A semiconductor structure includes a memory die bonded to a logic die. The memory die includes an alternating stack of insulating layers and electrically conductive layers; memory openings extending through the alternating stack, memory opening fill structures located in the memory openings and comprising a respective vertical semiconductor channel and a respective memory film, a source layer contacting the vertical semiconductor channels, a backside isolation dielectric layer contacting a backside surface of the source layer, and a source power supply mesh including a planar portion of a source-side electrically conductive layer that is located on a backside of the backside isolation dielectric layer and electrically connected to the source layer by conductive material portions that extend through the backside isolation dielectric layer.