Highly sensitive, broad-band organic photomultiplication-type photodetectors covering UV-Vis-NIR

Abstract

Broad-band organic photomultiplication-type photodetectors were successfully fabricated with one photon harvesting layer and one photomultiplication layer, exhibiting broad response range from 300 to 1000 nm and over 50400% EQE at 360 nm.

Wide Bandgap Polymer with Narrow Photon Harvesting in Visible Light Range Enables Efficient Semitransparent Organic Photovoltaics

“…The 1 nm Au layer is used as a seed layer, which is conducive to forming smooth and continuous Ag layer. [45][46][47] The J-V curves of semitransparent OPVs were measured under AM 1.5G simulated solar light with an intensity of 100 mW cm −2 , as shown in Figure 5a. The J SC values of semitransparent OPVs are gradually enhanced with increasing the thickness of Ag layer, which is due to the enhanced photon utilization in active layers.…”

Infrared Organic Photodetectors Employing Ultralow Bandgap Polymer and Non‐Fullerene Acceptors for Biometric Monitoring

“…Many advances in the design of infrared-sensing materials were achieved during the development of bulk heterojunction (BHJ) organic photovoltaics (OPV) to enhance their solar light harvesting and power conversion efficiencies. [17][18][19][20][21] This has greatly impacted the OPD field, as OPDs share certain working principles with OPV, and can benefit from the rapid increase in the available array of low-bandgap materials. [2,22] The main synthetic strategy to lower the bandgap and tune the electronic levels of conjugated polymers for OPV/OPD applications, involves the stabilization of the semiconductors' quinoid resonance form, the use of alternating donor and acceptor units, or a combination of both methods.…”

“…Many advances in the design of infrared‐sensing materials were achieved during the development of bulk heterojunction (BHJ) organic photovoltaics (OPV) to enhance their solar light harvesting and power conversion efficiencies. [ 17–21 ] This has greatly impacted the OPD field, as OPDs share certain working principles with OPV, and can benefit from the rapid increase in the available array of low‐bandgap materials. [ 2,22 ]…”

Strain-durable dark current in near-infrared organic photodetectors for skin-conformal photoplethysmographic sensors

“…Development of high-detectivity near-infrared photodetectors (NIR PDs) have received significant attention in recent years because of their diverse applications including NIR image sensors, thermal detectors, biomedical sensors, and telecommunication devices ( Liu et al., 2021a , 2021b ; Li et al., 2019a ; Meng et al., 2021 ; Chow and Someya, 2020 ). For demonstrating high-performance NIR PDs, various types of low-bandgap inorganic semiconductors absorbing long wavelengths lights, such as Si, GaAs, InSb, HgCdTe, and CdZnTe, have been developed ( Lu et al., 2018 ; Wang et al., 2021 ; Li et al., 2016 ; Shkir et al., 2019 ; Zhang et al., 2020 ).…”

“…This problem becomes worse on the flexible or stretchable substrates which are essential component for wearable electronics in particular for photoplethysmography (PPG) sensors based on NIR OPDs. To suppress degree of J D in NIR OPDs, energy level tailoring for NIR-light-absorbing CPs and SMs has been carried out through organic synthesis ( Lee et al., 2019 ; Simone et al., 2020 ; Kang et al., 2020 ), while designing device architecture has been also tried such as employing charge blocking layers ( Zhou et al., 2015 ; Yang et al., 2021 ) or structural engineering in photomultiplication (PM)-type PDs ( Zhao et al., 2021a ; Liu et al., 2021a , 2021b ). However, development of new materials every time is less competitive due to its complicated procedures, and little amount of charge carriers is still injected ( Guo et al, 2020 ) even with charge blocking layers by tunneling process under high reverse bias.…”