ELLIPTICAL STRUCTURE FOR BULK ACOUSTIC WAVE RESONATOR
An elliptical-shaped resonator device. The device includes a bottom metal plate, a piezoelectric layer overlying the bottom metal plate, and a top metal plate overlying the piezoelectric layer. The top metal plate, the piezoelectric layer, and the bottom metal plate are characterized by an elliptical shape having a horizontal diameter (dx) and a vertical diameter (dy), which can be represented as ellipse ratio R=dx/dy. Using the elliptical structure, the resulting bulk acoustic wave resonator (BAWR) can exhibit equivalent or improved insertion loss, higher coupling coefficient, and higher quality factor compared to conventional polygon-shaped resonators.
1 . An elliptical-shaped resonator circuit device, the device comprising:
a substrate
a piezoelectric layer overlying the substrate, the piezoelectric layer having a micro-via;
a bottom metal plate underlying the piezoelectric layer;
a backside metal interconnect underlying the piezoelectric layer and coupled to the bottom metal plate;
a top metal plate overlying the piezoelectric layer; and
a topside metal interconnect overlying the piezoelectric layer and coupled to the backside metal interconnect through the micro-via;
wherein the top metal plate, the piezoelectric layer, and the bottom metal plate are characterized by an elliptical shape having a horizontal diameter (dx) and a vertical diameter (dy), which can be represented as ellipse ratio R=dx/dy.
2 . The device of claim 1 wherein the ellipse ratio R ranges from about 1.20 to about 2.0.
3 . The device of claim 1 wherein the bottom metal plate and top metal plate include molybdenum (Mo), ruthenium (Ru), or tungsten (W), Aluminum-Copper (AlCu).
4 . The device of claim 1 wherein the piezoelectric layer includes materials or alloys having at least one of the following: AlN, AlGaN, GaN, InN, InGaN, AlInN, AlInGaN, ScAlN, ScGaN, AlScYN, and BN.
5 . The device of claim 1 further comprising one or more pillar-type energy confinement features (ECFs) coupled to the top metal plate or the bottom metal plate; wherein the one or more pillar-type ECFs comprises a dielectric material, a metal material, or a combination of dielectric and metal materials.
6 . The device of claim 1 further comprising one or more cavity-type energy confinement features (ECFs) configured within the top metal plate or the bottom metal plate.
7 . An RF filter circuit device, the device comprising:
a substrate member;
a dielectric passivation layer overlying the substrate member;
a plurality of elliptical-shaped resonator devices overlying the substrate member and configured within the dielectric passivation layer, each of the elliptical shaped resonators comprising
a piezoelectric layer overlying the bottom metal plate, the piezoelectric layer having a micro-via;
a bottom metal plate underlying the piezoelectric layer;
a backside metal interconnect underlying the piezoelectric layer and coupled to the bottom metal plate;
a top metal plate overlying the piezoelectric layer; and
a topside metal interconnect overlying the piezoelectric layer and coupled to the backside metal interconnect through the micro-via;
wherein the top metal plate, the piezoelectric layer, and the bottom metal plate are characterized by an elliptical shape having a horizontal diameter (dx) and a vertical diameter (dy), which can be represented as ellipse ratio R=dx/dy; and
wherein each of the plurality of elliptical-shaped resonator devices is coupled to at least one other resonator in the plurality of elliptical-shaped resonator devices.
8 . The device of claim 7 wherein the ellipse ratio R ranges from about 1.20 to about 2.00.
9 . The device of claim 7 wherein the substrate member is selected from a silicon substrate, a sapphire substrate, silicon carbide substrate, a GaN bulk substrate, a GaN template, an AlN bulk substrate, an AlN template, Al x Ga 1-x N templates, engineered substrates such as silicon on insulator (SOI), and polycrystalline AlN templates.
10 . The device of claim 7 wherein the dielectric passivation layer includes silicon oxide, silicon nitride, aluminum nitride, or aluminum oxide materials.
11 . The device of claim 7 wherein the bottom metal plate and top metal plate include molybdenum (Mo), ruthenium (Ru), tungsten (W), or Aluminum Copper (AlCu) materials.
12 . The device of claim 7 wherein the piezoelectric layer includes materials or alloys having at least one of the following: AlN, AlGaN, GaN, InN, InGaN, AlInN, AlInGaN, ScAlN, ScGaN, AlScYN, and BN.
13 . The device of claim 7 wherein the micro-via includes molybdenum (Mo), ruthenium (Ru), tungsten (W), or Aluminum Copper (AlCu) materials.
14 . The device of claim 7 further comprising one or more pillar-type energy confinement features (ECFs) coupled to the top metal plate or the bottom metal plate; wherein the one or more pillar-type ECFs comprises a dielectric material, a metal material, or a combination of dielectric and metal materials.
15 . The device of claim 7 further comprising one or more cavity-type energy confinement features (ECFs) configured within the top metal plate or the bottom metal plate.
16 . An RF filter circuit device, the device comprising:
a substrate member;
a dielectric passivation layer overlying the substrate member;
a plurality of elliptical-shaped resonator devices overlying the substrate member and configured within the dielectric passivation layer, each of the elliptical shaped resonators comprising
a piezoelectric layer overlying the bottom metal plate, the piezoelectric layer having a micro-via;
a bottom metal plate underlying the piezoelectric layer;
a backside metal interconnect underlying the piezoelectric layer and coupled to the bottom metal plate;
a top metal plate overlying the piezoelectric layer;
a topside metal interconnect overlying the piezoelectric layer and coupled to the backside metal interconnect through the micro-via;
one or more pillar-type energy confinement features (ECFs) coupled to the top metal plate or the bottom metal plate, wherein the one or more pillar-type ECFs comprises a dielectric material, a metal material, or a combination of dielectric and metal materials; and
one or more cavity-type energy confinement features (ECFs) configured within the top metal plate or the bottom metal plate;
wherein the top metal plate, the piezoelectric layer, and the bottom metal plate are characterized by an elliptical shape having a horizontal diameter (dx) and a vertical diameter (dy), which can be represented as ellipse ratio R=dx/dy; and
wherein each of the plurality of elliptical-shaped resonator devices is coupled to at least one other resonator in the plurality of elliptical-shaped resonator devices.
17 . The device of claim 16 wherein the ellipse ratio R ranges from about 1.20 to about 2.00.
18 . The device of claim 16 wherein the substrate member is selected from a silicon substrate, a sapphire substrate, silicon carbide substrate, a GaN bulk substrate, a GaN template, an AlN bulk substrate, an AlN template, Al x Ga 1-x N templates, engineered substrates such as silicon on insulator (SOI), and polycrystalline AlN templates; and
wherein the dielectric passivation layer includes silicon oxide, silicon nitride, aluminum nitride, or aluminum oxide materials.
19 . The device of claim 16 wherein the bottom metal plate and top metal plate include molybdenum (Mo), ruthenium (Ru), tungsten (W), or Aluminum Copper (AlCu) materials;
wherein the piezoelectric layer includes materials or alloys having at least one of the following: AlN, AlGaN, GaN, InN, InGaN, AlInN, AlInGaN, ScAlN, ScGaN, AlScYN, and BN; and
wherein the micro-via includes molybdenum (Mo), ruthenium (Ru), tungsten (W), or Aluminum Copper (AlCu) materials.
20 . The device of claim 16 wherein the piezoelectric layer includes materials or alloys having at least one of the following: AlN, AlGaN, GaN, InN, InGaN, AlInN, AlInGaN, ScAlN, ScGaN, AlScYN, and BN.