Surface Finishes

A two-stage process which extends circuit often referred to as ENIG plating, this is a two-stage process perfectly suited for manufacturing various styles of Printed Circuit Board (PCB) within aerospace, electronics and medical industries.

The same process as ENIG plating but Electroless Nickel, Electroless Palladium and Immersion Gold (ENEPIG) follows the same process as ENIG plating (see above) but with the introduction of a third metallic layer consisting of Palladium (Pd). While the cost is higher than regular ENIG plating, it provides a thinner coat for finer pitch, and prevention of nickel corrosion sometimes associated with complicated boards that require both soldering and wire-bonding. Also, the ENEPIG process enables RoHS compliant soldering.

Gold Electroplating is a chemical process which applies a thin layer of gold over a base metal by applying an electric current to an object within a bath of gold solution. Unlike soft gold plating (see below), additional composites are introduced to the gold to create a harder gold alloy. This, in combination with the use of nickel as a substrate, creates properties best suited to high-friction applications to prevent tarnishing through wear. For example, pin connectors on a PCB.

At EuroTech, we carry out our gold plating in-house. This allows finite control over the design, thickness and quality. Typical values for hard gold plating over nickel include:

Ni 1.0µm – 6.0µm
Au 1.0µm – 3.0µm

Electroless soft gold plating is a single Gold Electroless is a single-stage chemical process which applies a thin layer of gold over a copper base metal by applying chemical displacement. Unlike hard gold plating (see above), The gold remains ‘pure’ to retain malleability for improved solderability. This creates properties best suited to low-friction, enclosed applications which are not subject to wear.

​Immersion Silver plating is a process which extends the durability of each PCB, following the same methods as our immersion gold. It creates a protective layer of silver or alloy over the outermost surface of the PCB to protect copper elements from oxidisation, offering superior solder joint strength. 

Immersion Tin is another Lead-free surface finish. Best suited for press-pin connectors, Immersion Tin (ISn) is another of our chemical displacement processes deemed better for the environment as a Lead-free option. It is not suited for all applications due to a limited shelf life

​Lead-Free Hot Air Solder Leveling (HASL) follows the same process as leaded HASL with the exception of the use of lead. A lead-free molten tin-compound is applied as a protective surface finish to the outer layer of the PCB. Excess metal is then dispersed and cooled with heated air.

This process is carried out in our Factory.

RoHS compliant soldering is available for some niche applications (eg. aerospace, military and medical industries)
10µm – 25µm

​Lead-Free Hot Air Solder Leveling (HASL) follows the same process as leaded HASL with the exception of the use of lead. A lead-free molten tin-compound is applied as a protective surface finish to the outer layer of the PCB. Excess metal is then dispersed and cooled with heated air.

This process is carried out in our Factory.

RoHS compliant soldering is available for some niche applications (eg. aerospace, military and medical industries)
10µm – 25µm

Organic Solderability Preservative (OSP) is a way of coating the Cu areas of a PCB preventing oxidation of the Cu.  It uses an organic solution that bonds to the Cu element to protect the Cu until the soldering stages. Today’s OSP offers 12 month shelf life with 3 x multiple soldering capability. With this process the component interconnection is directly with the Cu surface of the PCB offering highest reliability of joint strengths.

We carry out this process in-house at our factory.

Entek / RoHS Compliant Soldering
0.2µm

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​Silver ink is a process which uses developed ink comprised of silver acetate. This is dissolved in ammonia to give a clear solution which is used to form the trace pattern, mainly for use with flexible substrates.

These PCB’s are common within technology markets where flexible screens or antennae are used.