Electrical properties of polycrystalline GaN films functionalized with cysteine and stabilization of GaN nanoparticles in aqueous media

Effect of etching with cysteamine assisted phosphoric acid on gallium nitride surface oxide formation

“…Alternatively, the surface can be etched (via heated KOH [13][14][15] or phosphoric/sulfuric 14,16 acid) or coated with thiols, 17 or other molecules. [18][19][20][21][22][23] The etching and surface functionalization routes provide convenient ways to modify GaN surface properties without the need for intensive doping strategies that predominantly rely on hazardous chemicals. 12,24 Etching adds the ability to alter both the surface morphology as well as composition through the formation of pitting structures, which cannot be accomplished by only chemi-or physisorbing compounds on the surface.…”

Precursor chemistry of metal nitride nanocrystals

“…GaN is being investigated for high frequency and high power transistor design. 147,148 InN is a promising compound for optoelectronic applications due to its low bandgap, small effective mass and efficient electron transport. InN is also considered for low-cost, high-efficiency solar cells, photomasks, laser diodes, sensors, and biological imaging.…”

Extended-Gate FET Biosensor Based on GaN Micropillar Array and Polycrystalline Layer: Application to Hg2+ Detection in Human Urine

“…17−20 Furthermore, GaN exhibits excellent chemical stability for biosensor application, and the maturity of GaN based electronic devices (e.g., transistor, LED, solar cell) ensure the integration of GaNbased biosensor with GaN electronic devices, which would bring out multifunctional chip. 21,22 For EGFET biosensor, compared with the crawling nanowire, vertically grown nanowires (e.g., micropillar array, nanorod array) are independent of each other and can expose more side surfaces, making the nanowire array more sensitive to external charge. 24,25 Currently, GaN micropillar array (GMPA) are mainly applied as fluorescence/electrochemical biosensors, only two reports employed crawling GaN nanowires as extended-gate of EGFET biosensor.…”

“…For EGFET biosensor, extended-gate electrode materials with large surface area and low impedance are beneficial to improve the sensing performance, e.g., detection sensitivity and limit of detection (LOD). − , To our best knowledge, materials of Si, SnO 2 , ITO, ZnO, and Ga 2 O 3 with nanorod structure has been used as extended-gate to enhance the sensing performance. ,,,− However, these materials have poor electrical conductivity and require to combine with conductive materials (e.g., Al layer, FTO, Ag wire layer, or corresponding seed layer), this would complicate the preparation, reduce repeatability and lead to reduced practicality. ,,,− In contrast, GaN material can achieve not only high surface area by growing nanowire or nanowire array structures but also high electrical conductivity by using low temperature MOCVD growth. − Furthermore, GaN exhibits excellent chemical stability for biosensor application, and the maturity of GaN based electronic devices (e.g., transistor, LED, solar cell) ensure the integration of GaN-based biosensor with GaN electronic devices, which would bring out multifunctional chip. , For EGFET biosensor, compared with the crawling nanowire, vertically grown nanowires (e.g., micropillar array, nanorod array) are independent of each other and can expose more side surfaces, making the nanowire array more sensitive to external charge. , Currently, GaN micropillar array (GMPA) are mainly applied as fluorescence/electrochemical biosensors, only two reports employed crawling GaN nanowires as extended-gate of EGFET biosensor. , But in fact, the detection sensitivity is poor even with high surface area, because the impedance of GaN nanowires grown by conventional processes is large. Thus, preparing GMPA with high electrical conductivity can further improve the detection sensitivity and LOD, but this is still a challenge.…”