High-density interconnect and flexible boards with laser-drilled micro-holes - the boards inside phones, wearables and camera modules.
HDI boards use lasers to drill tiny holes and build layers up one at a time, fitting a phone's circuitry into a thumb-sized board. Flex boards bend to connect cameras and displays. Both are made in yellow-lit clean rooms.
Every phone mainboard is HDI, and none were made in India at scale. ECMS treats HDI/mSAP/flex as a priority 'hybrid' segment: a turnover incentive (8% falling to 4%) plus a 25% capex subsidy, with a minimum investment of ₹1,000 Cr.
Capital-heavy and technology-intensive - globally led by Taiwanese, Korean, Japanese and Austrian makers (AT&S). Fewer players and longer customer qualifications mean better margins than standard boards once a plant is qualified.