Integration of PbS Quantum Dot Photodiodes on Silicon for NIR Imaging

Georgitzikis, Epimitheas; Malinowski, Paweł E.; Li, Yunlong; Maes, Jorick; Hagelsieb, Luis Moreno; Guerrieri, Stefano; Hens, Zeger; Heremans, Paul; Cheyns, David

doi:10.1109/jsen.2019.2933741

Cited by 59 publications

(39 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Infrared nanocrystals (IR NCs) raise great promises for the design of low‐cost IR sensors. [ 1,2 ] This especially includes the demonstration of focal plane arrays [ 3 ] in which the active layer is made of NCs operating in the short‐wave, [ 4 ] extended short‐wave, [ 5,6 ] and mid‐wave IR. [ 7,8 ] Compared with epitaxially‐grown semiconductors, colloidal NCs simplify the coupling to the read‐out circuit [ 9–11 ] (i.e., no hybridization step through indium bumps).…”

Section: Introductionmentioning

confidence: 99%

Complex Optical Index of HgTe Nanocrystal Infrared Thin Films and Its Use for Short Wave Infrared Photodiode Design

Rastogi

Chu

Dang

et al. 2021

Advanced Optical Materials

View full text Add to dashboard Cite

semiconductors, colloidal NCs simplify the coupling to the read-out circuit [9][10][11] (i.e., no hybridization step through indium bumps). Beyond the cost reduction, it also eases pixel pitch reduction, bringing it closer to the diffraction limit, [12,13] from 15 to 5 µm typically.Among potential material candidates, HgTe offers the widest spectral tunability. It can be grown under highly confined forms such as nanoplatelets [14][15][16] with bandedge around 800 nm, or as larger sizes (≫Bohr radius) with NCs absorbing in the THz range. [17,18] Over the recent years, significant progresses have been made on the device performance as their geometries have been improved. Compared to initial poorly ligand-exchanged films deposited on interdigitated electrodes, complex photodiodes, [4,19] and phototransistors presenting a reduced dark current and an enhanced photocarrier dissociation are now proposed. The control of the light-matter coupling is certainly one of the directions that have led to the most recent improvements. Cavities [20,21] and plasmonic resonators [22][23][24] have been introduced to obtain strongly-absorbing thin films. The interest for the light-matter coupling control is not only limited to the material absorption. It also raises interest in light emission [25] and also potentially in lasing regarding the The limited investigation of the optical properties of HgTe nanocrystal (NC) thin films has become a bottleneck for the electromagnetic design of devices.Using broadband ellipsometry, the refractive index (n) and the extinction coefficient (k) are determined for a series of HgTe NC films relevant to infrared sensing applications. Electromagnetic simulations reveal that the n value of HgTe NC thin films can conveniently be approximated by its mean spectral value n = 2.35 ± 0.15. This complex optical index is then used to design a diode with i) a reduced amount of Hg containing material (thin film < 150 nm) and ii) a thickness of the device better-matched with the carrier diffusion length. It is demonstrated that introducing an aluminum grating onto the transparent conductive electrode leads to an enhanced absorption while reinforcing the work-function difference between the two electrodes. Broadband (≈1 µm), non-polarized, and strong absorption up to 100% is designed. This leads to a responsivity of 0.2 A W −1 and a detectivity of 2 × 10 10 Jones for 2 µm cut-off wavelength at room-temperature, while the time response is as short as 110 ns.

show abstract

Section: Introductionmentioning

confidence: 99%

Complex Optical Index of HgTe Nanocrystal Infrared Thin Films and Its Use for Short Wave Infrared Photodiode Design

Rastogi

Chu

Dang

et al. 2021

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…21,22 The maturity of PbS CQDs based diodes also attracted interests beyond solar cell applications: for near IR passive and active imaging. 14,23,24 Current best structure is based on the following stack 25 ITO/ETL/PbS(n)/PbS(p)/HTL/Au, where ITO is tin-doped indium oxide used as transparent conductive layer, which is generally thick to reduce the contact resistance. The electron transport layer (ETL) is generally based on an oxide such as TiO2 or ZnO and contribute significantly to the rectifying behavior of the diode.…”

Section: Introductionmentioning

confidence: 99%

Time-Resolved Photoemission to Unveil Electronic Coupling between Absorbing and Transport Layers in a Quantum Dot-Based Solar Cell

Gréboval

Rastogi

et al. 2020

J. Phys. Chem. C

View full text Add to dashboard Cite

Lead sulfide (PbS) colloidal quantum dots-based photodiodes are remarkable structures obtained via colloidal engineering because of their outstanding optoelectronic performances. They combine surface ligand engineering to design a p-n junction with all solution processability. Here we investigate the PbS diode electronic structure combining static and dynamic photoemissions with transport measurements. We show that the n-type nature of the Icapped PbS CQDs shifts the valence band away from the Fermi level compared to the thiol capped nanocrystals. This change in majority carriers can be probed using time resolved X-ray photoemission spectroscopy (TRXPS). We also prove that the photo-induced binding energy shift depends on the nanoparticle surface chemistry. Finally, we demonstrate the ability of TRXPS to selectively probe the electronic structure of each side of an interface. We explore the PbS/MoO3 interface used as hole extractor in the PbS solar cell, using this method. We demonstrate that the PbS layer photosensitizes the MoO3 layer and that the two layers have a quasi-rigid electrostatic coupling. We identify the band bending occurring on the PbS(EDT)/MoO3 to be a limiting factor for the device performance and suggest strategies to overcome this limitation.

show abstract

“…WIR 图像； SW d detectors [95] : 意图 [91] ； (b) Hg EM 图 [93] ； (e) H ) Current and v D film [93] ight source [96] Vol. 42 实物图 [97] re; (b) Cross-se reveals high l ixel array with sensor [98]…”

Section: 吸收谱，Swir 和mentioning

confidence: 99%

Research Progress of Infrared Colloidal Quantum Dots and Their Photodetectors

唐¹,

赵²,

李³

et al. 2020

View full text Add to dashboard Cite

：Infrared technologies provide tremendous value to our modern-day society, in the fields of remote sensing, imaging, metrology, product inspection, environmental monitoring, and biomedical diagnostics. The demand for the third-generation infrared photodetectors, to enable easy-to-fabricate, low-cost, and tunable infrared active optoelectronic materials, has driven the development of infrared colloidal quantum dots (CQDs). This review introduces the preparation methods of infrared CQDs and development of infrared CQD detectors, and lists the representative research results of CQDs in the field of optoelectronics. Finally, the infrared quantum dot photodetectors are summarized, and several research problems are proposed. The results of this study guide the commercialization of the infrared quantum dot detector.

show abstract

Integration of PbS Quantum Dot Photodiodes on Silicon for NIR Imaging

Cited by 59 publications

References 35 publications

Complex Optical Index of HgTe Nanocrystal Infrared Thin Films and Its Use for Short Wave Infrared Photodiode Design

Complex Optical Index of HgTe Nanocrystal Infrared Thin Films and Its Use for Short Wave Infrared Photodiode Design

Time-Resolved Photoemission to Unveil Electronic Coupling between Absorbing and Transport Layers in a Quantum Dot-Based Solar Cell

Research Progress of Infrared Colloidal Quantum Dots and Their Photodetectors

Contact Info

Product

Resources

About