July 23 (Reuters) - Amkor Technology said on Thursday it had entered a multi-year agreement ‌with Nvidia worth $1.5 billion to expand ‌advanced semiconductor packaging and test capacity in the U.S., as ​the chip industry races to build out AI infrastructure. Shares of the semiconductor packaging company jumped 17% in extended trading. Here are a few details ‌on the partnership:• ⁠Under the agreement, Nvidia will make a prepayment to support the expansion ⁠of Amkor's U.S. advanced packaging operations, including capacity in Arizona. • Amkor already supplies advanced packaging for Nvidia's product portfolio, including data center processors, and the expanded deal aims to ‌bring new packaging technologies ​to market as AI infrastructure ​demand grows. • In ​June, Amkor entered a 10-year partnership ‌with TSMC, the world's ​largest contract ​chipmaker, to enhance semiconductor packaging capabilities in the United States.