- 25 Aug, 2025
The ESD Challenge in Semiconductor Packaging
In advanced packaging processes such as Ball Grid Array (BGA), Chip Scale Package (CSP), and flip chip assembly, solder ball templates play a critical role in ensuring accurate ball placement. These templates, often manufactured from anodized aluminum, offer mechanical durability and dimensional stability. However, anodized aluminum has one serious limitation: its surface resistivity ranges from 10¹¹ to 10¹³ Ω·cm, making it highly insulating.
This leads to static charge buildup during repeated solder ball loading and handling. Without controlled dissipation, charges can suddenly discharge, causing:
- Misalignment of solder balls
- Clustering or sticking within fine pitch apertures
- ESD damage to wafers or substrates
- Reduced yield and hidden reliability issues
Why Conventional Solutions Fall Short
Temporary anti-static sprays and films degrade quickly, peel under wear, and risk contamination. Traditional hard coatings improve durability but lack tunable resistivity, leaving surfaces either too insulating or overly conductive. Neither extreme supports stable solder ball transfer in high-volume semiconductor production.
What the industry needs is a thin film static dissipative coating that combines durability, tunable resistivity, cleanroom compatibility, and friction control.
NTI Nanofilm’s ASD TAC ON®: Static Control Through Thin Film Engineering
TAC ON®, part of NTI Nanofilm’s ASD coating portfolio, is engineered to address these challenges directly. Deposited using Filtered Cathodic Vacuum Arc (FCVA), TAC ON® forms an ultra-dense ta-C multilayer that adheres strongly to anodized aluminium without altering dimensional precision.
Key Advantages for Solder Ball Templates:
- Tunable resistivity: Adjustable within 10⁵–10⁹ Ω/sq, ensuring controlled charge bleed while avoiding full conductivity.
- Wear resistant ESD finish: Protects apertures and template edges from abrasion across repeated solder ball cycles.
- Low coefficient of friction: Facilitates smooth solder ball release, minimizing clustering in BGA and CSP templates.
- Cleanroom compliance: Vacuum-deposited thin film, free of solvents and particulates, fully compatible with semiconductor production lines.
Benefits for Semiconductor Manufacturing
By applying ASD TAC ON® to anodized aluminum templates, manufacturers achieve:
- Improved yield through reduced solder ball misplacement and static-induced defects
- Enhanced ESD protection, preventing sudden discharges that damage devices
- Extended tool life, as the coating resists wear and cleaning abrasion
- Process stability, maintaining resistivity and performance over long production runs
- Lower operational costs, thanks to fewer rework cycles and longer template lifetimes
TAC ON® Feature Comparison
Feature | Standard Anodized Aluminum | Anodized with TAC ON® |
Surface Resistivity | 10¹¹–10¹³ Ω·cm | Tunable 10⁵–10⁹ Ω/sq |
ESD Risk | High: charge accumulates unpredictably | Low: controlled, consistent discharge |
Process | Electrochemical anodizing | FCVA thin film coating |
Wear Resistance | High, but edges wear with repeated cycles | 30% higher wear resistance, protects apertures and edges |
Friction & Release | Moderate, ball sticking more likely | Up to 20% smoother solder ball release |
Cleanroom Compatibility | High, stable oxide layer, but static risk remains | High, solvent-free, ultra-low particle, ESD-safe |
Conclusion: Precision with ESD Safety
For solder ball placement templates in BGA, CSP, and flip chip packaging, anodized aluminum provides mechanical strength but introduces ESD risks. NTI Nanofilm’s ASD TAC ON® thin film coating overcomes this limitation by combining tunable resistivity, wear resistance, and cleanroom-compatible surface engineering.
The result is ESD safe semiconductor tooling that enhances reliability, prolongs tool life, and supports high-yield packaging operations.