US Patent 11024641 Three-dimensional memory devices and fabricating methods thereof

A method for forming a 3D memory device is disclosed. The method includes: forming an alternating dielectric stack on a substrate; forming a temporary top selective gate cut in an upper portion of the alternating dielectric stack and extending along a lateral direction; forming a plurality of channel holes penetrating the alternating dielectric stack; removing the temporary top selective gate cut; and forming, simultaneously, a plurality of channel structures in the plurality of channel holes and a top selective gate cut structure.