We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is a Solder Mask?

By Geisha A. Legazpi
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A solder mask is a shield to prevent molten lead from sticking to untargeted metals during solder operations. In printed circuit board solder operations, the goal is to form a conductive path between the conductive pad and the component lead. The solder mask ensures that there are no unintended short circuits created in the process.

Printed circuit boards hold the conduct traces and the electronic components in place. The blank printed circuit board is a thin sheet stuck to an insulator board, such as fiberglass or epoxy resin. A printed circuit board is processed first by using an acid mask to define the traces or electrical conductors that will remain when the board is immersed in a copper-dissolving acid, such as ferric chloride, in a process called etching. After etching, the board is cleaned and then printed with both labels and a solder mask or solder resist to expose only the connection points.

Chemical reactions are therefore important for the printed circuit board manufacturing process. A single-sided printed circuit board is first applied with an etching mask that exposes copper laminates that are to be removed. By the action of an acid, the masked portions remain.

After mounting the components on a printed circuit board, it is preheated and ready for soldering. The connections on the underside of the board may undergo a process called wave soldering, where molten lead comes in contact with exposed connection pads that are usually metal-plated copper. If a solder mask was not applied, the long runs of individual traces will get short circuited in the soldering process.

Mass production in electronics manufacturing makes use of solder mask film for preparing boards for soldering. A liquid solder mask is useful for printing the mask using silkscreen or other printing methods. Epoxy-type solder masks may be more resistant than lacquer-type solder masks.

An etched board will look like an insulator sheet with lines, which are patterns of copper conductors. The next step may be solder mask printing. The board can then be drilled to fit any components that need through-holes. For single-sided printed circuit boards, the only choice is to use through-hole components.

Once the components are mounted, the extra leads at the trace side will be cut. The next step is usually wave soldering, which will preheat the board and allow a wave of molten lead to progress through the underside of the printed circuit board. In the process the board is totally soldered in a few seconds, even with hundreds of solder points.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.