Continuation: Obtaining and characterization of gallium nitride single crystals, single crystal layers and nanocrystals

Aim of project
The purpose of these experiments was to obtain and characterize gallium nitride: single crystals (doped with copper or gadolinium), single crystal layers (pure and doped with manganese) and nanocrystals.

Gallium nitride, a particularly important III-V semiconductor with a direct band-gap of 3,46 eV, is an ideal material as an ultraviolet or blue light emitter, photodetector and high temperature/ high power electronic device. As potential building blocks for nanoelectronic, nanooptical and nanomechanical devices, nanocrystals have received considerable attention from scientific communities. Doping of copper or gadolinium in GaN lattice could result in ferromagnetic properties in this material. The compounds were prepared in horizontal quartz reactor. As a source of gallium, metallic gallium or gallium nitride powder were used and as a source of nitrogen gaseous ammonia was used. This study has been undertaken in order to determine the influence of process conditions on growth of gallium nitride single crystals, monolayers and nanocrystals.

Measurements involving SEM, electron microprobe, Raman studies and EXAFS were used to investigate the materials obtained.

Expected results
The results of our experiments are presented below:
Using a simple and inexpensive method, single crystals of Ga1-xCuxN and Ga1-xGdxN were obtained;

The concentration of dopants (Cu or Gd) in GaN lattice was up to 0,2 at.%;

Using a simple and inexpensive method, GaN nanoballs and nanorods were obtained (the obtained nanoballs have received no attention as yet, there are no data concerning this subject in the literature);

Two patents applications;

Results of our experiments were published in scientific
magazines:
Chem. Mat, (IF=4,9),
J. of Crystal Growth, (IF=1,9),
Phys. Rev.B, (IF=3,3);

The method of production gallium nitride powder (intermediate product in synthesis GaN single crystals, single crystal layers and nanocrystals) has been developed; the results have shown good reproducibility.

The results of the project will be used to design tool wear diagnostics system in blanking processes.