Bulletin of the American Physical Society
68th Annual Gaseous Electronics Conference/9th International Conference on Reactive Plasmas/33rd Symposium on Plasma Processing
Volume 60, Number 9
Monday–Friday, October 12–16, 2015; Honolulu, Hawaii
Session QR2: Plasmas for Nanotechnologies |
Hide Abstracts |
Chair: Tomohiro Nozaki, Tokyo Institute of Technology Room: 308 AB |
Thursday, October 15, 2015 3:30PM - 4:00PM |
QR2.00001: Diagnostics of Nano-Particle Formation in Process Plasmas Invited Speaker: Holger Kersten The main sources of particle generation during plasma surface processing and the formation of nano-composite materials are (i) the formation of large molecules, mesoscopic clusters and particles in the plasma bulk by chemically reactive gases, and (ii) the formation and incorporation of particles at surfaces (target, substrate) by means of plasma-wall interaction. The plasma process promotes the particle formation by excitation, dissociation and reaction of the involved species in the gas phase. The different stages of the particle growth in the gas phase can be observed by various plasma diagnostics as mass spectrometry, laser induced evaporation, photo-detachment, IR absorption, microwave cavity measurements, Mie scattering and self-excited electron resonance spectroscopy (SEERS). Common diagnostics of particle formation also use the observation and analysis of harmonics and other discharge characteristics. Especially the early stages of the particle growth are not well investigated since they are experimentally inaccessible by standard methods as mentioned above. A novel collection method based on neutral drag was tested in order to get a better insight into the early stages of particle growth. The experiments were performed in an asymmetric, capacitively coupled rf-discharge, where multiple growth cycles can be obtained. Making use of the correlation between the particle growth cycles and the bias voltage as well as the phase angle between discharge current and voltage it was possible to monitor each growth process in-situ. This allowed to collect particles at any desired stage of the growth cycle via the neutral drag method. Size distributions of the nanoparticles at the different stages of the growth cycle were determined ex-situ by transmission electron microscopy. The observed correlations of particle size and bias voltage, which can be used for prediction of the particle growth, are qualitatively explained. Furthermore, the change of the electron density in the plasma during the growth cycles has been monitored by microwave interfereomtery and the nano-particle formation and deposition was observed in-situ by XPS and NEXAFS at a synchrotron beamline.\\[4pt] In collaboration with E. von Wahl, A. Hinz, T. Strunskus, V. Schneider, and T. Trottenberg, Institute of Experimental and Applied Physics, University of Kiel, Kiel, Germany. [Preview Abstract] |
Thursday, October 15, 2015 4:00PM - 4:15PM |
QR2.00002: Study on silicon nanocrystals and polymer bulk heterojunction structures Michihiro Sugaya, Yi Ding, Shu Zhou, Tomohiro Nozaki Silicon nanocrystals (SiNCs) and semiconductor-polymer (P3HT) nanostructured thin film is investigated for better understanding of bulk heterojunction structure of hybrid solar cell and improving its photon-to-electron conversion performance. SiNCs are synthesized by VHF plasma CVD using silicon tetrachloride. SiNC thin film transistor (TFT) was fabricated to investigate carrier transport properties of SiNC network. As a result, hydrogen-terminated SiNCs behave as n-type semiconductor materials, and electron mobility of SiNC network is improved dramatically. In contrast, chlorine-terminated SiNCs behave as metallic materials and show poor electron transport property because of surface doping effect: electrons are not flow over the SiNC network due to a large electronegativity of chlorine. Additionally, when the chlorine-terminated SiNCs are blended with P3HT, new peaks appear in FTIR absorption spectrum. The result implies that the thiophene structure, which forms the hole transporting pathway, may be damaged by highly reactive surface chlorine and therefore the hole transport property of Cl:SiNCs/P3HT blended film would be deteriorated dramatically. These results are well correlated with Cl- and H-terminated/P3HT hybrid solar cell performance. [Preview Abstract] |
Thursday, October 15, 2015 4:15PM - 4:30PM |
QR2.00003: High Density Formation of Ta Nanodots Induced by Remote Hydrogen Plasma Yaping Wang, Daichi Takeuchi, Katsunori Makihara, Akio Ohta, Seiichi Miyazaki We have demonstrated the formation of high-density Ta nanodots (NDs) on thermally-grown SiO$_{2}$ by exposing electron beam evaporated a-Ge/Ta bi-layer stack to remote H$_{2}$ plasma without any external heating. After the remote H$_{2}$ plasma exposure, the formation of NDs with an areal density of 9.7 $\times$ 10$^{11}$ cm$^{-2}$ and an average height of $\sim$ 2.1 nm was confirmed. The electrical separation among the Ta-NDs was observed from changes in surface potential due to charging to the dots. XPS analyses indicate etching of a-Ge layer by the remote H$_{2}$ plasma exposure, which was accompanied with agglomeration of Ta atoms on the SiO$_{2}$ surface caused by local heating associated with the recombination of atomic hydrogen on clean Ta-layer surface. [Preview Abstract] |
Thursday, October 15, 2015 4:30PM - 4:45PM |
QR2.00004: Effects of Time Parameter in Pulse Plasma CVD on Narrow-Chirality Distributed growth of Single-Walled Carbon Nanotubes Bin Xu, Toshiaki Kato, Toshiro Kaneko Single-walled carbon nanotubes (SWNTs) are promising materials in industry application, since they have many brilliant characteristics However, since the electronic and optical properties of SWNTs strongly depend on chirality, the selective synthesis of SWNTs with desired chiralities is one of the major challenges in nanotubes science and applications. In this study, time-controlled pulse plasma CVD has been developed aiming for the mass production of narrow chirality distributed SWNTs. Through the comparison of continuous plasma CVD and pulse plasma CVD, it is found that the amount of SWNTs can be increased in keeping with the initial narrow chirality distribution by repeating pulse plasma CVD. The effects of pulse time parameter, plasma off time, on the chirality distribution of SWNTs are also investigated. The chirality distribution becomes narrow with an increase in the plasma off time up to 60 sec, then it becomes broad with an increase in the off time. These indicate, adjustment of plasma time parameter in pulse plasma CVD can improve the uniformity of chirality distribution, resulting in the mass production of very narrow chirality distributed SWNTs. [Preview Abstract] |
Thursday, October 15, 2015 4:45PM - 5:00PM |
QR2.00005: Plasma as a tool for growth of 1D and 2D nanomaterials and their conversions Uros Cvelbar The growth of 1D and 2D nanostructures in low pressure oxygen plasma is presented with the special stress on metal-oxide nanowires and their deterministic growth mechanisms. Since the resulting nanostructures not always have required properties for applications their modifications are required. Therefore their conversions into different oxides or sulphites/nitrides are required with either molecules, atoms, electrons or photons. [Preview Abstract] |
Thursday, October 15, 2015 5:00PM - 5:15PM |
QR2.00006: Controlling silicon/TiN interface by plasma induced functionalization for quantum computing applications Evgeniya Lock, Peng Xu, Yaniv Rosen, Tim Kohler, Aruna Ramanayaka, Joseph Presigiacomo, Mike Osofsky, Mark Kushner, Kevin Osborn Charged tunneling defects at the superconductor-dielectric interfaces are known to be deleterious to quantum bits (qubits) in superconducting quantum computing. These tunneling defects are believed to be charged atoms or groups of atoms which cause qubit decoherence through electric field modes. Here we investigate the interface of TiN/Si, because this material system allows for high-coherence qubits and resonators. The defects on metal-dielectric interfaces are especially important in a nonequilibrium regime when microwave and bias electric fields are applied simultaneoulsy. In this work, we are discussing the effects of plasma produced -O, -N and -F functional groups on the qubits performance. Furthermore, we present a detailed chemical, structural, morphological surface analysis which are correlated with plasma gas phase chemistry. [Preview Abstract] |
Thursday, October 15, 2015 5:15PM - 5:30PM |
QR2.00007: Interface modification and material synthesis of organic light-emitting diodes using plasma technology Rongqing Liang, Qiongrong Ou, Cheng Yang, Kongduo He, Xilu Yang, Shaofeng Zhong Organic light-emitting diodes (OLEDs), due to their unique properties of solution processability, compatibility with flexible substrates and with large-scale printing technology, attract huge interest in the field of lighting. The integration of plasma technology into OLEDs provides a new route to improve their performance. Here we demonstrate the modification of indium-tin-oxide (ITO) work function by plasma treatment, synthesis of thermally activated delayed fluorescence (TADF) materials using plasma grafting (polymerisation), and multi-layer solution processing achieved by plasma cross-linking. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700