| AVS 56th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology | Monday Sessions |
| Session NS+BI-MoM |
| Session: | Nanowires and Nanoparticles I |
| Presenter: | R. Subramanian, University of Texas at Arlington |
| Authors: | R. Subramanian, University of Texas at Arlington P. Bhadrachalam, University of Texas at Arlington V. Ray, University of Texas at Arlington S.J. Koh, University of Texas at Arlington |
| Correspondent: | Click to Email |
Semiconducting nanoparticles are increasingly finding innovative applications in many areas of science and technology such as bio-medicine, solar-energy harvesting, and photonics. For effective use of nanoparticles for these applications, it is necessary to know their electronic structures and efficient and accurate techniques to measure them are desired. We present a new technique to directly probe the energy levels of individual semiconducting nanoparticles in which the units to measure the electronic structures are fabricated using CMOS-compatible processes. This technique not only enables us to probe energy levels of an individual nanoparticle, but allows carrying out many such measurements from numerous units fabricated with a single-batch parallel processing. The energy levels were directly obtained with the I-V measurement through double barrier tunnel junctions that were formed when the nanoparticles were placed between vertically separated source and drain electrodes. The band gap (Eg~1.92eV) and energy level spacings (ΔE ~ 130meV, ΔEp-d~ 96meV and ΔEd-f~ 103meV) were measured directly from the current-voltage and differential conductance spectra for colloidal CdSe nanoparticles (~7nm). Measurements for core-shell semiconducting nanoparticles (such as InP/ZnS) will also be presented. (Supported by NSF CAREER (ECS-0449958), ONR (N00014-05-1-0030), and THECB ARP (003656-0014-2006))