High-performance high-temperature solar-blind photodetector based on polycrystalline Ga2O3 film

Annealing temperature controlled crystallization mechanism and properties of gallium oxide film in forming gas atmosphere

“…However, both of them will lead to the shift of all the diffraction peaks of Ga 2 O 3 epitaxial film not only the (−402) diffraction pattern. 25,29,44 Zhou et al 10 reported the phenomenon that the (−402) peak positions were shifted to a large angle direction while the peak positions of (−201) and (−603) were not shifted as the increasing annealing temperature. However, this could be related to the existence of (0006) diffraction peak of α-Ga 2 O 3 located at 38.93 • .…”

“…Recently, with the extensive exploration in power electronic devices and deep‐ultraviolet optoelectronic devices, the study of direct wide‐bandgap semiconductor materials has attracted more and more attention. Gallium oxide (Ga 2 O 3 ), on account of its direct ultra‐wide bandgap (4.5–5.4 eV), high melting point, high dielectric constant, and ultrahigh breakdown field, has been used extensively in many fields, such as gas sensors, 1 high‐power electronic devices, 2,3 photo‐catalyst, 4 transparent conducting oxides, 5 metal‐oxide‐semiconductor field‐effect transistors, 6 solar cells, 5,7 light‐emitting diodes, 8,9 and solar‐blind photodetectors 10–12 …”

“…Gallium oxide (Ga 2 O 3 ), on account of its direct ultra-wide bandgap (4.5-5.4 eV), high melting point, high dielectric constant, and ultrahigh breakdown field, has been used extensively in many fields, such as gas sensors, 1 high-power electronic devices, 2,3 photo-catalyst, 4 transparent conducting oxides, 5 metal-oxide-semiconductor field-effect transistors, 6 solar cells, 5,7 light-emitting diodes, 8,9 and solar-blind photodetectors. [10][11][12] Ga 2 O 3 owns five different crystal phases, and the orthorhombic β-Ga 2 O 3 structure is primarily due to its high thermal and chemical stability compared to its other polymorphs. There have been many epitaxial techniques to grow β-Ga 2 O 3 films such as molecular beam epitaxy, 13 spray pyrolysis, 14 sol-gel methods, 15 electron beam evaporation, 16 vacuum thermal evaporation, 17 radiofrequency (RF) magnetron sputtering, 18 plasma-enhanced atomic layer deposition (PEALD), 19 and pulsed laser deposition (PLD).…”

Recent progress on the effects of impurities and defects on the properties of Ga2O3

“…, Ga–O bond), and the peaks with the highest binding energy around 532 eV were assigned to oxygen vacancy (V O ) in general. 157–167 The as-grown Ga 2 O 3 films were post-annealed in the O 2 and N 2 atmospheres respectively in Lee et al 's research. The O content increased more in the O 2 environment (O/Ga = 1.43) than in the N 2 environment (O/Ga = 1.42).…”

Low-Temperature-Crystallized Ga2O3 Thin Films and Their TFT-Type Solar-Blind Photodetectors

“…The reported devices can roughly be divided into two types: junction and metal–semiconductor–metal (MSM). Junction-type photodetectors usually demonstrated a high responsivity, but their overall performance highly depended on the heterolayer that was coupled with the Ga 2 O 3 layer. ,− In some cases, there were even no description of the rejection ratio and decay time, , and the MSM-type detectors usually possessed a fast response speed due to their two back-to-back Schottky diodes. ,− However, the response ability to optical signals was often low except for few devices using c-Ga 2 O 3 after high-temperature (900 °C) annealing in an N 2 atmosphere . Relatively speaking, our device with a processing temperature of only 500 °C demonstrates a responsivity and a rejection ratio comparable to most of the reported devices.…”