Abstract: Embodiments of through array contact structures of a 3D memory device and fabricating method thereof are disclosed. The memory device includes an alternating layer stack disposed on a first substrate. The alternating layer stack includes a first region including an alternating dielectric stack, and a second region including an alternating conductor/dielectric stack. The memory device further includes a barrier structure extending vertically through the alternating layer stack to laterally separate the first region from the second region, multiple through array contacts in the first region, each through array contact extending vertically through the alternating dielectric stack, an array interconnection layer in contact with the through array contacts, a peripheral circuit formed on a second substrate. and a peripheral interconnection layer on the peripheral circuit.

Abstract: Embodiments of structures and methods for testing three-dimensional (3D) memory devices are disclosed. In one example, a 3D memory device includes a memory array structure, a peripheral device structure, and an interconnect layer in contact with a front side of the memory array structure and a front side of the peripheral device structure, and a conductive pad at a back side of the memory array structure and that overlaps the memory array structure. The memory array structure includes a memory array stack, a through array contact (TAC) extending vertically through at least part of the memory array stack, and a memory array contact. The peripheral device structure includes a test circuit. The interconnect layer includes an interconnect structure. The conductive pad, the TAC, the interconnect structure, and at least one of the test circuit and the memory array contact are electrically connected.

Abstract: Embodiments of three-dimensional (3D) memory devices and methods for controlling a photoresist (PR) trimming rate in the formation of the 3D memory devices are disclosed. In an example, a method includes forming a dielectric stack over a substrate, measuring a first distance between the first trimming mark and the PR layer along a first direction, and trimming the PR layer along the first direction. The method also includes etching the dielectric stack using the trimmed PR layer as an etch mask to form a staircase, forming a second trimming mark using the first trimming mark as an etch mask, measuring a second distance between the second trimming mark and the trimmed PR layer, comparing the first distance with the second distance to determine a difference between an actual PR trimming rate and an estimated PR trimming rate, and adjusting PR trimming parameters based on the difference.

Abstract: Embodiments of source structure of a three-dimensional (3D) memory device and method for forming the source structure of the 3D memory device are disclosed. In an example, a NAND memory device includes a substrate, an alternating conductor/dielectric stack, a NAND string, a source conductor layer, and a source contact. The alternating conductor/dielectric stack includes a plurality of conductor/dielectric pairs above the substrate. The NAND string extends vertically through the alternating conductor/dielectric stack. The source conductor layer is above the alternating conductor/dielectric stack and is in contact with an end of the NAND string. The source contact includes an end in contact with the source conductor layer. The NAND string is electrically connected to the source contact by the source conductor layer. In some embodiments, the source conductor layer includes one or more conduction regions each including one or more of a metal, a metal alloy, and a metal silicide.