Just 10 kilometers off Sejong-si, the administrative capital of South Korea, lies a factory roughly the size of 24 soccer fields. The Sejong Plant, run by Samsung Electro-Mechanics since 1997, is responsible for manufacturing a key component that is used in semiconductors (widely known as chips) - semiconductor package substrates.
Semiconductor package substrates enhance chip performance by transmitting electrical signals between the semiconductor and the main board. It also protects the chip from external shocks.
To make an analogy, the semiconductor is the human brain, and semiconductor package substrates are both the skeleton that protects the brain and the neurons that send signals from the brain to each organ.
Semiconductors have become the modern world's equivalent of oil as they power smartphones, computers, cars, artificial intelligence, and even weapons of war.
As global chip-makers race to develop more advanced chips, the circuits in semiconductor packaging substrates have also become increasingly sophisticated. The global semiconductor packaging substrate market is expected to reach $15.2 billion by 2027, up from $10.6 billion in 2023.
The Sejong Plant is the birthplace of Samsung's substrate business. The company began manufacturing semiconductor package substrates in 1997, marking the end of Japanese-made substrates. Today, the products manufactured on this site account for more than 60 percent of the company's semiconductor packaging substrates sales.
The site focuses on producing semiconductor packaging substrates used in smartphones, namely the Flip Chip Chip Scale Package (FCCSP), which is number one in terms of global market share. The Sejong Plant also makes memory chips for mobile phones, 5G antennas, ARM central processing units (CPUs) for laptops, and semiconductor packaging substrates for cars.
The company unveiled part of the production process on Dec. 2, including circuit imaging, a lamination process that stacks substrates in both directions, and a plating process that requires drilling holes between each layer.
Most of the production takes place inside large machines. Robot arms the size of a grown-up man were picking up substrates and moving them into the clean room, a controlled space that filters pollutants such as dust.
The substrates produced here are usually smaller than the tip of a finger and contain thousands of tiny bumps on which semiconductor chips are placed. If a problem arises in one of the bumps, the entire substrate becomes unusable, which is why the production takes place in a clean room.
"Even a speck of dust thinner than a sheet of paper will result in product failure," said a company spokesperson.
Anyone entering the clean room is required to wear coveralls, vinyl gloves, and indoor shoes, then go through a 10-second shoe shine machine followed by a 10-second air shower. The use of sunscreen and make-up is also prohibited.
The room is equipped with a 24-hour monitoring system that detects the presence of pollutants every 30 seconds and checks the temperature and humidity of the room at all times.
Samsung Electro-Mechanics has the technology to produce high-performance semiconductor package substrates. The circuit lines of the company's substrates are as thin as 3 micrometers (0.001 millimeters), which is one-fortieth the thickness of a single strand of human hair.
To create more circuits within a limited area, the company added more layers - the FCCSP currently produced at the site has up to 20 layers. Even with 20 layers, the thickness of the substrate is less than 2 millimeters.
Samsung will begin producing next-generation semiconductor package substrates next year. The new factory, the company's fifth factory at the site, will manufacture semiconductor package substrates that can support 2.5D packaging, a technology needed for high-performance semiconductors. The new plant is scheduled for completion in May 2024.
This article was originally published on Nov. 5, 2023.