Ultralow-threshold field emission from oriented nanostructured GaN films on Si substrate

Abstract

A series of nanostructured GaN Films have been prepared on Si substrates. Field emission measurements show that the oriented nanostructured GaN film with a thickness of 40 nm has an ultralow threshold field of 1.2 V / m at 1 mA/ cm 2 and yields a stable emission current of 40 mA/ cm 2 at 2.8 V / m, which is comparable to those of carbon nanotubes. A polarization field emission enhancement mechanism with ballistic electron transport is proposed to explain the origin of this ultralow-threshold field emission phenomenon.

Crystallization Effects of Nanocrystalline GaN Films on Field Emission

“…Furthermore, GaN has favorable piezoelectric and spontaneous polarization properties due to the wurtzite crystal structure, which dramatically affects the electrical properties. 11,20−22 By fine-tuning crystallization and orientation, the FE properties of GaN can be dramatically improved, 23,24 but up to now, there has not been a systematic study on the influence of the microstructure on the FE properties of GaN films produced on Si. In this work, a series of nanocrystalline GaN films is prepared on Si by pulsed laser deposition (PLD).…”

“…In the case of diamond-like carbon (DLC), the grain size reduction in the transition from microcrystalline toward nanocrystalline improves the FE properties. , The content of sp 3 carbon atoms is one of the most important factors determining the FE properties of DLC films. − Therefore, electron emission can be enhanced by controlling crystallization during fabrication. Furthermore, GaN has favorable piezoelectric and spontaneous polarization properties due to the wurtzite crystal structure, which dramatically affects the electrical properties. ,− By fine-tuning crystallization and orientation, the FE properties of GaN can be dramatically improved, , but up to now, there has not been a systematic study on the influence of the microstructure on the FE properties of GaN films produced on Si. In this work, a series of nanocrystalline GaN films is prepared on Si by pulsed laser deposition (PLD).…”

Cathodoluminescence and field emission from GaN/MgAl2O4grown by metalorganic chemical vapor deposition: substrate-orientation dependence

“…Therefore, the investigation of the optical and FE properties of GaN with different structures, such as amorphous lms, and low dimensional nanostructures, has been paid more attention recently. [4][5][6][7][8] It is well known that the FE performance strongly depends upon the crystalline quality of the GaN lms. Unfortunately, few substrate materials are currently commercially available for GaN lm growth.…”

Enhanced Field Emission from GaN and AlN Mixed-Phase Nanostructured Film

“…Compared with bulk materials, 1D nanostructures material, such as nanowires and nanotubs, , are relatively unstable and can be easily deformed during operation specially under large current and high power density conditions due to ineffective thermal dissipation. , Therefore, the studies of stable FE thin-film emitters have attracted great attention. To improve FE properties of these film emitters, some ideas have been put forward, such as FE enhancement by an ultrathin wide band gap semiconductor layer, modulating quantum structure of nanofilm − and polarization field of oriented nanostructured films . In addition, the electrical properties of semiconductor materials are closely related to the crystal structure of the samples .…”