title: Determination of mass density, dielectric, elastic, and piezoelectric constants of bulk GaN crystal.
abstract: Mass density, dielectric, elastic, and piezoelectric constants of bulk GaN crystal were determined. Mass density was obtained from the measured ratio of mass to volume of a cuboid. The dielectric constants were determined from the measured capacitances of an interdigital transducer (IDT) deposited on a Z-cut plate and from a parallel plate capacitor fabricated from this plate. The elastic and piezoelectric constants were determined by comparing the measured and calculated SAW velocities and electromechanical coupling coefficients on the Z- and X-cut plates. The following new constants were obtained: mass density p = 5986 kg/m(3); relative dielectric constants (at constant strain S) ε(S)(11)/ε(0) = 8.6 and ε(S)(11)/ε(0) = 10.5, where ε(0) is a dielectric constant of free space; elastic constants (at constant electric field E) C(E)(11) = 349.7, C(E)(12) = 128.1, C(E)(13) = 129.4, C(E)(33) = 430.3, and C(E)(44) = 96.5 GPa; and piezoelectric constants e(33) = 0.84, e(31) = -0.47, and e(15) = -0.41 C/m(2).
authors.affiliation: Institute of Electronic Materials Technology, Warsaw, Poland. waldemar.soluch@itme.edu.pl
authors.forename: Waldemar
authors.initials: W
authors.lastname: Soluch
authors.forename: Ernest
authors.initials: E
authors.lastname: Brzozowski
authors.forename: Magdalena
authors.initials: M
authors.lastname: Lysakowska
authors.forename: Jolanta
authors.initials: J
authors.lastname: Sadura
mesh_terms: D003198:Computer Simulation; D003460:Crystallization; D003720:Densitometry / Q000379:methods*; D055119:Elastic Modulus; D017097:Electric Impedance; D005708:Gallium / Q000737:chemistry*; D008422:Materials Testing; D008956:Models, Chemical; D014732:Vibration
chemical_list: C473348:gallium nitride; D005708:Gallium