Title :
Study of ZnO thin films grown by PLD on (100) Si for surface acoustic wave devices
Author :
Chryssis, A.N. ; Krishnamoorthy, S. ; Iliadis, A.A. ; Lee, U.
Author_Institution :
Dept. of Electr. & Comput. Eng., Maryland Univ., College Park, MD, USA
Abstract :
ZnO thin films were deposited on Si (100) substrates using Pulsed Laser Deposition at 600 °C and an oxygen pressure of 1 e-4 Torr. Inorder to improve the ZnO film quality for SAW device applications, buffer layers of ZnO and ZnO/Indium Tin Oxide(ITO) alternating layers were grown on Si (100). High-resolution X-ray photoelectron spectroscopy (XPS) indicated a binding energy of Zn(2p3) at 1021.4 eV and O (1s) at 530.5 eV and ascertained the film composition. The quality of crystalline growth was determined using X-ray diffraction (XRD) and photoluminescence measurements. SAW filters having inter-digitated (IDT) finger widths of 1μm and finger spacing of 2.5 μm, were fabricated on films with different buffer layers. The input and output IDTs were composed of a 500 μm thick layer of Al, which was deposited using e-beam evaporation. Scanning electron microscopy (SEM) images of the SAW devices indicated the high quality photolithography. The center frequency of the SAW filters has been designed to be in the GHz range by improving ZnO film quality on Si (100) substrate, and the geometry and lithography of the device. The devices are capable of ultra high frequency response suitable for secure mobile communication systems and high performance sensors.
Keywords :
II-VI semiconductors; X-ray diffraction; X-ray photoelectron spectra; binding energy; mobile communication; photolithography; photoluminescence; pulsed laser deposition; scanning electron microscopy; semiconductor growth; semiconductor thin films; surface acoustic wave filters; zinc compounds; 1 micron; 1×10-4 torr; 2.5 micron; 500 micron; 600 degC; SAW device applications; SEM; Si; Si (100) substrate; Si substrate; X-ray diffraction; X-ray photoelectron spectroscopy; XPS; XRD; ZnO; ZnO thin films; binding energy; buffer layers; crystalline growth; e-beam evaporation; inter digitated finger widths; mobile communication systems; oxygen pressure; photolithography; photoluminescence measurements; pulsed laser deposition; scanning electron microscopy; sensors; surface acoustic wave devices; surface acoustic wave filters; Acoustic waves; Buffer layers; Pulsed laser deposition; SAW filters; Semiconductor films; Semiconductor thin films; Substrates; Surface acoustic wave devices; Thin film devices; Zinc oxide;
Conference_Titel :
Semiconductor Device Research Symposium, 2003 International
Print_ISBN :
0-7803-8139-4
DOI :
10.1109/ISDRS.2003.1272021
