Additives that brighten and level acid copper deposits
Acid copper plating additive systems consist of three components — brightener (SPS-type), leveler and carrier (PEG-type) — that work together to improve the brightness, flatness, ductility and through-hole / blind-via filling of copper sulfate deposits. They are used in PCB through-hole plating, IC substrate plating and semiconductor RDL (redistribution layer) copper plating. Whether model 3900LT on this page is a brightener, leveler or complete additive set, and its dosage, should be confirmed with the supplier’s TDS / SDS; the description of three components, RDL and TSV below is general information on acid copper additives and does not represent this product’s specification.
A copper plating brightener is not a single compound but a three-component organic additive system. The brightener (sulfur-containing molecules such as SPS / MPSA) accelerates deposition and produces a bright surface; the leveler (nitrogen-containing molecules) suppresses excess deposition on high points to level the deposit; the carrier (PEG / PPG polymers) controls the overall deposition rate. Together they produce the bright, flat, ductile copper deposits electronics manufacturing requires.
A JIAHON affiliated company supplies customers throughout Taiwan. SDS, CVS calibration curves and process compatibility reports are available on request.
Specifications
| Item | Details |
|---|---|
| Product type | Brightener for acid copper sulfate plating (3900LT on this page; composition and dosage per supplier TDS / SDS) |
| System components | (1) Brightener (SPS / MPSA sulfur-containing molecules) + (2) Leveler (nitrogen-containing molecules) + (3) Carrier / suppressor (PEG / PPG polymers) |
| Appearance | Colorless to pale yellow clear liquid |
| Typical dosage | 5–20 mL / L of bath (depends on formulation and process, case by case) |
| Bath | Acid copper sulfate (CuSO₄ + H₂SO₄ + chloride + additive system) |
| PCB processes | Through-hole plating (aspect ratio 5:1 and above), double-sided / multilayer boards, HDI microvia filling |
| Semiconductor processes | IC substrate BUM (build-up multilayer), RDL copper plating (2–5 µm lines), TSV copper filling |
| Storage | Away from light, 15–25°C, sealed; use within 6–12 months of opening |
| Monitoring | CVS (cyclic voltammetric stripping) or HPLC analysis; replenish according to results |
| Packing | 1 L / 5 L / 20 L PE drums (UN-marked transport containers) |
| SDS / compliance | SDS, RoHS / REACH declarations, GHS hazard labels |
Values are general industry ranges for acid copper additives; actual formulation and dosage must be evaluated by small-scale tests based on bath parameters (copper concentration, acidity, temperature, agitation, anode type), process node and part specification, case by case.
Applications
- PCB through-hole plating: double-sided and multilayer boards with aspect ratios of 5:1 and above need strong throwing power for even copper in the holes; formulations emphasize carrier and leveler to control deposition in deep holes.
- IC substrate / HDI microvia filling: microvias (50–100 µm diameter, 60–100 µm deep) must be completely filled without voids; formulations strengthen the brightener for bottom-up filling.
- Semiconductor RDL plating: in wafer-level packaging, RDL copper lines of 2–5 µm need very flat, low-stress deposits; formulations emphasize leveling and stress control.
- TSV copper filling: TSVs in 3D IC packaging are 5–20 µm in diameter and can exceed 100 µm deep; special super-filling formulations fill the via bottom completely with a flat surface.
How to choose by process
| Process | Key indicator | Formulation focus | Typical dosage |
|---|---|---|---|
| PCB double-sided / multilayer | Through-hole uniformity, ductility | Strong carrier / medium leveler | 10–15 mL/L |
| HDI microvia filling | Bottom-up deposition | Strong brightener / strong leveler | 8–12 mL/L |
| IC substrate BUM | Void-free vias, flat surface | Balanced formulation | 10–15 mL/L |
| Semiconductor RDL | Uniform line width, low stress | Strong leveler / weak brightener | 5–10 mL/L |
| TSV copper filling | Super-filling, void-free deep vias | Special super-filling formulation | Custom evaluation |
The three components
| Component | Typical molecules | Main role | Too much / too little |
|---|---|---|---|
| Brightener / accelerator | SPS (3,3′-dithiodipropane sulfonic acid), MPSA | Accelerates deposition, bright surface, bottom-up filling | Too much: high stress, cracking; too little: dull |
| Leveler | JGB, SH-110, nitrogen-containing quaternary ammonium compounds | Suppresses deposition on high points, deep-hole filling, flat surface | Too much: deep holes not filled; too little: rough surface |
| Carrier / suppressor | PEG 4000, PPG, EO/PO copolymers | Covers the cathode surface, controls overall rate | Too much: slow deposition; too little: surface particles |
| Auxiliary: chloride | HCl or NaCl | Helps brightener adsorption (30–80 ppm) | Too much: burnt edges; too little: brightener ineffective |
Values are general experience; the manufacturer’s specifications and actual conditions apply.
A single accelerator would speed up deposition everywhere, making high points higher and low points lower. The leveler adsorbs preferentially on high points to suppress deposition, the carrier controls the overall rate, and the brightener accelerates in recesses not covered by the leveler — together giving bottom-up filling of deep holes with a flat surface.
Dosing control: why not just top up on a schedule
The three components are consumed at different rates — the brightener usually fastest, the leveler medium and the carrier slowest. Topping up to the initial amount on a schedule leads to excess brightener (high stress, roughness) or too little leveler (unfilled holes).
- CVS (cyclic voltammetric stripping): measures suppressor / carrier and other additive concentrations by adding the sample to a standard bath, running a voltammetric scan and calculating concentration from the stripping charge. Advanced lines use inline CVS with automatic dosing, sampling every 30 minutes to 4 hours (general experience).
- HPLC: measures the nitrogen-containing leveler more precisely but needs a laboratory and 30–60 minutes per sample. Smaller plants use Hull cell panels and visual comparison as a simple alternative.
Plating management tips
- Signs of bath aging: haze, streaks, burnt corners on Hull cell panels, poorer via filling, and rising dosage with little effect all indicate accumulating breakdown products. Carbon-treat every 6–12 months (case by case) and replace the bath every 2–3 years.
- Storage temperature: avoid sunlight and heat (above 40°C accelerates decomposition); a whole drum can lose effectiveness unopened if stored too hot.
- Safety and wastewater: contains sulfur- and nitrogen-containing organic compounds; rinse skin with water immediately after contact, and wear goggles and chemical-resistant gloves. Plating wastewater must be neutralized, flocculated, settled and treated with activated carbon before discharge, according to applicable regulations; in Taiwan, the Water Pollution Control Act applies.
- Changing suppliers: different suppliers’ additives may compete for adsorption sites and cause deposit defects. Do not switch directly — carbon-treat the bath to remove the old system first. Additive changeover is a major process change; the full sequence typically takes 3–6 months (case by case): lab-scale Hull cell (1–2 weeks) → pilot plating (2–4 weeks) → mass production qualification (4–8 weeks) → production.
When you request a quote, please tell us: bath type, process (PCB / HDI / IC substrate / RDL / TSV), current additive system and quantity.
Email us for a quote: [email protected]