Your One-Stop Immersion Silver PCB Manufacturer

Your Best Immersion Silver PCB Supplier

Are you searching for the most trustworthy manufacturer of immersion silver PCB? Your search is over. PCBMay will have your back if you need immersion silver PCB and other PCB assembly. We are proud to offer the latest immersion silver PCB solutions for your business. All our products are affordably priced.

PCBMay produces different kinds of immersion silver PCB. You can choose from electronics immersion silver PCB, green solder mask immersion silver PCB, immersion silver PCB with high TG180 material, and so on. You can find this solution usually in medical devices, military devices, or mobile gadgets.

Throughout the years in the industry, we gained full capacity to manufacture immersion silver PCB and other PCB solutions. We designed them with exceptional features and quality. We are developing immersion silver PCBs using our advanced technology manufacturing system.

The immersion silver finishes to a PCB are applied directly over the copper. The material has 5 micro inches to 12 micro inches standard thickness and has the competence to last for at least a year.

More features of the PCBMay immersion silver PCB are;

• Environment friendly and ROHS compliant finish
• Allows solder to spread accurately on its surface
• It has better resistance to environmental aging
• It has the capability to get through multiple reflows
• Safe from black-pad interfacial fracture phenomenon
• It has better flatness, solder joint strength, and more electrical properties

All these beneficial features make our immersion silver PCB an ideal choice for everyone. It also makes the solution perfect for automobiles, communication systems, and computer peripherals. Always choose PCBMay to custom your immersion silver PCB. We can guarantee to help you build a better business with our full support.

For more information or any queries related to PCB assembly and design, you can contact our professionals. We are 24/7 active online for you!

Immersion Silver PCB: The Ultimate FAQ Guide

This is a complete guide to help you understand immersion silver PCBs. Whether you want to learn more about immersion silver PCBs or you want accurate information about these PCBs to help you make a well-informed purchase decision, this guide will be super helpful to you.

This guide will help you understand what immersion silver PCB means, their advantages and disadvantages, the processes involved in their production and assembling.

We will further dive into the factors that determine the choice of PCB surface finish, some of the problems associated with using these PCBs and how you can solve them, proper ways to handle and store these PCBs, and many more.

Let’s dive in

Immersion silver PCB.

What Is Immersion Silver PCB?

Immersion silver PCB is a type of PCB that is coated with silver to provide a quality surface finish. The PCB is immersed in a silver solution such that layers of silver are formed on the copper surface of the board.

What Is Immersion Silver Finished?

Immersion silver finish is a PCB surface finished technique whereby a thin layer of silver is applied to the copper layer of the PCB. Immersion silver provides massive protection to the PCB layer and prevents corrosion. It as well offers the PCB a smooth and flat surface, making it easy to work on. It makes assembling the board’s circuit component super easy and simple.

Immersion silver finish

Silver’s excellent electrical conductivity makes it ideal for PCB finish. The good electrical conductivity of silver makes it suitable for high-speed PCB applications.

Wondering how immersion silver finish is done? This is it. This is done by immersing your PCB in a silver ions solution. This results in a flat silver layer forming on the copper layer of the Pcb. The flat silver layer formed on the copper layer of the PCB Protects it from corrosion. What’s more? It makes soldering on the board easy. It makes the PCB last long.

Immersion silver PCB

What Does Immersion Silver PCB Tarnish Mean?

This is a situation whereby the original colour of the immersion silver PCB is depleted with time as a result of continuous exposure to air. This happens when the silver layer reacts with Sulphur and Chlorine to create Ag-S and Ag-Cl compounds on the board’s surface. This condition can also reduce the solderability performance of the board’s surface.

A sure way to prevent silver PCB tarnish is to coat the board with an anti-tarnish agent after the immersion silver. Another effective way is to store the PCB in a place that has no air and Sulphur.

What Processes Are Involved In Immersion Silver PCB?

Immersion silver PCB involves many processes. Let’s look at these processes below:

Clean the board

First, you have to clean the board. This helps to take away contaminants like dust, fingerprints. You need to wet the board surface so that no air gets trapped in the

Micro-etching

Here, minor changes are done to the copper surface of the board. This is done by bathing the board in a sulfuric acid solution.

Pre-dip the board

Pre-dipping is done to prepare the surface of the board for silver coating. The board is immersed in acid to achieve this purpose. Another reason for immersing the board in acid is to limit the possibility of oxidation.

Immersion of the board into silver

At this stage, the silver layer is formed on the copper layer of the PCB. You can do this by immersing the board in a silver solution. The copper layer reacts with the silver ions to reduce the copper layer. It is important to note that this step should be done with care and should be slow so that a uniform, smooth and consistent silver layer will be formed.

Post-dip the board.

The last step in the immersion silver PCB process is post-dipping. This process involves coating the board with an antioxidant organic compound. This is done to avoid the removal of the silver coating and oxidation. This helps to maintain the silver coating.

Immersion silver PCB process

What Advantages Can You Get From Immersion Silver PCBs?

Using an immersion silver finish for your PCB offers you tremendous advantages. Let’s have a look at some of the benefits you can get from immersion silver PCBs:

• Immersion silver finish is safe to use in the environment since they comply with RoHs standards. They are safer than immersion tin.
• They offer you a superb surface level that makes working on your PCB easy.
• They are easy to use compared with organic soldering preservatives.
• They offer efficient soldering of PCB components by providing excellent soldering surfaces
• They are cheaper than Electrode-Nickel Immersion Gold.
• It allows you to do rework on immersion silver PCB.
• Their excellent electrical conductivity makes them suitable for high-frequency devices.
• They are not affected by the blad pad effect.

Advantages of immersion silver PCB

What Are The Disadvantages of Immersion Silver PCB?

Despite the great benefits immersion silver PCBs offer, they have some shortfalls. Below are some of them:

• Preserving the integrity of this type of finish demands the use of a special type of packaging.
• It can be challenging to handle PCBs having this finish because they are sensitive. It is better to wear sulfur-free gloves when handling immersion silver PCBs.
• They are not suitable for peelable masks.
• They are susceptible to develop whiskers in the presence of electrical fields.
• Immersion silver PCB finish easily tarnishes when exposed to air.
• They possess limited operating windows between phases of the assembling process

How Can You Make Immersion Silver PCB Lasts Long Before It is Used?

The best way to make the immersion silver PCBs last before their usage is to store them in an air-tight and Sulphur-free environment. In addition, you need to do a solderability test on the board after some time. Generally, these PCBs have a 12-month shelf life.

 What Is The Comparison Between Immersion Silver PCB and Immersion Gold PCB?

In this section, we will compare immersion silver PCBs with immersion gold PCBs. Below are some unique comparisons between them.

1. Immersion silver PCBs are comparatively cheaper than immersion gold. As you may know, gold costs more than silver and this makes immersion gold expensive.
2. Immersion silver PCB is ideal for making high-frequency equipment and devices due to its high electrical conductivity.
3. Immersion silver PCBs don’t form black pads on their surface. On the other hand, immersion gold can have them.
4. Immersion gold PCB lasts long than immersion silver PCB
5. Immersion gold PCB prevents oxidation while immersion silver is susceptible to oxidation.

Immersion silver PCB

What Is The Best Way To Handle and Store Immersion Silver Finish Products?

You need to take various precautionary measures to ensure effective storage and handling of immersion silver PCB. These precautions should be taken due to the highly sensitive nature of immersion silver PCB. Below are some best ways to handle and store these PCBs:

1. Store immersion silver PCBs in air-tight and Sulphur free locations to prevent tarnishing of the board’s surface.
2. Always wear gloves when handling immersion silver boards. Touching these boards with your bare hands would tarnish them and cause soldering problems.
3. Use water washes with a PH greater than 6.0 to clean these boards. Don’t use acid cleaners on these types of boards.
4. Conduct a solderability test on the board when you store it for a long time. This will help you know if the board still possesses its soldering ability before assembling circuit parts.
5. Store the boards in a dry environment for about 6- months.
6. Ensure you immediately assemble the components on the board after unpacking them.
7. You need to use the proper temperature when heating the PCB to reduce its stress or drain water from it.

Immersion gold PCB.

How Can You Assemble Immersion Silver PCB?

Let’s dive into the various processes through which you can assemble immersion silver PCB.

Solder Paste Stenciling

The first step of the assembling process is to apply solder to the necessary parts of the board. How? You need to cover the board with a stencil so that you can apply the solder at portions that you will mount the components.

Before doing this, you need to fix the board and the stencil in a mechanical fixture. You then apply the solder with an applicator. This ensures the solder is uniformly distributed on the board.

Placement Components

Use a robot or mounting machine to pick and place the components on to the board’s solder locations.

Soldering Reflow

The next step of the immersion silver PCB assembling process is soldering reflow.

You do this to solidify the solder paste so the joints between the board and the assembled components become strong. The boards are passed through a reflow oven to heat the paste.

From the oven, you need to pass the assembled board through a cooler to solidify the paste. This heating and cooling of the paste create solid joints on the board.

Immersion silver PCB design

Quality Control

At this stage, you inspect the PCB to find and rectify any existing errors or connectivity issues. You can use various inspection methods such as manual Checks, X-ray Inspection, Automatic Optical Inspection, etc.

Through-hole component inspection

For boards that have through-hole parts, you need to install them here. This can be done through manual soldering or wave soldering, considering the board’s complexity level.

Last Inspection and Functionality Test

The final step of the process is to inspect and test the assembled immersion PCB board. You need to test the board to be sure it functions as required.

Testing immersion silver PCB

What Is The Suitable Thickness For Immersion Silver Surface Finish?

The immersion silver surface finish has a thickness ranging between 1.6 um. This makes this type of PCB finish about a hundred times thinner than electroplated silver.

What Are The Common Challenges Associated With Using Immersion Silver Finish? How Can They Be Solved?

Using an immersion silver finish for PCB comes with some challenges. Let us look at some of them and how they can be addressed.

Tarnish

The major challenge with immersion silver finish PCBs is that they can tarnish when exposed to air. When PCBs with this type of finish is exposed to air, they react with Sulphur and chlorine to form AgS Agcl. This formation causes the PCBs to corrode and lose their original colour.

You can solve this problem by storing immersion silver PCBs in airtight and sulphur-free packages. Anytime you open the package storing these PCBs, close it as early as possible and reseal it. Using an anti-tarnish bath for these PCBs after the silver coating is a great way to avoid tarnishing the PCB.

Galvanic Effect

The galvanic effect is a condition that arises during the immersion silver stage. This happens between the cracks formed on the solder mask and the copper surface of the board. The silver ions released during the silver immersion process encounter some restrictions leading to the corrosion of copper.

To avert this condition, you need to do a proper copper surface treatment at the micro-etching stage. This will ultimately help you to achieve a smooth and uniform immersion silver surface. 

Silver Whiskers

Another problem associated with this type of finish is silver whiskers. This situation occurs when you leave your PCB open to high hydrogen sulfide and humidity.

To avoid this problem, it is advisable to apply a conformal coating to the top later of the silver layer.

Why Should You Wear Sulphur-free Gloves Before Touching Immersion Silver Surfaces?

The super-sensitive nature of immersion silver PCB requires that you wear gloves when handling them. Why? This is crucial because sweat and dirt from the hands can pollute the silver layer. This becomes worse when you touch the board with oily hands.

Handling these boards with bare hands can deform the board’s silver layer, tarnish it and even increase its thickness. It becomes difficult to solder components on such deformed surfaces.

What Does Immersion Silver PCB RoHS Finish Mean?

Immersion silver PCB RoHS finish refers to a surface finish technique that follows the Restriction of Hazardous Substances RoHS standards. RoHS regulations ensure the use of no harmful substances in various electronic and electric equipment. Immersion silver PCB finish is environmentally friendly since no harmful compound like lead is used.

What Factors Do You Need To Consider When Choosing PCB Surface Finish?

To make the right choice for your PCB finish, you need to make several well-thought considerations. Let’s have a look at some of them:

• You need to consider the board’s compliance with RoHS standards
• You should check the cost involved in the process
• Consider the shelf life of the PCB
• You need to look at the working environment of the board.
• You should consider the possibility of the high-frequency application of the board.
• Consider the number of boards you need to make.
• You should consider the board’s shock and fall resistance.

Why Does Immersion Silver Board Oxidize?

 Many factors account for the reason why immersion silver PCBs oxidize. Below are some of them:

These types of PCBs are easily oxidized when they come into contact with air. When you use poor packages for the boards, air can easily enter and cause oxidation of the boards.

Another major cause of oxidation is when the boards are stored in an environment that has a high temperature, massive pollution, and high humidity.

What Does Immersion PCB Baking Mean?

Exposing immersion silver boards to moisture leads to several problems like oxidation, corrosion, etc. PCB baking is an effective way to drive out moisture and stress from the PCB.

A specialized oven is used to bake the board under-regulated environment to drive out moisture and stress from the board. Only use ovens designed for this purpose so that the boards are not destroyed.

How Do You Import Immersion Silver PCBs from China?

Below are the processes you can follow to import immersion silver PCBs from China.

Choose a reliable manufacturer

Before you can import immersion silver PCBs, you need to first choose a reliable Chinese supplier. Go in for an experienced and professional supplier with good track record.

After choosing the supplier, you browse through their website and select your desired PCBs from their product catalogue. After this, you can contact them on their website and inform them of the type of board you want.

Sign a contract with the supplier

Once you settle on your favorite PCB manufacturer, you need to sign a contract with them.

Some of the vital information that the contract should include is the specification of the board, the quantity, warranty, after-sale service, mode of payment, etc.

Determine your import duty

To Import immersion silver PCB from China, you need to pay some importation fee.  This fee varies from country to country, so you need to find out from your country’s authorities.

Receive Vital Import Documents.

Here, you need to collect some vital information from the supplier to help you receive the PCBs once it gets to your country.

You need documents such as the packing list, sales contract, and bill of lading documents.

Obtain Delivery Codes

Some countries require you to have delivery codes to enable you to receive your boards at the port. You can get this information from your country’s authorities.

How Do You Choose a Reliable Immersion Silver PCB Supplier?

Getting a reliable immersion silver PCB supplier can be challenging because there are several manufacturers on the market who don’t meet standard industry requirements. Buying from such manufacturers may lead to a loss on your side since they don’t produce quality boards.

To be on the safer side, follow the tips below to help you choose a good manufacturer.

Experience

The manufacturer should have massive experience in PCB board production. The manufacturer should have at least 10 years of experience in PCB manufacturing. They should have an experienced workforce who have the expertise to produce quality boards.

After-sales services

You need to go in for a 12 layer PCB manufacturer that offers quality after-sales services like warranty, installation, maintenance, and excellent customer service. The manufacturer should offer at least a 1-year warranty for their board. Warranty is proof of the manufacturer’s confidence in their boards.

Shipping Expertise

The manufacturer should have experience in shipping boards to different parts of the world, especially your locality. This will help avoid some of the challenges associated with shipping or importation. A manufacturer with shipping experience will smoothly process your boards so you receive them safely and on time.

Standard manufacturing process

You should choose a manufacturer whose manufacturing process complies with standard industry processes. They should have PCB certifications and comply with RoHS rules. They should use modern technology and facilities for their operation. This ensures they produce quality PCBs that meet your standard.

Final Thoughts

In this guide, we looked at the meaning of immersion silver PCBs, their advantages and disadvantages, the processes involved in their production and assembling.

We further dived into the factors that determine the choice of PCB surface finish, some of the problems associated with using these PCBs and how you can solve them, proper ways to handle and store these PCBs, and many more.

If you’re looking for high-quality immersion silver PCBs for your projects, look no further than PCBMay. PCBMay is your one-stop immersion silver PCB manufacturer. PCBMay is a leading PCB manufacturer in China with massive experience in the PCB industry. We use best-in-class equipment and industry experts to produce quality and safe boards you can trust. Contact PCBMay now for the best silver immersion PCBs.