| AVS 56th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology | Tuesday Sessions |
| Session NS-TuP |
| Session: | Nanometer-scale Science and Technology Poster Session |
| Presenter: | K.T. Kim, University at Buffalo |
| Authors: | K.T. Kim, University at Buffalo G.H. Kim, University at Buffalo Y.-K. Yoon, University at Buffalo |
| Correspondent: | Click to Email |
Recently, ZnO nanowires (NWs) have been extensively studied for solar cell and field-effect transistor applications because of their intrinsic n-type semiconductor property with a wide band gap of 3.36 eV and a large exciton binding energy of 60 meV[1]. Specially, the nanowire architecture in field-effect transistors provides many advantages against the conventional bulk substrate approach such as device size reduction, isolated channel, reduced leakage current, reduced control voltage, and reduced power consumption even to several nJ[2]. The ZnO nanowire based transistor can be extended to a non-volatile memory device by adopting ferroelectric materials for the gate dielectric layer. While Bi-based perovskite Bi3.25La0.75Ti3O12 (BLT) and Pb(Zr,Ti)O3 (PZT) thin films have been extensively investigated for non-volatile ferroelectric random access memory (FRAM) devices, BLT based devices are reported to offer better fatigue resistant characteristic, low processing temperature, and large remnant polarization.
In this study, we show a process to make ZnO nanowires using electrospinning with the polymer ZnO nanocomposite and subsequent sintering in various temperatures and characterize them. Also, BLT is prepared by the metal organic deposition (MOD) process and is spincoated on a Pt(150nm)/Ti(50nm)/SiO2/Si substrate, followed by sintering in different temperatures (550°C, 600°C, 650°C, and 700°C) to form crystalline perovskite structures [3]. And the ZnO nanowires are formed on the BLT ferroelectric gate and the electrodes for source and drain are defined using a UV lithography followed by metallization. We show non-volatile switching in ZnO NWs with the BLT ferroelectric gate. We also evaluate the field dependent conduction of ZnO NWs with the remnant field of ferroelectric thin films and show fatigue and retention free performance. These devices are useful not only for non-volatile memory devices but also for various biosensors and nanoelectromechanical systems.
[1] B. Sun, and H. Sirringhaus, Nano Lett., 5, 2408( 2005)
[2] X. Duan, Y. Huang, and C. M. Lieber, 2, Nano Letters, 487 ( 2002)
[3] Kyoung-Tae Kim, Chang-Il Kim, Yong-Kyu Yoon, “ Characteristics of La-substituted Bismuth Titanate Ferroelectric Nanofibers by Electrospinning ”AVS 55th Inter. Symp. Boston, USA (October 19-24, 2008)