What new problems do HBM4 stacks, large-format CoWoS packaging and glass substrates hand to packaging adhesives?

“These three architectures tighten three constraints inside the same window. HBM4 widens the interface to 2048-bit and moves the base die to a 4 nm logic process, and shipping parts already run from the JEDEC baseline of 8 Gbps to 11.7 Gbps, putting per-stack bandwidth in the 3.3 TB/s range.”