4) Which solution is used for electroless copper plating process?
Sulphuric acid and Copper carbonate
Related Quality control - Tests MCQ with Answers
Acid type
Electroless Nickel Plating (ENP) is the deposit of a nickel-alloy coating by chemical reduction – without the electric current that's used in electroplating processes. Acid type of solution is used for electorless nickel plating.
10 to 20 minute
Electroless plating, also known as autocatalytic plating, is a process of depositing a metal or alloy onto a substrate (usually a metal or a non-conductive material) without the use of an external electric current. Unlike electroplating, where an electric current is used to deposit metal ions onto a substrate, electroless plating relies on chemical reactions for metal deposition.
Here is a brief overview of the electroless plating process:
Surface Preparation:
- The substrate is thoroughly cleaned to remove any contaminants, grease, or oxides from its surface. This step is crucial to ensure good adhesion of the plated layer.
Activation:
- The substrate is then activated to facilitate the adsorption of metal ions. Common activation methods include the use of sensitizing agents or sensitizing baths that provide a catalytic surface for the subsequent deposition of metal.
Autocatalytic Plating:
- The activated substrate is immersed in an electroless plating bath containing metal ions, reducing agents, and other chemical additives. The metal ions are reduced on the catalytic surface of the substrate, leading to the deposition of a metal layer.
Chemical Reactions:
- The reduction of metal ions is typically achieved through chemical reactions involving a reducing agent. Common reducing agents include formaldehyde, hypophosphite, or borohydride, depending on the specific metal being deposited.
Control of Plating Thickness:
- The plating process continues until the desired thickness of the metal layer is achieved. The process is typically monitored and controlled to ensure uniform deposition.
Post-Treatment:
- After plating, the substrate may undergo post-treatment processes such as rinsing, drying, and sometimes additional treatments to enhance the properties of the plated layer.
Electroless plating is often used in various industries for applications where uniform coating thickness, corrosion resistance, and complex part geometries are important. It is particularly advantageous for plating non-conductive materials, such as plastics or ceramics, where traditional electroplating may be challenging.
Common metals deposited through electroless plating include nickel, copper, gold, and palladium. The choice of plating material depends on the specific application and the desired properties of the plated layer.