Technologies - 1210 Via Plugging Material
Ink Properties
Glass Transition (Tg): 120°C
Coefficient of Temperature Expansion (CTE): 40 ppm/°C from -50° to +120°
Thermal Conductivity: 2W/M/°K
Volume Resistivity: Less than 1µO-m at 25°C
Sheet Resistivity: < 100 milli O/ /25µ
Shelf Life: 30 days at room temperature or 3 months at -10°C
Adhesion, Tape Test: No material transfer.
Plateability: Compatible with conventional copper plating techniques
Change in physical and electrical properties after temperature cycling: Passes. No electrical failures.
Viscosity: 3,000,000 cps at 0.3 rpm with a Brookfield model LVT with a number LV5 spindle at 25°C.
Specific Gravity: 4 grams/cc
Processing
- Ordinary stencil printing equipment can be used to apply the 1210 conductive material into the via holes.
- Recommended stencil: 4 to 5 mils thick stainless steel. The hole opening in the stencil needs to be 4 to 6 mils larger than the hole diameter in the circuit board.
- An 80 to 90 durometer (hard) squeegee is recommended. This will minimize the tendency of the squeegee to scoop out the material from the via hole in the printing operation.
- Use a squeegee speed of about 2 inches per second. Two of these passes of the squeegee will be needed for each 0.010” of board thickness.
- Via aspect ratios of up to 6:1 (hole depth: hole diameter) have been successfully filled. Printing in both directions is recommended, if possible.
- Recommended curing is 45 minutes at 155°C.
- Clean up solvents are acetone, alcohol, toluene or mixtures.