Thermal is a huge issue because Dennard Scaling has been dead for a long time. We are kind of limping along with Moore but anything that looks like Dennard is going to involve a change of materials or new chemistry.
I get the impression that backside power was the last big Dennard-adjacent win, and that’s more about relocating some of the heat to a spot closer to the chip surface, which gives thermal conductivity a boost since the heat has to move a shorter distance to get out. I think that leaves gallium, optical communication to create less heat in the bulk of the chip, and maybe new/cheaoer silicon on insulator improvements for less parasitic loss? What other things are still in the bag of tricks? Because smaller gates isn’t.
I get the impression that backside power was the last big Dennard-adjacent win, and that’s more about relocating some of the heat to a spot closer to the chip surface, which gives thermal conductivity a boost since the heat has to move a shorter distance to get out. I think that leaves gallium, optical communication to create less heat in the bulk of the chip, and maybe new/cheaoer silicon on insulator improvements for less parasitic loss? What other things are still in the bag of tricks? Because smaller gates isn’t.