Assembly, test, marking and packaging (ATMP/OSAT) plants that turn wafers into finished chips - where India's chip manufacturing actually started in 2026.
Wafers are sawn into individual dies, attached to a substrate, wired with fine gold or copper bonds, sealed in plastic and tested. OSAT plants cost far less than fabs (₹3,000-27,000 Cr here vs ₹91,000 Cr for Tata's fab) and start sooner, which is why most Semicon 1.0 projects are OSATs.
Five Semicon 1.0 plants are in commercial production: Micron (Sanand, Feb 2026), Kaynes (Sanand, Mar 2026), CG Semi (Sanand, inaugurated 4 Jul 2026), CDIL (Mohali) and Suchi (Surat, both Sep 2026). Tata's Assam plant began pilot production in Oct 2026. Semicon 2.0 keeps funding this layer: 25% of capital cost for legacy packaging and 35% for advanced packaging, for projects of at least ₹1,000 Cr.
Global OSATs earn high single-digit to low-teens operating margins at scale, but new plants run at a loss until volumes build. Value is in utilisation and customer qualification (automotive chips can take 1-2 years to qualify). For listed parents (CG Power, Kaynes) the units are small today relative to the group.