Semiconductor device manufacturing: process – Coating with electrically or thermally conductive material – To form ohmic contact to semiconductive material
Reexamination Certificate
2002-11-13
2004-09-07
Kielin, Erik (Department: 2813)
Semiconductor device manufacturing: process
Coating with electrically or thermally conductive material
To form ohmic contact to semiconductive material
C427S532000, C427S536000
Reexamination Certificate
active
06787441
ABSTRACT:
TECHNICAL FIELD
The present invention relates a method for depositing an indium oxide or an indium tin oxide thin film on a polymer substrate, and more particularly, to a process in which a surface of a polymer substrate is modified by using an ion beam having an energy and a transparent and conductive indium oxide or indium tin oxide thin film is deposited thereon by an ion assisted deposition and/or an ion beam sputtering method.
BACKGROUND ART
A transparent conductive thin film is electrically conductive and has a high transparency in a visible ray.
By using such inherent property, the transparent conductive thin film is adopted to various fields such as an antistatic film in the optical field such as a Braun tube or glasses, an electrode of an LCD or semiconductors, electrode of solar battery or gas sensor.
Up till now, as a substrate for depositing the transparent conductive thin film, glasses have been used, and in order to fabricate thin films on the glasses, various methods such as an RF-sputtering, a DC-sputtering, a thermal evaporation, a chemical vapor deposition (CVD) and sol-gel method have been used.
Recently, with the development of an electronic industry, products becomes compact and light rapidly. According to the tendency, attempts has proceeded to deposit the transparent conductive thin film on a polymer substrate instead of a glass substrate.
In case of using the polymer substrate instead of a glass substrate, there is advantages that a product can be light and is hardly broken. In addition, since the polymer substrate has a flexibility, it is possible to fabricate a flexible circuit board which would be easily carried.
However, in spite of such advantages, there are many restrictions to use the polymer substrate instead of the glass substrate.
For example, first since the polymer substrate has a low surface energy compared with the glass substrate, it has a weak adhesive force with respect to a thin film to be deposited thereon.
Accordingly, there have been many attempts to increase the surface energy of a polymer, for which plasma or a chemical processing method has been mostly used.
However, these methods have a problem that it does a big physical and chemical damage to the surface of the polymer, the transparency of a substrate is reduced or the adhesive characteristic is not much improved.
In addition, in case that the existing deposition method is used to fabricate the transparent conductive thin film on the polymer substrate, the substrate must be heated at more than 200° C. However, this temperature range is higher than a melting point of the polymer, and then it is difficult to use the polymer as a substrate.
Therefore, an object of the present invention is to provide a method for depositing an indium oxide (IO) and an indium tin oxide (ITO), a transparent conductive thin film, at a low substrate temperature, especially at a room temperature, by using a processing method which does not do any damage to a transparency of a polymer substrate and a chemical stability of a surface-modified layer of a polymer substrate.
DETAILED DESCRIPTION OF THE INVENTION
In order to achieve the above objects, there is provided a method for depositing an IO or an ITO thin film on a polymer substrate, in which oxygen or argon ion beam is applied on a polymer substrate with a certain acceleration energy to modify the surface of the polymer substrate, on which an IO or an ITO thin film is deposited while applying oxygen, argon or oxygen-argon mixed ion beam under vacuum.
In order to achieve the above objects, there is further provided a method for depositing an IO or an ITO thin film on a polymer substrate, including the steps of: applying oxygen or argon ion beam on the polymer substrate with a certain acceleration energy to modify a surface of the polymer substrate; generating an ion beam from a cold cathode ion source by using argon, oxygen or its mixture gas under vacuum; sputtering the ion beam to a target substance consisting of In
2
O
3
or In
2
O
3
and SnO
2
; and depositing an IO or the ITO thin film on the surface-modified polymer substrate.
REFERENCES:
patent: 4560577 (1985-12-01), Mirtich et al.
patent: 5133849 (1992-07-01), Kinoshita et al.
patent: 5783641 (1998-07-01), Koh et al.
patent: 5856858 (1999-01-01), Carey et al.
patent: 0 675 157 (1995-10-01), None
patent: 02-250953 (1990-10-01), None
patent: 03065337 (1991-03-01), None
patent: 04206212 (1992-07-01), None
patent: 06068713 (1994-03-01), None
patent: 06-145964 (1994-05-01), None
patent: 08017267 (1996-01-01), None
patent: 08-017267 (1996-01-01), None
patent: 09-195034 (1997-07-01), None
patent: 10016112 (1998-01-01), None
patent: 10-016112 (1998-01-01), None
patent: 10-186130 (1998-07-01), None
Vossen and Kern, Thin Film Processes, Academic Press: San Diego, 1978 pp. 76-79 and 86.*
W.F. Wu et al., “Deposition of indium tin oxide films on Polycarbonate substrates by radio-frequency magnetron Sputtering” Thin Solid Films, vol. 298 (1997) pp. 221-227.
A.K. Kulkami et al., “Electrical, optical, and structural properties of indium-tin-oxide thin films deposited on polyethylene terephthalate substrates by rf sputtering” J. Vac. Sci. Technol. A, vol. 16, No. 3, (May/Jun. 1998) pp. 1636-1640.
J. Ma et al., “Preparation and characterization of ITO films deposited on polymide by reactive evaporation at low temperature” Applied Surface Science, vol. 151 (1999) pp. 239-243.
Beag Young-Whoan
Cho Jun-Sik
Han Young-Gun
Koh Seok-Keun
Kielin Erik
Korea Institute of Science and Technology
LandOfFree
Method for pretreating a polymer substrate using an ion beam... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for pretreating a polymer substrate using an ion beam..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for pretreating a polymer substrate using an ion beam... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3221662