Techniques are disclosed for forming a monolithic integrated circuit semiconductor structure that includes a radio frequency (RF) frontend portion and may further include a CMOS portion. The RF frontend portion includes componentry implemented with column III-N semiconductor materials such as gallium nitride (GaN), indium nitride (InN), aluminum nitride (AlN), and compounds thereof, and the CMOS portion includes CMOS logic componentry implemented with semiconductor materials selected from group IV of the periodic table, such as silicon, germanium, and/or silicon germanium (SiGe). Either of the CMOS or RF frontend portions can be native to the underlying substrate to some degree. The techniques can be used, for example, for system-on-chip integration of III-N transistors and/or RF filters, along with column IV CMOS devices on a single substrate. In a more general sense, the techniques can be used for SoC integration of an RF frontend having diverse III-N componentry on a single substrate, in accordance with some embodiments.

Chemical sensors include a functionalized electrode configured to change surface potential in the presence of an analyte. A piezoelectric element is connected to the functionalized electrode. A piezoresistive element is in contact with the piezoelectric element.

Methods of using and making chemical sensors include exposing a functionalized electrode to a substance to be tested. The functionalized electrode is electrically connected to a sensor having a piezoelectric element and a piezoresistive element. A voltage on the functionalized electrode controls a resistance of the piezoresistive element. A current is measured passing through the piezoresistive element. The presence of the analyte is determined based on the measured current.

A method of making an acoustic wave sensor includes the steps of providing a piezoelectric substrate layer and printing on the substrate layer a sensor layer comprising a first interdigitated acoustic wave transducer, a sensing film, and positioned on an opposing side of the sensing film from the first interdigitated acoustic wave transducer at least one selected from the group consisting of a second interdigitated acoustic wave transducer and a Bragg reflector. An insulation layer can be printed. An antenna can be printed in an antenna layer, and the insulation layer can be interposed between the antenna layer and the sensor layer. An electrical connection can be printed between the antenna and the first interdigitated acoustic wave transducer. An acoustic wave sensor is also disclosed.

A method, in accordance with one embodiment, includes forming an array of structures from a raw material via cold spray. Each of the structures is characterized by having a defined feature size in at least one dimension of less than 100 microns as measured in a plane of deposition of the structure, at least 90% of a theoretical density of the raw material, and essentially the same functional properties as the raw material. A method, in accordance with another embodiment, includes positioning a mask between a cold spray nozzle and a substrate, and forming a structure on the substrate by cold spraying a raw material from the cold spray nozzle. The structure has a shape corresponding to an aperture in the mask.

A method, in accordance with one embodiment, includes forming an array of structures from a raw material via cold spray. Each of the structures is characterized by having a defined feature size in at least one dimension of less than 100 microns as measured in a plane of deposition of the structure, at least 90% of a theoretical density of the raw material, and essentially the same functional properties as the raw material. A method, in accordance with another embodiment, includes positioning a mask between a cold spray nozzle and a substrate, and forming a structure on the substrate by cold spraying a raw material from the cold spray nozzle. The structure has a shape corresponding to an aperture in the mask.

A first organic resin layer is formed over a first substrate; a first insulating film is formed over the first organic resin layer; a first element layer is formed over the first insulating film; a second organic resin layer is formed over a second substrate; a second insulating film is formed over the second organic resin layer; a second element layer is formed over the second insulating film; the first substrate and the second substrate are bonded; a first separation step in which adhesion between the first organic resin layer and the first substrate is reduced; the first organic resin layer and a first flexible substrate are bonded with a first bonding layer; a second separation step in which adhesion between the second organic resin layer and the second substrate is reduced; and the second organic resin layer and a second flexible substrate are bonded with a second bonding layer.

Chemical sensors and methods of using and making the same include a functionalized electrode configured to change surface potential in the presence of an analyte. A piezoelectric element is connected to the functionalized electrode and is configured to change in volume in accordance with the surface potential of the functionalized electrode. A piezoresistive element is in contact with the piezoelectric element and is configured to change in resistance in accordance with the volume of the piezoelectric element.

A method for manufacturing a piezoelectric actuator is disclosed that includes forming a vibration plate, forming a plurality of electrodes on the vibration plate, forming a piezoelectric layer on the electrodes, and forming a common electrode on the piezoelectric layer.

Chemical sensors and methods of using and making the same include a functionalized electrode configured to change surface potential in the presence of an analyte. A piezoelectric element is connected to the functionalized electrode and is configured to change in volume in accordance with the surface potential of the functionalized electrode. A piezoresistive element is in contact with the piezoelectric element and is configured to change in resistance in accordance with the volume of the piezoelectric element.