaN layer of 1 µm thickness. Since the large part of lattice strain was accommodated by the SBLs the majority of dislocations was grown at the substrate-SBL interface. Consequently, by changing the SBL thickness dislocation propagation into GaN layer can be controlled.

The produced structures were characterized by RBS/channeling and high resolution TEM and XRD techniques, which enabled the judicious choice of the SBL thickness. The ultimate proof was the properly working HEMT device produced on such a high resistivity GaN layer.


Related papers
  1. The influence of pressure on growth of 3C-SiC heteroepitaxial layers on silicon substrates
  2. CVD of graphene on SiC
  3. Modeling of heat and mass transfer in GaN MOVPE reactor
  4. Impact of internal electric fields for GaInN/GaN quantum wells in light emitting diodes
  5. Pinned and unpinned epitaxial and sublimated graphene on SiC
  6. Topographic and reflectometric investigation of 4H silicon carbide epitaxial layer deposited at various growth rates
  7. Synthesis of gallium nitride nanowires by Sublimation Sandwich Method
  8. Raman spectroscopy of single and multilayer graphene on SiC substrates
  9. Study of synthesis and formation mechanisms of nanometric magnesium alumina spinel powders
  10. Growth of GaN layers on silicon and sintered GaN nano-ceramic substrates – TEM investigations
  11. Structure and magnetic properties of carbon encapsulated Fe nanoparticles obtained by arc plasma synthesis
  12. Thick GaN layers on sapphire with various buffer layers
  13. Effects of composition grading at the heterointefaces and Layers Thickness Variations on Bragg Mirror Quality
  14. MOCVD growth and characterization of ultrathin AlN/GaN superlattices on 0001 sapphire substrates
  15. Electrical Properties of GaN/AlGaN Hetrostructures
  16. GaN growth by Sublimation Sandwich Method
  17. Mg diffusion in GaN:Mg grown by metalorganic vapor-phase epitaxy MOVPE
  18. Optical investigations of two dimensional electron gas in the AlGaN/GaN heterostructures
  19. Problems with cracking of AlxGa1-xN layers

Presentation: Poster at Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth, by Piotr Caban
See On-line Journal of Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth

Submitted: 2007-01-15 14:24
Revised:   2009-06-07 00:44