VACUUM DEPOSITION OF AlN ACOUSTIC TRANSDUCERS

Abstract

Thin-film microwave acoustic transducers of piezoelectric aluminum nitride (AlN) have been vacuum deposited by two methods. Aluminum nitride was deposited on metallic film substrates at 300°–1200°C by evaporating aluminum in the presence of either nitrogen gas dissociated in an ac discharge or in the presence of ammonia gas. Longitudinal ultrasonic waves were generated in a sapphire rod with a one-way-tuned conversion loss of 10 dB at 1700 MHz.

Dielectrical properties of metal-insulator-metal aluminum nitride structures: Measurement and modeling

“…1,2 On the other hand, the AlN offers additional outstanding physical properties of great interest for a large range of applications: its hardness, high thermal conductivity, high-temperature, and caustic chemical resistance make of this material an attractive challenger for electronic packaging applications. 3,4 Furthermore, its low interface state density properties and its wide direct band gap 4,5 invite to investigate its potential as an insulating material for semiconductor devices and let envisage promising applications in domains such as memory devices.…”

Memory effect of Al-rich AlN films synthesized with rf magnetron sputtering

“…Aluminum nitride ͑AlN͒ film has attracted significant interest due to its various applications such as surface acoustic wave ͑SAW͒ devices and light-emitting applications. [1][2][3][4][5] AlN thin film can be deposited with a number of techniques such as reactive evaporation, magnetron sputtering, pulsed laser deposition, and hybrid techniques such as plasma-or ionassisted depositions. [6][7][8] With its high thermal conductivity, 9 reasonable thermal match to semiconductors ͑such as Si, GaAs, and GaN͒ and small lattice mismatch 9,10 and wide band gap ͑6.2 eV͒, 4 AlN thin film could be used as a gate dielectric for field-effect transistors.…”

Molecular Beam Epitaxy of Nitrides for Advanced Electronic Materials

“…Wauk and Winslow [156] vacuum deposited AlN from 400 to 1100 C substrate temperature comparing N 2 with a plasma discharge and NH 3 without a plasma discharge for application as piezoelectric acoustic resonators. Wauk and Winslow [156] vacuum deposited AlN from 400 to 1100 C substrate temperature comparing N 2 with a plasma discharge and NH 3 without a plasma discharge for application as piezoelectric acoustic resonators.…”