Which type of metal finishing is used in manufacturing of PCBs?

An immersion finishing provides excellent flatness and the use of gold provides a strong solderability. To sum things up, ENIG surface is ideal for bonding, has a strong solderability, provides a flat surface and has a good shelf life.

What is OSP in PCB?

Organic solderability preservative or OSP is a method for coating of printed circuit boards. It uses a water-based organic compound that selectively bonds to copper and protects the copper until soldering. The compounds typically used are from the azole family such as benzotriazoles, imidazoles, benzimidazoles.

What is solder finish?

HASL or HAL (for hot air (solder) leveling) is a type of finish used on printed circuit boards (PCBs). The PCB is typically dipped into a bath of molten solder so that all exposed copper surfaces are covered by solder. Excess solder is removed by passing the PCB between hot air knives.

What is Enepig surface finish?

ENEPIG is a type of surface finish done on copper layer to protect it from oxidation and corrosion in printed circuit boards. This surface finish improves the solderability of copper and is also RoHS compliant.

What is black pad?

Black pad is a term that usually refers to nickel corrosion on electroless nickel and gold immersion (ENIG) surface finishes on PCBs. The defect is not seen as part of normal QC procedures as the immersion gold masks the appearance of the nickel under the gold.

What is ENIG finish PCB?

ENIG is a two layer metallic coating of 2-8 μin Au over 120-240 μin Ni. The gold protects the nickel during storage and also provides the low contact resistance required for the thin gold deposits. ENIG is now arguably the most used finish in the PCB industry due the growth and implementation of the RoHs regulation.

What is via tenting?

Tenting a via refers to covering via with soldermask to enclose or skin over the opening. A via is a hole drilled into the PCB that allows multiple layers on the PCB to be connected to each other. A non-tented via is just a via that is not covered with the soldermask layer.

What is hard gold in PCB?

In PCB gold plating process, hard gold plating is also referred to as a plating alloy. It has been alloyed with other elements which makes it harder, whereas the soft gold plating is pure gold. Plating gold application in PCB manufacturing.

What is the difference between ENIG and Enepig?

ENEPIG is similar to ENIG in both utilize electro-less nickel on top of copper plating; the difference is while ENIG has gold deposited directly on top of nickel, ENEPIG has an additional layer of palladium between the nickel and final gold layer (see below Fig. 1).

Is Enig a Rohs?

ENIG PCB finish is a double layer metallic coating with nickel that acts both as a protective barrier to the copper circuits and a surface on which the components are welded. A layer of gold protects nickel during storage. Enig is Rohs compliant and people tend to use the tersm together.

What is hyper corrosion?

It should be noted that for purposes of this writing, I define hyper-corrosion as a spike or fissure in the nickel deposit evident after immersion gold plating. Finally the root causes of such attack on the base nickel will be presented along with strategies to mitigate these effects.