The award will run from September 14th, 2007 to September 30th, 2008.
Research Abstract - New porphyrin-based charge-storage materials will be synthesized (Lindsey lab, NCSU) for attachment to electroactive surfaces in nanodevices as required for molecular-based information storage. Novel approaches for development of charge-transfer layers also will be investigated. Molecular-based charge-storage materials will be incorporated into a variety of novel solid-state nanodevices including S/MMM and MIMM junctions (Misra lab, NCSU). Of particular interest are strategies that prevent shorting of via metal penetration of the molecular layer. These routes involve (i) slow deposition of metals, (ii) selective deposition of metals, (iii) and functionalization of the porphyrinic molecules for specific reaction with the metal overlayer.
The Misra lab will explore MIMM junctions as an alternate testbed for molecular electronics. Studies of these structures include time-resolved methods such as pulse measurements to obtain speed response, particularly to elucidate the role of varying dielectric thickness. Frequency dispersion of capacitance will be correlated to charging and discharging of the molecular layer in the MIMM devices. The Misra lab also will place the two terminal MIMM junctions on MOSFET channels to interrogate the impact of redox states on channel current. Such studies will complement physical analysis at UC Riverside such as angle resolved XPS and IR with ultrathin top metals to gauge bonding to the molecules at various buried interfaces. The synthesis of new compounds is an integral part of this effort. In this regard, the Lindsey lab will design and synthesize novel molecules that have more complex features for use in MIMM devices, including multiple states and tethers on both sides of the molecule. The presence of tethers, either identical or exhibiting orthogonal reactivity (for selective, vectorial attachment to chemically distinct surfaces) enables the molecules to be attached to both surfaces of the MIMM device.
Material samples will be delivered from the Lindsey lab to collaborators (David Bocian, UC Riverside; Veena Misra, NCSU ECE) on a regular basis for physical studies. Results from the characterization studies will guide the synthesis efforts. The collaborative effort of the three groups will lead to new insights in molecular information storage. The Misra and Lindsey labs at N. C. State University will split equally the funds allocated to our labs.