Sensors

Gold Plating with Cobalt

Soft gold electrolytes

Auruna® 550 neutral electrolyte deposits pure gold coatings where lifting of fully aqueous resists is an issue, and where excellent bondability and solderability are required. Deposits have excellent ductility, hardness below 90 HK25, low contact resistance, and 99.9% purity. Auruna 550 deposits meet ASTM B488 Type III, Code A.

Auruna 551 mildly acidic electrolyte deposits thin, pure gold (0.05-0.1 μm) as gold strike layers for neutral or alkaline gold plating baths. It provides adhesive activation of the basic material and protects the main gold bath from contamination.

Automobile oxygen sensor

Auruna 553 neutral fine gold electrolyte produces silk-matte coatings of exceptional ductility. Deposits are up to 200 μm; hardness is approximately 90 HV 0.01. Auruna 553 has excellent soldering and bonding properties and meets ASTM B488-01, Type III, Code B.

Auruna 556 neutral electrolyte deposits hard and bright pure gold with a high current efficiency of 90%. 556 is well suited for applications where lifting of the resist by hydrogen should be avoided.

Auruna 5000 neutral electrolyte deposits a fine gold matte yellow microcrystalline coating. Gold layers exhibit excellent bondability and solderability, high ductility and low electrical resistance. Auruna 5000 layers are 99.95% pure gold, with as-plated hardness of 70-85 HV 0.025. Coating meets ASTM B-488-01, Type III, Code A/B.

Hard Gold Electrolytes

Auruna 215 hard gold electrolyte is nickel and cobalt-free.

Auruna 311 gold-cobalt electrolyte was engineered for the direct gold plating of stainless steel, also nickel, tungsten and other challenging substrates. RoHS-compliant coating is ductile, low porosity, corrosion-resistant and cyanide-free.

Auruna 311 is suitable for strike gold layers and thick coatings. It has excellent throwing power, and activates without halogenides. A cobalt-free version is available.

Auruna 530 hard gold-cobalt electrolyte was developed for sensors and electrical contacts. Process provides high current efficiency, hardness of 170 HV 0.01. Bath is mildly acidic. Deposit provides excellent abrasion resistance; maximum thickness is 5 μm.

Auruna 539 hard gold-cobalt electrolyte produces deposits of 99.7% gold, alloyed with cobalt. Baths have excellent throwing power. Ultra-bright deposits have excellent corrosion and abrasion resistance, and a hardness of 200 HV. Auruna 539 was developed for sensor and other technical applications with low coating thickness requirements. Process provides excellent deposit uniformity and a maximum thickness of 2 μm.

Gold Salts

Auruna 6700 Gold Salts are used for cyanide-based gold plating products, whether electrolytic, immersion, or electroless.

Hard Silver as a Gold Replacement

ARGUNA® 630 GAM fine silver electrolyte deposits thick, bright silver layers; it has excellent electrical, bonding and soldering characteristics and a hardness range of 120 HV to 130 HV. 630 is ideal for high mechanical stress applications; a reflection density up to 1.5 GAM, and high temperature resistance, make it an excellent final finish for LEDs. It is also a high-quality conducting material for medical device and aerospace applications.

Bright Silver Electrolyte

ARGUNA 621 deposits semi-bright white coatings. It is carbonate-tolerant, and has excellent throwing power and a wide current density range. For deposition on nickel, strike silver plating is unnecessary.

NTB-302 electrolytic tin produces a uniform coating of pure tin for applications that can’t withstand acidic solutions. Deposited film of electrolytic tin has exceptionally uniform grain structure and excellent solderability.

GRX-70 high-speed electrolytic process dissipates compressive stress, preventing whisker formation. GRX-70 is ideally suited for sensors, connectors and semiconductor lead frames.

Auruna 311 gold-cobalt electrolyte plates gold directly on stainless steel, tungsten and nickel. RoHS-compliant deposit is ductile, low porosity, corrosion-resistant and cyanide-free. Auruna 311 is suitable for gold strike and thick coatings. It has excellent throwing power, and is available in a cobalt-free version.

TWX-40 Reduction Assisted Immersion Gold (“RAIG”) plates, in one step, up to 4-8 μin gold. Using immersion and autocatalytic deposition, deposits are exceptionally uniform and low in porosity, minimizing palladium’s exposure to the environment. TWX-40 is the chemistry of choice for applications requiring heavier gold. It is also valued for its ability to withstand corrosive atmospheres, and for its fast deposition rate.

Gobright TAM-55 immersion gold bath for minimizing nickel corrosion and optimizing gold distribution
Gobright TAM-LC neutral immersion gold bath for SMT
Gobright TAW-66 immersion gold for ENIG; formulated to minimize nickel corrosion
Gobright TCU-38 low gold concentration bath; formulated to minimize corrosion
Gobright TCU-41 direct immersion gold for copper
Gobright TFR-33 immersion gold bath for SMT
Gobright TLA-77 is an alternative autocatalytic gold, a neutral autocatalytic/ electroless gold process

TWX-40 Reduction Assisted Immersion Gold (“RAIG”) plates, in one step, up to 4-8 μin gold. Using immersion and autocatalytic deposition, deposits are exceptionally uniform and low in porosity, minimizing palladium’s exposure to the environment. TWX-40 is the chemistry of choice for applications requiring heavier gold. It is also valued for its ability to withstand corrosive atmospheres, and for its fast deposition rate.

Gobright TMX/21/23 is an alternative autocatalytic gold, a neutral autocatalytic/ electroless gold process.

AubBEL Electroless Gold is a stable alkaline pH autocatalytic processes that deposits greater than 99.9% pure gold at 80 μin/hr. It has excellent gold wire bond characteristics.

Auruna® 7100 operates at high current densities and deposition rates, is ideally suited to reel-to-reel systems. Coatings are brilliant, hard, solderable, and abrasion resistant, with consistently low contact resistance.

Auruna 8100 has highest plating speeds and an extended operating range. Deposits are low-porosity and wear resistant.

Palluna® ACF-100 palladium nickel electrolyte produces ductile, crack-free deposits that resist abrasion. With contact properties comparable to hard gold, it is a cost-effective option; the electrolyte deposits alloy coatings of approximately 80% Pd; hardness is 500-550 HV. ACF-100 is ideal for sensors and electrical contacts.

Rhoduna-Alloy 1 is the world’s first galvanic rhodium alloy. It is a proven alternative to pure rhodium coatings, with low contact resistance, and high corrosion resistance, at a significantly lower cost. Formulated from rhodium and ruthenium, Rhoduna Alloy is a superior surface finish that’s crack-free up to 1 μm. It has a wide current density range, and a deposit hardness of 600-900 HV. Rhoduna-Alloy 1 is ideal for the sensors used in a broad range of applications, and for parts with complex geometries.

Powered by science
Focused on customers

Uyemura GMF finishes lead the world in plating performance.

For more details, or to arrange test processing,
contact your Uyemura representative.

CONTACT