Semiconductor die assemblies with sidewall protection and associated methods and systems

A method, comprising:

• providing an interface wafer including first semiconductor dies and dicing lanes between the first semiconductor dies, wherein each of the first semiconductor dies has integrated circuitry formed in a substrate of the interface wafer;
• forming a dielectric layer on the interface wafer, wherein the dielectric layer includes a low-k dielectric material and conductive components coupled to the integrated circuitry, and wherein the conductive components are absent in portions of the dielectric layer including the dicing lanes;
• attaching the interface wafer including the dielectric layer to a carrier wafer such that the dielectric layer faces the carrier wafer;
• and
• removing the portions of the dielectric layer and part of the substrate corresponding to the portions of the dielectric layer using a plasma dicing process.

A semiconductor die assembly, comprising:

• a controller die including a substrate having a first side in contact with a dielectric layer including a low-k dielectric material and conductive components coupled to integrated circuitry of the substrate;
• one or more memory dies attached to a second side of the substrate opposite to the first side, the one or more memory dies operatively coupled to the integrated circuitry;
• a passivation layer in contact with the dielectric layer, wherein the passivation layer is opposite to the substrate of the controller die, and wherein the passivation layer includes a ledge uncovered by the dielectric layer;
• and
• a molding structure in contact with the ledge and surrounding first sidewalls of the substrate, second sidewalls of the dielectric layer, and third sidewalls of the one or more memory dies.