Semiconductor device and semiconductor memory device that include an oxide semiconductor layer provided between a first electrode and a second electrode
A semiconductor device of embodiments includes: a first electrode; a second electrode; an oxide semiconductor layer provided between the first electrode and the second electrode; a gate electrode surrounding the oxide semiconductor layer; and a gate insulating layer provided between the gate electrode and the oxide semiconductor layer, spaced from the first electrode, and containing nitrogen (N). In addition, a first distance between the first electrode and the gate insulating layer in a first direction from the first electrode to the second electrode is smaller than a second distance between the first electrode and the gate electrode in the first direction.
1 . A semiconductor device, comprising:
a first electrode;
a second electrode;
an oxide semiconductor layer provided between the first electrode and the second electrode, and the oxide semiconductor layer being in contact with the first electrode;
a gate electrode surrounding the oxide semiconductor layer;
a gate insulating layer provided between the gate electrode and the oxide semiconductor layer, the gate insulating layer spaced from the first electrode, and the gate insulating layer containing nitrogen (N); and
a first insulating layer provided between the first electrode and the gate insulating layer in a first direction from the first electrode to the second electrode,
wherein a first distance between the first electrode and the gate insulating layer in the first direction is smaller than a second distance between the first electrode and the gate electrode in the first direction.
2 . The semiconductor device according to claim 1 ,
wherein the first distance is larger than a thickness of the gate insulating layer.
3 . The semiconductor device according to claim 1 ,
wherein a difference between the second distance and the first distance is larger than a thickness of the gate insulating layer.
4 . The semiconductor device according to claim 1 ,
wherein the gate insulating layer includes a first region and a second region between the oxide semiconductor layer and the first region, and a nitrogen concentration in the first region is higher than a nitrogen concentration in the second region.
5 . The semiconductor device according to claim 4 ,
wherein the first region is provided between the first electrode and the second region in the first direction.
6 . The semiconductor device according to claim 4 ,
wherein the first region contains silicon nitride, and the second region contains silicon oxide.
7 . The semiconductor device according to claim 4 ,
wherein a thickness of the second region is larger than a thickness of the first region.
8 . The semiconductor device according to claim 1 ,
wherein the gate insulating layer is in contact with the second electrode.
9 . The semiconductor device according to claim 1 ,
wherein the gate insulating layer is spaced from the second electrode.
10 . The semiconductor device according to claim 1 ,
wherein, in a cross section parallel to the first direction, a length of an interface between the first electrode and the oxide semiconductor layer in a second direction perpendicular to the first direction is shorter than a length of an interface between the second electrode and the oxide semiconductor layer in the second direction.
11 . A semiconductor memory device, comprising:
the semiconductor device according to claim 1 ; and
a capacitor electrically connected to the first electrode or the second electrode.
12 . A semiconductor device, comprising:
a first electrode;
a second electrode;
an oxide semiconductor layer provided between the first electrode and the second electrode, and the oxide semiconductor layer being in contact with the first electrode;
a gate electrode surrounding the oxide semiconductor layer;
a gate insulating layer provided between the gate electrode and the oxide semiconductor layer, the gate insulating layer spaced from the first electrode, the gate insulating layer including a first region and a second region between the first region and the oxide semiconductor layer, and a nitrogen concentration in the first region being higher than a nitrogen concentration in the second region; and
a first insulating layer provided between the first electrode and the gate insulating layer in a first direction from the first electrode to the second electrode.
13 . The semiconductor device according to claim 12 ,
wherein the first region is provided between the first electrode and the second region in the first direction.
14 . The semiconductor device according to claim 12 ,
wherein the first region contains silicon nitride, and the second region contains silicon oxide.
15 . The semiconductor device according to claim 12 ,
wherein a thickness of the second region is larger than a thickness of the first region.
16 . The semiconductor device according to claim 12 ,
wherein the first distance between the first electrode and the gate insulating layer in the first direction is larger than a thickness of the gate insulating layer.
17 . The semiconductor device according to claim 12 ,
wherein the gate insulating layer is in contact with the second electrode.
18 . The semiconductor device according to claim 12 ,
wherein the gate insulating layer is spaced from the second electrode.
19 . The semiconductor device according to claim 12 ,
wherein, in a cross section parallel to the first direction, a length of an interface between the first electrode and the oxide semiconductor layer in a second direction perpendicular to the first direction is shorter than a length of an interface between the second electrode and the oxide semiconductor layer in the second direction.
20 . A semiconductor device, comprising:
the semiconductor device according to claim 12 ; and
a capacitor electrically connected to the first electrode or the second electrode.