Ultrahigh electrical conductivity in solution-sheared polymeric transparent films

With consumer electronics transitioning toward flexible products, there is a growing need for high-performance, mechanically robust, and inexpensive transparent conductors (TCs) for optoelectronic device integration. Herein, we report the scalable fabrication of highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films via solution shearing. Specific control over deposition conditions allows for tunable phase separation and preferential PEDOT backbone alignment, resulting in record-high electrical conductivities of 4,600 ± 100 S/cm while maintaining high optical transparency. High-performance solution-sheared TC PEDOT:PSS films were used as patterned electrodes in capacitive touch sensors and organic photovoltaics to demonstrate practical viability in optoelectronic applications.

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Lateral PbS Photovoltaic Devices for High Performance Infrared and Terahertz Photodetectors

Nanomaterials ◽

10.3390/nano11071692 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1692

Author(s):

Emmanuel K. Ampadu ◽

Jungdong Kim ◽

Eunsoon Oh

Keyword(s):

High Performance ◽

Room Temperature ◽

Photovoltaic Device ◽

Photovoltaic Devices ◽

Temperature Spectrum ◽

Terahertz Region ◽

Room Temperature Spectrum ◽

Ftir Spectrometer ◽

Titanium Substrates ◽

Deposition Conditions

We fabricated a lateral photovoltaic device for use as infrared to terahertz (THz) detectors by chemically depositing PbS films on titanium substrates. We discussed the material properties of PbS films grown on glass with varying deposition conditions. PbS was deposited on Ti substrates and by taking advantage of the Ti/PbS Schottky junction, we discussed the photocurrent transients as well as the room temperature spectrum response measured by Fourier transform infrared (FTIR) spectrometer. Our photovoltaic PbS device operates at room temperature for wavelength ranges up to 50 µm, which is in the terahertz region, making the device highly applicable in many fields.

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Pocket MUSE: an affordable, versatile and high-performance fluorescence microscope using a smartphone

Communications Biology ◽

10.1038/s42003-021-01860-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yehe Liu ◽

Andrew M. Rollins ◽

Richard M. Levenson ◽

Farzad Fereidouni ◽

Michael W. Jenkins

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

Consumer Electronics ◽

Practical Implementation ◽

The Novel ◽

Point Of Care Diagnostics ◽

Optical Module ◽

Optical Configuration ◽

User Friendly

AbstractSmartphone microscopes can be useful tools for a broad range of imaging applications. This manuscript demonstrates the first practical implementation of Microscopy with Ultraviolet Surface Excitation (MUSE) in a compact smartphone microscope called Pocket MUSE, resulting in a remarkably effective design. Fabricated with parts from consumer electronics that are readily available at low cost, the small optical module attaches directly over the rear lens in a smartphone. It enables high-quality multichannel fluorescence microscopy with submicron resolution over a 10× equivalent field of view. In addition to the novel optical configuration, Pocket MUSE is compatible with a series of simple, portable, and user-friendly sample preparation strategies that can be directly implemented for various microscopy applications for point-of-care diagnostics, at-home health monitoring, plant biology, STEM education, environmental studies, etc.

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2D MoS2 Encapsulated Silicon Nanopillar Array with High-Performance Light Trapping Obtained by Direct CVD Process

Crystals ◽

10.3390/cryst11030267 ◽

2021 ◽

Vol 11 (3) ◽

pp. 267

Author(s):

Minyu Bai ◽

Zhuoman Wang ◽

Jijie Zhao ◽

Shuai Wen ◽

Peiru Zhang ◽

...

Keyword(s):

Silicon Substrate ◽

High Performance ◽

Low Cost ◽

Light Trapping ◽

Incident Light ◽

Single Layer ◽

Chemical Vapor ◽

Optoelectronic Device ◽

Planar Silicon ◽

Shortwave Infrared

Weak absorption remains a vital factor that limits the application of two-dimensional (2D) materials due to the atomic thickness of those materials. In this work, a direct chemical vapor deposition (CVD) process was applied to achieve 2D MoS2 encapsulation onto the silicon nanopillar array substrate (NPAS). Single-layer 2D MoS2 monocrystal sheets were obtained, and the percentage of the encapsulated surface of NPAS was up to 80%. The reflection and transmittance of incident light of our 2D MoS2-encapsulated silicon substrate within visible to shortwave infrared were significantly reduced compared with the counterpart planar silicon substrate, leading to effective light trapping in NPAS. The proposed method provides a method of conformal deposition upon NPAS that combines the advantages of both 2D MoS2 and its substrate. Furthermore, the method is feasible and low-cost, providing a promising process for high-performance optoelectronic device development.

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High-Performance Multi-Stream Management for SSDs

Electronics ◽

10.3390/electronics10040486 ◽

2021 ◽

Vol 10 (4) ◽

pp. 486

Author(s):

Yongjae Chun ◽

Kyeore Han ◽

Youpyo Hong

Keyword(s):

Solid State ◽

High Performance ◽

Data Centers ◽

Consumer Electronics ◽

Input Output ◽

Solid State Drives ◽

Stream Management ◽

Group Data ◽

Separate Area

Owing to their advantages over hard disc drives (HDDs), solid-state drives (SSDs) are widely used in many applications, including consumer electronics and data centers. As erase operations are feasible only in block units, modification or deletion of pages cause invalidation of the pages in their corresponding blocks. To reclaim these invalid pages, the valid pages in the block are copied to other blocks, and the block with the invalid pages is initialized, which adversely affects the performance and durability of the SSD. The objective of a multi-stream SSD is to group data by their expected lifetimes and store each group of data in a separate area called a stream to minimize the frequency of wasteful copy-back and initialization operations. In this paper, we propose an algorithm that groups the data based on input/output (I/O) types and rewrite frequency, which show significant improvements over existing multi-stream algorithms not only for performance but also for effectiveness in covering most applications.

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Scalable Fabrication of High-Performance Transparent Conductors Using Graphene Oxide-Stabilized Single-Walled Carbon Nanotube Inks

Nanomaterials ◽

10.3390/nano8040224 ◽

2018 ◽

Vol 8 (4) ◽

pp. 224 ◽

Cited By ~ 7

Author(s):

Linxiang He ◽

Chengzhu Liao ◽

Sie Tjong

Keyword(s):

Graphene Oxide ◽

Carbon Nanotube ◽

High Performance ◽

Transparent Conductors ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon

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Polarization Microscopy and Infrared Microspectroscopy of Integument Coverings of Diapausing Larvae in Two Distantly Related Nonsocial Bees

Microscopy and Microanalysis ◽

10.1017/s1431927618000053 ◽

2018 ◽

Vol 24 (1) ◽

pp. 75-81

Author(s):

Maria Luiza S. Mello ◽

Benedicto de Campos Vidal ◽

Jerome G. Rozen

Keyword(s):

High Performance ◽

Construction Materials ◽

Positive Staining ◽

Polarization Microscopy ◽

Transparent Films ◽

Social Bees ◽

Sudan Black B ◽

Ft Ir ◽

Ir Signature ◽

Arid Desert

AbstractThe larvae of the two distantly related nonsocial bees Ericrocis lata (Apidae) and Hesperapis (Carinapis) rhodocerata (Melittidae), which develop mostly under arid desert areas of North America, and that differ in that they either spin (E. lata) or do not spin (H. rhodocerata) protective cocoons before entering diapause, produce transparent films that cover the larval integument. To understand the nature of these films, their responses to topochemical tests and their characteristics when examined with fluorescence and high-performance polarization microscopy and microspectroscopy were studied. A positive staining by Sudan black B, birefringence of negative sign, and a Fourier transform-infrared (FT-IR) spectrum typical of lipids were detected for the integument covering of both species. The FT-IR signature, particularly, suggests a wax chemical composition for these lipid coverings, resembling the waxes that are used as construction materials in the honey cells produced by social bees. Considering the arid environmental conditions under which these larvae develop, we hypothesize that their covering films may have evolved as protection against water depletion. This hypothesis seems especially appropriate for H. rhodocerata larvae, which are capable of undergoing a long diapause period in the absence of a protective cocoon.

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Polarity switching from p- to n-type in a single thermoelectric donor-acceptor copolymer by p-type doping

10.21203/rs.3.rs-189287/v1 ◽

2021 ◽

Author(s):

Jing Wang ◽

Yizhuo Wang ◽

Qing Li ◽

Zhanchao Li ◽

Liqing Xu ◽

...

Keyword(s):

Conducting Polymer ◽

High Performance ◽

High Current Density ◽

Organic Polymer ◽

Novel Approach ◽

Polarity Switching ◽

Electrical Conductivities ◽

Planar Film ◽

Donor Acceptor ◽

P Type

Abstract The transport mechanism of organic materials is still far away from being well understood and controlled although conducting polymers have been discovered since 1977. It is rare to see conducting polyers possessing high bipolar (p- and n-type) electrical conductivities within a single bulk doped organic polymer without the assistant of gate voltage. Here, we report a novel approach to provide high performance n-type materials by p-type doping. More importantly, the bipolar electrical conductivities of the donor-acceptor conducting polymer are high, resulting high bipolar power factors among the solution-processable ambipolar D-A copolymers. A fully organic p-n junction is created in a planar film, exhibiting a high rectification ratio of 2 x 102 at +5 V with a high current density of 3 A/cm2. Structural and spectroscopic tests have been performed to provide a fundamental understanding of the polarity switching mechanism. The results open the opportunity of making p- and n-type modules with a single conducting polymer for future modern organic electronics.

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Z-Interconnect Technology - A Reliable, Cost Efficient Solution for High Density, High Performance Electronic Packaging

International Symposium on Microelectronics ◽

10.4071/isom-ta55 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 000141-000147 ◽

Cited By ~ 1

Author(s):

John M. Lauffer ◽

Kevin Knadle

Keyword(s):

Electronic Packaging ◽

High Performance ◽

Performance Enhancement ◽

High Density ◽

Consumer Electronics ◽

Electrical Performance ◽

Printed Wiring Board ◽

Electrically Conductive Adhesive ◽

Plated Through Hole ◽

Interconnect Technology

Common themes across all segments of electronic packaging today are density and performance. High density interconnect (HDI) technology is one of the most commonly utilized methods for electronic package density improvement, while many different areas have been investigated for performance improvement, from low loss dielectric and conductor materials, to via design and via stub reduction. Electrical performance and density requirements are sometimes complementary, but often times, conflicting with one another. This paper will describe the design, materials, fabrication, and reliability of a new Z-Interconnect technology that addresses both high density and high performance demands simultaneously. Z-Interconnect technology uses an electrically conductive adhesive to electrically interconnect several cores (Full Z) or sub-composites (Sub Z) in a single lamination process. Z-Interconnect technology will be compared and contrasted to other commonly used solutions to the performance and density challenges. HDI or sequential build-up technology is a pervasive solution to the density demands in semiconductor packaging and consumer electronics (e.g. Smart phones), but has not caught hold in HPC or A&D printed wiring board (PWB) applications. One solution for PWB electrical performance enhancement is plated through hole (PTH) stub reduction by “back drilling” the unwanted portion of the PTH. Pb-free reflow and Current Induced Thermal Cycling (CITC) test results of product coupons and specially designed test vehicles, having component pitches down to 0.4mm, will be presented. Z-Interconnect test vehicles have survived 6X Pb-free (260C) reflow cycles, followed by greater than 3000 cycles of 23C–150C CITC cycles. Test vehicle and product coupons also easily survive 10 or more 23C–260C CITC cycles.

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