Abstract: Embodiments of the present disclosure provide a method for forming a hole structure in a semiconductor device. The method for forming a hole structure having a first hole portion and a second hole portion connected to and over the first portion in a stack structure of a semiconductor device includes determining a hard mask layer. An etching resistivity of the hard mask layer may be inversely proportional to a difference between a first lateral dimension of the first hole portion and a second lateral dimension of the second hole portion, and the first lateral dimension may be less than the second lateral dimension. The method may also include forming the hard mask layer over the stack structure, and patterning the hard mask layer to form a first patterned hard mask layer that has a first mask opening. The first mask opening may have the first lateral dimension.

Abstract: Embodiments of the present disclosure provide a method for forming a hole structure in a semiconductor device. The method includes forming a first etch mask over a stack structure, and removing a portion of the stack structure exposed by the first etch mask. The first etch mask may have a first mask opening with a first lateral dimension. The method may also include forming a second etch mask from the first etch mask. The second etch mask may have a second mask opening with a second lateral dimension that is greater than the first lateral dimension. The method may further include removing another portion of the stack structure exposed by the second etch mask to form the hole structure having a first hole portion and a second hole portion connected to and over the first hole portion.

Abstract: Embodiments of the present disclosure provide a method for forming a hole structure in a semiconductor device. The method for forming a hole structure having a first hole portion and a second hole portion connected to and over the first portion in a stack structure of a semiconductor device includes determining a hard mask layer. An etching resistivity of the hard mask layer may be inversely proportional to a difference between a first lateral dimension of the first hole portion and a second lateral dimension of the second hole portion, and the first lateral dimension may be less than the second lateral dimension. The method may also include forming the hard mask layer over the stack structure, and patterning the hard mask layer to form a first patterned hard mask layer that has a first mask opening. The first mask opening may have the first lateral dimension.

Abstract: A method for forming a staircase structure of 3D memory, including: forming an alternating layer stack on a substrate, forming a plurality of staircase regions where each staircase region has a staircase structure having a first number (M) of steps in a first direction; forming a first mask stack to expose a plurality of the staircase regions; removing (M) of the layer stacks in the exposed staircase regions; forming a second mask stack over the alternating layer stack to expose at least an edge of each of the staircase regions in a second direction; and repetitively, sequentially, removing a portion of (2M) of layer stacks and trimming the second mask stack.

Abstract: A method for forming a staircase structure of 3D memory, including: forming an alternating layer stack on a substrate, forming a plurality of staircase regions where each staircase region has a staircase structure having a first number (M) of steps in a first direction; forming a first mask stack to expose a plurality of the staircase regions; removing (M) of the layer stacks in the exposed staircase regions; forming a second mask stack over the alternating layer stack to expose at least an edge of each of the staircase regions in a second direction; and repetitively, sequentially, removing a portion of (2M) of layer stacks and trimming the second mask stack.

Abstract: Embodiments of the present disclosure provide a method for forming a hole structure in a semiconductor device. The method includes forming a first etch mask over a stack structure, and removing a portion of the stack structure exposed by the first etch mask. The first etch mask may have a first mask opening with a first lateral dimension. The method may also include forming a second etch mask from the first etch mask. The second etch mask may have a second mask opening with a second lateral dimension that is greater than the first lateral dimension. The method may further include removing another portion of the stack structure exposed by the second etch mask to form the hole structure having a first hole portion and a second hole portion connected to and over the first hole portion.

Abstract: A method for forming a staircase structure of 3D memory, including: forming an alternating layer stack on a substrate, forming a plurality of staircase regions where each staircase region has a staircase structure having a first number (M) of steps in a first direction; forming a first mask stack to expose a plurality of the staircase regions; removing (M) of the layer stacks in the exposed staircase regions; forming a second mask stack over the alternating layer stack to expose at least an edge of each of the staircase regions in a second direction; and repetitively, sequentially, removing a portion of (2M) of layer stacks and trimming the second mask stack.