Topic
HBM4 and HBM4E generations: commercialization timing, speeds, layer counts and supplier positioning.
Micron's HBM design fellow says the memory's roughly threefold wafer-area penalty against DDR5 grows with every generation. The pricing that follows does not mean-revert on its own.
Reality
Copper-to-copper slips to HBM5 at the earliest, so HBM4E capacity has to come out of die thickness inside a 775-micron package. iHBM heat blocks cannot be retrofitted to parts already in design.
Reality
Taiwan and South Korea are splitting the AI server chain because demand exceeds what either can build. For 2026 supply forecasts, the binding step is the handoff, not any single fab.
Reality
Jun Young-hyun credits only about 30 percent of Samsung's record quarter to Samsung, and treats first-to-market HBM4 as a starting line. That is a pricing warning, not modesty.
Reality