Three-dimensional memory device with doped semiconductor bridge structures and methods for forming the same
摘要
說明書
According to another aspect of the present disclosure, a method of forming a three-dimensional memory device is provided, which comprises: forming a vertically alternating sequence of continuous insulating layers and continuous sacrificial material layers over a substrate; forming arrays of memory opening through the vertically alternating sequence; forming arrays of memory opening fill structures in the arrays of memory openings, wherein each of the memory opening fill structures comprises a respective vertical stack of memory elements; forming backside trenches laterally extending along a first horizontal direction through the vertically alternating sequence, wherein a plurality of alternating stacks of insulating layers and sacrificial material layers are laterally spaced apart by the backside trenches; forming first bridge structures comprising a first doped semiconductor material within each of the backside trenches at a first vertical distance from a horizontal plane including a top surface of the substrate; forming second bridge structures comprising a second doped semiconductor material within each of the backside trenches at a second vertical distance from the horizontal plane including the top surface of the substrate, wherein the second vertical distance is less than the first vertical distance; and replacing the sacrificial material layers with electrically conductive layers while the first and the second bridge structures are present within the backside trenches.
