| AVS 55th International Symposium & Exhibition | |
| Thin Film | Thursday Sessions |
| Session TF-ThM |
| Session: | Evaporation, Pulsed Laser Deposition, and Molecular Beam Epitaxy |
| Presenter: | S.V.N.T. Kuchibhatla, Pacific Northwest National Laboratory |
| Authors: | S.V.N.T. Kuchibhatla, Pacific Northwest National Laboratory Z.Q. Yu, Nanjing Normal University, China S. Thevuthasan, Pacific Northwest National Laboratory P. Nachimuthu, Pacific Northwest National Laboratory V. Shutthanandan, Pacific Northwest National Laboratory C.M. Wang, Pacific Northwest National Laboratory Y. Li, Pacific Northwest National Laboratory C.H. Henager, Jr., Pacific Northwest National Laboratory S.K. Sundaram, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
Growth of electronic materials as single crystals for a variety of uses can be limited by the lack of fundamental understanding of the nucleation, growth, and coalescence regime at the initial stages of the growth process. As a first step in comprehensively developing a knowledge database on the nucleation and growth of various materials, we have investigated the growth of cuprous oxide (Cu2O) nanoclusters on SrTiO3(100) substrate. There has been considerable interest in Cu2O nanoclusters because they can be used effectively in chemical and photochemical applications due to their unique electronic transport properties. We have grown Cu2O clusters using oxygen plasma assisted molecular beam epitaxy (OPA-MBE) and the effects of deposition rate, substrate temperature, oxygen pressure, and deposition time were systematically studied. Structural, morphological, and chemical properties of these clusters were investigated using several surface and bulk interrogation methods. X-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) measurements clearly demonstrated the complex nature of the copper oxide system due to the possibility of co-existing Cu(0), Cu(1), and Cu(2) phases in the clusters. Optimum deposition conditions were established to produce pure Cu2O clusters. Atomic force microscopy (AFM) images clearly showed the growth of uniformly distributed epitaxial, faceted pure Cu2O clusters on STO (100) with (100) orientation. Rutherford backscattering spectrometry (RBS) measurements have been used along with the AFM and transmission electron microscopy (TEM) measurements to compute the thickness of the films. The cluster size, shape and their preferred orientation were critically analyzed. It is observed that the surface morphology, cluster coalescence, and film formation are highly dependent on various growth parameters including growth rate, deposition temperature, and deposition time. Theoretical investigations have also been carried out to understand growth mechanisms and these results will be presented along with the experimental observations.