Our unique post-treatment designed to mitigate corrosion whisker formation in tin surfaces
Effective corrosion protection
For tin-plated surface finishes on IC outer leads
Effective whisker mitigation
Successfully mitigates the formation of whiskers within heat and humidity
Excellent solderability after hot and humid storage
- Effective corrosion protection for tin-plated surface finishes on IC outer leads
- Successfully mitigates whisker formation within heat and humidity to comply with the iNEMI / Jedec storage conditions (4,000 h at 55 °C / 85% RH)
- Prevents tarnishing within hot and humid storage conditions
- Excellent wettability and solderability after steam aging and pressure cooker test conditions
- Protectostan® LF coating is not affected by the postbaking operation (1 h at 150 °C)
- According to TOF-SIMS, Protectostan® LF2 can withstand multiple reflow cycles
- Protectostan® LF2 post-dip is followed by rinsing and drying. In production, it can also be used as either a neutralization or rinse stage and is thus easily integrated into existing systems
- Can be applied to all types of tin surfaces
A unique post-treatment to mitigate corrosion whisker formation
Protectostan® LF2 is a slightly acidic post-treatment process developed especially for tin and tin alloy surfaces. It was designed to prevent tarnishing during storage – which can lead to solderability problems later on – and to mitigate corrosion whisker.
Protectostan® LF2 reduces the detrimental oxidizing effects of exposed copper to adjacent tin surfaces, effectively mitigating the formation of tin whiskers during heat / humidity storage. The product has also been tested according to iNEMI/JEDEC specifications with different package types of differing leadframe alloy base materials.
What inspires us
Why we developed Protectostan® LF2
The propensity of pure matt tin layers to whisker has become a major concern in terms of implementing this technology as a lead-free solderable finish for IC assembly.
Protectostan® LF2 reduces the detrimental oxidizing effects of exposed copper to adjacent tin surfaces, effectively mitigating the formation of tin whiskers during heat / humidity storage.
Our extensive corrosion and whisker investigations
We carried out extensive studies on the influential parameters for whisker formation.
Our studies illustrate the influence of the neutralizing post-treatment (post dip A) on corrosion through a reduction in the formation and length of corrosion whiskers – a result which encouraged us to develop Protectostan® LF. All tests were carried out under production conditions.