Dual deck three-dimensional NAND memory with channel dips and method for forming the same

    公开(公告)号:US11456315B2

    公开(公告)日:2022-09-27

    申请号:US16909566

    申请日:2020-06-23

    摘要: A method for forming a three-dimensional (3D) memory device is disclosed. In some embodiments, the method includes forming an alternating dielectric stack on a substrate, and forming a plurality of channel holes penetrating the alternating dielectric stack vertically to expose at least a portion of the substrate. A first mask can be formed to cover the channel holes in a first area and expose the channel holes in a second area. The method also includes forming a recess in the alternating dielectric stack in the second area, followed by forming a second mask in the recess. The second mask covers the channel holes in the second area and exposes the channel holes in the first area. The memory film at bottom of each channel hole in the first area can therefore be removed, while the memory film in the second area can be protected by the second mask.

    THREE-DIMENSIONAL MEMORY DEVICE WITH CORROSION-RESISTANT COMPOSITE SPACER

    公开(公告)号:US20210104540A1

    公开(公告)日:2021-04-08

    申请号:US17100841

    申请日:2020-11-21

    摘要: Embodiments of a three-dimensional (3D) memory device with a corrosion-resistant composite spacer and method for forming the same are disclosed. In an example, a method for forming a 3D memory device is disclosed. A dielectric stack including a plurality of dielectric/sacrificial layer pairs is formed on a substrate. A memory string extending vertically through the dielectric stack is formed. A slit extending vertically through the dielectric stack is formed. A memory stack is formed on the substrate including a plurality of conductor/dielectric layer pairs by replacing, with a plurality of conductor layers, the sacrificial layers in the dielectric/sacrificial layer pairs through the slit. A composite spacer is formed along a sidewall of the slit. The composite spacer includes a first silicon oxide film, a second silicon oxide film, and a dielectric film formed laterally between the first silicon oxide film and the second silicon oxide film. A slit contact extending vertically in the slit is formed.

    Three-dimensional memory device with corrosion-resistant composite spacer

    公开(公告)号:US11594552B2

    公开(公告)日:2023-02-28

    申请号:US17100841

    申请日:2020-11-21

    摘要: Embodiments of a three-dimensional (3D) memory device with a corrosion-resistant composite spacer and method for forming the same are disclosed. In an example, a method for forming a 3D memory device is disclosed. A dielectric stack including a plurality of dielectric/sacrificial layer pairs is formed on a substrate. A memory string extending vertically through the dielectric stack is formed. A slit extending vertically through the dielectric stack is formed. A memory stack is formed on the substrate including a plurality of conductor/dielectric layer pairs by replacing, with a plurality of conductor layers, the sacrificial layers in the dielectric/sacrificial layer pairs through the slit. A composite spacer is formed along a sidewall of the slit. The composite spacer includes a first silicon oxide film, a second silicon oxide film, and a dielectric film formed laterally between the first silicon oxide film and the second silicon oxide film. A slit contact extending vertically in the slit is formed.

    THREE-DIMENSIONAL MEMORY DEVICES AND FABRICATING METHODS THEREOF

    公开(公告)号:US20210118891A1

    公开(公告)日:2021-04-22

    申请号:US17112045

    申请日:2020-12-04

    摘要: A method for forming a gate structure of a 3D memory device is provided. The method comprises: forming, on a substrate, an alternating dielectric stack including a plurality of dielectric layer pairs, each of the plurality of dielectric layer pairs comprising a first dielectric layer and a second dielectric layer different from the first dielectric layer; forming a slit penetrating vertically through the alternating dielectric stack and extending in a horizontal direction; removing the plurality of second dielectric layers in the alternating dielectric stack through the slit to form a plurality of horizontal trenches; forming a gate structure in each of the plurality of horizontal trenches; forming a spacer layer on sidewalls of the slit to cover the gate structures, wherein the spacer layer has a laminated structure; and forming a conductive wall in the slit, wherein the conductive wall is insulated from the gate structures by the spacer layer.

    Three-dimensional memory devices and fabricating methods thereof

    公开(公告)号:US11469248B2

    公开(公告)日:2022-10-11

    申请号:US17112496

    申请日:2020-12-04

    摘要: A three-dimensional (3D) NAND memory device is provided. The device comprises an alternating stack including a plurality of dielectric/conductive layer pairs each comprising a dielectric layer and a conductive layer. The device further comprises a conductive wall vertically penetrating through the alternating stack and extending in a horizontal direction, and a spacer layer on sidewalls of the conductive wall configured to insulate the conductive wall from the conductive layers of the alternating stack. The spacer layer comprises a first spacer sublayer having a first dielectric material, a second spacer sublayer having a second dielectric material, and a third spacer sublayer having a third dielectric material. The second spacer is sandwiched between the first spacer sublayer and the third spacer sublayer. A second k-value of the second dielectric material is higher than a first k-value of the first dielectric material and higher than a third k-value of the third dielectric material.

    Three-dimensional memory devices and fabricating methods thereof

    公开(公告)号:US11476277B2

    公开(公告)日:2022-10-18

    申请号:US17112045

    申请日:2020-12-04

    摘要: A method for forming a gate structure of a 3D memory device is provided. The method comprises: forming, on a substrate, an alternating dielectric stack including a plurality of dielectric layer pairs, each of the plurality of dielectric layer pairs comprising a first dielectric layer and a second dielectric layer different from the first dielectric layer; forming a slit penetrating vertically through the alternating dielectric stack and extending in a horizontal direction; removing the plurality of second dielectric layers in the alternating dielectric stack through the slit to form a plurality of horizontal trenches; forming a gate structure in each of the plurality of horizontal trenches; forming a spacer layer on sidewalls of the slit to cover the gate structures, wherein the spacer layer has a laminated structure; and forming a conductive wall in the slit, wherein the conductive wall is insulated from the gate structures by the spacer layer.