Vertical neuromorphic devices stacked structure and array of the structure
Provided is a vertical neuromorphic devices stacked structure comprising a main gate which is formed on a substrate and has a vertical pillar shape, a main gate insulating layer stack formed on outer side surface of the main gate; a semiconductor region formed on outer side surface of the main gate insulating layer stack, a plurality of electrode layers formed on the side surface of the semiconductor region, a plurality of control gates formed on the side surface of the semiconductor region; and a plurality of control gate insulating layer stacks which are surrounding surfaces of the control gates and are formed between the control gate and the semiconductor region, and between the control gate and the electrode layer, and wherein the electrode layers and the control gates surrounded by the control gate insulating layer stack are stacked sequentially and alternately on the side surface of the semiconductor region.
1. A vertical neuromorphic devices stacked structure comprising:
a main gate formed on a substrate and having a vertical pillar shape;
a main gate insulating layer stack formed vertically on an outer vertical surface of the main gate;
a semiconductor region formed vertically on an outer vertical surface of the main gate insulating layer stack;
a plurality of electrode layers formed on an outer vertical surface of the semiconductor region, the electrode layers being apart from each other along the outer vertical surface of the semiconductor region;
a control gate formed between two neighboring electrode layers; and
a control gate insulating layer stack formed between the semiconductor region and the control gate and between the control gate and the two neighboring electrode layers in such a way that the control gate is insulated from the semiconductor region and the two neighboring electrode layers.
2. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the main gate insulating layer stack is formed of a single insulating material, or formed of a plurality of layers including at least one charge storage layer and an insulating film.
3. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the control gate insulating layer stack formed between the control gate and the semiconductor region is formed of a plurality of layers including at least one charge storage layer and an insulating film.
4. The vertical neuromorphic devices stacked structure according to claim 1 , wherein each of the control gate insulating layer stack and the main gate insulating layer stack is formed of a plurality of layers including at least one charge storage layer and an insulating film, and
wherein the at least one charge storage layer of the control gate insulating layer stack is formed of a material having a dielectric constant different from that of the main gate insulating layer stack, or the at least one charge storage layer of the control gate insulating layer stack has a charge storage duration different from that of the main gate insulation.
5. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the electrode layers are formed of semiconductor electrodes doped with impurities, and an impurity-type of the two neighboring electrode layers is opposite to each other.
6. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the electrode layers are formed of semiconductor electrodes doped with impurities, and an impurity-type of the two neighboring electrode layers is same.
7. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the electrode layers are doped with impurities, and an impurity-type of the two neighboring electrode layers is same, and
wherein the semiconductor region is doped with impurity of which an impurity-type is opposite to that of the electrode layers.
8. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the control gate insulating layer stack includes a charge storage layer, and
wherein charges stored in the charge storage layer are controlled so that threshold voltage of a FET (Field Effect Transistor) consisting of the control gate, the control gate insulating layer stack, two electrodes adjacent the control gate, and the semiconductor region is controlled.
9. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the control gate insulating layer stack includes at least one charge storage layer and at least one insulating film, and
wherein an amount and type of charges stored in the control gate insulating layer stack is controlled so that the control gate functions as a switch which electrically isolates vertically adjacent vertical neuromorphic devices from each other.
10. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the control gate insulating layer stack or the main gate insulating layer stack is formed of a plurality of layers including two charge storage layers and at least one insulating film, and
wherein the charge storage layers are formed to be in contact with each other or separated from each other by an insulating layer.
11. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the electrode layers include three sequential electrode layers.
12. The vertical neuromorphic devices stacked structure according to claim 1 , wherein the electrode layers include two electrode layers.
13. An array comprising a plurality of vertical neuromorphic devices stacked structures according to claim 1 , wherein the vertical neuromorphic devices stacked structures are disposed on a single substrate, and
wherein the vertical neuromorphic devices stacked structures share the control gate and the electrode layers of a same stacked layer, and the main gates of the vertical neuromorphic devices stacked structures are electrically isolated from each other.
14. The vertical neuromorphic devices stacked structure according to claim 2 , wherein a program or erase operation is performed by injecting carriers (electrons or holes) to the at least one charge storage layer from the main gate or the semiconductor region.
15. The vertical neuromorphic devices stacked structure according to claim 5 , wherein each of the control gate insulating layer stack and the main gate insulating layer stack is formed of a plurality of layers including at least one charge storage layer and an insulating film, and the at least one charge storage layer is formed of an insulating film including traps or nano-sized particles, or an electrode.
16. The vertical neuromorphic devices stacked structure according to claim 10 , wherein one of the charge storage layers of the control gate insulating layer stack contacts to the semiconductor region or the control gate, or one of the main gate insulating layer stack contacts to the semiconductor region or the main gate.
17. The vertical neuromorphic devices stacked structure according to claim 11 , further including two additional control gates disposed at both sides or an additional control gate disposed at one side of the three electrode layers,
wherein the additional control gate is configured to function as a switch which electrically isolates vertically adjacent vertical neuromorphic devices from each other by controlling charges stored in a charge storage layer of the control gate insulating layer stack.
18. The vertical neuromorphic devices stacked structure according to claim 12 , further including two additional control gates disposed at both sides or an additional control gate disposed at one side of the two electrode layers,
wherein the additional control gate is configured to function as a switch which electrically isolates vertically adjacent vertical neuromorphic devices from each other by controlling charges stored in a charge storage layer of the control gate insulating layer stack.
19. The array comprising a plurality of vertical neuromorphic devices stacked structures according to claim 13 , wherein two additional electrode layers disposed at both ends of a vertical neuromorphic device in the vertical neuromorphic devices stacked structure are formed to be connected to two independent paths of a current mirror circuit, respectively.
20. The array comprising a plurality of vertical neuromorphic devices stacked structures according to claim 13 , wherein the single substrate is formed of an insulating material or a semiconductor, in the case where the single substrate is configured with an insulating material, a semiconductor layer is formed under the single substrate and the semiconductor layer includes peripheral devices and circuits for the array.