Capacitive ultrasonic transducer device, manufacturing method thereof and transducer array
A capacitive ultrasonic transducer device includes a substrate, a first capacitive structure, a second capacitive structure, a first film structure and a second film structure. The first capacitive structure is disposed on the substrate, and includes a first electrode and a second electrode. A first gap and a dielectric layer are located between the first electrode and the second electrode. The second capacitive structure is disposed on the substrate, and includes a third electrode and a fourth electrode. A second gap is located between the third electrode and the fourth electrode. The first film structure is configured to seal the first gap. The second film structure is connected to the third electrode and the fourth electrode, and configured to seal the second gap. A first width between the first electrode and the second electrode is different from a second width of the second gap.
1. A capacitive ultrasonic transducer device, comprising:
a substrate;
a first capacitive structure disposed on the substrate, and comprising:
a first electrode; and
a second electrode, a first gap and a dielectric layer located between the first electrode and the second electrode;
a second capacitive structure disposed on the substrate, and comprising:
a third electrode; and
a fourth electrode, a second gap located between the third electrode and the fourth electrode;
a first film structure connected to the first electrode and the dielectric layer, and configured to seal the first gap; and
a second film structure connected to the third electrode and the fourth electrode, and configured to seal the second gap;
wherein a first width between the first electrode and the second electrode is different from a second width of the second gap.
2. The capacitive ultrasonic transducer device of claim 1 , wherein the first capacitive structure is a receiver, the second capacitive structure is a transmitter, and the first width is less than the second width.
3. The capacitive ultrasonic transducer device of claim 1 , wherein the first width is greater than or equal to 100 nanometer (nm), and less than or equal to 150 nm, and the second width is greater than or equal to 350 nm, and less than or equal to 450 nm.
4. The capacitive ultrasonic transducer device of claim 1 , wherein the first capacitive structure is a metal-inductor-metal (MIM) structure, and the second capacitive structure is a titanium nitride (TIN) capacitive structure.
5. The capacitive ultrasonic transducer device of claim 1 , wherein the capacitive ultrasonic transducer device is applied to one of a solid-state environment and a liquid environment.
6. The capacitive ultrasonic transducer device of claim 1 , wherein a thickness of the first film structure and a thickness of the second film structure are both greater than or equal to 0.5 micrometer (μm) and less than or equal to 5 μm.
7. The capacitive ultrasonic transducer device of claim 1 , further comprising:
two conductive structures electrically connected to the first capacitive structure and the second capacitive structure, respectively; and
two isolation layers covering the two conductive structures, respectively.
8. A transducer array, comprising:
a plurality of capacitive ultrasonic transducer devices, at least one of the capacitive ultrasonic transducer devices comprising:
a substrate;
a first capacitive structure disposed on the substrate, and comprising:
a first electrode; and
a second electrode, a first gap and a dielectric layer located between the first electrode and the second electrode;
a second capacitive structure disposed on the substrate, and comprising:
a third electrode; and
a fourth electrode, a second gap located between the third electrode and the fourth electrode;
a first film structure connected to the first electrode and the dielectric layer, and configured to seal the first gap; and
a second film structure connected to the third electrode and the fourth electrode, and configured to seal the second gap; and
an interface circuit for the capacitive ultrasonic transducer devices stacking thereon, and electrically connected to the capacitive ultrasonic transducer devices;
wherein a first width between the first electrode and the second electrode is different from a second width of the second gap.