ICHEON, South Korea, May 2 (Reuters) - South Korea's SK Hynix said on Thursday its high-bandwidth memory (HBM) chips used in AI chipsets are almost sold out for 2025, after their 2024 chips were fully booked.

Chief Executive Officer Kwak Noh-Jung said the Nvidia supplier and the world's second-largest memory chipmaker will begin sending samples of the latest version of HBM chips, called 12-layer HBM3E, in May and begin mass producing them in the third-quarter.

Kwak said its HBM products this year had already sold out, while 2025 HBM volumes were almost sold out amid a rapid expansion of AI technology into a wider range of on-device applications such as smartphones, PCs, and automobiles.

Last month, SK Hynix announced new investment plans - a $3.87 billion plan to build an advanced chip packaging plant in the U.S. state of Indiana with an HBM chip line and a 5.3 trillion won ($3.85 billion) investment in a new DRAM chip factory at home with a focus on HBMs.

($1 = 1,375.6700 won) (Reporting by Joyce Lee and Heekyong Yang Editing by Ed Davies)