| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
Advances in Dielectric Materials and Electronic Devices
|
| Presentation Title |
Plasma-assisted Epitaxy and Piezoelectric Behavior of AlN Films on c-Sapphire |
| Author(s) |
Morton Greenslit, Robert Lad, Mauricio Pereira da Cunha |
| On-Site Speaker (Planned) |
Morton Greenslit |
| Abstract Scope |
AlN films offer advantages compared to piezoelectric single crystal substrates for use in Surface Acoustic Wave (SAW) sensor devices, including flexible SAW device configurations, higher operating frequencies, and high temperature performance up to 800oC. In this work, a plasma-assisted epitaxy method is presented to achieve high quality AlN (0002) films on c-sapphire using e-beam evaporation of Al in an RF nitrogen plasma at a growth temperature of 930oC. A pre-nitridation treatment of sapphire was found to be beneficial in creating a seed layer for AlN epitaxy. RHEED analysis and XRD pole figures indicate that (0002) AlN grains also have in-plane registry with the sapphire substrate. SAW resonator devices operating near 450 MHz with different transducer and reflector configurations were patterned on the AlN/sapphire films. Admittance and impedance plots determined from S11 measurements indicate that defects and oxygen impurities in the AlN films strongly influence overall SAW resonator performance. |