www.changsung.com
ISO/TS 16949
KS Q/ISO 14001
OHSAS 18001
CONDUCTIVE PASTES
Offices and Factories in Korea
China
620-8 Namchon-dong, Namdong-gu,
Incheon, Korea
Tel: 82-32-450-8770 Fax: 82-32-450-8870
Weihai
4FL, Kukje Bldg, 127-1, Nonhyun-dong, Kangnam-gu,
Seoul, Korea
Tel: 82-2-512-3793
Fax: 82-2-512-3214
Pyeongtaek
San 13-5, Goryeom-ri, Cheongbuk-myeon, Pyeongtaek-si,
Gyeonggi-do, Korea
Tel: 82-31-683-2466 Fax: 82-31-683-2465
Cheongju
8-8 Poongjung-ri, Naesu-eup, Cheongwon-gun,
Chungbuk, Korea
Tel: 82-43-213-8801 Fax: 82-43-213-8807
Materials for a high-tech revolution
Offices and Factories Overseas
Headquarters & Incheon Factory
International Business Center
CONDUCTIVE
PASTES
Innovative Technological Advancements
Innovative materials to perfect advanced technology The applications for Chang Sung Corporation’s conductive pastes range from
uses in alternative energy to high efficiency energy industries. They are
made from advanced materials and ideal for high-tech electric components.
Changxing Road, First Industrial Complex, Huanshan RD,
Economic Technological Development Zone,
Weihai City, Shandong Province, China
Tel: 86-631-596-5931 Fax: 86-631-596-8160
Dongguan
Huangkeng Industrial Area, Shilongkeng Village,
LiaoBu Town, Dongguan City, Guangdong Province, China
Tel: 86-769-8352-1800 Fax: 86-769-8352-1803
Japan
Bansui Bldg. 2F, Toranomon 1-5-16,
Minato-Ku Tokyo, Japan 105-0001
Tel : 81-3-5512-5380 Fax: 81-3-5501-3234
PA-110520
CSC’s CONDUCTIVE PASTES
CONNECTING
CURRENT TECHNOLOGY
TO THE FUTURE
Innovative power to perfect high technology
CSC’s conductive pastes are made with advanced materials and can play an innovative role
in making electric components highly functional.
With our strong commitment to developing innovative technology, we strive to supply the
highest quality conductive pastes to the global maket.
Our efforts have come to frution under our new ”Paron” product line.
R&D CENTER
Our forward thinking research team is at the heart of our
creative spirit and progressive technology.
CUSTOMIZED SERVICE
CSC provides skillful and prompt responses to all our
customers’ needs through careful consultation and
technical cooperation.
ECO-FRIENDLY MATERIALS
Going forward, the solutions to any problems with
electronic components need to be resolved with ecofriendly materials.
CSC is committed to developing the greenest and
safest conductive pastes possible.
01
::: Chang Sung Corporation
Conductive Pastes :::
02
CONDUCTIVE PASTES
TYPES OF CONDUCTIVE PASTES
CONDUCTIVE
PASTES
Conductive pastes are well-distributed compounds of metal powders
or inorganic powders in organic fluid vehicle systems. They are produced by mixing
conductive fillers, organic vehicles (solutions of polymers in solvents),
glass frits, ceramic powders, and several kinds of additives through a process of printing,
spraying, or dipping and then drying or heating.
Types of Conductive Pastes
MANUFACTURING PROCESS
CURING TYPE
FIRING TYPE
LOW TEMPERATURE
CONDUCTIVE PASTES
CONDUCTIVE PASTES
SINTERING PASTES
Membrane Touch Switches
PCB Through-Holes
Flexible Printed Circuit Boards
Touch Screen Electrodes
RFID Tag Antennas
Insulation Coatings
Chip Varistors
Chip Inductors
MLCC
Silicon Solar Cells
Dye-Sensitized Solar Cells
Piezo / Microwave Products
Low Temperature Sintering Pastes
CHANG SUNG
CORPORATION IS A
LEADING
PRODUCER OF
CONDUCTIVE
PASTES
1_Metal Powder
The special characteristics of various metal
powders (particle size, distribution and
morphology) are controlled by our
advanced powder manufacturing
processes.
2_Premixing
Inorganic powders including metal powders
are moistened evenly by premixing them
with vehicles(solutions of polymers in
solvents) before the dispersion process
begins.
3_Dispersion
The aggregations of metal powder are
separated into individual particles and are
then completely mixed and stabilized by an
organic vehicle.
4_Inspection
Final products are thoroughly inspected based
on our customers’ specifications.
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::: Chang Sung Corporation
Conductive Pastes :::
04
CONDUCTIVE PASTES
CURING TYPE CONDUCTIVE PASTES
CONDUCTIVE PASTES
CURING TYPE CONDUCTIVE PASTES
CURING TYPE CONDUCTIVE PASTES
PASTES FOR MEMBRANE TOUCH SWITCHES
Product No.
Filler
Curing Conditions
Resistance (mΩ/ /mil)
Viscosity (Pa s)
Comments
15~50
20
15
15~30
50
40
40,000
15
15
20
25
20
15
20
Low resistivity
Halogen free, Low resistivity
Halogen free, Excellent flexibility
Low temperature curing
Low cost
Carbon blended, Low cost
Excellent flexibility
Main Features
- Membrane touch switches
- Flexible circuits
- Heating elements
- High conductivity
- Excellent flexibility
- Fine line resolution
Paron-910, 960, 950
PASTES FOR PCB THROUGH-HOLES
Product No.
Paron-621
Paron-650
Paron-630
Filler
Curing Conditions
Ag
(Ag/Cu)
C
50°C, 70°C,150°C
/each 30min
150°C/30min
Applications
Resistance (mΩ/ /mil)
Paron-810
Ag
Paron-810A
Paron-810E Ag+Ni
Paron-811
Ag
Paron-811A
30
30
60
30
30
130°C/30min
Applications
Viscosity (Pa s) Fine line width(μm
25
25
20
80
70
100
100
200
50
70
Comments
Resistive type touch screens
Capacitive type touch screens
Main Features
- Resistive type touch screens - High conductivity and low contact resistance
- Capacitive type touch screens - Excellent adhesion to ITO electrodes and PET film
- Fine line resolution
Paron-811
PASTES FOR RFID TAG ANTENNAS
Viscosity (Pa s)
6
6
15
200
2 X 105
Comments
High reliability, Low resistivity
Low cost
Low resistivity
Main Features
- Double sided PCBs
Product No. Filler Curing Conditions Resistance (mΩ/ /mil)
CURING TYPE CONDUCTIVE PASTES
CURING TYPE CONDUCTIVE PASTES
Paron-910 Series
130°C/30~60min
Paron-961
140°C/30~60min
Paron-960
Ag
Paron-950 Series
80°C/30~60min
Paron-931
Paron-930
Ag + C 130°C/30~60min
Paron-920
C
Applications
PASTES FOR TOUCH SCREEN ELECTRODES
Product No.
Paron-320
Paron-321
Paron-322
Filler
Ag
Resistance (mΩ/ /mil)
Viscosity (Pa s)
130°C/20min
10
20
50
25
25
25
Ag/Cu
Applications
- High conductivity
- Excellent adhesion to Cu plates and phenolic boards
- No defects such as pinholes or cracks
Curing Conditions
Comments
Low resistivity
High resolution
Low cost
Main Features
- 13.56MHz & 900MHz
- RFID Tag Antennas
- High conductivity
- Excellent adhesion to PET and PI film
- Fine line resolution
Paron-320
Paron-650
PASTE FOR INSULATION COATINGS
PASTES FOR FLEXIBLE PRINTED CIRCUIT BOARDS
Product No.
Paron-610
Paron-611
Paron-612
Filler
Ag
Curing Conditions
150°C/30min
Resin
Applications
- Shielding for flexible PCBs
- Conductive circuits for flexible PCBs
Resistance (mΩ/ /mil)
Viscosity (Pa s)
200
-
25
25
25
Comments
Low cost
High reliability, Low resistivity
Excellent flexibility
- Excellent adhesion to PI film
- Excellent flexibility
::: Chang Sung Corporation
Curing Conditions
Insulation Resistivity (mΩ/ /mil)
Viscosity (Pa s)
Comments
1010
15
15
Green
Colorless & Transparent
Paron-310
300 ~ 600 mJ/cm
Resin
Paron-310T
500 ~ 1,000 mJ/cm2
2
Applications
- Insulation Coatings
- Spacers
Main Features
Paron-610
05
Product No. Filler
Main Features
- Excellent insulation resistance
- Excellent adhesion to treated or untreated PET film
- Excellent flexibility
Paron-310
Conductive Pastes :::
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CONDUCTIVE PASTES
FIRING TYPE CONDUCTIVE PASTES
CONDUCTIVE PASTES
FIRING TYPE CONDUCTIVE PASTES
FIRING TYPE CONDUCTIVE PASTES
PASTES FOR CHIP VARISTORS
Product No.
Filler
Paron-V10
Paron-V23
Paron-V22
Paron-V27C
Pd
Ag/Pd=7:3
Ag/Pd=8:2
Ag
Firing Conditions
1,100 ~ 1,300°C
950 ~ 1,150°C
900 ~ 1,050°C
600 ~ 800°C
Applications
Viscosity (Pa s)
50
30
35
45
Comments
Product No.
High reliability
Electrical property control
Electrical property control, Low cost
Excellent solderability
Main Features
- Internal and terminal
electrodes of Chip Varistors
Filler
Silver Content(%)
Ag
80 ~ 86
Paron-S81
Paron-S82
Al
High reliability
Excellent electric properties
Cp controlled with the same metal contents
Paron-V27C
Viscosity (Pa s)
250
700 ~ 800°C/2~5sec
(Actual peak temperature)
70 ~ 82
Applications
- Internal electrode
Firing Conditions
50
Comments
Pb & Cd free - Suitable for SiNx
Low contact resistance
Excellent adhesion to the Si-wafer
Smooth surface
Paron-S81
Main Features
- Front electrodes for Si solar cells
- Back surface electrodes for Si solar cells
- High reliability
- Excellent electric properties
- Excellent adhesion to the Si-wafer
Paron-S82
- Terminal electrodes
Paron-V10, V23
Excellent solderability
Strong adhesion strength
PASTES FOR CHIP INDUCTORS
Product No.
Filler
Silver Content(%)
Firing Conditions
Ag
85~90
86~88
55~65
850 ~ 900°C
850 ~ 900°C
600 ~ 800°C
Paron-L61
Paron-L69
Paron-L65
Applications
PASTES FOR DYE-SENSITIZED SOLAR CELLS (DSSC)
Viscosity (Pa s)
200
50
Main Features
- Internal and terminal electrodes
Product No.
Excellent conductivity
Excellent line resolution
Excellent solderability
Firing Conditions
Viscosity (Pa s)
Paron-S83
Ag
83 ~ 86
450 ~ 500°C/30min
150
Paron-S84
Glass
65 ~ 75
500°C/30min
100
Comments
Excellent adhesion to the substrates
Low contact & Line resistance
Excellent durability in electrolytes
Excellent adhesion
Main Features
- DSSC
- Ag Paste
Conductive electrodes for glass substrate
Electrode Protection
- Terminal electrodes
Low contact resistance
Good adhesion
Paron-S83
- Glass Paste
Paron-L61, L69
Excellent durability
Excellent adhesion
PASTES FOR MLCC
PASTES FOR PIEZO/MICROWAVE PRODUCTS
Product No.
Filler
Firing Conditions
Viscosity (Pa s)
Paron-C78N
Ni
1,200 ~ 1,300°C
18
Paron-C77C
Cu
800~850°C
35
Applications
- Internal and Terminal electrodes of MLCC
- Inert and reducing atmosphere
Comments
High degree of dispersion
Thin and uniform thickness
Good thermal match to ceramics
Main Features
- Internal electrodes
Paron-C77C
High degree of dispersion
Thin and uniform thickness
Low shrinkage
- Terminal electrodes
Good adhesion
Good thermal match to ceramics
::: Chang Sung Corporation
Silver Content (%)
Applications
High reliability
Fine line resolution after printing and firing
Excellent surface roughness
Excellent solderability
Strong adhesion strength to ceramics
07
Filler
Paron-L65
- Internal electrodes
Multilayer inductors
Chip beads
Power inductors
Common mode filters
Comments
Paron-C78N
Product No.
Filler
Silver Content (%)
Firing Conditions
Viscosity (Pa s)
Ag
60
80
80
50
750 ~ 850°C
800 ~ 890°C
830 ~ 880°C
800 ~ 890°C
100
200
200
100
Paron-P96
Paron-W38
Paron-W38A
Paron-W38E
Applications
- GPS Patch Antennas
- Dielectric Chip Antennas
- Piezo-Electric Products
Main Features
Comments
Controlled shrinkage
High Q-factor
High solder resistance
High Q-factor, Low cost
Paron-P96
- Piezo Products
Excellent solderability
Strong adhesion to piezo ceramics
- Microwave Products
Paron-W38
High solder resistance
Excellent adhesion strength
Conductive Pastes :::
08
FIRING TYPE CONDUCTIVE PASTES
FIRING TYPE CONDUCTIVE PASTES
PASTES FOR SILICON SOLAR CELLS
CONDUCTIVE PASTES
LOW TEMPERATURE SINTERING PASTES
LOW TEMPERATURE SINTERING PASTES
LOW TEMPERATURE SINTERING PASTES
Product No.
Filler
Sintering Conditions
Specification
Sheet Resistivity
2mΩ/ /mil
Thermal Conductivity
> 80 W/m K
Super height 100um
Sheet Resistivity
8mΩ/ /mil
Paron-350
Ag
150°C/20min
Paron-351
Ag
170°C/20min
Paron-352
Ag
170°C/20min
Paron-353
Ag
(Ag/Cu)
170°C/20min
Sheet Resistivity
12mΩ/ /mil
Paron-360
Cu
250°C/20min
Sheet Resistivity
4mΩ/ /mil
Comments
Excellent Conductivity
Screen printing, R2R printing
High Thermal conductivity
Good adhesion to substrates
High conductivity after sintering
Screen printing
CONDUCTIVE
PASTES :
APPLICATIONS
Thinner, Lighter, and More Economical
CSC conductive pastes add greater flexibility
and value to leading edge technology.
Good hole plugging
Excellent chemical stability
Low cost compared with silver
Good conductivity
Screen printing, R2R printing
Applications
FPCB(Flexible Printed Circuit Board)
RFID Tags
Solar cells
Electromagnetic shielding patterns
Touch sensors
LED Die Attach Adhesive
B2it Bump
PCB Hole Plugging
150 ~ 200
Sintering
Main Features
- Low temperature sintering
- Excellent conductivity
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::: Chang Sung Corporation
Conductive Pastes :::
10
CONDUCTIVE PASTES
CSC’s
R&D CENTER
RESEARCH & DEVELOPMENT
MATERIALS
TO COMPLETE A VARIETY
OF PRODUCTS
The R&D center at Chang Sung Corporation
is at the heart of developing
and advancing our conductive paste products for a brighter future.
EQUIPMENT
Scanning Electron Microscope
Laser Particle Size Analyzer
Surface Area Analyzer(BET)
Atomic Absorption Spectrometer
Optical Emission Spectrometer
Optical Microscope
Stereo Microscope
Thermal Analysis Equipment (TG/DTA)
Differential Scanning Calorimeter
Vibrating Sample Magnetometer
Universal Testing Machine
Color and Color Difference Meter
Electrolysis Analyzer
Sonic Sifter
Oxygen / Nitrogen Analyzer
Hardness Testers
Electric Furnaces
Zeta Potential Meter
B-H Analyzer
Gloss Meter
FT-IR
Dilatometer
Solar simulator
Color 3D laser scanning microscope
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::: Changsung Corporation
Conductive Pastes :::
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CONDUCTIVE PASTES
GUIDE TO SCREEN PRINTING PROCESS
CONDUCTIVE PASTES
GUIDE TO SCREEN PRINTING PROCESS
PHYSICAL PROPERTIES OF CONDUCTIVE PASTES
1. Screen
4. Characteristics of a print
The frame must be flat enough to ensure that it is parallel to the
substrate surface. The mesh materials should be flexible to
conform to the surface variation of the component being printed
and sufficiently resilient to return to its original shape after
passage of the squeegee. The screen tension should be
sufficient enough to stretch the mesh and cause the screen to
peel away from the substrate after printing.
There are three important characteristics of a print during the
printing process. Its shape, position and thickness must be
controlled exactly to get the best quality print.
various rates of shearing, the “up” and “down” curves of
thixotropic flow do not coincide. This “hysteresis loop”
is caused by the decrease in fluid viscosity with the increasing
time of shearing.
The thixotropic index is a measure of the thixotropic property of
the non-Newtonian fluid. A common method for characterizing
and quantifying TI is to figure the ratio of the fluid viscosity as
measured at two different speeds (with the same spindle). These
measurements are usually made at speeds that differ by a factor
of 10(for example, 10 and 100 rpm). TI can be expressed as
below;
1) Shape
2. Squeegee
The squeegee material should be resistant to the solvents,
vehicles and screen cleaner. Polyurethane is the most popular.
The width of the squeegee must be large enough to depress the
mesh evenly across the printed area of the screen. The distance
from each end to the frame will depend on the type of mesh, its
tension, the screen gap, the hardness of the squeegee and the
size of the printing pattern. Wear is a slow process and any
deterioration of the print quality is not easily observed, so the
squeegee should be checked before every use.
3. Process variables
Pressure uniformity along the length of the substrate is ensured
by having the squeegee pressures be 0.2~0.5Kg/cm of the
squeegee length. For good thickness uniformity, it is helpful to
increase the squeegee pressure. On very uneven surfaces,
pressure must be increased and the use of a more flexible mesh
is advantageous.
2) Squeegee speed
For high viscosity, appropriate thinness and good repeatability, a
range of 50~300mm/sec is required.
B
C
D
A
Defect
Ideal
B
Line widening
C
Scalloping of edges
D
Marked screen pattern
E
Bleed out on edges
F
G
H
I
Smearing
Broken line
Uneven thickness
Lines not full width
E
F
G
H
I
Cause
Yield point too Low
Viscosity too low
Viscosity too high
Squeegee pressure too high
Yielding point too high
Improper wetting
Filler too coarse
Too much surfactant
Step on substrate too sharp
Poor screen alignment
Screen gap too large
2) Position
Print thickness decreases as the squeegee becomes more
perpendicular to the screen surface. High squeegee pressure,
high paste viscosity, high squeegee speed and the use of
stainless steel mesh will decrease the attack angle more.
Three point location (Three fixed stop) gives a unique position
providing a vacuum to hold the component down in the fixture.
The component should be surrounded by a squeegee support to
press the screen against the edge of the component. The
component must protrude slightly (0.1~0.2mm) above the
surrounding.
3) Thickness
The parameters effecting print thickness.
Poor fill and
Good fill
good clearance and clearance
Good fill and “60 degree”squeegee
poor clearance but 45 degrees at tip
4) Screen gap
The stripping action can be controlled by adjustment of the
screen gap. The screen gap required will vary with screen
tension, image area, ink viscosity, squeegee speed, etc. A good
starting figure can be obtained by multiplying the width of the
screen by 0.004 for stainless steel, 0.006 for polyester, and
0.010 for nylon.
5) Down stop
The squeegee may be prevented mechanically from descending
below a set height, corresponding with a position slightly below
the component surface. The drop of the squeegee is placed
approximately 0.1mm below the top of the component by using
a down stop.
13
::: Changsung Corporation
Variable
Squeegee pressure
Squeegee speed
Squeegee angle
Printer
Squeegee hardness
Screen gap
Down stop
Theoretical paste volume
Process Emulsion thickness
Paste viscosity
Temperature
Others Squeegee wear
Screen tension
2
Viscosity
Viscosity is the most widely used parameter to assess a paste s
flow behavior. It is the internal resistance exerted by a fluid to
the relative motion of its parts and is expressed in units of
pascal seconds (Pa sec). It is defined as shear stress divided by
shear rate, where shear stress is the force in pascals applied to
a viscous fluid to cause its movement, and shear rate, in
reciprocal seconds, is the rate of travel of two parallel plates
separated by a fluid, divided by the distance between the
plates(cm/sec cm-1=sec-1).
It can be expressed as follows:
= Viscosity =
High
thin
thick
thin
thin
thick
thick
thick
thick
thick
thin
thick
thick
Low
thick
thin
thick
thick
thin
thin
thin
thin
thin
thick
thin
thin
=
Viscosity at low rpm
Viscosity at high rpm
The TI of the paste must be optimized because the rheological
behavior of the paste has a profound effect on the quality of
screen printing.
Viscometer : Brookfield HBDV- +
Standard : ASTM D 2196-86
Shear stress(Pa)
F
=
Shear rate(sec -1)
S
(1Pa s = 10poise = 1000cps)
Viscometer
3) Attack angle
1
CONDUCTIVE PASTES
CONDUCTIVE PASTES
1) Squeegee Pressure
TI =
A
PHYSICAL PROPERTIES OF CONDUCTIVE PASTES
Brookfield HBDV-ll+
RION VT-04
Malcom : PCU-205
Resistivity
Standard : JIS K 7117
Thixotropic Index (TI)
The flow behavior of conductive paste, which is the mixture of
inorganic filler and organic vehicle, is referred to as the
thixotropic flow. In the figure below, various types of flow
behavior are illustrated.
The resistivity of the conductive film is usually expressed as
sheet resistivity, which is the resistance of the unit area at a
given thickness. Resistivity(R) is calculated using the following
equation:
R=
s
T
L
(ohm)
W
T : thickness (mm)
W : width (mm)
L : length (mm)
s : resistivity coefficient
Sheet resistivity(R’s) is obtained by dividing R with L/W.
The standard resistivity(Rs) is defined as the resistivity of a
standard film thickness. The standard resistivity of 15 m film
thickness is shown below ;
Rs = R s
a : Newtonian flow
b : Dilatant flow
c : Pseudoplastic flow
d : Thixotropic flow
Tm
15
Tm : measured thickness ( m)
mΩmeter : HIOKI 3540
Surface Resistance Tester : CMT-1000N
A thixotropic flow undergoes a decrease in viscosity with time,
while it is subjected to constant shearing. When subjected to
Conductive Pastes :::
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