MAR CT-74 provides a minute, highly charged colloid which promotes a uniform, highly adherent electroless copper deposit. CT-74 is a very stable chemistry with a low halogen content which minimizes copper attack and produces an absorbent palladium deposit.

Advantages of the MAR CT-74 process include:
  • Less decay of the catalyst providing a longer process life
  • The MAR CT-74 has a low halogen content which provides a more stable solution than sulfate based systems.
  • Deposits small colloid structure which will produce a dense electroless copper deposit.
  • Provides highly active sites of catalyst resulting in a uniform hole wall coverage.
DI Water 96% of working bath
MAR CT-74 3%
Hydrochloric Acid 1% of final volume of working bath
PD-70C 240 g/l
  1. Fill tank with 96% of DI water.
  2. Add 1% by volume of Hydrochloric Acid.
  3. Add 240 g/l of PD-70C to the acidified DI water. Mix till PD-70C is totally dissolved.
  4. When pre-dip is finally dissolved, add 3% of CT- 74.

MAR CT-74 should be discarded when copper metal exceeds 1 g/l (1000ppm)

Optimum Range
MAR PD-70C 240g/l 240g/ l± 24 g/l
Normality 0.80 0.60 – 1.0N
Temperature 30°C 21 - 43°C
Stannous Chloride 17 g/l 15 – 30 g/l
Palladium Metal 0.240 g/l 0.200 – 0.240 g/l
3% 2.50 – 3.00%
Time 5 min 4 – 8 min
Square foot replenishment 0.30 ml/ssf 0.30 – 0.40 ml/ssf

***Analysis to be done daily***

Never add water to catalyst bath. Bath should be replenished with a MAR PD-70C made solution when level drops. Make MAR PD-70 solution using the same make-up listed above without adding MAR CT-74 catalyst.

Tanks: Polypropylene, HD Polyethylene, PVC
Heaters: Teflon, Teflon coated SS, Quartz
Ventilation: Required.
Filtration Recommended. Continuous filtration through a 10 micron polypro filter tube is advisable at 3 to 4tank volume turnovers per hour.
Agitation: Recommended. Work rod agitation to maximize movement of solution through holes is recommended. DO NOT USE AIR AGITATION!!
Vibration: Recommended for small hole and high aspect ratio boards.
  1. Reagents Required
    1. 0.1N Iodine solution
    2. Starch Indicator Solution
    3. 250 ml. Erlenmeyer Flask
    4. 50 ml. burette
    5. 5 ml. pipette
  2. Method
    1. Pipette a 5ml sample into a 250ml Erlenmeyer Flask.
    2. Add 100 ml of DI water
    3. Add 2 mls of 2% starch solution
    4. Titrate with 0.1N iodine solution to a blue endpoint which lasts for at least 30 seconds.
  3. Calculation
    1. g/l stannous chloride = mls 0.1N iodine x 2.257

    Maintain between 15 – 30 g/l

Please note that the information above for this chemical is partial. Click the button below to request full technical information sheet.
Request Technical Information Sheet

Quick Contact