Memory utilizing oxide-nitride nanolaminates
Structures, systems and methods for transistors utilizing oxide-nitride nanolaminates are provided. One transistor embodiment includes a first source/drain region, a second source/drain region, and a channel region therebetween. A gate is separated from the channel region by a gate insulator. The gate insulator includes oxide-nitride nanolaminate layers to trap charge in potential wells formed by different electron affinities of the oxide-nitride nanolaminate layers.
1. A transistor, comprising:
a first source/drain region;
a second source/drain region;
a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator;
wherein the first source/drain region is integrally formed as a common sourceline that is shared between a pair of vertical transistors separated by a trench, and wherein the pair of vertical transistors are configured to compare a first transistor of the pair with a second transistor of the pair, the second transistor serving as a reference transistor;
wherein the gate insulator includes oxide-nitride nanolaminate layers formed using atomic layer deposition techniques;
wherein a nitride layer in the nanolaminate layers provides a positive conduction band offset with silicon; and
operation circuitry coupled to the transistor to program the transistor in a reverse direction and to read the transistor in a forward direction.
2. The transistor of claim 1 , wherein the nitride layer provides an electron affinity higher than an oxide layer electron affinity.
3. The transistor of claim 1 , wherein the nitride layer includes aluminum.
4. The transistor of claim 1 , wherein the nitride layer includes gallium.
5. The transistor of claim 1 , wherein the oxide-nitride nanolaminate layers include gallium aluminum nitride.
6. The transistor of claim 1 , wherein the oxide-nitride nanolaminate layers include tantalum aluminum nitride.
7. The transistor of claim 1 , wherein the oxide-nitride nanolaminate layers include titanium silicon nitride.
8. The transistor of claim 1 , wherein the oxide-nitride nanolaminate layers include titanium aluminum nitride.
9. The transistor of claim 1 , wherein the oxide-nitride nanolaminate layers include tungsten aluminum nitride.
10. A vertical multistate cell, comprising:
a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, wherein the gate insulator includes oxide-nitride nanolaminate layers adapted to trap charge in potential wells formed by different electron affinities of the oxide-nitride nanolaminate layers;
wherein the first source/drain region is integrally formed as a common sourceline that is shared between a pair of vertical transistors separated by a trench and wherein the pair of vertical transistors are configured to compare a first transistor of the pair with a second transistor of the pair, the second transistor serving as a reference transistor;
a transmission line coupled to the second source/drain region; and
wherein the MOSFET is a programmed MOSFET having one of a number of charge levels trapped in the gate insulator adjacent to the first source/drain region such that the channel region has a first voltage threshold region (Vt 1 ) and a second voltage threshold region (Vt 2 ).
11. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include silicon nitride.
12. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include aluminum nitride.
13. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include gallium nitride.
14. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include gallium aluminum nitride.
15. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include tantalum aluminum nitride.
16. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include titanium silicon nitride.
17. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include titanium aluminum nitride.
18. The vertical multistate cell of claim 10 , wherein the oxide-nitride nanolaminate layers include tungsten aluminum nitride.
19. The vertical multistate cell of claim 10 , wherein the first source/drain region of the MOSFET includes a source region and the second source/drain region of the MOSFET includes a drain region.
20. The vertical multistate cell of claim 19 , wherein the second voltage threshold region (b 2 ) in the channel is adjacent the source region, and wherein the first voltage threshold region (Vt 1 ) in the channel is adjacent the drain region.
21. The multistate cell of claim 20 , wherein the Vt 2 has a higher voltage threshold than the Vt 1 .
22. The vertical multistate cell of claim 10 , wherein the gate insulator has a thickness of approximately 1-10 nanometers (nm).
23. A vertical multistate cell, comprising:
a vertical metal oxide semiconductor field effect transistor (MOSFET) extending outwardly from a substrate, the MOSFET having a source region, a drain region, a channel region between the source region and the drain region, and a gate separated from the channel region by a gate insulator wherein the gate insulator includes oxide-nitride nanolaminate layers with charge trapping in potential wells formed by different electron affinities of the oxide-nitride nanolaminate layers;
a wordline coupled to the gate;
wherein the source region is integrally formed as a common sourceline that is shared between a pair of vertical transistors separated by a trench and wherein the pair of vertical transistors are configured to compare a first transistor of the pair with a second transistor of the pair, the second transistor serving as a reference transistor;
a bit line coupled to the drain region; and
wherein the MOSFET is a programmed MOSFET having a number of charge levels trapped in the gate insulator adjacent to the source region such that the channel region has a first voltage threshold region (Vt 1 ) adjacent to the drain region and a second voltage threshold region (Vt 2 ) adjacent to the source region, the Vt 2 having a greater voltage threshold than Vt 1 .
24. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include silicon nitride.
25. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include aluminum nitride.
26. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include gallium nitride.
27. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include gallium aluminum nitride.
28. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include tantalum aluminum nitride.
29. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include titanium silicon nitride.
30. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include titanium aluminum nitride.
31. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers include tungsten aluminum nitride.
32. The vertical multistate cell of claim 23 , wherein the oxide-nitride nanolaminate layers have atomic dimensions with precisely controlled interfaces and layer thickness formed by atomic layer deposition (ALD).
33. The vertical multistate cell of claim 23 , wherein the gate insulator has a thickness of approximately 1-10 nanometers (nm).
34. A transistor array, comprising:
a number of transistor cells formed on a substrate, wherein each transistor cell includes a first source/drain region, a second source/drain region, a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator, and wherein the gate insulator includes oxide-nitride nanolaminate layers with charge trapping in potential wells formed by different electron affinities of the oxide-nitride nanolaminate layers;
a number of bit lines coupled to the second source/drain region of each transistor cell along rows of the transistor array;
a number of word lines coupled to the gate of each transistor cell along columns of the memory array;
wherein the first source/drain regions are integrally formed as common sourcelines that are shared between pairs of vertical transistors separated by a trench and wherein the pairs of vertical transistors are configured to compare a first transistor of each pair with a second transistor of each pair, the second transistor serving as a reference transistor; and
wherein at least one of transistor cells is a programmed transistor having one of a number of charge levels trapped in the gate insulator adjacent to the first source/drain region such that the channel region has a first voltage threshold region (Vt 1 ) and a second voltage threshold region (Vt 2 ).
35. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include silicon nitride.
36. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include aluminum nitride.
37. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include gallium nitride.
38. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include gallium aluminum nitride.
39. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include tantalum aluminum nitride.
40. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include titanium silicon nitride.
41. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include titanium aluminum nitride.
42. The transistor array of claim 34 , wherein the oxide-nitride nanolaminate layers include tungsten aluminum nitride.
43. The transistor array of claim 34 , wherein the one of a number of charge levels trapped in the gate insulator includes a charge adjacent to the source of approximately 100 electrons.
44. The transistor array of claim 34 , wherein the first source/drain region of the transistor cell includes a source region and the second source/drain region of the transistor cell includes a drain region.
45. The transistor array of claim 34 , wherein the second voltage threshold region (Vt 2 ) in the channel is adjacent the first source/drain region, and wherein the first voltage threshold region (Vt 1 ) in the channel is adjacent the second source/drain region, and wherein Vt 2 has a higher voltage threshold than the Vt 1 .
46. The transistor array of claim 34 , wherein the gate insulator of each transistor cell has a thickness of approximately 1-10 nanometers (nm).
47. The transistor array of claim 34 , wherein the number of transistor cells extending from a substrate operate as equivalent to a transistor having a size equal to or than 1.0 lithographic feature squared (1F2).
48. A programmable logic array, comprising:
a plurality of input lines for receiving an input signal;
a plurality of output lines; and
one or more arrays having a first logic plane and a second logic plane connected between the input lines and the output lines, wherein the first logic plane and the second logic plane comprise a plurality of logic cells arranged in rows and columns for providing a sum-of-products term on the output lines responsive to a received input signal, wherein each logic cell includes a transistor cell including:
a first source/drain region;
a second source/drain region;
a channel region between the first and the second source/drain regions, and a gate separated from the channel region by a gate insulator;
wherein the first source/drain region is integrally formed as a common sourceline that is shared between a pair of vertical transistors separated by a trench and wherein the pair of vertical transistors are configured to compare a first transistor of the pair with a second transistor of the pair, the second transistor serving as a reference transistor; and
wherein the gate insulator includes oxide-nitride nanolaminate layers with charge trapping in potential wells formed by different electron affinities of the oxide-nitride nanolaminate layers and the transistor cell is a programmed transistor cell having charge trapped in the gate insulator adjacent to the first source/drain region or second source/drain region configured as a source region.
49. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include silicon nitride.
50. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include aluminum nitride.
51. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include gallium nitride.
52. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include gallium aluminum nitride.
53. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include tantalum aluminum nitride.
54. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include titanium silicon nitride.
55. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include titanium aluminum nitride.
56. The programmable logic array of claim 48 , wherein the oxide-nitride nanolaminate layers include tungsten aluminum nitride.