Semiconductor assemblies with redistribution structures for die stack signal routing

Semiconductor devices having redistribution structures, and associated systems and methods, are disclosed herein. In some embodiments, a semiconductor assembly comprises a die stack including a plurality of semiconductor dies, and a routing substrate mounted on the die stack. The routing substrate includes an upper surface having a redistribution structure. The semiconductor assembly also includes a plurality of electrical connectors coupling the redistribution structure to at least some of the semiconductor dies. The semiconductor assembly further includes a controller die mounted on the routing substrate. The controller die includes an active surface that faces the upper surface of the routing substrate and is electrically coupled to the redistribution structure, such that the routing substrate and the semiconductor dies are electrically coupled to the controller die via the redistribution structure.