One Dutch company controls the machine behind every leading-edge processor on Earth. Substrate wants to route around it using X-rays instead of extreme ultraviolet light. Here is what stands up, what remains a pitch, and why chipmakers from Taiwan to Dholera are watching.

China faces three specific barriers as it aims to produce key chipmaking equipment. Monitoring progress in these areas would help Western countries make better chip and AI policy.

One Dutch company controls the machine behind every leading-edge processor on Earth. Substrate wants to route around it using X-rays instead of extreme ultraviolet light. Here is…