Electrical and Structural Properties of All-Sputtered Al/SiO2/p-GaN MOS Schottky Diode

Abstract

The all-sputtered Al/SiO2/p-GaN metal-oxide-semiconductor (MOS) Schottky diode was fabricated by the cost-effective radio-frequency sputtering technique with a cermet target at 400 °C. Using scanning electron microscope (SEM), the thicknesses of the electrodes, insulator SiO2 layer, and p-GaN were found to be ~250 nm, 70 nm, and 1 µm, respectively. By Hall measurement of a p-Mg-GaN film on an SiO2/Si (100) substrate at room temperature, the hole’s concentration (Np) and carrier mobility (μ) were found to be Np = 4.32 × 1016 cm−3 and μ = 7.52 cm2·V−1·s−1, respectively. The atomic force microscope (AFM) results showed that the surface topography of the p-GaN film had smoother, smaller grains with a root-mean-square (rms) roughness of 3.27 nm. By I–V measurements at room temperature (RT), the electrical properties of the diode had a leakage current of ~4.49 × 10−8 A at −1 V, a breakdown voltage of −6 V, a turn-on voltage of ~2.1 V, and a Schottky barrier height (SBH) of 0.67 eV. By C–V measurement at RT, with a frequency range of 100–1000 KHz, the concentration of the diode’s hole increased from 3.92 × 1016 cm−3 at 100 kHz to 5.36 × 1016 cm−3 at 1 MHz, while the Fermi level decreased slightly from 0.109 to 0.099 eV. The SBH of the diode at RT in the C–V test was higher than in the I–V test because of the induced charges by dielectric layer. In addition, the ideality factor (n) and series resistance (Rs) determined by Cheung’s and Norde’s methods, other parameters for MOS diodes were also calculated by C–V measurement at different frequencies.

Lattice Strain and Defects Analysis in Nanostructured Semiconductor Materials and Devices by High‐Resolution X‐Ray Diffraction: Theoretical and Practical Aspects

“…They are also applied in photo detectors such as photodiodes and light emitting diodes (LED). [143][144][145][146][147] However, regardless the crystal system, the presence of linear and point defects can improve or worsen the physical properties of the material. The presence and influence of structural defects mainly depends on the final design of the solid-state semiconductor devices.…”

Advanced Strategies in Thin Films Engineering by Magnetron Sputtering

“…The electrical and structural properties of sputter-deposited p-Mg-In x Ga 1−x N/n-Si hetero-junction diodes and Al/SiO 2 /p-GaN MOS Schottky diodes are studied by Tuan et al [21,22] Electronic transport properties by means of Hall effect measurements are comprehensively performed. Holes concentration and mobility at room temperature are determined, as well as I-V and C-V measurements at different frequencies.…”

Negative series resistance and photo-response properties of Au/PPY-MWCNTs composite/TiO2/Al2O3/n-Si/Al photodiode

“…Due to the presence of an interfacial oxide layer, boundary states, and series resistance, nanotubes (MWCNTs) composites deposited on the oxide layer on silicon structures differ from those expected for their perfect case [8][9][10][11][12][13]. In the previous year's, the importance of silicon technology, the semiconductor/oxide (Si/SiO 2 ) interfacial boundary, and surface imperfections were extensively discussed [14,15], although, insufficient revisions have examined the G-V-T and C-V-T characteristics to define factors such as border state and series resistance of MOS, MS, and MIS Schottky diodes [16][17][18][19]. Trial results, particularly at room temperature, do not provide comprehensive data about the nature of the barrier formation or conduction mechanisms at the Metal -semiconductors (MS) or Metal-Oxide-semiconductors MOS Schottky diodes [20].…”