Cleaner – Epithas® MCL-10 acid soak cleaner removes surface oils and contamination and wets the surface to enhance solution transfer. (Also available: MCL-067 CMOS-compatible, low-foaming acid soak cleaner.)
Micro-etch – removes copper surface oxide and roughens the copper, enhancing nickel adhesion.
Acid rinse – ensures that the copper surface is oxide-free and residual copper has been removed.
Pre-dip – minimizes acid dilution of the subsequent activator bath.
Electroless nickel – NPR-18 electroless nickel is a mildly acidic plating bath for fine line circuitry in silicon wafer plating. Bath formulation allows deposition of electroless nickel without bridging. Highly stable, easy to use; 6-8% phosphorus content as-plated.
Epithas NPR-24, is a mildly acidic electroless nickel formulated for fine line circuitry in silicon wafer plating. This bath allows the deposition of EN without bridging; easy to use and optimized for automatic solution control using the Uyemura STARLiNE DASH controller.
Immersion gold – TDS-20 cyanide-free immersion gold bath was engineered for surface mount applications and wafer plating. Neutral pH; will not corrode the underlying nickel. Provides excellent solder joint reliability, including small solder balls. The thin gold coating maintains long-term solderability and prevents nickel oxidization and passivation.
Autocatalytic gold – Epithas TMX-16 electroless gold for silicon wafers is cyanide-free, with a neutral pH. Ideal for surface mount and wafer plating. Will not corrode the underlying nickel, thus it provides excellent solder joint reliability.
CMOS-Compatible Process for Copper Metallization
Cleaner – Epithas CACL-067 acid soak pretreatment for silicon wafer plating, including SOI wafers.
Micro-etch – Epithas LEC-19 removes naturally-occurring oxidation from aluminum and aluminum alloy surfaces. Pretreatment for electroless nickel on aluminum for silicon wafers, including SOI wafers.
Electroless Nickel – Epithas NPR-18CM – for wafer plating, including SOI wafers, involving fine line circuitry.
Read about our UBM process for aluminum
Read Under Bump Metallization: Some Economical Alternatives published in US Tech.