SW - 2X
Electroless Nickel Plating Solution for Silicon Wafers
The SW – 2X is an electroless nickel plating
solution with low ammonia odor designed specifically for silicon wafers.
1. Product Features:
a.Low-phosphor nickel-phosphor film forms an alloy of 96-98% of Ni and approximately 2% P4. It enhances the performance quality of electronic components.
b. The nickel-plating solution is very stable; the films coating deposited on P and N sides of electronic components are uniform in thickness.
c. Deposited film creates excellent brightness and consistency on electronic components.
d. PH 8.5, low ammonia odor improves working environment.
e. Thicknesses of coating can be easily managed by controlling the nickel-plating time.
2. How to Use the Product:
a. Making the Solution bath: Combine 500 cc/L of SW-2X, 365 cc/L of pure water (or distilled water) and 135 cc/L of 28% (first grade) ammonium hydroxide to make up a 1 L bath solution. Adjust the pH to 8.5 and stir well to mix. Use a filtering funnel and paper filter to filter the solution before the plating process.
b. Temperature:：90°C ( 85°~ 95°）
c. PH：8.5 ( 8.4~8.6 )
d. Speed of nickel plating:5~7μm/hr at90°C
e. Capability of nickel plating: 10~30μm xdm2/L
3. How to Manage Remaining Plating Solution:
Ammonium hydroxide will dissipate over time. To reuse the plating solution, it is important to add additional ammonium hydroxide to adjust the pH to 8.5 and the ratio of ammonium hydroxide to 28%. Generally, the ammonium hydroxide dissipates at the rate of approximately 15 cc/L/Hr.
4. Key Functions of the SW-2X
a. Form ohmic contacts on silicon wafers.
b. Form electrodes on ITO surface.
c. Used in diodes, thyristors, transistors of solar cell, etc.
5.Suggested Plating Time
One-time nickel-plating, 45 sec or 1 min. Two times plating, 1 min or 1.5 min. For one-time nickel-plating, the thinner the coating film (under 0.1 m), the better for its Rikure property (however, the thicker, the greater adhesion). For two times plating, the thicker the coating film, the easier it is to weld.
6.Advantages of SW-2X
Ni-Si is formed during sintering. If the Ni-Si layer is too thick, it would cause damages to the junction, and compromise Rikure property. The optimal coating thickness should be under 0.1 μm. With SW-2X, you can achieve the uniformity of thickness on both P and N sides by controlling nickel-plating time. Thickness under 0.1 μm creates the best products quality. While most nickel-plating solution available in market cannot achieve uniformity in thicknesses on P and N sides, resulting poor outcome and quality. The plating time required for using SW-2X is significantly shorter. Therefore, it increases productivity and decreases costs.
7.This product does not contain any lead compounds.