scholarly journals Uprooting defects to enable high-performance III–V optoelectronic devices on silicon

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Youcef A. Bioud ◽  
Abderraouf Boucherif ◽  
Maksym Myronov ◽  
Ali Soltani ◽  
Gilles Patriarche ◽  
...  
Keyword(s):  
Dislocation Density ◽  
High Performance ◽  
Optoelectronic Devices ◽  
Cost Effective ◽  
Deposition Process ◽  
Scale Production ◽  
Luminescence Efficiency ◽  
Low Dislocation Density ◽  
Mismatched Heteroepitaxy ◽  
Industrial Scale Production

Abstract The monolithic integration of III-V compound semiconductor devices with silicon presents physical and technological challenges, linked to the creation of defects during the deposition process. Herein, a new defect elimination strategy in highly mismatched heteroepitaxy is demonstrated to achieve a ultra-low dislocation density, epi-ready Ge/Si virtual substrate on a wafer scale, using a highly scalable process. Dislocations are eliminated from the epilayer through dislocation-selective electrochemical deep etching followed by thermal annealing, which creates nanovoids that attract dislocations, facilitating their subsequent annihilation. The averaged dislocation density is reduced by over three orders of magnitude, from ~108 cm−2 to a lower-limit of ~104 cm−2 for 1.5 µm thick Ge layer. The optical properties indicate a strong enhancement of luminescence efficiency in GaAs grown on this virtual substrate. Collectively, this work demonstrates the promise for transfer of this technology to industrial-scale production of integrated photonic and optoelectronic devices on Si platforms in a cost-effective way.

scholarly journals III/V-on-Si MQW lasers by using a novel photonic integration method of regrowth on a bonding template

2019 ◽  
Vol 8 (1) ◽  
Author(s):  
Yingtao Hu ◽  
Di Liang ◽  
Kunal Mukherjee ◽  
Youli Li ◽  
Chong Zhang ◽  
...  
Keyword(s):  
Dislocation Density ◽  
High Performance ◽  
Flip Chip ◽  
Continuous Wave ◽  
Integration Method ◽  
Light Emission ◽  
Threshold Current ◽  
Photonic Integration ◽  
Practical Applications ◽  
Low Dislocation Density

Abstract Silicon photonics is becoming a mainstream data-transmission solution for next-generation data centers, high-performance computers, and many emerging applications. The inefficiency of light emission in silicon still requires the integration of a III/V laser chip or optical gain materials onto a silicon substrate. A number of integration approaches, including flip-chip bonding, molecule or polymer wafer bonding, and monolithic III/V epitaxy, have been extensively explored in the past decade. Here, we demonstrate a novel photonic integration method of epitaxial regrowth of III/V on a III/V-on-SOI bonding template to realize heterogeneous lasers on silicon. This method decouples the correlated root causes, i.e., lattice, thermal, and domain mismatches, which are all responsible for a large number of detrimental dislocations in the heteroepitaxy process. The grown multi-quantum well vertical p–i–n diode laser structure shows a significantly low dislocation density of 9.5 × 104 cm−2, two orders of magnitude lower than the state-of-the-art conventional monolithic growth on Si. This low dislocation density would eliminate defect-induced laser lifetime concerns for practical applications. The fabricated lasers show room-temperature pulsed and continuous-wave lasing at 1.31 μm, with a minimal threshold current density of 813 A/cm2. This generic concept can be applied to other material systems to provide higher integration density, more functionalities and lower total cost for photonics as well as microelectronics, MEMS, and many other applications.

scholarly journals Ramalin, a Novel Phenyl Hydrazide from the Lichen Ramalina Terebrata; Isolation, Total Synthesis and Biological Activities

2016 ◽  
Vol 30 (2) ◽  
pp. 35-42
Author(s):  
Durga Prasad Pandey ◽  
Hari Datta Bhattarai
Keyword(s):  
Total Synthesis ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Cost Effective ◽  
Scale Production ◽  
In Vivo Test ◽  
The Antarctic ◽  
Industrial Scale Production

Ramalin, a new L-glutamic acid derivative of phenylhydrazide (Y-glutamyl-N'-(2-hydroxyphenyl) hydrazide, 1) was isolated from the Antarctic lichen, Ramalina terebrata after a series of bioactivity guided fractionation of crude aqueous methanolic extract. Ramalin showed stronger antioxidant activities than commercially available standards, ascorbic acid, trolox, BHA, kojic acid in both, in vitro and in vivo test systems. In addition, ramalin showed no/less toxicity effects against two human cell lines; fibroblast (CCD-986SK) cells and keratinocyte (HaCaT). Thus, realign merits for cosmetic application and industrial scale production were needed. We developed a cost effective total synthesis of ramalin with 71.5% yield and described here.

scholarly journals Towards High Performance Chemical Vapour Deposition V2O5 Cathodes for Batteries Employing Aqueous Media

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5558
Author(s):  
Dimitra Vernardou ◽  
Charalampos Drosos ◽  
Andreas Kafizas ◽  
Martyn E. Pemble ◽  
Emmanouel Koudoumas
Keyword(s):  
Energy Storage ◽  
High Performance ◽  
Large Scale ◽  
Electrode Materials ◽  
Low Cost ◽  
Aqueous Media ◽  
Chemical Vapour ◽  
Cost Effective ◽  
Scale Production ◽  
Environmentally Safe

The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.

scholarly journals Scalable Synthesis of Iron Oxide–Based Composite Films As Freestanding Negative Electrodes With Ultra-High Areal Capacitances For High-Performance Asymmetric Supercapacitors

2021 ◽  
Author(s):  
Jincy Parayangattil Jyothibasu ◽  
Ruei-Hong Wang ◽  
Kenneth Ong ◽  
Juping Hillary Lin Ong ◽  
Rong-Ho Lee
Keyword(s):  
High Performance ◽  
Active Material ◽  
Composite Films ◽  
Negative Electrode ◽  
Cost Effective ◽  
Chemical Precipitation ◽  
Precipitation Process ◽  
Electrochemical Performances ◽  
Scale Production ◽  
Negative Electrodes

Abstract This paper reports a simple, cost-effective, and environmentally friendly procedure for the synthesis of cellulose/functionalized carbon nanotube (f-CNT)/Fe2O3 (CCF) composite films and their performance as freestanding negative electrodes in supercapacitors. A facile chemical precipitation process was performed at room temperature within a short reaction time without requiring any of the special processing conditions used in the conventional hydrothermal synthesis, making it the most cost-efficient method for the bulk-scale production of sustainable supercapacitors. The binder-free negative electrode with ultra-high active material loading exhibited outstanding areal (9107.1 mF cm–2) and volumetric (314 F cm–3) capacitances, which were much greater than the values reported previously in the literature for negative electrodes. Moreover, an asymmetric supercapacitor cell featuring cellulose/f-CNT/MnO2 (CCM) and CCF as its positive and negative electrodes, respectively, achieved superior electrochemical performances. Therefore, on account of the economic and environmental superiority of this method and its bulk scalability, this paper provides a simple, eco-friendly, and cost-effective approach for the development of sustainable supercapacitors for practical use.

scholarly journals Spray Coated Colloidal Quantum Dot Films for Broadband Photodetectors

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1738
Author(s):  
Kaixuan Song ◽  
Jifeng Yuan ◽  
Ting Shen ◽  
Jiuyao Du ◽  
Ruiqi Guo ◽  
...  
Keyword(s):  
Optoelectronic Devices ◽  
Spray Coating ◽  
Adhesive Force ◽  
Active Area ◽  
Scale Production ◽  
Fabrication Technology ◽  
Large Area ◽  
Large Size ◽  
Colloidal Quantum Dot ◽  
Industrial Scale Production

A technique for scalable spray coating of colloidal CdSeTe quantum dots (QDs) for photovoltaics and photodetector applications is presented. A mixture solvent with water and ethanol was introduced to enhance the adhesive force between QDs and the substrate interface. The performance of the detector reached the highest values with 40 spray coating cycles of QD deposition. The photodetectors without bias voltage showed broadband response in the wavelength range of 300–800 nm, and high responsivity of 15 mA/W, detectivity of more than 1011 Jones and rise time of 0.04 s. A large size QD-logo pattern film (10 × 10 cm2) prepared by the spray coating process displayed excellent uniformity of thickness and absorbance. The large area detectors (the active area 1 cm2) showed almost the same performance as the typical laboratory-size ones (the active area 0.1 cm2). Our study demonstrates that the spray coating is a very promising film fabrication technology for the industrial-scale production of optoelectronic devices.

scholarly journals Porous perovskite films integrated with Au–Pt nanowire-based electrodes for highly flexible large-area photodetectors

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Rohit Saraf ◽  
Hua Fan ◽  
Vivek Maheshwari
Keyword(s):  
High Performance ◽  
Mechanical Stability ◽  
Optoelectronic Devices ◽  
Cost Effective ◽  
Ambient Air ◽  
Single Step ◽  
Environmental Stability ◽  
Fast Method ◽  
Large Area ◽  
Research Attention

AbstractFlexible, large-area, and stable perovskite photodetectors have drawn increasing widespread research attention for next-generation wearable and portable optoelectronic devices. However, high mechanical durability coupled with large device area and enhanced environmental stability has not been demonstrated yet to attain practical viability. Herein, a highly bendable, stable, and large-area (3 cm2) flexible polystyrene incorporated perovskite photodetector is presented. Due to the formation of a porous polystyrene-perovskite composite film in a single step it allows unprecedented mechanical stability, maintaining 85% of its original photocurrent value after 10,000 bending cycles at a bending angle of 120°. Equally crucial, the solution-processed self-assembled Pt–Au nanochains were developed to provide a simple and fast method of patterning the conductive and flexible electrodes onto the filter substrate. The optimized polystyrene-perovskite photodetector exhibits a high responsivity up to 2.73 A W−1, a maximum specific detectivity of 6.2 × 1013 Jones, and a superior switching ratio of 1.0 × 104. In addition, the polystyrene-perovskite photodetector yields excellent stability under the combined stresses of moisture, ambient air, and room light, and retains 92% of its original performance for over 30 days. All these results demonstrate that this work provides a facile and cost-effective approach that paves the way to develop high-performance, stable, and highly flexible optoelectronic devices.

scholarly journals Potential challenges and approaches to develop the large area efficient monolithic perovskite solar cells (mPSCs)

2019 ◽  
Vol 30 (23) ◽  
pp. 20320-20329
Author(s):  
Arti Mishra ◽  
Zubair Ahmad
Keyword(s):  
Solar Cells ◽  
Architectural Design ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Cost Effective ◽  
Scale Production ◽  
Large Area ◽  
The Stability ◽  
Future Direction ◽  
Industrial Scale Production

Abstract The next generation technologies based on perovskite solar cells (PSCs) are targeted to develop a true low cost, low tech, widely deployable, easily manufactured and reliable photovoltaics. After the extremely fast evolution in the last few years on the laboratory-scale, PSCs power conversion efficiency (PCE) reached over 24%. However, the widespread use of PSCs requires addressing the stability and industrial scale production issues. Carbon based monolithic perovskite solar cells (mPSCs) are one of the most promising candidates for the commercialization of the PSCs. mPSCs possess a unique architectural design and pave an easy way to produce large area and cost-effective fabrication of the PSCs. In this article, recent progress in the field of mPSCs, challenges and strategies for their improvement are briefly reviewed. Also, we focus on the predominant implementations of recent techniques in the fabrication of the mPSCs to improve their performance. This review is intended to serve as a future direction guide for the scientists who are looking forward to developing more reliable, cost-effective and large area PSCs.

scholarly journals SMA-Assisted Exfoliation of Graphite by Microfluidization for Efficient and Large-Scale Production of High-Quality Graphene

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1653 ◽  
Author(s):  
Yuzhou Wang ◽  
Xianye Zhang ◽  
Haihui Liu ◽  
Xingxiang Zhang
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Cost Effective ◽  
Scale Production ◽  
Polyamide 66 ◽  
High Quality ◽  
Uniform Size ◽  
Large Scale Production ◽  
Maleic Anhydride Copolymer ◽  
Few Layer Graphene

In this paper, the sodium salt of styrene-maleic anhydride copolymer (SMA) was used as a stabilizer in the process of graphite exfoliation to few-layer graphene using the technique of microfluidization in water. This method is simple, scalable, and cost-effective, and it produces graphene at concentrations as high as 0.522 mg mL−1. The generated high-quality graphene consists of few-layer sheets with a uniform size of less than 1 μm. The obtained graphene was uniformly dispersed and tightly integrated into a polyamide 66 (PA66) matrix to create high-performance multifunctional polymer nanocomposites. The tensile strength and thermal conductivity of 0.3 and 0.5 wt% EG/PA66 composites were found to be ~32.6% and ~28.8% greater than the corresponding values calculated for pure PA66, respectively. This confirms that the new protocol of liquid phase exfoliation of graphite has excellent potential for use in the industrial-scale production of high-quality graphene for numerous applications.

Sign in / Sign up

Export Citation Format

Share Document