Instead, they design chips and then they rely on other companies—most importantly, the Taiwan Semiconductor Manufacturing Company (TSMC)—to produce those chips for them.
Nvidia, AMD, Qualcomm, Broadcom, Alphabet, Microsoft, Amazon, Tesla, Cerebras, SambaNova, Groq: none of these companies build their own chips. Instead, they design chips and then they rely on other companies—most importantly, the Taiwan Semiconductor Manufacturing Company (TSMC)—to produce those chips for them.