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==Plasma Enhanced Chemical Vapor Deposition (PECVD)== | ==Plasma Enhanced Chemical Vapor Deposition (PECVD)== | ||
The chemical vapor deposition (CVD) technique is the most popular tool in the deposition of metastable film phase of carbon. A wide variation of this process is now in use. Plasma-enhanced chemical vapor deposition (PECVD) and hot-filament chemical vapor deposition (HFCVD) are among the widely used techniques. The interest in these techniques is due to the potential usefulness in producing diamond films suitable for semiconductor, coatings and other applications. In our previous studies, we have developed a facility which demonstrated both techniques for the synthesis of diamond and diamond-like-carbon (DLC) films. In this project, the locally fabricated facility will be upgraded for the preparation of deposition of diamond and DLC thin films intended for industrial applications. The conditions for deposition using the industrial prototype will be determined. For example, the effects of gas mixture, substrate bias and temperature on the type of film produced will be investigated. Standard surface characterization techniques such as scanning electron microscopy (SEM) , Raman spectroscopy and Fourier transform infrared spectroscopy will be used to confirm the deposits. | |||
The PECVD facility, which is upgraded for better cooling and deposition, is made up mainly of stainless steel. Aluminum electrodes serve as the cathode and anode. Molybdenum cup serves as substrate holder and is placed between the electrodes. Plasma diagnostic is done during deposition with the Langmuir probe. The viewport that is attached in the chamber is also used for spectroscopy and to view the deposition process inside. Thermocouple and ionization gauge are used to observe the substrate temperature and vacuum pressure respectively. The PECVD evolve in a dc discharge plasma process. | |||
==Gas Discharge Ion Source (GDIS)== | ==Gas Discharge Ion Source (GDIS)== | ||
==Electron Cyclotron Resonance Plasma Device (ECR)== | ==Electron Cyclotron Resonance Plasma Device (ECR)== |
Revision as of 19:53, 14 May 2012
Plasma Physics Laboratory (PPL) | |
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Established | late 1980's |
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Type | Research Laboratory |
Coordinator | Dr. Henry J. Ramos |
Adjunct Professor | Dr. Roy B. Tumlos |
Staff | Dr. Luis Ma. Boot |
Address | Plasma Physics Laboratory, National Institute of Physics, University of the Philippines, Diliman, Quezon City, 1101 Philippines |
Contact | plasma@nip.upd.edu.ph |
Website | [1] |
About Us
Plasma technology has become one of the major and important technologies in the development of materials. In the late 1980's, the Plasma Physics Laboratory (PPL) of the National Institute of Physics in U.P. Diliman was established by Dr. Henry J. Ramos to experiment with and develop modest plasma systems in order to acquire practical knowledge and skills to better employ technologies based on plasma physics. With grants extended by various agencies like the National Research Council of the Philippines (NRCP), the Third World Academy of Sciences (TWAS), the Office of Research Coordination of the University of the Philippines (ORC-UP), the Engineering and Science Education Program of the Department of Science and Technology (ESEP-DOST), the DOST-Grants-in-Aid, and the Japan Society for the Promotion of Science (JSPS), the PPL has built some major plasma devices over the years.
These facilities have undergone modifications and upgrading to serve as demonstration-of-principle devices for specific applications. For example, the PSTNIS facility has been designed as a source of ions for ion implantation applications. It has been utilized as well for the synthesis of nitrides (TiN, ZrN) on metal substrates. On the other hand, the SPNIS facility has also been used for the formation of TiN on metal substrates. Diamond and diamond-like-carbon (DLC) films on silicon have been deposited using the PECVD device. Various studies have been done on these facilities leading to several publications and conference papers.
Research Machines
Plasma Sputter-Type Negative Ion Source (PSTNIS)
A sequence of accelerators and focusing techniques are employed in the extraction of gas/metal ions produced in a sputter-type ion source. Enhancement of ion yield is tried with noble gases as well as with cesium vapors. The extracted and highly focused beam is studied in terms of its transport properties specifically on techniques of increasing acceleration voltage reaching to several keV. The ion current is expected to increase with increasing acceleration voltage. Acceleration voltages in the order of a few keV and a few hundred nanoamperes of ion current are essential in ion beam implantation and etching applications. Ion beam etching is necessary in the preparation of materials for various investigations such as thinning of samples for transmission electron microscopy or for texturing surfaces in the semiconductor industry. High-energy particles (ions or neutral particles) bombard the specimen in the physical process. Ion beam etching has merits over conventional metallographic etching methods specially when etching composite materials or material compounds. The production of highly energetic ions in this study is the first step towards comprehensive etching tests and parameter studies to be done on various materials.
Sheet Plasma Negative Ion Source (SPNIS)
The sheet plasma negative ion source (SPNIS) was also designed by Dr. Henry J. Ramos. It is the first plasma facility in the Philippines.
The original SPNIS chamber was made of borosilicate glass until it was upgraded into an all-stainless steel chamber for easier operation and safety. In this manner, the plasma can be operated at higher currents without danger of implosion as would be feared if the chamber was made of glass. In the production region , thermionic electrons are produced by passing current through tungsten filaments. The gas molecules (such as hydrogen, nitrogen, and argon), that are injected into the chamber through the gas inlet port, are ionized due to collision with the thermionic electrons. A large diameter plasma is produced in a dc discharge between the cathode and anode through the two intermediate electrodes. In the extraction region , the usually cylindrical plasma is converted to a sheet configuration using a pair of samarium-cobalt (Sm-Co) permanent magnets with the north poles facing each other. This wide area plasma is focused on a hearth near the anode for application in coating of large area. A titanium disk target is placed at the anode and is sputtered by the plasma for purposes of deposition. There is a port for langmuir probe and a space for the mass analyzer for plasma characterization. In between the two regions are the plasma limiters that provide the magnetic field in the constriction. A coreless electromagnet is enclosed inside the first plasma limiter, while a ferrite magnet is located inside the second plasma limiter.
Preliminary studies on deposition of different cermet on various substrates such as aluminum, stainless steel and copper has been done on this machine. Among the deposited layers are Sn-Bi, TiCN, TiCuN, TiAlN, and TiN.
Plasma Enhanced Chemical Vapor Deposition (PECVD)
The chemical vapor deposition (CVD) technique is the most popular tool in the deposition of metastable film phase of carbon. A wide variation of this process is now in use. Plasma-enhanced chemical vapor deposition (PECVD) and hot-filament chemical vapor deposition (HFCVD) are among the widely used techniques. The interest in these techniques is due to the potential usefulness in producing diamond films suitable for semiconductor, coatings and other applications. In our previous studies, we have developed a facility which demonstrated both techniques for the synthesis of diamond and diamond-like-carbon (DLC) films. In this project, the locally fabricated facility will be upgraded for the preparation of deposition of diamond and DLC thin films intended for industrial applications. The conditions for deposition using the industrial prototype will be determined. For example, the effects of gas mixture, substrate bias and temperature on the type of film produced will be investigated. Standard surface characterization techniques such as scanning electron microscopy (SEM) , Raman spectroscopy and Fourier transform infrared spectroscopy will be used to confirm the deposits.
The PECVD facility, which is upgraded for better cooling and deposition, is made up mainly of stainless steel. Aluminum electrodes serve as the cathode and anode. Molybdenum cup serves as substrate holder and is placed between the electrodes. Plasma diagnostic is done during deposition with the Langmuir probe. The viewport that is attached in the chamber is also used for spectroscopy and to view the deposition process inside. Thermocouple and ionization gauge are used to observe the substrate temperature and vacuum pressure respectively. The PECVD evolve in a dc discharge plasma process.
Gas Discharge Ion Source (GDIS)
Electron Cyclotron Resonance Plasma Device (ECR)
Streaming Neutral Gas Ion Source (SNGI)
Diagnostic tools and techniques used by the laboratory are the following:
- Spectroscopy
- Langmuir Probe
- Mass Spectroscopy
- E x B Analyzer
Source: http://www.nip.upd.edu.ph/plasma/