Convex shaped thin-film transistor device
View Patent ↗The present invention provides a semiconductor device that has a shorter distance between the bit lines and easily achieves higher storage capacity and density, and a method of manufacturing such a semiconductor device. The semiconductor device includes: first bit lines formed on a substrate; an insulating layer that is provided between the first bit lines on the substrate, and has a higher upper face than the first bit lines; channel layers that are provided on both side faces of the insulating layer, and are coupled to the respective first bit lines; and charge storage layers that are provided on the opposite side faces of the channel layers from the side faces on which the insulating layers are formed.
1. A semiconductor device comprising:
a plurality of first bit lines comprising a plurality of upper faces, the plurality of first bit lines provided on a substrate, the substrate comprising a surface;
an insulating layer that is provided between the plurality of first bit lines on the substrate, the insulating layer comprising opposing side faces, wherein an upper face of the insulating layer is higher than a plurality of upper faces of the plurality of first bit lines;
a plurality of channel layers provided on the side faces of the insulating layer and coupled to the respective first bit lines of the plurality of first bit lines; and
an ONO film comprising a top oxide film, a tunnel oxide film, and a plurality of charge storage layers, the top oxide film and the tunnel oxide film each comprising top, bottom and side surfaces,
wherein the plurality of charge storage layers is provided between the side surfaces of the top oxide film and the tunnel oxide film,
further wherein at least a portion of the bottom surface of the top oxide film is in direct contact with the top surface of the tunnel oxide film.
2. The semiconductor device as claimed in claim 1 , wherein the channel layers are coupled to each other on the insulating layer to form one channel layer.
3. The semiconductor device as claimed in claim 1 , further comprising
a second bit line that is provided on the insulating layer and is coupled to the channel layers.
4. The semiconductor device as claimed in claim 1 , wherein:
the substrate has a groove between the bit lines, and
the insulating layer is formed in the groove.
5. The semiconductor device as claimed in claim 1 , wherein the insulating layer has side faces oblique with respect to a surface of the substrate.
6. The semiconductor device as claimed in claim 1 , wherein the charge storage layers of the plurality of charge storage layers are physically separated by the top surface of the tunnel oxide film.
7. The semiconductor device as claimed in claim 1 , wherein the channel layers include polysilicon layers.
8. The semiconductor device as claimed in claim 1 , wherein the charge storage layers include silicon nitride films.
9. The semiconductor device as claimed in claim 1 , wherein the substrate is an insulating substrate.
10. The semiconductor device as claimed in claim 1 , further comprising word lines that are perpendicular to the first bit lines, an insulating film being interposed between the word lines and the charge storage layers.
11. The semiconductor device as claimed in claim 1 , wherein the charge storage layers include floating gates.
12. The semiconductor device as claimed in claim 1 , wherein at least a portion of the word lines comprises a gate.
13. The semiconductor device as claimed in claim 1 , wherein the plurality of charge storage layers are formed on the side faces of the insulating layer according to a sidewall technique.
14. The semiconductor device as claimed in claim 13 , wherein the plurality of charge storage layers are formed by isolating two portions of a single contiguous charge storage layer from each other via etching.
15. A semiconductor device, comprising:
a processor;
a cache;
a user input component; and
a flash memory comprising:
a plurality of first bit lines comprising a plurality of upper faces, the plurality of first bit lines provided on a substrate, the substrate comprising a surface;
an insulating layer that is provided between the plurality of first bit lines on the substrate, the insulating layer comprising opposing side faces wherein an upper face of the insulating layer is higher than a plurality of upper faces of the plurality of first bit lines;
a plurality of channel layers provided on both side faces of the insulating layer and coupled to the respective first bit lines; and
an ONO film comprising a top oxide film, a tunnel oxide film, and a plurality of charge storage layers,
wherein the top oxide film and the tunnel oxide film each comprises top, bottom and side surfaces,
wherein the plurality of charge storage layers is provided between the side surfaces of the top oxide film and the tunnel oxide film, and are separated by the top surface of the tunnel oxide film,
further wherein at least a portion of the bottom surface of the top oxide film is in direct contact with the top surface of the tunnel oxide film.
16. The semiconductor device as recited in claim 15 wherein the system is a personal computer (PC).
17. The semiconductor device as recited in claim 15 wherein the system is a personal digital assistant (PDA).
18. The semiconductor device as recited in claim 15 wherein the system is a gaming system.
19. The semiconductor device as recited in claim 15 wherein the system is a portable media player.
20. The semiconductor device as recited in claim 15 wherein the system is a cellular telephone.
21. The semiconductor device as claimed in claim 15 , wherein the charge storage layers include floating gates.
22. The semiconductor device as claimed in claim 15 , wherein at least a portion of the word lines comprises a gate.
23. The semiconductor device as claimed in claim 15 , wherein the plurality of charge storage layers are formed on the side faces of the insulating layer according to a sidewall technique.
24. The semiconductor device as claimed in claim 23 , wherein the charge storage layers of the plurality of charge storage layers are physically separated by the top surface of the tunnel oxide.