Formation and Applications in Electronic Devices of Lattice‐Aligned Gallium Oxynitride Nanolayer on Gallium Nitride

Abstract

Gallium nitride (GaN), a promising alternative semiconductor to Si, is widely used in photoelectronic and electronic technologies. However, the vulnerability of the GaN surface is a critical restriction that hinders the development of GaN‐based devices, especially in terms of device stability and reliability. In this study, this challenge is overcome by converting the GaN surface into a gallium oxynitride (GaON) epitaxial nanolayer through an in situ two‐step “oxidation–reconfiguration” process. The O plasma treatment overcomes the chemical inertness of the GaN surface, and sequential thermal annealing manipulates the kinetic–thermodynamic reaction pathways to create a metastable GaON nanolayer with a wurtzite lattice. The GaN‐derived GaON nanolayer is a tailored structure for surface reinforcement and possesses several advantages, including a wide bandgap, high thermodynamic stability, and large valence band offset with a GaN substrate. These physical properties can be further leveraged to enhance the performance of GaN‐based devices in various applications, such as power systems, complementary logic integrated circuits, photoelectrochemical water splitting, and ultraviolet photoelectric conversion.

High-Performance Ultraviolet Photodetector Arrays Based on Recessed-Gate HEMT with a Buried p-GaN Layer

“…28 The high-energy oxygen atom bonds with the Ga atom, forming Ga−O bonds and resulting in the formation of GaON with a larger band gap (E g ) than that of GaN, as illustrated in Figure 5b. The energetically favorable and thermodynamic stable bond formation of Ga−O compared to that of Ga−N can be attributed to the lower electron affinity of O than N. 28 Consequently, several O atoms can replace the position of N atoms, while others become interstitial atoms. Analysis of Ga 3d and O 1s core levels in the X-ray photoelectron spectra (XPS) of the GaN sample with OPT is shown in Figure S3.…”

“…The root-mean-square (RMS) values of the AFM images revealed that the ICP etching resulted in a rather rough etching interface, while the OPT improved the surface roughness to a certain extent. The schematic diagram of the formation of the GaON nanolayer by OPT is presented in Figure a . The high-energy oxygen atom bonds with the Ga atom, forming Ga–O bonds and resulting in the formation of GaON with a larger band gap ( E g ) than that of GaN, as illustrated in Figure b.…”

Rapid Response Solar Blind Deep UV Photodetector with High Detectivity Based On Graphene:N/βGa2O3:N/GaN p‐i‐n Heterojunction Fabricated by a Reversed Substitution Growth Method

“…[26] For the oxidation of GaN thin films, Yamada and Chen et al have been demonstrated that the translation from hexagonal GaN to monoclinic 𝛽Ga 2 O 3 in hightemperature oxidation processes with oxygen substituting for nitrogen usually occurred at the penetration dislocation inside GaN films and proposed an oxidation mechanism near the penetration dislocation. [27,28] That is, GaO x generated by high-temperature oxidation migrates through the surface, deposits near the penetration dislocation, and eventually forms massive grains. Since the penetration dislocation density of GaN films is usually about 10 8 cm −2 , the surface roughness of GaO x films formed by hightemperature oxidation is relatively high.…”

Light‐Induced Bipolar Photoresponse with Amplified Photocurrents in an Electrolyte‐Assisted Bipolar p–n Junction

“…[17][18][19] Previous works reveal that the pristine p-GaN/electrolyte interface may suffer large charge-transfer impedance raised by charge trapping from surface states, [20] leading to poor efficiency of the reduction reaction. With the help from co-catalyst loading on surface, the decorated adlayer may act as passivation layer to eliminate the charge-trapping effect, [20][21][22] enabling fast charge transfer from GaN to the adlayer. In addition, such adlayer may also significantly change the reaction activity at nanowire surface by offering plenty of active sites.…”