Electronic and Optical Modulation of Pine Tree-like Nanostructures of Gallium Nitride

We present the synthesis and characterization of gallium nitride (GaN) pine tree-like nanostructures (PTLNs) grown by low-pressure chemical vapor deposition. A high yield of PTLNs is densely arranged with each PTLN having a typical length of 15.46 +/- 3.38 mu m. From Raman spectroscopy, we observe an E-2(H) peak at 570 +/- 6 cm(-1) which is the primary characteristic of wurtzite. X-ray and ultraviolet photoemission spectroscopy reveal that the electronic structures of GaN PTLNs indicate an n-type character, while the work function and valence band maximum are determined to be 3.30 +/- 0.05 and 3.85 +/- 0.08 eV, respectively. We confirm the electronic nature of our structure from the current-voltage characteristics exhibiting rectifying behavior. Density functional theory calculations of GaN PTLNs modeled by germanium-doped GaN nanowires are consistent with our experimental findings. To summarize, the energy-band diagram is presented for the future of GaN PTLNs in the optoelectronic and sensing applications.

Automated summary

This study presents the synthesis and characterization of gallium nitride (GaN) pine tree-like nanostructures (PTLNs) grown by low-pressure chemical vapor deposition. Various analysis techniques show that these structures exhibit n-type electronic characteristics, with a determined work function and valence band maximum. The experimental findings are consistent with density functional theory calculations and show potential for optoelectronic and sensing applications in the future.