Micron Technology Inc. said it would buy the 67% stake in Taiwan’s Inotera Memories Inc. it doesn’t already own for $4.1 billion, solidifying control over a major source of memory chips.

The deal, valued at $3.2 billion net of cash, was announced along with an additional deal to license manufacturing technology to Nanya Technology Corp., another major Inotera investor based in Taiwan that is affiliated with Formosa Plastics Corp.

Micron’s...