SK Hynix Inc., the semiconductor arm of SK Group, plans to invest 103 trillion won ($74.8 billion) through 2028, underscoring the conglomerate’s bet on a sector it considers crucial for future-proofing its businesses. About 80%, or 82 trillion won, will be allocated to investing in high-bandwidth memory chips, SK Group said in a statement on Sunday. SK Hynix’s HBM chips are optimized for use with Nvidia Corp.’s artificial intelligence accelerators. As part of its bet on AI, SK Telecom Co. and SK...