Samsung Electronics Co.’s chip unit plunged a far bigger-than-expected 94% in the June quarter, reflecting the depth of a slump that’s plaguing the world’s largest memory chipmaker.

The world’s largest maker of memory chips and smartphones posted lower quarterly net profit, but expects earnings to regain momentum in the second half of this year.

Just a few years ago, Samsung Electronics stood as a leading force in the global semiconductor race, dominating one chip sector and eyeing Taiwan’s TSMC in the battle for supremacy in another.