1
|
Chang S, Jin J, Kyhm J, Park TH, Ahn J, Park SYL, Park SI, Hwang DK, Choi SS, Seong TY, Song JD, Hwang GW. SWIR imaging using PbS QD photodiode array sensors. OPTICS EXPRESS 2022; 30:20659-20665. [PMID: 36224805 DOI: 10.1364/oe.459090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/13/2022] [Indexed: 06/16/2023]
Abstract
We fabricated a 1 × 10 PbS QD photodiode array with multiple stacked QD layers with high-resolution patterning using a customized photolithographic process. The array showed the average responsivity of 5.54 × 10-3 A/W and 1.20 × 10-2 A/W at 0 V and -1 V under 1310- nm short-wavelength infrared (SWIR) illumination. The standard deviation of the pixel responsivity was under 10%, confirming the uniformity of the fabrication process. The response time was 2.2 ± 0.13 ms, and the bandwidth was 159.1 Hz. A prototype 1310-nm SWIR imager demonstrated that the QD photodiode-based SWIR image sensor is a cost-effective and practical alternative for III-V SWIR image sensors.
Collapse
|
2
|
Kim J, Jo C, Kim MG, Park GS, Marks TJ, Facchetti A, Park SK. Vertically Stacked Full Color Quantum Dots Phototransistor Arrays for High-Resolution and Enhanced Color-Selective Imaging. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106215. [PMID: 34632653 DOI: 10.1002/adma.202106215] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/24/2021] [Indexed: 06/13/2023]
Abstract
Color-selective multifunctional and multiplexed photodetectors have attracted considerable interest with the increasing demand for color filter-free optoelectronics which can simultaneously process multispectral signal via minimized system complexity. The low efficiency of color-filter technology and conventional laterally pixelated photodetector array structures often limit opportunities for widespread realization of high-density photodetectors. Here, low-temperature solution-processed vertically stacked full color quantum dot (QD) phototransistor arrays are developed on plastic substrates for high-resolution color-selective photosensor applications. Particularly, the three different-sized/color (RGB) QDs are vertically stacked and pixelated via direct photopatterning using a unique chelating chalcometallate ligand functioning both as solubilizing component and, after photoexposure, a semiconducting cement creating robust, insoluble, and charge-efficient QD layers localized in the a-IGZO transistor region, resulting in efficient wavelength-dependent photo-induced charge transfer. Thus, high-resolution vertically stacked full color QD photodetector arrays are successfully implemented with the density of 5500 devices cm-2 on ultrathin flexible polymeric substrates with highly photosensitive characteristics such as photoresponsivity (1.1 × 104 AW-1 ) and photodetectivity (1.1 × 1018 Jones) as well as wide dynamic ranges (>150 dB).
Collapse
Affiliation(s)
- Jaehyun Kim
- Department of Chemistry and Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - Chanho Jo
- Displays and Devices Research Lab. School of Electrical and Electronics Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Myung-Gil Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Gyeong-Su Park
- Department of Material Science and Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Tobin J Marks
- Department of Chemistry and Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - Antonio Facchetti
- Department of Chemistry and Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
- Flexterra Corporation, 8025 Lamon Avenue, Skokie, IL, 60077, USA
| | - Sung Kyu Park
- Displays and Devices Research Lab. School of Electrical and Electronics Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| |
Collapse
|
3
|
Optical characteristics of type-II hexagonal-shaped GaSb quantum dots on GaAs synthesized using nanowire self-growth mechanism from Ga metal droplet. Sci Rep 2021; 11:7699. [PMID: 33833327 PMCID: PMC8032789 DOI: 10.1038/s41598-021-87321-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/25/2021] [Indexed: 11/16/2022] Open
Abstract
We report the growth mechanism and optical characteristics of type-II band-aligned GaSb quantum dots (QDs) grown on GaAs using a droplet epitaxy-driven nanowire formation mechanism with molecular beam epitaxy. Using transmission electron microscopy and scanning electron microscopy images, we confirmed that the QDs, which comprised zinc-blende crystal structures with hexagonal shapes, were successfully grown through the formation of a nanowire from a Ga droplet, with reduced strain between GaAs and GaSb. Photoluminescence (PL) peaks of GaSb capped by a GaAs layer were observed at 1.11 eV, 1.26 eV, and 1.47 eV, assigned to the QDs, a wetting-like layer (WLL), and bulk GaAs, respectively, at the measurement temperature of 14 K and excitation laser power of 30 mW. The integrated PL intensity of the QDs was significantly stronger than that of the WLL, which indicated well-grown GaSb QDs on GaAs and the generation of an interlayer exciton, as shown in the power- and temperature-dependent PL spectra, respectively. In addition, time-resolved PL data showed that the GaSb QD and GaAs layers formed a self-aligned type-II band alignment; the temperature-dependent PL data exhibited a high equivalent internal quantum efficiency of 15 ± 0.2%.
Collapse
|
4
|
Galstyan V. “Quantum dots: Perspectives in next-generation chemical gas sensors” ‒ A review. Anal Chim Acta 2021; 1152:238192. [DOI: 10.1016/j.aca.2020.12.067] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 10/22/2022]
|
5
|
Kim TY, Park S, Kim BJ, Heo SB, Yu JH, Shin JS, Hong JA, Kim BS, Kim YD, Park Y, Kang SJ. Dual-functional quantum-dots light emitting diodes based on solution processable vanadium oxide hole injection layer. Sci Rep 2021; 11:1700. [PMID: 33462375 PMCID: PMC7814015 DOI: 10.1038/s41598-021-81480-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 01/05/2021] [Indexed: 11/14/2022] Open
Abstract
Dual-functional quantum-dots light emitting diodes (QLEDs) have been fabricated using solution processable vanadium oxide (V2O5) hole injection layer to control the carrier transport behavior. The device shows selectable functionalities of photo-detecting and light-emitting behaviors according to the different operating voltage conditions. The device emitted a bright green light at the wavelength of 536 nm, and with the maximum luminance of 31,668 cd/m2 in a forward bias of 8.6 V. Meanwhile, the device could operate as a photodetector in a reverse bias condition. The device was perfectly turned off in a reverse bias, while an increase of photocurrent was observed during the illumination of 520 nm wavelength light on the device. The interfacial electronic structure of the device prepared with different concentration V2O5 solution was measured in detail using x-ray and ultraviolet photoelectron spectroscopy. Both the highest occupied molecular orbital and the gap state levels were moved closer to the Fermi level, according to increase the concentration of V2O5 solution. The change of gap state position enables to fabricate a dual-functional QLEDs. Therefore, the device could operate both as a photodetector and as a light-emitting diode with different applied bias. The result suggests that QLEDs can be used as a photosensor and as a light-emitting diode for the future display industry.
Collapse
Affiliation(s)
- Tae Yeon Kim
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Sungho Park
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Byung Jun Kim
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Su Been Heo
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Jong Hun Yu
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Jae Seung Shin
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea
| | - Jong-Am Hong
- Department of Physics and Research Institute for Basic Sciences, Kyung Hee University, Seoul, 02447, Korea
| | - Beom-Su Kim
- Department of Physics and Research Institute for Basic Sciences, Kyung Hee University, Seoul, 02447, Korea
| | - Young Duck Kim
- Department of Physics and Research Institute for Basic Sciences, Kyung Hee University, Seoul, 02447, Korea
| | - Yongsup Park
- Department of Physics and Research Institute for Basic Sciences, Kyung Hee University, Seoul, 02447, Korea.
| | - Seong Jun Kang
- Department of Advanced Materials Engineering for Information and Electronics (BK21 four), Kyung Hee University, Yongin, 17104, Korea.
| |
Collapse
|
6
|
Georgitzikis E, Genoe J, Heremans P, Cheyns D. Carrier Mobility, Lifetime, and Diffusion Length in Optically Thin Quantum Dot Semiconductor Films. ACS APPLIED MATERIALS & INTERFACES 2020; 12:30565-30571. [PMID: 32538613 DOI: 10.1021/acsami.0c06781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We propose a method to measure the fundamental parameters that govern diffusion transport in optically thin quantum dot semiconductor films and apply it to quantum dot materials with different ligands. Thin films are excited optically, and the profile of photogenerated carriers is modeled using diffusion-based transport equations and taking into account the optical cavity effects. Correlation with steady-state photoluminescence experiments on different stacks comprising a quenching layer allows the extraction of the carrier diffusion length accurately from the experimental data. In the time domain, the mapping of the transient PL data with the solutions of the time-dependent diffusion equation leads to accurate calculations of the photogenerated carrier mobility. These findings allow the estimation of the speed limitations for diffusion-based transport in QD absorbers.
Collapse
Affiliation(s)
- Epimitheas Georgitzikis
- IMEC VZW, Kapeldreef 75, 3001 Heverlee, Belgium
- ESAT, KU Leuven, Kasteelpark Arenberg 10, 3001 Heverlee, Belgium
| | - Jan Genoe
- IMEC VZW, Kapeldreef 75, 3001 Heverlee, Belgium
- ESAT, KU Leuven, Kasteelpark Arenberg 10, 3001 Heverlee, Belgium
| | - Paul Heremans
- IMEC VZW, Kapeldreef 75, 3001 Heverlee, Belgium
- ESAT, KU Leuven, Kasteelpark Arenberg 10, 3001 Heverlee, Belgium
| | | |
Collapse
|
7
|
Kim J, Kwon SM, Jo C, Heo JS, Kim WB, Jung HS, Kim YH, Kim MG, Park SK. Highly Efficient Photo-Induced Charge Separation Enabled by Metal-Chalcogenide Interfaces in Quantum-Dot/Metal-Oxide Hybrid Phototransistors. ACS APPLIED MATERIALS & INTERFACES 2020; 12:16620-16629. [PMID: 32180407 DOI: 10.1021/acsami.0c01176] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Quantum dot (QD)-based optoelectronics have received great interest for versatile applications because of their excellent photosensitivity, facile solution processability, and the wide range of band gap tunability. In addition, QD-based hybrid devices, which are combined with various high-mobility semiconductors, have been actively researched to enhance the optoelectronic characteristics and maximize the zero-dimensional structural advantages, such as tunable band gap and high light absorption. However, the difficulty of highly efficient charge transfer between QDs and the semiconductors and the lack of systematic analysis for the interfaces have impeded the fidelity of this platform, resulting in complex device architectures and unsatisfactory device performance. Here, we report ultrahigh detective phototransistors with highly efficient photo-induced charge separation using a Sn2S64--capped CdSe QD/amorphous oxide semiconductor (AOS) hybrid structure. The photo-induced electron transfer characteristics at the interface of the two materials were comprehensively investigated with an array of electrochemical and spectroscopic analyses. In particular, photocurrent imaging microscopy revealed that interface engineering in QD/AOS with chelating chalcometallate ligands causes efficient charge transfer, resulting in photovoltaic-dominated responses over the whole channel area. On the other hand, monodentate ligand-incorporated QD/AOS-based devices typically exhibit limited charge transfer with atomic vibration, showing photo-thermoelectric-dominated responses in the drain electrode area.
Collapse
Affiliation(s)
- Jaehyun Kim
- Displays and Devices Research Laboratory School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea
| | - Sung Min Kwon
- Displays and Devices Research Laboratory School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea
| | - Chanho Jo
- Displays and Devices Research Laboratory School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea
| | - Jae-Sang Heo
- Department of Medicine, University of Connecticut School of Medicine, Farmington 06030, Connecticut, United States
| | - Won Bin Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Hyun Suk Jung
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Yong-Hoon Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Myung-Gil Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Sung Kyu Park
- Displays and Devices Research Laboratory School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea
| |
Collapse
|
8
|
Kim BJ, Cho NK, Park S, Jeong S, Jeon D, Kang Y, Kim T, Kim YS, Han IK, Kang SJ. Highly transparent phototransistor based on quantum-dots and ZnO bilayers for optical logic gate operation in visible-light. RSC Adv 2020; 10:16404-16414. [PMID: 35498875 PMCID: PMC9052890 DOI: 10.1039/d0ra01756f] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/08/2020] [Indexed: 01/22/2023] Open
Abstract
Highly transparent optical logic circuits operated with visible light signals are fabricated using phototransistors with a heterostructure comprised of an oxide semiconductor (ZnO) with a wide bandgap and quantum dots (CdSe/ZnS QDs) with a small bandgap. ZnO serves as a highly transparent active channel, while the QDs absorb visible light and generate photoexcited charge carriers. The induced charge carriers can then be injected into the ZnO conduction band from the QD conduction band, which enables current to flow to activate the phototransistor. The photoexcited charge transfer mechanism is investigated using time-resolved photoluminescence spectroscopy, scanning Kelvin probe microscopy, and ultraviolet photoelectron spectroscopy. Measurements show that carriers in the QD conduction band can transfer to the ZnO conduction band under visible light illumination due to a change in the Fermi energy level. Moreover, the barrier for electron injection into the ZnO conduction band from the QD conduction band is low enough to allow photocurrent generation in the QDs/ZnO phototransistor. Highly transparent NOT, NOR, and NAND optical logic circuits are fabricated using the QDs/ZnO heterostructure and transparent indium tin oxide electrodes. This work provides a means of developing highly transparent optical logic circuits that can operate under illumination with low-energy photons such as those found in visible light. The operation of highly transparent optical logic circuits composed of phototransistors with QDs/ZnO heterojunctions are demonstrated. Photoexcited charge transfer mechanism was confirmed for photoinduced carriers transfer at the QDs/ZnO interfaces.![]()
Collapse
Affiliation(s)
- Byung Jun Kim
- Department of Advanced Materials Engineering for Information and Electronics
- Kyung Hee University
- Yongin 17101
- Republic of Korea
| | - Nam-Kwang Cho
- Program in Nano Science and Technology
- Graduate School of Convergence Science and Technology
- Seoul National University
- Seoul 08826
- Republic of Korea
| | - Sungho Park
- Department of Advanced Materials Engineering for Information and Electronics
- Kyung Hee University
- Yongin 17101
- Republic of Korea
| | - Shinyoung Jeong
- Nanophotonics Research Center
- Korea Institute of Science and Technology (KIST)
- Seoul 02792
- Republic of Korea
| | - Dohyeon Jeon
- Department of Physics
- Hankuk University of Foreign Studies
- Yongin 17035
- Republic of Korea
| | - Yebin Kang
- Department of Physics
- Hankuk University of Foreign Studies
- Yongin 17035
- Republic of Korea
| | - Taekyeong Kim
- Department of Physics
- Hankuk University of Foreign Studies
- Yongin 17035
- Republic of Korea
| | - Youn Sang Kim
- Program in Nano Science and Technology
- Graduate School of Convergence Science and Technology
- Seoul National University
- Seoul 08826
- Republic of Korea
| | - Il Ki Han
- Nanophotonics Research Center
- Korea Institute of Science and Technology (KIST)
- Seoul 02792
- Republic of Korea
| | - Seong Jun Kang
- Department of Advanced Materials Engineering for Information and Electronics
- Kyung Hee University
- Yongin 17101
- Republic of Korea
| |
Collapse
|