The IDM — Integrated Device Manufacturer, the company that designs AND manufactures its own chips end to end — was the dominant semiconductor business model from the 1960s through the early 2000s. It is now a shrinking minority at the leading edge, displaced by the fabless / foundry split covered in lessons sc1_l1 and sc1_l4. But the IDM model has not disappeared — it remains structurally dominant in memory (DRAM, NAND), analog, and many automotive / industrial categories, and two of the largest IDMs in the world — Intel and Samsung Electronics — operate at scales that no fabless designer can match.

This lesson is about the IDM model in 2024-2025: why Intel is restructuring into IDM-plus-foundry, how Samsung's multi-business integration plays out, and the structural economics that make IDMs simultaneously the highest-capex and highest-execution-risk business model in semiconductors. The historical IDM model integrated four activities under one corporate roof: chip design, mask manufacturing, wafer fabrication, and assembly / test.