PIEZOELECTRIC MATERIAL AND PIEZOELECTROC DEVICE
Piezoelectric nitride compound materials with improved properties is provided. The piezoelectric material comprises aluminium, nitrogen and ternary and quaternary dopants that can be selected from calcium, ruthenium, boron and/or yttrium.
1 . A piezoelectric material, comprising:
Al 1-x [(Ca a , Ru b , Z1 c1 , Z2 c2 ) y ] x N as its main constituent, wherein:
0.055≤a≤1.33,
0.055≤b≤1.33,
0≤c1,
0≤c2,
0≤c=c1+c2≤1.33,
y=1/(a+b+c),
0.03≤x≤0.75 and
Z1 and Z2 are selected from B and Y.
2 . The piezoelectric material of claim 1 , wherein the main constituent is Al 1-x [(Ca a , Ru b , Z1 c1 , Z2 c2 ) y ] x N and Z1 and Z2 is selected from B and Y or only B or only Y, and wherein:
0.165≤a≤0.66,
0.165≤b≤0.66,
0≤c1,
0≤c2,
0≤c=c1+c2≤0.66,
y=1/(a+b+c), and
0.09≤x≤0.372.
3 . The piezoelectric material of claim 1 , wherein x is selected from 0.03, 0.06, 0.09, 0.12, 0.15, 0.18, 0.21, 0.24, 0.27, 0.30, 0.33, 0.36, 0.39, 0.42, 0.45, 0.48, 0.51, 0.54, 0.57, 0.60, 0.63, 0.66, 0.69, 0.72 and 0.75.
4 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.814 Ca 0.062 Ru 0.062 B 0.062 N.
5 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.814 Ca 0.062 Ru 0.062 B 0.124 N.
6 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.876 Ca 0.062 Ru 0.062 B 0.124 N.
7 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.69 Ca 0.124 Ru 0.124 B 0.062 N.
8 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.814 Ca 0.062 Ru 0.062 Y 0.062 N.
9 . The piezoelectric material of claim 1 , wherein the main constituent is Al 0.876 Ca 0.062 Ru 0.062 N.
10 . The piezoelectric material of claim 1 , wherein 44.2 (atomic %), 53.5 (atomic %), 62.77 (atomic %), 72.1 (atomic %), 81.4 (atomic %), 90.7 (atomic %), 95.78 (atomic %), 98.25 (atomic %) or 99 (atomic %) are Al while the remaining balance is a combination of ternary or quaternary doped AlN piezoelectric material containing Ca (calcium), Ru (ruthenium), B (boron) and Y (yttrium).
11 . The piezoelectric material of claim 1 , wherein the piezoelectric material is part of a piezoelectric device.
12 . The piezoelectric material of claim 11 , the piezoelectric device being selected from:
an electro acoustic resonator, a SAW resonator, a SAW filter, a solidly mounted resonator (SMR-type resonator), a (SMR-)BAW filter, a guided BAW (GBAW) resonator, a GBAW filter, a film bulk acoustic wave (FBAR) resonator, a FBAR filter, or
a resonator working with Lamb waves, acoustic plate waves (APW), Rayleigh SAW (R-SAW), Sezawa mode waves, shear-horizontal SAWs (SH-SAWs), Love mode waves, pseudo-surface acoustic waves (PSAW) or Leaky SAWs (LSAW), or
an acoustic device, a multiplexer, a duplexer, a quadplexer, a hexaplexer based on any of the above types of resonators, a piezoelectric generator, a piezoelectric sensor, a mass sensor, a microfluidic sensor, a piezoelectric transducer, an energy harvester, an ultrasound devices, a transducer, atransmitter, a piezo (MEMS) microphone, a device that utilizes direct or reverse piezolectric effect in a thin film or bulk ceramic form.