Search

CN-115802256-B - Pixel sounding unit, manufacturing method thereof and digital sounding chip

CN115802256BCN 115802256 BCN115802256 BCN 115802256BCN-115802256-B

Abstract

The invention discloses a pixel sounding unit, a manufacturing method thereof and a digital sounding chip, which relate to the technical field of microelectronic manufacturing and are used for solving the problem of poor safety and reliability of the pixel sounding unit. The pixel sounding unit comprises an electrode structure layer, a vibrating diaphragm, a supporting structure and an electric isolation layer, wherein the supporting structure is arranged between the electrode structure layer and the vibrating diaphragm and comprises a plurality of supporting bodies which are distributed on the electrode structure layer at intervals, the electric isolation layer is arranged on the electrode structure layer and the supporting structure in a lamination mode and is used for electrically isolating the electrode structure layer from the vibrating diaphragm, the digital sounding chip comprises the pixel sounding unit provided by the technical scheme, and the manufacturing method of the pixel sounding unit comprises the pixel sounding unit provided by the technical scheme.

Inventors

  • LIU CHANGHUA
  • BI XUEDONG

Assignees

  • 地球山(苏州)微电子科技有限公司

Dates

Publication Date
20260512
Application Date
20221227

Claims (9)

  1. 1. The utility model provides a pixel sound generating unit, includes electrode structure layer and vibrating diaphragm, its characterized in that still includes: the support structure is arranged between the electrode structure layer and the vibrating diaphragm and comprises a plurality of support bodies which are distributed on the electrode structure layer at intervals; An electrical isolation layer, which is stacked on the electrode structure layer and the supporting structure, and is used for electrically isolating the electrode structure layer and the vibrating diaphragm; the electrode structure layer comprises a dividing ring groove, the dividing ring groove divides the electrode structure layer into an inner ring portion and an outer ring portion, the inner ring portion is electrically isolated from the outer ring portion, the supporting bodies are located on the inner ring portion, and the dividing ring groove is provided with a plurality of supporting bodies, and the number of the dividing ring groove is identical to that of the supporting bodies.
  2. 2. The pixel sounding unit of claim 1, wherein the split ring grooves are filled with an insulating structure.
  3. 3. The pixel sound generating unit according to claim 2, wherein the insulating structure is integral with the electrically isolating layer.
  4. 4. The pixel sounding unit according to claim 1, wherein the split ring groove has a circular ring structure, and a difference between an inner diameter and an outer diameter of the split ring groove is 0.5 μm to 2 μm.
  5. 5. The pixel sounding unit according to claim 4, wherein the support body has a cylindrical structure, and a portion of the electrically isolated layer laminated on the support body has a rounded chamfer; The diameter of the cross section of the support body is 1-5 mu m, and the difference between the inner diameter of the dividing ring groove and the outer diameter of the support body is 1-3 mu m.
  6. 6. The pixel sounding unit according to claim 1, wherein the material of the support is silicon dioxide or silicon nitride, and the height of the support is 150 nm-300 nm; And/or the material of the electric isolation layer is silicon nitride, and the thickness of the electric isolation layer is 150 nm-500 nm.
  7. 7. The pixel sounding unit of claim 1, wherein a plurality of the support bodies are arranged in an array.
  8. 8. A digital sound chip comprising the pixel sound generating unit according to any one of claims 1 to 7.
  9. 9. A method of manufacturing a pixel sound emitting unit according to any one of claims 1 to 7, comprising: providing an electrode structure layer; depositing a first dielectric layer on the electrode structure layer; Etching the first dielectric layer to form a support structure, wherein the support structure comprises a plurality of support bodies which are distributed on the electrode structure layer at intervals; etching the electrode structure layer to form a dividing ring groove, dividing the electrode structure layer into an electrically isolated ring inside and an electrically isolated ring outside by the dividing ring groove, and positioning the support body on the ring inside; And depositing a second dielectric layer on the electrode structure layer and the first dielectric layer, wherein the second dielectric layer is partially laminated on the electrode structure layer and the supporting structure to form an electric isolation layer, and the second dielectric layer is partially filled in the dividing ring groove to electrically isolate the inner part of the ring from the outer part of the ring.

Description

Pixel sounding unit, manufacturing method thereof and digital sounding chip Technical Field The invention relates to the technical field of microelectronic manufacturing, in particular to a pixel sounding unit, a manufacturing method thereof and a digital sounding chip. Background A speaker is a transducer device capable of converting an electrical signal into an acoustic signal. The speaker is the basis for making sound, acoustically active noise reduction devices, etc., and therefore, the performance of the speaker has a critical impact on the fabrication of acoustic devices. Compared with the traditional voice coil loudspeaker, the MEMS loudspeaker (MicroElectroMechanicalSystem), namely the micro-motor system loudspeaker, has the advantages of good consistency, low power consumption, small size, low price and the like. The MEMS loudspeaker commonly used at present consists of a plurality of pixel sounding units, wherein each pixel sounding unit comprises an electrode layer and a vibrating diaphragm, when the loudspeaker works, the vibrating diaphragm can vibrate up and down under the driving of electrostatic force of the electrode layer to realize sounding, but when the vibrating diaphragm moves downwards, the vibrating diaphragm is easy to contact with the electrode layer below, so that the safety and reliability of the pixel sounding units are affected. Disclosure of Invention The invention aims to provide a pixel sounding unit, a manufacturing method thereof and a digital sounding chip, so as to improve the safety and reliability of the pixel sounding unit. In order to achieve the above object, in a first aspect, the present invention provides a pixel sounding unit, including an electrode structure layer and a diaphragm, further including: The support structure is arranged between the electrode structure layer and the vibrating diaphragm and comprises a plurality of support bodies which are distributed on the electrode structure layer at intervals; and the electric isolation layer is arranged on the electrode structure layer and the supporting structure in a lamination manner and is used for electrically isolating the electrode structure layer from the vibrating diaphragm. Under the condition of adopting the technical scheme, the electrode structure layer and the diaphragm are electrically isolated through the electric isolation layer, the diaphragm is prevented from moving downwards to be in contact with the electrode structure layer, the safety of the pixel generating unit is improved, the supporting structure is arranged between the electrode structure layer and the diaphragm, the diaphragm can be supported through the supporting structure and the electric isolation layer when the diaphragm moves downwards, damage caused by overlarge amplitude after the diaphragm moves downwards is avoided, the reliability of the pixel generating unit is improved, when the diaphragm is an ultrathin diaphragm, the ultrathin diaphragm is easy to damage caused by overlarge amplitude when the diaphragm moves downwards, the ultrathin diaphragm is well supported through the supporting structure and the electric isolation layer, the damage caused by the downward movement of the ultrathin diaphragm can be avoided, the service life of the ultrathin diaphragm is prolonged, meanwhile, the distance between the diaphragm and the electrode structure layer can be increased through the supporting structure and the electric isolation layer, the actual electric field strength at the supporting structure is reduced, the possibility that the supporting structure is broken by the voltage between the diaphragm and the electrode structure is reduced, and the circuit safety and reliability of the pixel generating unit are improved. In some possible implementations, the electrode structure layer includes a split ring groove that splits the electrode structure layer into a ring interior and a ring exterior, the ring interior being electrically isolated from the ring exterior, the support being located on the ring interior. The arrangement is that the inside of the ring is electrically isolated from the outside of the ring, so that the actual electric field intensity at the supporting structure is further reduced, and the circuit safety and reliability of the pixel sounding unit are improved. In some possible implementations, the split ring grooves are filled with an insulating structure. The pixel sounding unit is characterized in that the ring is provided with a ring groove, the ring groove is filled with the insulation structure, the inside of the ring is further electrically isolated from the outside of the ring through the insulation structure, the circuit safety and the reliability of the pixel sounding unit are improved, and the overall stability of the pixel sounding unit is improved through the insulation structure filling the divided ring groove. In some possible implementations, the insulating structure is integral with the electr