Structure of amorphous carbon films deposited on Ni nanoparticles under ultrahigh vacuum at room temperature

2016 ◽  
Vol 48 (11) ◽  
pp. 1203-1205 ◽  
Author(s):  
Koji Asaka ◽  
Yahachi Saito
Keyword(s):  
Amorphous Carbon ◽  
Room Temperature ◽  
Ultrahigh Vacuum ◽  
Carbon Films ◽  
Ni Nanoparticles ◽  
Amorphous Carbon Films

OPTICAL PROPERTIES OF TRIMETHYLBORON AND NITROGEN CODOPED AMORPHOUS CARBON FILMS

2002 ◽  
Vol 16 (06n07) ◽  
pp. 1096-1100 ◽  
Author(s):  
Y. HAYASHI ◽  
S. ISHIKAWA ◽  
T. SOGA ◽  
T. JIMBO ◽  
M. ADACHI ◽  
...  
Keyword(s):  
Optical Properties ◽  
Amorphous Carbon ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Carbon Films ◽  
Rf Plasma ◽  
Amorphous Carbon Films ◽  
Fabry Perot ◽  
Pl Emission ◽  
Hydrogenated Amorphous

We report on the efficient photoluminescence (PL) and optical properties of hydrogenated amorphous carbon thin films codoped with nitrogen and trimethylboron (TMB) grown by rf plasma-enhanced chemical vapor deposition at room temperature. The study clearly shows the observation of discrete PL emission peaks. The PL intensity of the film deposited with 20 sccm TMB is more than 103 times than that of the film deposited without TMB. The change of optical bandgap and PL emission energy with TMB flow rate are discussed based on sp3 and sp2 C networks. Angular dependence of the PL spectra revealed that the origin of multiple sharp peaks is due to Fabry-Perot cavity interference effect.

HYDROGENATED AMORPHOUS CARBON FILMS PREPARED BY XeCl EXCIMER PULSED LASER DEPOSITION USING COMPOSITIONAL GRAPHITE AND CAMPHOR TARGET FOR SOLAR CELL APPLICATIONS

2005 ◽  
Vol 19 (11) ◽  
pp. 489-501 ◽  
Author(s):  
M. RUSOP ◽  
X. M. TIAN ◽  
T. SOGA ◽  
T. JIMBO ◽  
M. UMENO
Keyword(s):  
Energy Conversion ◽  
Conversion Efficiency ◽  
Amorphous Carbon ◽  
Room Temperature ◽  
Short Circuit ◽  
Energy Conversion Efficiency ◽  
Carbon Films ◽  
Amorphous Carbon Films ◽  
Hydrogenated Amorphous Carbon ◽  
Hydrogenated Amorphous

Hydrogenated amorphous carbon films ( a - C : H ) were deposited on p -type silicon ( a - C : H / p - Si ) and quartz substrates by excimer laser at room temperature using mixture ratios 1 to 9 and 3 to 7 of camphor to graphite by weight percentages. The presence of hydrogen in the a-C:H films has been confirmed by Fourier transform infrared spectroscopy (FTIR) measurements. The structure and optical properties of a - C : H films were respectively investigated by Raman scattering and UV-visible spectroscopy. The increase of sp 3 sites in the a - C : H films has also been confirmed by the Raman spectra spectroscopy analysis. The increase of the optical band gap with higher camphor percentage in the target was believed to be due to the increase of the sp 3 hybrid forms of carbon arising from camphor incorporation. The formation of a heterojunction between the a - C : H film and Si substrate was confirmed by current–voltage (I–V) measurement. The structure of a - C : H / p - Si cells deposited using mixture ratios 1 to 9 of camphor to graphite by weight percentages showed better photovoltaic characteristics with an open-circuit voltage of 400 mV and short-circuit current density of about 15 mA/cm2 under AM 1.5 (100 mW/cm2 at room temperature) illumination. The energy conversion efficiency and fill factor were found to be approximately 2.1% and 0.38, respectively. The carbon layer contributed to the energy conversion efficiency in the lower wavelength region has been proved by the quantum efficiency measurement.

Deposition of Amorphous Carbon Films by Laser Induced CVD

1987 ◽  
Vol 101 ◽  
Author(s):  
H. Tachibana ◽  
A. Nakaue ◽  
Y. Kavate
Keyword(s):  
Partial Pressure ◽  
Deposition Rate ◽  
Amorphous Carbon ◽  
Cross Sections ◽  
Low Temperatures ◽  
Room Temperature ◽  
Carbon Films ◽  
Auger Analysis ◽  
Amorphous Carbon Films ◽  
Arf Excimer Laser

ABSTRACTAmorphous carbon (a-C) films were prepared by photodissociation of C2H3Cl or CCl4 gas using a pulsed ArF excimer laser (193nm). An increase in the substrate teiperature decreased the deposition rate. For C2H3Cl4 the maximum deposition rate of 10Å/min was attained at a partial pressure of 0.1 Torr and room temperature. In contrast, for CCl4, the maximum deposition rate of 10Å/Min was obtained at a partial pressure of 3 Torr and room temperature. This difference may be attributed to the different absorption cross sections for the two gases. The structural and mechanical properties were leasured. An Auger analysis showed the chlorine content in the a-C film deposited at room temperature to be 1% for C2H3Cl and 8% for CCl4. The Mohs hardnesses of the a-C filis deposited at room teiperature were 7 and 2 for C2H3Cl and CCl4, respectively. It was concluded that both sp2 and sp3 bonds existed between neighboring C atoms at low temperatures, whereas SP2 bond was predominant at temperatures higher than 300°C.

Photoluminescence in Hydrogenated Amorphous Carbon Films Prepared at Room Temperature

1991 ◽  
Vol 30 (Part 2, No. 9A) ◽  
pp. L1539-L1541 ◽  
Author(s):  
Noboru Ohtani ◽  
Masakazu Katsuno ◽  
Toshiro Futagi ◽  
Yasumitsu Ohta ◽  
Hidenori Mimura ◽  
...  
Keyword(s):  
Amorphous Carbon ◽  
Room Temperature ◽  
Carbon Films ◽  
Amorphous Carbon Films ◽  
Hydrogenated Amorphous Carbon ◽  
Hydrogenated Amorphous

Thermal and Mechanical Properties of Diamond-Like a-C:H Films

1992 ◽  
Vol 270 ◽  
Author(s):  
G. Amato ◽  
G. Benedetto ◽  
L. Boarino ◽  
F. Demichelis ◽  
C. F. Pirri ◽  
...  
Keyword(s):  
Amorphous Carbon ◽  
Room Temperature ◽  
Rf Sputtering ◽  
Carbon Films ◽  
Complete Characterization ◽  
Thermal And Mechanical Properties ◽  
Amorphous Carbon Films ◽  
Optical Gap ◽  
Hydrogenated Amorphous

ABSTRACTDiamond-like amorphous carbon and hydrogenated amorphous carbon films (DLC) prepared by rf sputtering have been characterized by means of measurements of optical gap, hardness and Young's modulus. Preliminary results of the application of the photothermal displacement technique (PTD) are also reported, confirming that this method can in principle be applied for a more complete characterization of DLC films at room temperature and low temperatures.

Hard Amorphous Carbon Films Deposited by ArF Pulse Laser Ablation of Graphite at Room Temperature

1992 ◽  
Vol 270 ◽  
Author(s):  
Fulin Xiong ◽  
R. P. H. Chang
Keyword(s):  
Laser Ablation ◽  
Power Density ◽  
Amorphous Carbon ◽  
Laser Power ◽  
Room Temperature ◽  
High Vacuum ◽  
Carbon Films ◽  
Laser Wavelength ◽  
Laser Power Density ◽  
Amorphous Carbon Films

ABSTRACTHard amorphous carbon films have been deposited by ArF pulsed laser ablation of graphite at room temperature, with the laser power density of 5x108 W/cm2. The films prepared in the high vacuum environment possess remarkable diamond-like properties with a hardness up to 38 GPa and an optical energy band gap of 2.4 eV. The properties of the films doped with nitrogen vary with the nitrogen content, but improve interface adhesion, resulting in the extension of the film thickness limit to a greater range. The results suggest that the properties of the laser ablation deposited diamond-like carbon films depend not only on the laser power density, but also strongly on the laser wavelength or photon energy.

Scanning Tunneling Microscopy of Amorphous Carbon Films

1990 ◽  
Vol 48 (1) ◽  
pp. 318-319
Author(s):  
Mircea Fotino ◽  
D.C. Parks
Keyword(s):  
Scanning Tunneling Microscopy ◽  
Amorphous Carbon ◽  
Carbon Films ◽  
Atomic Scale ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Amorphous Carbon Films ◽  
Image Optimization ◽  
Step Procedure ◽  
Stm Images

In the last few years scanning tunneling microscopy (STM) has made it possible and easily accessible to visualize surfaces of conducting specimens at the atomic scale. Such performance allows the detailed characterization of surface morphology in an increasing spectrum of applications in a wide variety of fields. Because the basic imaging process in STM differs fundamentally from its equivalent in other well-established microscopies, good understanding of the imaging mechanism in STM enables one to grasp the correct information content in STM images. It thus appears appropriate to explore by STM the structure of amorphous carbon films because they are used in many applications, in particular in the investigation of delicate biological specimens that may be altered through the preparation procedures.All STM images in the present study were obtained with the commercial instrument Nanoscope II (Digital Instruments, Inc., Santa Barbara, California). Since the importance of the scanning tip for image optimization and artifact reduction cannot be sufficiently emphasized, as stressed by early analyses of STM image formation, great attention has been directed toward adopting the most satisfactory tip geometry. The tips used here consisted either of mechanically sheared Pt/Ir wire (90:10, 0.010" diameter) or of etched W wire (0.030" diameter). The latter were eventually preferred after a two-step procedure for etching in NaOH was found to produce routinely tips with one or more short whiskers that are essentially rigid, uniform and sharp (Fig. 1) . Under these circumstances, atomic-resolution images of cleaved highly-ordered pyro-lytic graphite (HOPG) were reproducibly and readily attained as a standard criterion for easily recognizable and satisfactory performance (Fig. 2).

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