backside power delivery
Beginner
Bringing power into the chip from underneath. That leaves the wires on top free to carry signals.
Novice
Putting the chip’s power wiring on the back of the silicon instead of in the stack of wiring layers above the transistors. The front layers are then left for signal wires, and power reaches the transistors through tiny vertical connections from below.
Expert
Separates the power delivery network from the signal metal stack, cutting IR drop and freeing routing tracks. It changes cell design, the heat path and failure analysis, because the substrate side is no longer open for probing.