Electrodeposited CuSCN metal-semiconductor-metal high performance deep-ultraviolet photodetector

Abstract

This study reports a low-cost electrodeposited copper(I) thiocyanate (CuSCN) film as a wide band-gap absorber layer for deep-ultraviolet (DUV) photodetector (PD) applications. Electrodeposited CuSCN films deposited with electrolyte concentrations of 24 mM and 33 mM were evaluated as the absorber layers for planar metal-semiconductor-metal PDs. The best photo-responsivity of the CuSCN PD was found to be as high as 70.3 A/W at a −1 V bias under DUV illumination at 300 nm, which corresponded to an external quantum efficiency of 3.1 × 104%. Furthermore, the DUV-to-visible rejection ratio (R300 nm/R400 nm) of ∼103 was realized. This study demonstrated that the CuSCN film has great potential for low-cost DUV PD applications.

Ultrasensitive, Superhigh Signal-to-Noise Ratio, Self-Powered Solar-Blind Photodetector Based on n-Ga2O3/p-CuSCN Core–Shell Microwire Heterojunction

“…The rise time (τ r1 ) and decay time (τ d1 ) of the Ga 2 O 3 /CuSCN heterojunction photodetector are counted to be 0.19 and 0.16 s, respectively, which are faster than those of both CuSCN and Ga 2 O 3 devices, indicating that the construction of the n -Ga 2 O 3 / p -CuSCN heterojunction can effectively promote the response speed. Compared with recent reports on electrodeposited CuSCN and exfoliated Ga 2 O 3 UV photodetectors, , the response times of our single device are also outstanding (see Table S1 in the Supporting Information).…”

“…Based on the advancement of peculiar geometry and built-in electric field, the p – n microstructure junction would bring great opportunity for Ga 2 O 3 -based heterojunction photodetectors in weak light signal detection. p -type semiconductor materials, the alternative components in p – n junctions, show an irreplaceable role in constructing high-performance photoelectric devices. ,, As one of the best candidates for p -type semiconductor materials, copper­(I) thiocyanate (CuSCN), whose hole mobility is between 0.01 and 0.1 cm 2 V –1 S –1 and p -type character is attributed to copper vacancies, with a wide direct band gap of 3.9 eV and appropriate electronic levels that allow efficient hole injection/extraction, has successfully been employed as a universal material in the range of thin-film transistors, light-emitting diodes, solar cells, and photodetectors. − Additionally, CuSCN is chemically stable and has low-temperature solution-processed versatility that make it compatible with multiple ancillary material types and large-area manufacturing techniques. , …”

Cl2-Doped CuSCN Hole Transport Layer for Organic and Perovskite Solar Cells with Improved Stability

“…Its high optical transparency suppresses any parasitic absorption of the light generated from the active layer. − In organic and perovskite solar cells (OSCs and PSCs), the CuSCN layer allows the extraction of holes from the photoactive layer, again suppressing any parasitic absorption and allowing the incident radiation of all wavelengths to reach the photoactive layer. − Theoretical studies have linked the advantages of CuSCN as an HTL to its usual lack of any deep carrier trap states and its minimal valence band offset with the archetypal perovskite CH 3 NH 3 PbI 3 . In ultraviolet-based photodetectors (UVPDs), the wide bandgap of CuSCN allows unhindered high absorption in the UV region and could form not only metal–semiconductor–metal (MSM) UVPDs but also p-n junction UVPDs when combined with n -type material. − Finally, CuSCN is one of the few materials for p -channel thin film transistor (TFT) fabrication due to its hole transport selectivity. − …”

Ultraviolet Sensing in WBG: SiC

“…The biasing of the two diodes will always result in reverse operation of one diode while the other is in forward bias enabling the conduction of the current. As was discussed in the previous text for the photoconductor, the device is simple to fabricate, but has additional advantages such as low dark current, low junction capacitance, high bandwidth (BW) and is CMOS compatible [13,15,16].…”