Facile synthesis ofß-Ga2O3based high-performance electronic devices via direct oxidation of solution-processed transition metal dichalcogenides.

Gallium oxide (Ga2O3) is a promising wide bandgap semiconductor that is viewed as a contender for the next generation of high-power electronics due to its high theoretical breakdown electric field and large Baliga's figure of merit. Here, we report a facile route of synthesizingß-Ga2O3via direct oxidation conversion using solution-processed two-dimensional (2D) GaS semiconducting nanomaterial. Higher order of crystallinity in x-ray diffraction patterns and full surface coverage formation in scanning electron microscopy images after annealing were achieved. A direct and wide bandgap of 5 eV was calculated, and the synthesizedß-Ga2O3was fabricated as thin film transistors (TFT). Theß-Ga2O3TFT fabricated exhibits remarkable electron mobility (1.28 cm2Vs-1) and a good current ratio (Ion/Ioff) of 2.06 × 105. To further boost the electrical performance and solve the structural imperfections resulting from the exfoliation process of the 2D nanoflakes, we also introduced and doped graphene inß-Ga2O3TFT devices, increasing the electrical device mobility by ∼8-fold and thereby promoting percolation pathways for the charge transport. We found that electron mobility and conductivity increase directly with the graphene doping concentration. From these results, it can be proved that theß-Ga2O3networks have excellent carrier transport properties. The facile and convenient synthesis method successfully developed in this paper makes an outstanding contribution to applying 2D oxide materials in different and emerging optoelectronic applications.

Direct formation of InN-codoped p-ZnO/n-GaN heterojunction diode by solgel spin-coating scheme.

In this work p-ZnO/n-GaN heterojunction diodes were directly formed on the Si substrate by a combination of cost-effective solgel spin-coating and thermal annealing treatment. Spin-coated n-ZnO films on InN/GaN/Si wafers were converted to p-type polarity after thermal treatment of proper annealing durations. X-ray diffraction (XRD) analysis reveals that InN-codoped ZnO films have grown as the standard hexagonal wurtzite structure with a preferential orientation in the (002) direction. The intensity of the (002) peak decreases for a further extended annealing duration, indicating the greater incorporation of dopants, also confirmed by x-ray photoelectron spectroscopy and low-temperature photoluminescence. Hall and resistivity measurements validate that our p-type ZnO film has a high carrier concentration of 3.73×10¹7 cm⁻³, a high mobility of 210 cm²/Vs, and a low resistivity of 0.079 Ωcm. As a result, the proposed p-ZnO/n-GaN heterojunction diode displays a well-behaving current rectification of a typical p-n junction, and the measured current versus voltage (I-V) characteristic is hence well described by the modified Shockley equation. The research on the fabrication of p-ZnO/n-GaN heterojunctions shown here generates useful advances in the production of cost-effective ZnO-based optoelectronic devices.