Room‐Temperature Printing of Ultrathin Quasi‐2D GaN Semiconductor via Liquid Metal Gallium Surface Confined Nitridation Reaction

Abstract

Outstanding wide‐bandgap semiconductor material such as gallium nitride (GaN) has been extensively utilized in power electronics, radiofrequency amplifiers, and harsh environment devices. Due to its quantum confinement effect in enabling desired deep‐ultraviolet emission, excitonic impact, and electronic transport features, 2D or ultrathin quasi‐2D GaN semiconductors have been one of the most remarkable candidates for future growth of microelectronic devices. Here, for the first time, the authors report a large area, wide bandgap, and room‐temperature quasi‐2D GaN synthesis and printing strategy through introducing the plasma medicated liquid metal gallium surface‐confined nitridation reaction mechanism. The developed direct fabrication and compositional process is consistent with various electronics manufacturing approaches and thus opens an easy going way for cost‐effective growth of the third‐generation semiconductor. In particular, the fully printed field‐effect transistors relying on the GaN thus made show p‐type switching with an on/off ratio greater than 105, maximum field‐effect hole mobility of 53 cm2 V−1 s−1, and a small sub‐threshold swing. As demonstrated, the present method allows to produce at room temperature the GaN with thickness spanning from 1 nanometer to nanometers. This basic method can be further extended, generalized, and utilized for making various electronic and photoelectronic devices in the coming time.

Sonochemical CO2 Reduction to Acetamide and Liquid C2+ Oxygenates Using a Liquid Metal Gallium-Based Reductant

“…High-resolution TEM images of the GaOOH sample sonicated in 200 ppm NH 4 OH with CO 2 bubbling (Figure 7) show lattice fringe spacings of 0.227, 0.27, and 0.248 nm attributed to GaOOH (200), Ga 2 O 3 (002), and GaN (101) crystal planes, respectively. 65,71 It should be mentioned that Ga x O y N z materials typically have a lattice fringe spacing of 0.25 nm, similar to GaN. 65,71 This experiment was repeated in the absence of CO 2 bubbling (Figure S9), and similar results were found, indicating that CO 2 does not play a role in the particle formation process but is only involved in the formation of liquid products.…”

“…The N 1s region shows a Ga–N peak at 397.5 eV , with an atomic ratio of 66% at 50 ppm that increased to 87.2% at the highest NH 4 OH concentration, as reported in Table . When the experiment was performed in the absence of CO 2 bubbling, this ratio was consistent at 83.1%.…”

“…This would produce a range of useful liquid products while also forming an interesting solid material with semiconducting properties. The solid product can be removed and dried, which potentially could be implemented in other applications such as electronic devices, , hydrogen sensing, and biomolecule detection . Accordingly, there is room for future study in tuning the process parameters such as CO 2 feed, NH 4 OH concentration, and sonication reaction conditions to either maximize liquid production or tailor it toward Ga nitride and oxynitride production to control purity, morphology, and particle size depending on the desired application.…”

Hybrid Tamm plasmon resonance excitation towards a simple and efficient biomedical detector of NaI solution

“…Good crystalline GaN layers can be prepared by using liquid metal gallium surface-conned nitridation reaction at room temperature. 53 High optical quality CaF 2 layers can be grown easily by using magnetron sputtering at low temperatures (<100 C). 54 The whole multilayer structure is now congured as prism/Ag/ polyimide/(GaN/CaF 2 ) 15 /air.…”

Liquid metal droplet dynamics

“…5,10 Owing to these outstanding physical merits, Ga-based LMs are believed to be alternative materials to realize numerous unconventional functions and have quickly raised widespread concerns of multidisciplinary scientists. Over the past 20 years, Ga-based LMs have been successfully applied in a variety of significant areas, including chip cooling, 11,12 printed electronics, [13][14][15] flexible sensors, 16,17 reconfigurable antennas, [18][19][20] optical switches, 21,22 micro-pump, 23,24 bio-medical technology, [25][26][27] two-dimensional (2D) semiconductors, [28][29][30] quantum devices, 31,32 and three-dimensional (3D) fabrication, [33][34][35] and so forth.…”