Samsung Foundry's 4nm yield doubles from 2022 to 70%

Back in early 2022 reports were surfacing that Samsung Foundry's yield on 4nm production was only 35% That means that only 35% of the dies produced on a silicon wafer passed Quality Control and were good enough to ship. At the time, TSMC's yield on its 4nm node was believed to be 70%. Since the chip designer is responsible for paying for defective chips, Qualcomm decided to move production of the Snapdragon 8 Gen 1 to TSMC where it became the Snapdragon 8+ Gen 1.

The latest report from Chosun says that during October, Samsung Foundry's yield on 4nm production was 70% generating some new business for the foundry. For example, AMD's new 'Zen 5c' server chips, known by the codename Prometheus, started production Wednesday using Samsung Foundry's 4nm node and TSMC's 3nm node. Traditionally, AMD has had its chips built by TSMC but is looking to work with both of the world's top two foundries.

As to why AMD is using both TSMC and Samsung Foundry simultaneously, it is believed that the company is planning to offer high-end and entry-level versions of the chip; in this scenario, TSMC is building the high-end silicon using its 3nm process node while Samsung will manufacture the entry-level chip using its 4nm node. Another possibility is that AMD considers TSMC's N3 node as being similar to Samsung's 4nm node in terms of performance and that AMD sees TSMC's 3nm version of its 'Zen 5c' server chip as being the same as the 4nm version being built by Samsung.

If Samsung Foundry can impress AMD with its 4nm version of the server chips, researchers believe that it could lead to Samsung Foundry receiving an order from AMD based on its 3nm Gate All Around (GAA) node. With Gate All Around transistors, which Samsung is using at 3nm and TSMC isn't until it starts manufacturing chips at 2nm, vertically placed horizontal nanosheets are used to contact the channel on all four sides reducing current leaks and increasing the drive current leading to improved chip performance.

Researcher Kim Yang-paeng, who works at the Korea Institute for Industrial Economics and Trade, said, "If Samsung successfully wins an order for AMD’s 4-nano chips this time, it will open the door to transactions in the 'big chip' field for servers, where Samsung was weak. This will be an opportunity for Samsung Foundry’s influence to grow."

Right now, TSMC's N3B process node is used to produce the 3nm A17 Pro SoC used on the iPhone 15 Pro and iPhone 15 Pro Max. No other smartphone will use a 3nm chip this year although that is expected to change in 2024. Additionally, next year's A18 Pro could end up on all four iPhone 16 models and will be made using TSMC's N3E node. Apple has a sweetheart deal from TSMC as the foundry is eating the costs for defective chips this year only, saving millions of dollars for its largest customer.

TSMC's 3nm capacity is such that it cannot handle orders for the entire industry and it raised its prices for 3nm production. This has let some fabless chipmakers (like Apple, fabless chipmakers design their own chips but count on a contract foundry to manufacture them) to turn to Samsung Foundry. With the latter's yield on 4nm and 3nm GAA at 70%, Samsung Foundry is believed to be close to winning an order from a large European customer.

Samsung's own Exynos 2400 application processor (AP), expected to power the Galaxy S24 and Galaxy S24+ in all markets outside of the U.S. and China, has reportedly gone into production by Samsung Foundry using its 4nm node. With its deca-core design, Samsung has high hopes for the homegrown AP for next year. Samsung is reportedly going to use new packaging technology that can improve the thermals and the performance of its chipset.

If Samsung Foundry's yields remain high or improve, it can only help Samsung Foundry win more business.