Dense arrays and charge storage devices
View Patent ↗There is provided a monolithic three dimensional array of charge storage devices which includes a plurality of device levels, wherein at least one surface between two successive device levels is planarized by chemical mechanical polishing.
1. A memory device, comprising:
a silicon substrate;
a first vertical channel located over the silicon substrate;
a second vertical channel located horizontally adjacent to the first vertical channel in a first row over the silicon substrate;
a third vertical channel located horizontally adjacent to the first vertical channel in a second row different from the first row over the silicon substrate;
contacts coupling to the first vertical channel;
contacts coupling to the second vertical channel;
contacts coupling to the third vertical channel;
a first charge storage region located adjacent to a first portion of the first vertical channel;
a first control gate located adjacent to the first charge storage region;
a second charge storage region located adjacent to a second portion of the first vertical channel above the first portion of the first vertical channel; and
a second control gate located adjacent to the second charge storage region;
wherein the first charge storage region and the second charge storage region comprise a continuous charge storage dielectric film and a continuous tunneling dielectric located between the first vertical channel and both the first and the second control gates; and
wherein the first control gate is shared between the first vertical channel, the second vertical channel and the third vertical channel; and
driver circuitry associated with the operation of said memory device.
2. The memory device of claim 1 , wherein the device comprises a monolithic three dimensional array of charge storage devices comprising a plurality of device levels.
3. The memory device of claim 1 , wherein the contacts coupling to the first vertical channel comprise a first contact which couples to a lower portion of the first vertical channel and a second contact which couples to an upper portion of the first vertical channel.
4. The memory device of claim 3 , wherein the first and the second control gates are located above the first contact and below the second contact.
5. The memory device of claim 1 , wherein the second control gate is located above the first control gate.
6. The memory device of claim 5 , further comprising an insulating layer which is located between the first and the second control gates and electrically isolates the first control gate from the second control gate.
7. The memory device of claim 1 , wherein the first charge storage region and the second charge storage region further comprise a control gate dielectric located between both the first and the second control gates and the continuous charge storage dielectric film.
8. The memory device of claim 7 , wherein the continuous charge storage dielectric film comprises a silicon nitride dielectric film or an insulating layer containing conductive nanocrystals.
9. The memory device of claim 7 , wherein:
the continuous tunneling dielectric comprises a first oxide layer;
the continuous charge storage dielectric film comprises a silicon nitride layer; and
the control gate dielectric comprises a second oxide layer;
the first charge storage region comprises a first portion of the first oxide layer located adjacent to a first portion of the first vertical channel, a first portion of the silicon nitride layer located adjacent to the first portion of the first oxide layer, and a first portion of the second oxide layer located adjacent to the first portion of the silicon nitride layer; and
the second charge storage region comprises a second portion of the first oxide layer located adjacent to a second portion of the first vertical channel, a second portion of the silicon nitride layer located adjacent to the second portion of the first oxide layer, and a second portion of the second oxide layer located adjacent to the second portion of the silicon nitride layer; and
the driver circuitry is at least partially in the silicon substrate and below the first and the second vertical channels.
10. The memory device of claim 1 , wherein the first vertical channel comprises a first semiconductor containing pillar, the second vertical channel comprises a second semiconductor containing pillar, and the third vertical channel comprises a third semiconductor containing pillar.
11. The memory device of claim 10 , wherein the first control gate is located between the first semiconductor containing pillar, the second semiconductor containing pillar and the third semiconductor containing pillar.
12. The memory device of claim 11 , wherein:
the memory device further comprises a plurality of horizontally separated vertical channels comprising a plurality of horizontally separated semiconductor containing pillars;
the first control gate is shared between the plurality of horizontally separated semiconductor containing pillars; and
the first control gate is located between the plurality of horizontally separated semiconductor containing pillars.
13. The memory device of claim 12 , wherein:
the plurality of horizontally separated vertical channels comprise a three by three array of horizontally separated semiconductor containing pillars;
the first control gate is shared between the three by three array of horizontally separated semiconductor containing pillars; and
the first control gate is located between the horizontally separated semiconductor containing pillars of the three by three array of horizontally separated semiconductor containing pillars.
14. The memory device of claim 12 , wherein the plurality of horizontally separated semiconductor containing pillars each have a substantially circular shape when viewed from above.
15. The memory device of claim 10 , wherein the first vertical channel comprises a first silicon containing pillar, the second vertical channel comprises a second silicon containing pillar, and the third vertical channel comprises a third silicon containing pillar.
16. A monolithic three dimensional array of charge storage devices comprising a plurality of device levels, comprising:
a silicon substrate;
a plurality of horizontally separated vertical semiconductor containing channels arranged in a plurality of rows;
a first control gate which is shared between at least two of the plurality of horizontally separated vertical semiconductor containing channels located in a first row of the plurality of rows and between at least two of the plurality of horizontally separated vertical semiconductor containing channels located in different rows of the plurality of rows;
a second control gate which is shared between at least two of the plurality of horizontally separated vertical semiconductor containing channels located in the first row and between at least two of the plurality of horizontally separated vertical semiconductor containing channels located in the different rows, wherein the second control gate is located above the first control gate; and
a charge storage region located between a first one of the plurality of horizontally separated semiconductor containing channels and the first and the second control gates; and
driver circuitry associated with the operation of said array of charge storage devices.
17. The monolithic three dimensional array of claim 16 , wherein:
the first control gate is located between the plurality of horizontally separated semiconductor containing channels;
the second control gate is located between the plurality of horizontally separated semiconductor containing channels; and
the charge storage region comprises a continuous layer or film located between at least the first one of the plurality of semiconductor containing channels and both the first and the second control gates.
18. The monolithic three dimensional array of claim 17 , wherein the charge storage region comprises a silicon nitride dielectric film or an insulating layer containing conductive nanocrystals.
19. The monolithic three dimensional array of claim 17 , wherein the charge storage region comprises a first oxide layer located adjacent to a first portion of a first vertical semiconductor containing channel, a nitride located adjacent to the first oxide layer, and a second layer located adjacent to the nitride charge storage layer.
20. The monolithic three dimensional array of claim 19 , wherein the tunneling dielectric comprises a continuous tunneling dielectric located between at least the first one of the plurality of semiconductor containing channels and both the first and the second control gates.
21. The monolithic three dimensional array of claim 16 , wherein the charge storage region comprises a floating gate.
22. The monolithic three dimensional array of claim 16 , wherein each of the plurality of semiconductor containing channels comprises a respective first contact which couples to a lower portion of the semiconductor containing channel and a respective second contact which couples to an upper portion of the semiconductor containing channel.
23. The monolithic three dimensional array of claim 16 , further comprising an insulating layer which is located between the first and the second control gates and electrically isolates the first control gate from the second control gate.
24. The monolithic three dimensional array of claim 16 , wherein:
the plurality of horizontally separated vertical semiconductor containing channels comprise a three by three array of horizontally separated vertical semiconductor containing channels;
the first control gate is shared between the three by three array of horizontally separated vertical semiconductor containing channels; and
the first control gate is located between the horizontally separated vertical semiconductor containing channels of the three by three array of horizontally separated vertical semiconductor containing channels.
25. The monolithic three dimensional array of claim 16 , wherein the plurality of horizontally separated vertical semiconductor containing channels each have a substantially circular shape when viewed from above.
26. The monolithic three dimensional array of claim 19 , wherein the plurality of horizontally separated vertical semiconductor containing channels each have a substantially circular shape when viewed from above.