Semiconductor memory device

• US 8,405,142 B2
• Filed: 03/09/2011
• Issued: 03/26/2013
• Est. Priority Date: 09/22/2010
• Status: Expired due to Fees

• Current Assignee: Toshiba Memory Corporation (Kioxia Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Katsumata, Ryota, Higashi, Kazuyuki, Fukuzumi, Yoshiaki
• Primary Examiner(s): Huynh, Andy
• Application Number:
  US13/043,714
• Publication Number:
  US 20120068252A1
• Time in Patent Office: 748 Days
• Field of Search: 257/314, 257/324, 257/325, 257/326, 257/E29.309
• US Class Current: 257/324
• CPC Class Codes: H01L 29/7926 Vertical transistors, i.e. transistors having source and drain not in the same horizontal plane
• CPC Class Codes: H10B 43/27 the channels comprising vertical portions, e.g. U-shaped channels
• CPC Class Codes: H10B 43/50 characterised by the boundary region between the core and peripheral circuit regions

Abstract

According to one embodiment, a semiconductor memory device includes a substrate, a multilayer body, a semiconductor member and a charge storage layer. The multilayer body is provided on the substrate, with a plurality of insulating films and electrode films alternately stacked, and includes a first staircase and a second staircase opposed to each other. The semiconductor member is provided in the multilayer body outside a region provided with the first staircase and the second staircase, and the semiconductor member extends in stacking direction of the insulating films and the electrode films. The charge storage layer is provided between each of the electrode films and the semiconductor member. The each of the electrode films includes a first terrace formed in the first staircase, a second terrace formed in the second staircase and a bridge portion connecting the first terrace and the second terrace.

Claims

1. A semiconductor memory device comprising:

a substrate;

a multilayer body provided on the substrate, with a plurality of insulating films and electrode films alternately stacked, including a valley made of a pair of staircases opposed to each other and including a terrace for each of the electrode films, and being not full divided by the valley;

a first contact connected to a portion of the each of the electrode films constituting the terrace of one of the staircases;

a second contact connected to a portion of the each of the electrode films constituting the terrace of another of the staircases;

an interconnection connected to the first contact and the second contact;

a semiconductor member provided in a portion of the multilayer body on a side of the first contact as viewed from the valley, the semiconductor member extending in a stacking direction of the insulating films and the electrode films; and

a charge storage layer provided between the each of the electrode films and the semiconductor member.

2. The device according to claim 1, wherein the each of the electrode films includes a bridge portion connecting a portion with the first contact connected to the each of the electrode films to a portion with the second contact connected to the each of the electrode films.

3. The device according to claim 1, wherein as viewed in the stacking direction, the each of the electrode films has a U-shape circumventing the valley.

4. The device according to claim 1, wherein as viewed in the stacking direction, the first terrace and the second terrace are arranged in a grid.

5. The device according to claim 1, wherein a shape of the one of the staircases is a mirror image of a shape of the another of the staircases.

6. The device according to claim 1, further comprising:

another multilayer body provided on the substrate, with a plurality of other insulating films and other electrode films alternately stacked, including another valley made of a pair of other staircases opposed to each other and including a terrace for each of the other electrode films, and being not full divided by the another valley;

another first contact connected to a portion of the each of the other electrode films constituting the terrace of one of the other staircases;

another second contact connected to a portion of the each of the other electrode films constituting the terrace of another of the other staircases;

another interconnection connected to the another first contact and the another second contact;

another semiconductor member provided in a portion of the another multilayer body on a side of the another first contact as viewed from the another valley, the another semiconductor member extending in the stacking direction; and

another charge storage layer provided between the each of the other electrode films and the another semiconductor member,

the another valley being in communication with the valley,

a shape of the one of the other staircases being a mirror image of a shape of the another of the other staircases,

a shape of the one of the staircases being a mirror image of the a shape of the one of the other staircases, and

a shape of the another of the staircases being a mirror image of the shape of the another of the other staircases.

7. The device according to claim 1, further comprising:

a first conductive film connected to an upper end of the first contact;

a second conductive film connected to an upper end of the second contact;

first vias with a lower end of one of the first vias connected to the first conductive film and an upper end of one of the first vias connected to the interconnection; and

second vias with a lower end of one of the second vias connected to the second conductive film and an upper end of one of the second vias connected to the interconnection,

the first via having a smaller diameter than the first contact, and the second via having a smaller diameter than the second contact, and

in a width direction of the interconnection, positions of the first vias are different from each other, positions of the second vias are different from each other, and the position of the first via connected to one of the electrode films is identical to the position of the second via connected to the one of the electrode films.