نتایج جستجو برای: chemical passivation

تعداد نتایج: 381255  

Journal: :European journal of orthodontics 2016
Justin Silverstein Osmar Barreto Rodrigo França

OBJECTIVES The goal of this study was to determine the chemical composition of the passivation layer of three clinically available orthodontic miniscrews at different depths. MATERIALS AND METHODS The miniscrews used were Aarhus Mini-Implant (AAR), IMTEC Ortho (IMT), and VectorTAS (VEC). The chemical compositions of the as-received miniscrews were determined by X-ray photoelectron spectroscop...

2001
Jan Schmidt Mark Kerr Andrés Cuevas

Two different techniques for the electronic surface passivation of silicon solar cells, the plasma-enhanced chemical vapour deposition of silicon nitride (SiN) and the fabrication of thin thermal silicon oxide/plasma SiN stack structures, are investigated. It is demonstrated that, despite their low thermal budget, both techniques are capable of giving an outstanding surface passivation quality ...

2016
Ondřej Cibulka Christoph Vorkötter Adam Purkrt Jakub Holovský Jan Benedikt Kateřina Herynková

This work compares structural and optical properties of silicon nanocrystals prepared by two fundamentally different methods, namely, electrochemical etching of Si wafers and low-pressure plasma synthesis, completed with a mechano-photo-chemical treatment. This treatment leads to surface passivation of the nanoparticles by methyl groups. Plasma synthesis unlike electrochemical etching allows se...

2008
Hyun-jun Cho Jin-Cherl Her Kang-il Lee Ho-young Cha Kwang-Seok Seo

1. Introduction The surface trap of AlGaN/GaN high electron mobility transistors (HEMTs) can cause current collapse phenomenon which is the most serious limiting factor of the device's output power at high frequency operation. The surface passivation is a key step to reduce surface state effects and the quality of surface passivation film is very important [1]. Silicon nitride (SiNX) is widely ...

2014
Hao-Chih Yuan Jihun Oh Yuanchang Zhang Oleg A. Kuznetsov Dennis J. Flood Howard M. Branz

We report solar cells with both black Si antireflection and SiO2 surface passivation provided by inexpensive liquid-phase chemistry, rather than by conventional vacuum-based techniques. Preliminary cell efficiency has reached 16.4%. Nanoporous black Si antireflection on crystalline Si by aqueous etching promises low surface reflection for high photon utilization, together with lower manufacturi...

2016
Zu-Po Yang I-Hsuan Chang Ing-Song Yu

Titanium oxide (TiO2) films and TiO2/SiNx stacks have potential in surface passivation, anti-reflection coatings and carrier-selective contact layers for crystalline Si solar cells. A Si wafer, deposited with 8-nm-thick TiO2 film by atomic layer deposition, has a surface recombination velocity as low as 14.93 cm/s at the injection level of 1.0 × 1015 cm−3. However, the performance of silicon su...

2015
Yuren Xiang Chunlan Zhou Endong Jia Wenjing Wang

In order to obtain a good passivation of a silicon surface, more and more stack passivation schemes have been used in high-efficiency silicon solar cell fabrication. In this work, we prepared a-Si:H(i)/Al2O3 stacks on KOH solution-polished n-type solar grade mono-silicon(100) wafers. For the Al2O3 film deposition, both thermal atomic layer deposition (T-ALD) and plasma enhanced atomic layer dep...

2006
Yong-Mei Xia Zhi-Shan Hua Onnop Srivannavit Ayse Bilge Ozel Erdogan Gulari

Polydimethyl siloxane (PDMS)–glass microchip has a very strong surface effect on polymerase chain reaction (PCR), leading to a very poor PCR yield. In the work reported here, practical dynamic passivation of surfaces of PDMS–glass microchip using polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP) was achieved using a conventional thermocycler. The passivation procedure was cost-effective a...

2007
S. Olibet E. Vallat-Sauvain C. Ballif L. Korte L. Fesquet

Standard surface passivation schemes for crystalline silicon solar cells use SiO2 or SiNx. The c-Si surface passivation mechanisms related with these schemes have been elucidated within the framework of interface recombination modeled by an extended SRH formalism: interface recombination centers characteristic of the SiO2 passivation have larger electron (e) than hole (h) capture cross sections...

2017
Xuefei Li Xiong Xiong Feng Wang Zhenxing Wang Qisheng Wang Bensong Wan Bingchao Yang Yue Wang Wenjing Zhang Qixing Wang Yu Chen Cheng Han Zehua Hu Alexandra Carvalho Joice Sophia Ponraj Zai-Quan Xu Sathish Chander Dhanabalan Youngwoo Son Daichi Kozawa Albert Tianxiang Liu Volodymyr B Koman Qing Hua Wang Michael S Strano

Despite the unique properties of black phosphorus (BP) and phosphorene, including high carrier mobility and in-plane anisotropy, their stability has been hampered by significant crystal deterioration upon exposure to oxygen and water. Herein, we investigate the chemical stability of MoS2-passivated black phosphorus (BP) or bilayer (2L) phosphorene van der Waals (vdW) heterostructures using the ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید