Title :
Comments on "Epitaxially grown GaN thin-film SAW filter with high velocity and low insertion loss"
Author :
Woods, R.C. ; Boroumand, Farhad A.
Author_Institution :
Dept. of Electr. & Comput. Eng., Iowa State Univ., Ames, IA, USA
Abstract :
In 2001, Lee et al. (see ibid., vol.48, no.5, p.524-9, May 2001) proposed the use of GaN layers as a suitable material for surface-acoustic wave devices. They calculated the electromechanical coupling factor (k2) for this material to be (4.3±0.3)%. We have repeated their experiments and report a significantly lower value of k2=(0.066±0.003)% for a film thickness of ∼0.1 times the acoustic wavelength.
Keywords :
III-V semiconductors; gallium compounds; piezoelectric semiconductors; semiconductor epitaxial layers; surface acoustic wave filters; vapour phase epitaxial growth; wide band gap semiconductors; GaN; MOVPE; SAW filter; Smith chart; electromechanical coupling factor; epitaxial growth; high velocity; interdigital transducer; low insertion loss; surface-acoustic wave filter; thin-film; Acoustic devices; Acoustic materials; Gallium nitride; Insertion loss; Piezoelectric films; SAW filters; Surface acoustic wave devices; Surface acoustic waves; Surface morphology; Transistors; Coupling constant; GaN; Smith chart; gallium nitride; interdigital transducers (IDTs); network analyzer; piezoelectricity; surface-acoustic wave (SAW);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2005.860657
