Interfacial electrostatic interaction-enhanced photomultiplication for ultra-high external quantum efficiency of organic photodiodes

Abstract A photomultiplication-type organic photodiode (PM-OPD), where an electric double layer (EDL) is strategically embedded, is demonstrated with an exceptionally high external quantum efficiency (EQE) of 2,210,000%, responsivity of 11,200 A W− 1, specific detectivity of 2.82 × 1014 Jones, and gain-bandwidth product of 1.92 × 107 Hz as well as high reproducibility. A metal-semiconductor Schottky interface consisting of an EDL enables the stabilization of trapped electron states within the acceptor domains of the photoactive layer by electrostatic interactions, boosting the PM-OPD gain generation. The effects of the EDL on the energetics of trapped electron states are confirmed by numerical simulations based on the drift-diffusion approximation of charge carriers. The feasibility of the fabricated high-EQE PM-OPD is demonstrated via a pixelated prototype image sensor. We believe that this new OPD platform opens up the possibility for the ultra-high-sensitivity organic image sensors, while maintaining the advantageous properties of organics.

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A High Performance UV Photodetector from Thin Film Diamond

MRS Proceedings ◽

10.1557/proc-416-419 ◽

1995 ◽

Vol 416 ◽

Cited By ~ 8

Author(s):

Robert D. Mckeag ◽

Michael D. Whitfield ◽

Simon Sm Chan ◽

Lisa Ys Pang ◽

Richard B. Jackman

Keyword(s):

Thin Film ◽

Visible Light ◽

Quantum Efficiency ◽

Dark Current ◽

External Quantum Efficiency ◽

High Performance ◽

Uv Light ◽

High Sensitivity ◽

Uv Photodetector ◽

Deep Uv

ABSTRACTThin film diamond has been used to fabricate a photodetector which displays high sensitivity to deep UV light, with an external quantum efficiency of greater than one, a dark current of less than 0.1nA and which is near ‘blind’ to visible light.

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Transient Current Behavior of Vertically Integrated Amorphous Silicon Diodes

MRS Proceedings ◽

10.1557/proc-0989-a12-03 ◽

2007 ◽

Vol 989 ◽

Author(s):

Gregory Choong ◽

Nicolas Wyrsch ◽

Christophe Ballif ◽

Rolf Kaufmann ◽

Felix Lustenberger

Keyword(s):

Bias Voltage ◽

High Sensitivity ◽

Transient Behavior ◽

Image Sensor ◽

Image Sensors ◽

Commercial Development ◽

Active Pixel ◽

Constant Bias ◽

Pixel Sensors ◽

A Charge

AbstractMonolithic image sensors based on Thin Film on CMOS (TFC) Technology are becoming more and more attractive as an alternative solution to conventional active pixel sensors (APS). Imager with high sensitivity, high dynamic coupled with low dark current values (10-100 pA/cm2 @ 104 V/cm) have been developed. However, issues such as light-induced degradation and image lag hinder the commercial development of a-Si:H based image sensors. The problem of image lag is caused by residual current due to the release of trapped charges after the switch off of the illumination.In this paper, we present a comprehensive study of the transient behavior of the photocurrent in a-Si:H photodiodes deposited on glass, as well as in corresponding diodes implemented in a TFC image sensor when illumination is switched off or periodically varied. The influence of the pixel architecture for two different cases is also analyzed: One setup reproduces the typical 3 transisor APS pixel architecture behavior, in which the bias voltage of the diode varies with the photogenerated charge while the second setup keeps a constant bias voltage applied to the diode by using a charge integrator.The influence of the light-induced defect creation on the performance of the sensors is also presented and discussed.

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External quantum efficiency versus charge carriers mobility in polythiophene/methanofullerene based planar photodetectors

Journal of Applied Physics ◽

10.1063/1.2756079 ◽

2007 ◽

Vol 102 (2) ◽

pp. 024503 ◽

Cited By ~ 24

Author(s):

M. Caironi ◽

T. Agostinelli ◽

D. Natali ◽

M. Sampietro ◽

R. Cugola ◽

...

Keyword(s):

Quantum Efficiency ◽

External Quantum Efficiency ◽

Charge Carriers

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Several processes participating in a decrease and the droop of external quantum efficiency in green InGaN/GaN MQW structures

Journal of Physics Conference Series ◽

10.1088/1742-6596/2086/1/012104 ◽

2021 ◽

Vol 2086 (1) ◽

pp. 012104

Author(s):

N A Talnishnikh ◽

E I Shabunina ◽

N M Shmidt ◽

A E Ivanov

Keyword(s):

Grain Boundaries ◽

Quantum Efficiency ◽

External Quantum Efficiency ◽

Charge Carriers ◽

Experimental Results ◽

Potential Fluctuations ◽

Ingan Alloy

Abstract The obtained experimental results allow us to clarify the nature of mechanisms related to the presence of cations in disordered InGaN alloy and hetero-interfaces. The capture of charge carriers by cations reduces the external quantum efficiency (EQE) in green MQWs at j < 10 A/cm2. The EQE droop phenomenon caused by smoothed out lateral potential fluctuations occurs at j > 10 A/cm2. At j > 40 A/cm2 the droop associated with interactions between charge carriers and dislocations and grain boundaries takes place.

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Front-Inner Lens for High Sensitivity of CMOS Image Sensors

Sensors ◽

10.3390/s19071536 ◽

2019 ◽

Vol 19 (7) ◽

pp. 1536 ◽

Cited By ~ 2

Author(s):

Godeun Seok ◽

Yunkyung Kim

Keyword(s):

High Resolution ◽

Aspect Ratio ◽

High Sensitivity ◽

Image Sensor ◽

Image Sensors ◽

Optical Simulation ◽

Optical Performance ◽

Pixel Size ◽

Cmos Image Sensors ◽

Pixel Pitch

Due to the continuing improvements in camera technology, a high-resolution CMOS image sensor is required. However, a high-resolution camera requires that the pixel pitch is smaller than 1.0 μm in the limited sensor area. Accordingly, the optical performance of the pixel deteriorates with the aspect ratio. If the pixel depth is shallow, the aspect ratio is enhanced. Also, optical performance can improve if the sensitivity in the long wavelengths is guaranteed. In this current work, we propose a front-inner lens structure that enhances the sensitivity to the small pixel size and the shallow pixel depth. The front-inner lens was located on the front side of the backside illuminated pixel for enhancement of the absorption. The proposed structures in the 1.0 μm pixel pitch were investigated with 3D optical simulation. The pixel depths were 3.0, 2.0, and 1.0 μm. The materials of the front-inner lens were varied, including air and magnesium fluoride (MgF2). For analysis of the sensitivity enhancement, we compared the typical pixel with the suggested pixel and confirmed that the absorption rate of the suggested pixel was improved by a maximum of 7.27%, 10.47%, and 29.28% for 3.0, 2.0, and 1.0 μm pixel depths, respectively.

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Demonstration of ultra-small (0.2%) for mini-displays

Applied Physics Express ◽

10.35848/1882-0786/abd06f ◽

2020 ◽

Vol 14 (1) ◽

pp. 011004

Author(s):

Shubhra S. Pasayat ◽

Chirag Gupta ◽

Matthew S. Wong ◽

Ryan Ley ◽

Michael J. Gordon ◽

...

Keyword(s):

Quantum Efficiency ◽

External Quantum Efficiency

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1/f Noise Modelling and Characterization for CMOS Quanta Image Sensors

Sensors ◽

10.3390/s19245459 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5459

Author(s):

Wei Deng ◽

Eric R. Fossum

Keyword(s):

Analog Circuits ◽

Image Sensor ◽

Image Sensors ◽

Correlated Double Sampling ◽

Cmos Image Sensors ◽

Source Follower ◽

Cmos Analog Circuits ◽

Different Origins ◽

Noise Models ◽

Fitting Model

This work fits the measured in-pixel source-follower noise in a CMOS Quanta Image Sensor (QIS) prototype chip using physics-based 1/f noise models, rather than the widely-used fitting model for analog designers. This paper discusses the different origins of 1/f noise in QIS devices and includes correlated double sampling (CDS). The modelling results based on the Hooge mobility fluctuation, which uses one adjustable parameter, match the experimental measurements, including the variation in noise from room temperature to –70 °C. This work provides useful information for the implementation of QIS in scientific applications and suggests that even lower read noise is attainable by further cooling and may be applicable to other CMOS analog circuits and CMOS image sensors.

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