Solution-Processed Flexible Memory Devices Dr. Nadine Gergel-Hackett Dr. Behrang Hamadani Dr. Curt Richter Dr. David Gundlach

Technology Completed design and fabrication of electronic memory devices on inexpensive plastic substrates actual devices Motivation Flexible electronics is an emerging industry that “sprays” electronic devices onto inexpensive plastic sheets (like inkjet printer on an overhead transparency) Problem: Currently no method exists in flexible electronics for fabricating non-volatile low operation voltage memory devices ie devices that “hold” written state without an applied voltage

Commercial Applications Flexible memory devices would have applications in almost all flexible electronics circuits, some possible uses of flexible electronics include: sensor pack power supply processor & RFID communication Memory in display Sensor Tape – J. Ricklin/DARPA Integrated Sensor is Structure – T. Clark/DARPA

Technology - Combining separate existing technologies Advantages of Method of Device Fabrication: Can be performed at room temperature and pressure Simplified design Inexpensive fabrication procedures (a) Contact Flexible Substrate Sol gel TiO2 using sol gel to make TiO2 using TiO2 in memory device to invent a method for making sol gel TiO2-based flexible memory device actual devices

Technology Devices showed an electrical switching with memory behavior Electrical characteristics of device

Technology Applications Areas for Improvement: “write” and “erase” voltage values, and on/off ratios vary between devices, and increase with operation Devices switched maximum of <10 times before permanently remaining in high state Source of electrical switching behavior not yet well studied 1 2 3 4 5 6

Technology Applications

Potential Applications :The Missing Piece for the Realization of Flexible Electronics Sensors Display Logic (computing) Memory (Low Power, Re-Writeable)

Licensing & Collaboration Opportunity “Solution-Processed Flexible Titanium Dioxide Memory Devices” Provisional patent application filed 1/22/08 serial # 51/022,534

Contact Information Nadine Gergel-Hackett, Ph.D 301-975-8755 nadinegh@nist.gov David Gundlach, Ph.D 301-975-2048 david.gundlach@nist.gov Curt Richter, Ph.D. 301-975-2082 curt.richter@nist.gov