Nickel - B
Special Electroless Nickel - Boron
For High Electrical Conductivity and Oxidation Resistance

Transene's electroless nickel-boron process, NICKEL-B, offers unique characteristics (not equalled by nickel-phosphorous formulations) which are required by many electrical contact and bonding applications. NICKEL-B plates directly on oxide-free nickel / kovar / copper / tin and gold. Plating on non-metallic surfaces may be accomplished by using Transene's RTM Activator and Sensitizer.

Transene's NICKEL-B metallization resists oxidation, has excellent electrical conductivity and may be plated, soldered, brazed or welded. The NICKEL-B plate has a boron content of 2-3%, electrical conductivity approximately equal to 60/40 tin-lead solder and plate hardness of 500 Vickers. NICKEL-B metallizations are more readily soldered than electrolytic nickel and electroless nickel-phosphorus, easily die-bonded using gold-silicon preforms and completely compatible with die attach epoxies.

Ultrasonic or thermal-compression wire bonding of aluminum to NICKEL-B bonding pads can be accomplished with results superior to those employing gold bonding pads. Electrical contacts plated with 0.20 mil NICKEL-B and 10 micro-inches of gold exhibit characteristics (conductivity / hermeticity) equivalent to 50 micro-inches of gold plated on electrolytic nickel.

PROPERTIES OF NICKEL-B

Appearance

Blue solution, pH 8

pH control

Ammonium Hydroxide pH range 7-10

Operating Temperature

60-70 °C

Plating Capacity (50% depletion)

1200 in2/0.5 mil/gal

Nickel metal content

.65 oz/gal

Deposition rate

0.45 mil/hr

Composition of deposit

98% Ni, 2% Boron


PROPERTIES OF DEPOSITED NICKEL-B

M.P.

890 °C

Sp.Gr.

7.85

Coeff. of Expansion

130 x 10-6 in/in/°C

Hermeticity (0.15 mils)

Leak rate: 10-8 cc helium/sec

Reflectivity

65%

Elect. resistivity (0.20 mil)

30 milliohm/sq.

Thermal conductivity

0.01 cal/cm2/cm/°C/sec

Hardness (as plated)

500 Vickers

Solderability (tin-lead)

Excellent-flux not required

Brazing-silver (hydrogen/forming gas)

Excellent @ 500-850


APPLICATION:

Supplied ready-to-use, NICKEL-B operates @ 60-65 °C depositing autocatalytically on appropriate metallic surfaces. (RTM Activator and Sensitizer may be used on non-metallic surfaces.) Applications include: Burn-in contacts, connector pins and sockets, diode cans and transistor headers, heat sinks, lead frames, PC board fingers, capacitor bodies and ceramics.