1. Carbon Nanotube Memory Ricky Taing

2. Outline Motivation for NRAM Comparison of Memory NRAM Technology Carbon Nanotubes Device Operation Evaluation Current State of NRAM Fabrication Conclusions

3. Motivations and Goals Physical limitations of current memory Threshold voltage scaling, soft error Low power for mobile devices Universal memory Fast, dense, non-volatile, low energy

4. Comparison - Current Tech Size compared to DRAM Speed compared to SRAM Energy compared to Flash limited lifetime for flash

5. Comparison - Future Tech MRAM (Magnetic Memory) Insulator separated magnetic plates Changing polarity causes high or low resistance across insulator size limit being reached, larger than flash FRAM (Ferroelectric Memory) replace capacitor with Ferroelectric crystal in use unlimited writes smallest possible size larger than NRAM Josephson based

6. NRAM Technology Carbon Nanotubes cylindrical carbon molecules extremely strong (52x carbon steel) SWNT conductors composite fibers: 600 J/g to break 4x spider silk, 18x Kevlar fiber “Gecko strength” 200x as sticky

7. NRAM Technology

8. Device Overview

9. NRAM Technology On/Off States Potential Energy Van der Waals interactions Keeps state w/o current Threshold: 4.5V(on) and 20V(off)

10. NRAM

12. NRAM Technology Data Access OFF: high resistance ON: low resistance 100GHz operations for 10nm element

13. NRAM

14. NRAM Technology Calculations Stable at room temperature States hold for a variety of sizes Measurable resistance difference Bending force will not strain strain SWNT Small voltages Localized interactions

15. NRAM Technology Density 10^12 elements/cm^2 Speed current: 10x flash

16. Fabrication Work with fabrication companies Current tech Deposit nanotubes on chips Remove wrongly placed ones

17. Current State Nantero “ Made ground in the manufacturing process” Density 13 cm circular wafers - 10GB Future Space memory / BAE Problems? fabrication

18. Conclusion Stable, unlimited lifetime, instant on/standby, scalable “Universal” NRAM prototype devices in 2006