Surface Processes Limiting the High Rate Deposition of High Electronic Quality a-Si

1991 ◽  
Vol 219 ◽  
Author(s):  
S. Veprek ◽  
O. Anibacher ◽  
M. Riickschloβ

ABSTRACTAmorphous silicon of a high electronic quality with Odatk 10-10, σPh ≈ 1·10-4 (Ωcm)-3 and density of gap states of about 0.3 to 2.1016 eV-1cm-3 is deposited at rates up to 17 Å/sec. The rate limiting steps are identified and their control via the plasma parameters is explained. This allows one to establish the fundamental scaling parameters for large-area high-rate deposition of a-Si. Long term stability of the films in terms of postoxidation and photode-gradation is briefly addressed.

2005 ◽  
Vol 862 ◽  
Author(s):  
Scott J. Jones ◽  
Joachim Doehler ◽  
Tongyu Liu ◽  
David Tsu ◽  
Jeff Steele ◽  
...  

AbstractNew types of transparent conductive oxides with low indices of refraction have been developed for use in optical stacks for the amorphous silicon (a-Si) solar cell and other thin film applications. The alloys are ZnO based with Si and MgF added to reduce the index of the materials through the creation of SiO2 or MgF2, with n=1.3-1.4, or the addition of voids in the materials. Alloys with 12-14% Si or Mg have indices of refraction at λ=800nm between 1.6 and 1.7. These materials are presently being used in optical stacks to enhance light scattering by Al/multi-layer/ZnO back reflectors in a-Si based solar cells to increase light absorption in the semiconductor layers and increase open circuit currents and boost device efficiencies. In contrast to Ag/ZnO back reflectors which have long term stability issues due to electromigration of Ag, these Al based back reflectors should be stable and usable in manufactured PV products. In this manuscript, structural properties for the materials will be reported as well as the performance of solar cell devices made using these new types of materials.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
La Li ◽  
Weijia Liu ◽  
Kai Jiang ◽  
Di Chen ◽  
Fengyu Qu ◽  
...  

AbstractZn-ion hybrid supercapacitors (SCs) are considered as promising energy storage owing to their high energy density compared to traditional SCs. How to realize the miniaturization, patterning, and flexibility of the Zn-ion SCs without affecting the electrochemical performances has special meanings for expanding their applications in wearable integrated electronics. Ti3C2Tx cathode with outstanding conductivity, unique lamellar structure and good mechanical flexibility has been demonstrated tremendous potential in the design of Zn-ion SCs, but achieving long cycling stability and high rate stability is still big challenges. Here, we proposed a facile laser writing approach to fabricate patterned Ti3C2Tx-based Zn-ion micro-supercapacitors (MSCs), followed by the in-situ anneal treatment of the assembled MSCs to improve the long-term stability, which exhibits 80% of the capacitance retention even after 50,000 charge/discharge cycles and superior rate stability. The influence of the cathode thickness on the electrochemical performance of the MSCs is also studied. When the thickness reaches 0.851 µm the maximum areal capacitance of 72.02 mF cm−2 at scan rate of 10 mV s−1, which is 1.77 times higher than that with a thickness of 0.329 µm (35.6 mF cm−2). Moreover, the fabricated Ti3C2Tx based Zn-ion MSCs have excellent flexibility, a digital timer can be driven by the single device even under bending state, a flexible LED displayer of “TiC” logo also can be easily lighted by the MSC arrays under twisting, crimping, and winding conditions, demonstrating the scalable fabrication and application of the fabricated MSCs in portable electronics.


2021 ◽  
Author(s):  
Abhijit Chandra Roy ◽  
Navin Kumar ◽  
Shreyas B S ◽  
Ananya Gupta ◽  
Aloke Kumar ◽  
...  

Abstract Soft artificial skin capable of sensing touch, pressure and bending similar to soft human skin is important in many modern-day applications including socially interactive robotics, modern healthcare, augmented reality, etc. However, most of the research effort on soft artificial skin are confined to the lab-scale demonstration. We have demonstrated how a fundamental understanding of the contact mechanics of soft material and a specially constructed soft optical waveguide let us develop a highly efficient, resilient, and large-area soft artificial skin for futuristic applications. The soft artificial skin capable of detect touch, load and bending shows extreme sensitivity (up to \({150 \text{k}\text{P}\text{a}}^{-1}\)) to touch, and load, which is 750 times higher than earlier work. The soft-a-skin shows excellent long-term stability i.e. it shows consistent performance up to almost a year. In addition, we describe a 3D printing process capable of producing large areas, large numbers yet cost-effective soft artificial skin. We have shown the functioning of the soft-a-skin in various means.


2007 ◽  
Vol 124-126 ◽  
pp. 423-426
Author(s):  
Jae Hong Jeon ◽  
Hee Hwan Choe ◽  
Jong Hyun Seo

In order to improve long term stability of a-Si:H TFT for AM-OLED application a new driving method compensating Vth shift requires a new device structure of which hole injection is enhanced. ITO film was investigated for the hole injection material because it is essential material for display devices and has high work function favorable for hole injection. From I-V characteristics of TFTs with two types of source and drain material, i.e. Cr and ITO, the contact properties were measured and compared. Although electron injection property of ITO was worse than Cr, hole injection property was comparable to that of Cr.


Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 386
Author(s):  
Simone M. P. Meroni ◽  
Carys Worsley ◽  
Dimitrios Raptis ◽  
Trystan M. Watson

Perovskite solar cells (PSCs) have already achieved comparable performance to industrially established silicon technologies. However, high performance and stability must be also be achieved at large area and low cost to be truly commercially viable. The fully printable triple-mesoscopic carbon perovskite solar cell (mCPSC) has demonstrated unprecedented stability and can be produced at low capital cost with inexpensive materials. These devices are inherently scalable, and large-area modules have already been fabricated using low-cost screen printing. As a uniquely stable, scalable and low-cost architecture, mCPSC research has advanced significantly in recent years. This review provides a detailed overview of advancements in the materials and processing of each individual stack layer as well as in-depth coverage of work on perovskite formulations, with the view of highlighting potential areas for future research. Long term stability studies will also be discussed, to emphasise the impressive achievements of mCPSCs for both indoor and outdoor applications.


2018 ◽  
Vol 6 (35) ◽  
pp. 17186-17191 ◽  
Author(s):  
Yi Meng ◽  
Guiqing Lin ◽  
Huimin Ding ◽  
Huaping Liao ◽  
Cheng Wang

By loading 70 wt% sulfur into a pyrene-based COF (Py-COF), we constructed Li–S batteries with high-rate capacity and long-term stability.


2000 ◽  
Vol 609 ◽  
Author(s):  
M. Rojahn ◽  
M.B. Schubert

ABSTRACTWe present a new design of micro-photodiodes for in-vitro tests to electrically stimulate the ganglion cells of chicken and rat retinae upon light exposure of the photodiodes. Based on amorphous silicon, our laterally series connected double-stacked micro-photodiodes provide an open circuit voltage of 2.3 volts. Photolithographic steps as well as etching procedures for patterning the back contact, the amorphous silicon layers and the front contact are described. We analyse current- voltage-measurements performed with direct contact of the metal needles of a micro-positioning system to the device's electrodes. In order to test the performance of an individual micro-photodiode in an electrolyte environment, the stimulation electrode of the device is also contacted with a micro-droplet of buffer solution. Further improvement is needed, mainly addressing the problem of long-term stability of the device in electrolyte environments.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Yang-Fan Xu ◽  
Paul N. Duchesne ◽  
Lu Wang ◽  
Alexandra Tavasoli ◽  
Abdinoor A. Jelle ◽  
...  

Abstract Akin to single-site homogeneous catalysis, a long sought-after goal is to achieve reaction site precision in heterogeneous catalysis for chemical control over patterns of activity, selectivity and stability. Herein, we report on metal phosphides as a class of material capable of realizing these attributes and unlock their potential in solar-driven CO2 hydrogenation. Selected as an archetype, Ni12P5 affords a structure based upon highly dispersed nickel nanoclusters integrated into a phosphorus lattice that harvest light intensely across the entire solar spectral range. Motivated by its panchromatic absorption and unique linearly bonded nickel-carbonyl-dominated reaction route, Ni12P5 is found to be a photothermal catalyst for the reverse water gas shift reaction, offering a CO production rate of 960 ± 12 mmol gcat−1 h−1, near 100% selectivity and long-term stability. Successful extension of this idea to Co2P analogs implies that metal phosphide materials are poised as a universal platform for high-rate and highly selective photothermal CO2 catalysis.


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