Development of solar-blind photodetectors based on Si-implanted β-Ga_2O_3

Abstract

β-Ga(2)O(3) films grown on Al(2)O(3) by a metalorganic chemical vapor deposition technique were used to fabricate a solar-blind photodetector with a planar photoconductor structure. The crystal structure and quality of the β-Ga(2)O(3) films were analyzed using X-ray diffraction and micro-Raman spectroscopy. Si ions were introduced into the β-Ga(2)O(3) thin films by ion implantation method and activated by an annealing process to form an Ohmic contact between the Ti/Au electrode and the β-Ga(2)O(3) film. The electrical conductivity of the β-Ga(2)O(3) films was greatly improved by the implantation and subsequent activation of the Si ions. The photoresponse properties of the photodetectors were investigated by analyzing the current-voltage characteristics and the time-dependent photoresponse curves. The fabricated solar-blind photodetectors exhibited photoresponse to 254 nm wavelength, and blindness to 365 nm light, with a high spectral selectivity.

In Situ Characterization and Modification of β‐Ga2O3 Flakes Using an Ion Micro‐Probe

“…A clear current gain is induced by the irradiation showing that the device acts as a radiation sensor. This proton‐induced current is mainly resultant of an increment of the majority charge carrier concentration (i.e., electrons while holes have a very low mobility in β‐Ga 2 O 3 ) caused by additional free electrons excited by band‐band and band‐defect‐band transitions . The proton‐induced current (which is defined by the difference between the I–V curves obtained with and without irradiation) varies almost linearly with the voltage, independently of the signal of the polarization (Figure b)).…”

“…The three decays, with three different orders of magnitude, suggest that at least three different carrier recombination processes, are involved in the decay of the persistent conductivity. A recent work on photodetectors based on Ga 2 O 3 suggested that the fast component with a decay time of 1.2 s is probably associated to band–band transitions . However, Yamaga et al based on luminescence decay measurements suggest much faster decay times for the self‐trapped exciton (in the microsecond range) and the authors attribute lifetimes longer than 1 s to distant electron–hole pairs with deep electron‐trapped centers.…”

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

“…In comparison, monoclinic Ga 2 O 3 (β-Ga 2 O 3 ) possesses an intrinsic g E of 4.9 eV, corresponding to a wavelength of ~260 nm. Therefore, this PD is suitable for solar-blind detection without the need of any alloying process, making β-Ga 2 O 3 PDs better alternatives that have attracted considerable attention in the past decade [10][11][12][13].…”

Band gap engineering of N-alloyed Ga2O3 thin films

“…It has been demonstrated that Ga 2 O 3 is a promising candidate for solar blind UV photodetector, power devices, and photocatalysis in solar water splitting. [10][11][12][13] As a versatile functional material, Ga 2 O 3 not only has the various device applications by utilizing its intrinsic properties, but also owns the flexibility to form important material systems by alloying with other materials, which have been playing a crucial role in different kinds of device applications. As shown in Fig.…”