Japan's Ajinomoto cuts chip packaging film supply to China

Ajinomoto has reportedly told mainland Chinese customers it will cut supply of ABF (Ajinomoto Build-up Film), a material used in advanced chip packaging, by 30%. The move follows Beijing's recent rare earth export curbs, with Chinese firms racing to qualify domestic substitutes.

Why it matters: ABF is a chokepoint material for packaging high-end chips, including AI accelerators, so a supply cut squeezes China's semiconductor buildout from a different angle than the more familiar GPU export controls. It's a tit-for-tat escalation in the broader chip war, and China's push for a domestic substitute mirrors the same self-sufficiency drive seen in its move toward domestically supplying most of its own AI chips.