The SEMI Investment Act expands a federal tax credit for advanced manufacturing to include companies that produce materials used to make semiconductors and semiconductor manufacturing equipment, not just the semiconductors and equipment themselves. This change is intended to strengthen the entire supply chain for semiconductor production by incentivizing investment in materials manufacturing facilities. The bill amends the Internal Revenue Code to broaden the definition of what qualifies as an "advanced manufacturing facility" eligible for the investment credit. The legislation is effective retroactively as of the CHIPS Act of 2022, meaning companies that may have already made qualifying investments could potentially benefit from the expanded credit. The bill was introduced in December 2024 and referred to the Senate Finance Committee for consideration.