Acoustic transduction structure and manufacturing method thereof and acoustic transducer

An acoustic transduction structure, comprising:

• a base substrate and at least two acoustic transduction units on the base substrate, wherein,
• the at least two acoustic transduction units comprise:
• a central acoustic transduction unit and at least one annular acoustic transduction unit around and spaced apart from the central acoustic transduction unit;
• wherein the at least one annular acoustic transduction unit comprises a plurality of annular acoustic transduction units;
• and
• the plurality of annular acoustic transduction units are provided on the base substrate around the central acoustic transduction unit and are sequentially provided along a direction away from the central acoustic transduction unit;
• wherein each of the at least two acoustic transduction units comprises:
• a first electrode on the base substrate;
• a support pattern on a side of the first electrode distal to the base substrate, wherein the support pattern surrounds to form a vibrating cavity of the acoustic transduction unit;
• a vibrating diaphragm pattern on a side of the support pattern distal to the first electrode, and configured to vibrate in the vibrating cavity;
• and
• a second electrode on a side of the vibrating diaphragm pattern distal to the first electrode, and opposite to the first electrode,
• wherein shapes of orthographic projections of the first electrode, the second electrode and the vibrating cavity of the central acoustic transduction unit on the base substrate each are a circular shape, and/or shapes of orthographic projections of the first electrode, the second electrode and the vibrating cavity in each of the plurality of annular acoustic transduction units on the base substrate each are an annular shape;
• the orthographic projection of the first electrode of each of the plurality of annular acoustic transduction units on the base substrate surrounds the orthographic projection of the first electrode in the central acoustic transduction unit on the base substrate;
• the orthographic projection of the vibrating cavity of each of the plurality of annular acoustic transduction units on the base substrate surrounds the orthographic projection of the vibrating cavity of the central acoustic transduction unit on the base substrate;
• and
• the orthographic projection of the second electrode of each of the plurality of annular acoustic transduction units on the base substrate surrounds the orthographic projection of the second electrode of the central acoustic transduction unit on the base substrate;
• and
• wherein orthographic projections of the vibrating cavities of any two adjacent acoustic transduction units of the at least two acoustic transduction units on the base substrate are spaced apart from each other by a predetermined distance;
• and
• wherein the predetermined distance between the orthographic projections of the vibrating cavities of any two adjacent acoustic transduction units on the base substrate satisfies:
• 0.4λ≤d≤0.6λ, d is the predetermined distance, and λ is a wavelength of an acoustic wave emitted by the acoustic transduction structure.

A manufacturing method of an acoustic transduction structure, wherein the acoustic transduction structure comprises a base substrate and at least two acoustic transduction units on the base substrate, and the at least two acoustic transduction units comprise:

• a central acoustic transduction unit and at least one annular acoustic transduction unit around and spaced apart from the central acoustic transduction unit,
• the manufacturing method comprises steps of:
• forming at least two acoustic transduction units on a base substrate such that the at least two acoustic transduction units comprise:
• a central acoustic transduction unit and at least one annular acoustic transduction unit around and spaced apart from the central acoustic transduction unit;
• and
• the step of forming at least two acoustic transduction units on a base substrate comprises steps of:
• forming a first central electrode and at least one first annular electrode around and spaced apart from the first central electrode on the base substrate, wherein the first central electrode and the at least one first annular electrode are first electrodes of the central acoustic transduction unit and the at least one annular acoustic transduction unit, respectively, and the at least one first annular electrode is spaced apart from each other in a direction away from the first central electrode;
• forming a support pattern and a vibrating diaphragm pattern on a side of the first central electrode and the at least one first annular electrode distal to the base substrate, wherein the support pattern surrounds to form a central vibrating cavity and at least one annular vibrating cavity around the central vibrating cavity, and the central vibrating cavity and the at least one annular vibrating cavity are respectively vibrating cavities of the central acoustic transduction unit and the at least one annular acoustic transduction unit;
• and
• forming a second central electrode and at least one second annular electrode around the second central electrode on a side of the vibrating diaphragm pattern distal to the base substrate, wherein the second central electrode and the at least one second annular electrode are second electrodes of the central acoustic transduction unit and the at least one annular acoustic transduction unit, respectively.