Method of manufacture for single crystal capacitor dielectric for a resonance circuit
A method of manufacturing an integrated circuit. This method includes forming an epitaxial material comprising single crystal piezo material overlying a surface region of a substrate to a desired thickness and forming a trench region to form an exposed portion of the surface region through a pattern provided in the epitaxial material. Also, the method includes forming a topside landing pad metal and a first electrode member overlying a portion of the epitaxial material and a second electrode member overlying the topside landing pad metal. Furthermore, the method can include processing the backside of the substrate to form a backside trench region exposing a backside of the epitaxial material and the landing pad metal and forming a backside resonator metal material overlying the backside of the epitaxial material to couple to the second electrode member overlying the topside landing pad metal.
1 . An acoustic resonator device comprising:
a bulk substrate member, having a surface region, and a thickness of material, the bulk substrate having a first recessed region and a second recessed region, and a support member disposed between the first recessed region and the second recessed region;
a thickness of single crystal piezo material formed overlying the surface region, the thickness of single crystal piezo material having an exposed backside region configured with the first recessed region and a contact region configured with the second recessed region;
a first electrode member formed overlying an upper portion of the thickness of single crystal piezo material;
a second electrode member formed overlying a lower portion of the thickness of single crystal piezo material to sandwich the thickness of single crystal piezo material with the first electrode member and the second electrode member, the second electrode member extending from the lower portion that includes the exposed backside region to the contact region;
a dielectric material formed overlying an upper surface region of a resulting structure overlying the bulk substrate member, wherein the resulting structure includes at least the first and second electrode members; and
an acoustic reflector structure configured overlying the first electrode member, the upper portion, the lower portion, and the second electrode member.
2 . The device of claim 1 wherein the support member is configured in a plane coincident with a bottom surface region of the bulk substrate member.
3 . The device of claim 1 wherein the support member is configured in a plane off-set and recessed in reference to a bottom surface region of the bulk substrate member.
4 . The device of claim 1 wherein the single crystal piezo material is characterized by X-ray diffraction with clear peak at a detector angle (2-Theta) associated with single crystal film and whose Full Width Half Maximum (FWHM) is measured to be less than 1.0°.
5 . The device of claim 1 wherein the single crystal piezo material is selected from at least one of AlN, AlGaN, InN, BN, or other group III nitrides; and wherein the single crystal piezo material has a thickness of greater than 0.4 microns, the single crystal piezo material being characterized by a dislocation density of less than 10 12 defects/cm 2 .
6 . The device of claim 1 further comprising
a first electrode terminal electrically coupled to the first electrode member; and
a second electrode terminal electrically coupled to the second electrode member.
7 . The device of claim 1 wherein the first and second electrode members comprise a tantalum or molybdenum material; and wherein the substrate comprises silicon, gallium arsenide, gallium nitride, aluminum nitride, or aluminum oxide material.
8 . An acoustic film device comprising:
a bulk substrate member having a bulk surface region, a thickness of material, and a highly-ordered crystal orientation;
a first thickness of single crystal piezo material formed overlying the bulk surface region, the first thickness of single crystal piezo material having a surface region, and having backside region which nucleates on the bulk surface region;
a second thickness of single crystal piezo material formed overlying the surface region of the first thickness of single crystal piezo material, the second thickness of single crystal piezo material having a surface region, and having a strain state and piezoelectric constant; and
a third thickness of single crystal piezo material formed overlying the surface region of the second thickness of single crystal piezo material, and having a strain state and high piezoelectric constant;
wherein the first, second, and third single crystal piezo materials being characterized by a dislocation density of less than 10 12 defects/cm 2 .
9 . The device of claim 8 wherein the bulk substrate comprises a silicon, gallium arsenide, gallium nitride, aluminum nitride, silicon carbide, silicon-on-insulator (SOI), or aluminum oxide material.
10 . The device of claim 8 wherein the first single crystal piezo material comprises an aluminum nitride, silicon nitride, or gallium nitride material; and wherein the single crystal piezo material has a thickness of greater than 0.1 microns.
11 . The device of claim 8 wherein the second single crystal piezo material comprises an aluminum nitride, scandium aluminum nitride, silicon nitride, or gallium nitride material; and wherein the single crystal piezo material has a thickness of greater than 0.1 microns.
12 . The device of claim 8 wherein the third single crystal piezo material comprises a scandium aluminum nitride (Sc x Al (1-X) N), where the scandium mole fraction (x) is less than 50%; and wherein the single crystal piezo material has a thickness of greater than 0.2 microns.
13 . The device of claim 8 wherein the single crystal piezo materials are characterized by X-ray diffraction with clear peak at a detector angle (2-Theta) associated with single crystal film and whose Full Width Half Maximum (FWHM) is measured to be less than 1.0°.
14 . The device of claim 8 wherein the third single crystal piezo material comprises a mechanical coupling (k t 2 ) of greater than 7%.