Importance of separating contacts from the photosensitive layer in heterojunction phototransistors

AbstractIn cyclic articles previously published we described and analysed self-organized light fibres inside a liquid crystalline (LC) cell contained photosensitive polymer (PP) layer. Such asymmetric LC cell we call a hybrid LC cell. Light fibre arises along a laser beam path directed in plane of an LC cell. It means that a laser beam is parallel to photosensitive layer. We observed the asymmetric LC cell response on an external driving field polarization. Observation has been done for an AC field first. It is the reason we decided to carry out a detailed research for a DC driving field to obtain an LC cell response step by step. The properly prepared LC cell has been built with an isolating layer and garbage ions deletion. We proved by means of a physical model, as well as a numerical simulation that LC asymmetric response strongly depends on junction barriers between PP and LC layers. New parametric model for a junction barrier on PP/LC boundary has been proposed. Such model is very useful because of lack of proper conductivity and charge carriers of band structure data on LC material.

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Influence of Ag@SiO2 with Different Shell Thickness on Photoelectric Properties of Hole-Conductor-Free Perovskite Solar Cells

Nanomaterials ◽

10.3390/nano10122364 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2364

Author(s):

Zhiyuan He ◽

Chi Zhang ◽

Rangwei Meng ◽

Xuanhui Luo ◽

Mengwei Chen ◽

...

Keyword(s):

Solar Cells ◽

Shell Thickness ◽

Perovskite Solar Cells ◽

Current Gain ◽

Core Shell ◽

Counter Electrodes ◽

Shell Nanoparticles ◽

Photoelectric Properties ◽

Photosensitive Layer ◽

Core Shell Nanoparticles

In this paper, Ag@SiO2 core-shell nanoparticles (NPs) with different shell thicknesses were prepared experimentally and introduced into the photosensitive layer of mesoscopic hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes. By combining simulation and experiments, the influences of different shell thickness Ag@SiO2 core-shell nanoparticles on the photoelectric properties of the PSCs were studied. The results show that, when the shell thickness of 0.1 wt% Ag@SiO2 core-shell nanoparticles is 5 nm, power conversion efficiency is improved from 13.13% to 15.25%, achieving a 16% enhancement. Through the measurement of the relevant parameters of the obtained perovskite film, we found that this gain not only comes from the increase in current density that scholars generally think, but also comes from the improvement of the film quality. Like current gain, this gain is related to the different shell thickness of Ag@SiO2 core-shell nanoparticles. Our research provides a new direction for studying the influence mechanism of Ag@SiO2 core-shell nanoparticles in perovskite solar cells.

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Daguerrotype – the first ever practically used photographic technique Daguerrotype – the first ever practically used photographic technique

Koroze a ochrana materialu ◽

10.2478/kom-2014-0009 ◽

2014 ◽

Vol 58 (2) ◽

pp. 59-64

Author(s):

J. Švadlena

Keyword(s):

Electron Microscopy ◽

Production Process ◽

19Th Century ◽

Silver Layer ◽

Mechanical Resistance ◽

Basic Information ◽

Silver Halides ◽

Photographic Technique ◽

Photosensitive Layer ◽

Conservation Interventions

Abstract The study summarises the basic information on daguerreotype, the first ever practically used photographic process, which was used mainly in the period 1840 - 1860. Daguerrotype takes advantage of a photosensitive layer of silver halides on a silver layer to capture an image, it uses a reaction of silver with mercury vapours to develop the image. The production process via daguerreotype as described hasn’t changed since its deployment and stabilisation in the middle of 19th century. The properties of a daguerreotype image are given by its soft microstructure, which could have only been described after introduction of the electron microscopy. The susceptibility of daguerrotypes to damage and degradations stems not only from their low mechanical resistance but also from unsuitable conservation interventions and archiving conditions.

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Dependence of the Spatial Resolution of a Matrix Photodetector Based on Indium Antimonide on the Thickness of the Photosensitive Layer

Journal of Communications Technology and Electronics ◽

10.1134/s1064226921030037 ◽

2021 ◽

Vol 66 (3) ◽

pp. 333-336

Author(s):

K. O. Boltar ◽

P. V. Vlasov ◽

P. S. Lazarev ◽

A. A. Lopukhin ◽

V. F. Chishko

Keyword(s):

Spatial Resolution ◽

Indium Antimonide ◽

Photosensitive Layer

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Photosensitive Layer-by-Layer Assemblies Containing Azobenzene Groups: Synthesis and Biomedical Applications

Polymers ◽

10.3390/polym9110553 ◽

2017 ◽

Vol 9 (11) ◽

pp. 553 ◽

Cited By ~ 10

Author(s):

Uichi Akiba ◽

Daichi Minaki ◽

Jun-ichi Anzai

Keyword(s):

Biomedical Applications ◽

Layer By Layer ◽

Photosensitive Layer ◽

Azobenzene Groups

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Linear HgCdTe IR FPA 288×4 with bidirectional scanning

Opto-Electronics Review ◽

10.2478/s11772-010-1021-z ◽

2010 ◽

Vol 18 (3) ◽

Author(s):

V.V. Vasilyev ◽

A.V. Predein ◽

V.S. Varavin ◽

N.N. Mikhailov ◽

S.A. Dvoretsky ◽

...

Keyword(s):

Integrated Circuits ◽

Bias Voltage ◽

Differential Resistance ◽

Cmos Technology ◽

Inert Atmosphere ◽

Reverse Bias Voltage ◽

Zero Bias ◽

Photosensitive Layer ◽

Boron Ions ◽

Dark Currents

AbstractThe long wavelength (8–12 μm) IR FPA 288×4 based on a hybrid assembly of n+-p diode photosensitive arrays (PA) of HgCdTe (MCT) MBE-grown structures and time delay integration (TDI) readout integrated circuits (ROIC) with bidirectional scanning have been developed, fabricated, and investigated. The p-type MCT structures were obtained by thermal annealing of as-grown n-type material in inert atmosphere. The MCT photosensitive layer with the composition 0.20–0.23 of mole fraction of CdTe was surrounded by the wide gap layers to decrease the recombination rate and surface leakage current. The diode arrays were fabricated by planar implantation of boron ions into p-MCT. The typical dark currents were about 4–7 nA at the reverse bias voltage of 150 mV. The differential resistance R was up to R0 = 1.6×107 Ω zero bias voltage, which corresponded to R0A ∼70 Ω ·cm2 and to the maximal value Rmax = 2.1 × 108 Ω. The bidirectional TDI deselecting ROIC was developed and fabricated by 1.0-μm CMOS technology with two metallic and two polysilicon layers.The IR FPAs were free of defect channels and have the average values of responsivity Sλ = 2.27×108 V/W, the detectivity Dλ * = 2.13 × 1011 cm × Hz1/2 × Wt1, and the noise equivalent temperature difference NETD = 9 mK.

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