SK hynix delays hybrid bonding for HBM until HBM5, cites 775-micron package limit
At Hot Chips 2026, SK hynix's Jaesik Lee said hybrid bonding won't be ready in time for HBM4E and will instead debut with HBM5, as current HBM4 packages are already constrained by a 775-micron thickness ceiling matching standard logic wafers. To keep scaling within that limit, 16-Hi HBM4 stacks now use dies thinned to about 50 microns with half the interlayer gap of 12-Hi designs, while SK hynix continues using its existing MR-MUF bonding method through upcoming Nvidia Rubin-generation products.