Memory element using reversible switching between SP2 and SP3 hybridized carbon
View Patent ↗An information storage element has a carbon storage material including hexagonally bonded carbon and tetrahedrally bonded carbon. The information is formed by a changeable ratio of hexagonally bonded carbon and tetrahedrally bonded carbon.
1. An information storage element, comprising:
a non-graphitic disordered carbon arrangement comprising a plurality of alternatingly arranged non-graphitic disordered carbon layers, wherein at least a first layer is formed in a first short-range order having a first ratio of sp 2 hybridized carbon and sp 3 hybridized carbon and at least a second layer is formed in a second short-range order having a second ratio of sp 2 hybridized carbon and sp 3 hybridized carbon, wherein the ratios are reversibly changeable.
2. The information storage element of claim 1 , wherein the arrangement is substantially free of nitrogen.
3. The information storage element of claim 1 , wherein the arrangement comprises a carbon layer or at least one carbon nanotube.
4. The information storage element of claim 3 , wherein the arrangement comprises a carbon nanotube, and the carbon nanotube has a length of approximately one nm to several hundred nanometers.
5. The information storage element of 1 , wherein the arrangement may have an arbitrary number of first and second layers.
6. The information storage element of 1 , wherein the first layer has a conductivity of approximately 10 4 Ωcm.
7. The information storage element of 1 , wherein the arrangement has a total thickness in the range of about 20 nm to about 120 nm.
8. The information storage element of 1 , wherein the arrangement has a total thickness in the range of about 30 nm to about 80 nm.
9. The information storage element of 1 , wherein the arrangement has a total thickness of about 40 nm.
10. The information storage element of claim 1 , wherein the first short-range order and the second short-range order have substantially the same chemical composition.
11. The information storage element of claim 1 , wherein the first short-range order and the second short-range order have different electrical properties.
12. The information storage element of claim 11 , wherein the electrical properties comprise electrical resistance of the arrangement.
13. The information storage element as claimed in claim 1 , wherein the second layer the portion of sp 3 hybridized carbon is increased.
14. The information storage element as claimed in claim 1 , wherein the arrangement further comprises a first graphite-like layer on one distal end portion of the arrangement.
15. The information storage element as claimed in claim 1 , wherein the arrangement further comprises a first diamond-like layer on one distal end portion of the arrangement.
16. The information storage element as claimed in claim 14 wherein the arrangement further comprises a top layer on a second distal end portion of the arrangement, the second distal end portion opposing the one distal end portion, wherein the top layer is either diamond-like or graphite-like.
17. The information storage element as claimed in claim 15 , wherein the arrangement further comprises a top layer on a second distal end portion of the arrangement, the second distal end portion opposing the one distal end portion, wherein the top layer is either diamond-like or graphite-like.
18. The information storage element as claimed in claim 1 , further comprising at least one graphite-like layer.
19. The information storage element as claimed in claim 18 , wherein the arrangement may have an arbitrary number of first, second, and graphite-like layers.
20. An information storage array, comprising a plurality of information storage cells, each information storage cell comprising:
an information storage element comprising a non-graphitic disordered carbon arrangement comprising a plurality of alternatingly arranged non-graphitic disordered carbon layers, wherein at least a first layer is formed in a first short-range order having a first ratio of sp 2 hybridized carbon and sp 3 hybridized carbon and at least a second layer is formed in a second short-range order having a second ratio of sp 2 hybridized carbon and sp 3 hybridized carbon, wherein the ratios are reversibly changeable; and a selection unit individually selecting the information storage element within the information storage array.
21. The information storage array of claim 20 , further comprising:
at least one first control line; and at least one second control line; wherein each information storage cell is arranged between a respective first control line and a respective second control line.
22. The information storage array of claim 21 , wherein the selection unit comprises at least one selection diode, the selection diode being arranged between a respective first control line and a respective second control line.
23. The information storage array of claim 20 , wherein the selection unit comprises at least one selection diode or at least one selection transistor.
24. A method of operating an information storage element, the information storage element a non-graphitic disordered carbon arrangement comprising a plurality of alternatingly arranged non-graphitic disordered carbon layers, wherein at least a first layer is formed in a first short-range order having a first ratio of sp 2 hybridized carbon and sp 3 hybridized carbon and at least a second layer is formed in a second short-range order having a second ratio of sp 2 hybridized carbon and sp 3 hybridized carbon, wherein the ratios are reversibly changeable, the method comprising:
changing the first ratio and the second ratio, thereby changing the information storage status of the information storage element.