CN217883833U

CN217883833U - Sensor, microphone and electronic equipment

Info

Publication number: CN217883833U
Application number: CN202221958933.8U
Authority: CN
Inventors: 胡振家
Original assignee: Weifang Goertek Microelectronics Co Ltd
Current assignee: Weifang Goertek Microelectronics Co Ltd
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2022-11-22
Anticipated expiration: 2032-07-27

Abstract

The utility model provides a sensor, microphone and electronic equipment, sensor include the substrate and set up the isolation layer on the substrate, and one side that the isolation layer deviates from the substrate is provided with vibrating diaphragm and back of the body utmost point, is formed with the clearance between vibrating diaphragm and the back of the body utmost point, is provided with the conducting layer in the back of the body utmost point, and the conducting layer is the IGZO layer. The sensor adopts IGZO as a conducting layer to replace the traditional heavily doped P-type polycrystalline silicon, the IGZO has smaller resistivity and higher forbidden bandwidth, the smaller resistivity can effectively reduce the thermal noise of the sensor, the higher forbidden bandwidth can increase the energy required by electronic transition, so that the photoexcited transition can not occur under the irradiation of visible light, and the optical noise is effectively reduced. The sensor has the advantage of being capable of reducing optical noise and thermal noise.

Description

Sensor, microphone and electronic equipment

Technical Field

The utility model relates to a sensor field especially relates to a sensor, microphone and electronic equipment.

Background

To simulate a customer application scenario, 850nm light is typically used to verify optical noise because Eg = hc/λ =1024/λ, and for 850nm wavelength light, semiconductor valence band electrons with Eg less than 1.46ev will be excited to the conduction band as free electrons that can conduct, but semiconductors with Eg greater than 1.46ev will not be excited by light with wavelength greater than 850 nm. The back electrode conducting layer of the existing microphone is heavily doped P-type polysilicon, the forbidden bandwidth of the polysilicon is only 1.1ev, and light with the wavelength less than 1127nm can excite holes in the valence band to the conduction band, so that the holes become free carriers. This photoelectric effect can increase MEMS noise, thereby affecting the normal use of MEMS MICs.

In view of the above, there is a need for a new sensor, microphone and electronic device to solve or at least alleviate the above technical drawbacks.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a sensor, microphone and electronic equipment aims at solving the big technical problem of sensor noise among the prior art.

In order to achieve the above object, according to an aspect of the present invention, the utility model provides a sensor, including the basic unit, the basic unit include the substrate with set up in isolation layer on the substrate, the isolation layer deviates from one side of substrate is provided with vibrating diaphragm and back of the body utmost point, the vibrating diaphragm with be formed with the clearance between the back of the body utmost point, be provided with the conducting layer in the back of the body utmost point, the conducting layer is the IGZO layer.

In one embodiment, a protruding end protruding toward the diaphragm is formed on a side of the back electrode facing the diaphragm.

In an embodiment, the sensor further includes a sound inlet, and a diaphragm structure is disposed on a side of the diaphragm facing the sound inlet.

In one embodiment, the diaphragm is a polyimide film.

In an embodiment, a conductive adhesion layer adhered to the diaphragm is further disposed on a side of the diaphragm facing the back electrode.

In an embodiment, the conductive adhesive layer is a graphene oxide layer or a metal layer.

In one embodiment, the diaphragm is provided with a gas release hole, and the position of the conductive adhesive layer corresponding to the gas release hole is provided with a through hole communicated with the gas release hole.

In one embodiment, the sensor further forms a sound outlet, and the sound outlet is disposed through the back electrode and the conductive layer.

In an embodiment, the sensor further includes a conductive connection layer, a first pin and a second pin, the first pin is electrically connected to the conductive layer, and the conductive connection layer connects the diaphragm and the second pin.

According to the utility model discloses a further aspect, the utility model discloses still provide a microphone, microphone includes the casing, still includes the aforesaid the sensor, the sensor set up in the casing.

According to another aspect of the present invention, the present invention also provides an electronic device, which includes the microphone described above.

In the above scheme, the sensor includes the basic unit, and the basic unit includes the substrate and sets up the isolation layer on the substrate, and one side that the isolation layer deviates from the substrate is provided with vibrating diaphragm and back of the body utmost point, is formed with the clearance between vibrating diaphragm and the back of the body utmost point, is provided with the conducting layer in the back of the body utmost point, and the conducting layer is the IGZO layer. The utility model discloses an adopting IGZO to replace traditional heavily doped P type polycrystalline silicon, IGZO has less resistivity and higher forbidden bandwidth, and less resistivity can effectively reduce the thermal noise of sensor, and higher forbidden bandwidth can increase the required energy of electron transition for visible light does not take place the photoexcitation transition, effectively reduces light and irritates. The utility model discloses a have and can reduce the merit of the light is manic and thermal noise. Moreover, the IGZO film can be obtained through low-temperature sputtering deposition, has good film consistency, is suitable for large-area production, can form good ohmic contact with metal Ti, has high process fusion degree with silicon, and is a practical and effective optical noise improvement scheme.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the description below are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a sensor according to an embodiment of the present invention;

fig. 2 is another schematic structural diagram of a sensor according to an embodiment of the present invention;

fig. 3 is a schematic structural view of the vibrating diaphragm and the conductive adhesive layer according to the embodiment of the present invention.

The reference numbers illustrate:

1. a base layer; 2. an isolation layer; 3. vibrating diaphragm; 31. a textured film structure; 32. an air release hole; 4. a back electrode; 41. an overhang; 5. a conductive layer; 6. a gap; 7. a conductive adhesive layer; 71. a through hole; 8. a conductive connection layer; 9. a first pin; 10. a second pin; 11. a sound outlet; 12. and a sound inlet.

The purpose of the present invention, its functional features and advantages will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

It should be noted that all the directional indicators (such as upper and lower 8230; etc.) in the embodiments of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, descriptions in the present application as to "first", "second", and the like are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit to the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

Moreover, the technical solutions of the embodiments of the present invention can be combined with each other, but it is necessary to use a person skilled in the art to realize the basis, and when the technical solutions are combined and contradictory or impossible to realize, the combination of the technical solutions should not exist, and the combination is not within the protection scope of the present invention.

Referring to fig. 1, according to an aspect of the present invention, the present invention provides a sensor, including basic unit 1, basic unit 1 includes the substrate and sets up isolation layer 2 on the substrate, and one side that isolation layer 2 deviates from the substrate is provided with vibrating diaphragm 3 and back of the body utmost point 4, is formed with clearance 6 between vibrating diaphragm 3 and the back of the body utmost point 4, is provided with conducting layer 5 in the back of the body utmost point 4, and conducting layer 5 is the IGZO layer.

Specifically, the substrate may be made of metal silicon, and the isolation layer 2 may be an oxide layer, which may play a role of support and insulation, and may also form a vibration structure together with the diaphragm 3. The back electrode 4 is typically made of silicon nitride and can serve as a support and an insulator. In the embodiment, IGZO (indium gallium zinc oxide, chinese name: indium gallium zinc oxide) is adopted to replace the traditional heavily doped P-type polycrystalline silicon, the IGZO has smaller resistivity and higher forbidden bandwidth, the smaller resistivity can effectively reduce the thermal noise of the sensor, the higher forbidden bandwidth can increase the energy required by electronic transition, so that the photoexcited transition can not occur under the irradiation of visible light, and the optical noise can be effectively reduced. This embodiment has the advantage that optical noise and thermal noise can be reduced. Moreover, the IGZO film can be obtained through low-temperature sputtering deposition, has good film consistency, is suitable for large-area production, can form good ohmic contact with metal Ti, has high process fusion degree with silicon, and is a practical and effective optical noise improvement scheme.

It should be noted that IGZO is a known material, and the present invention is applied to a sensor by making a conductive layer 5 structure from the known material IGZO, rather than inventing a novel material, which is a protection object of the present invention.

In a specific embodiment, the resistivity of the IGZO layer is 0.1 Ω · m, and the forbidden bandwidth of the IGZO layer is greater than 3eV. The resistivity of the traditional polycrystalline silicon is 50-80 omega-m, and the resistivity of the conducting layer 5 can be greatly reduced by adopting an IGZO layer with the resistivity of 0.1 omega-m, so that the thermal noise of the sensor is further reduced; the semiconductor valence band electron that general Eg is less than 1.46eV can be aroused the conduction band, the utility model discloses a forbidden bandwidth is greater than 3 eV's IGZO layer, can avoid photoelectron to take place the transition, and the light that further reduces the sensor is happy.

Referring to fig. 1 or 2, in one embodiment, the side of the back electrode 4 facing the diaphragm 3 is formed with a protruding end 41 protruding toward the diaphragm 3. The protruding end 41 is provided to prevent the diaphragm 3 from adhering to the back electrode 4, and to provide a support for the diaphragm 3 to prevent the diaphragm 3 from being deformed too much. Specifically, the size of the protruding end 41 may gradually decrease from the back electrode 4 toward the side of the diaphragm 3.

Referring to fig. 1 or 2, in an embodiment, the sensor further includes a sound inlet 12, and a diaphragm structure 31 is disposed on a side of the diaphragm 3 facing the sound inlet 12. Specifically, the diaphragm structure 31 may be a convex structure provided toward the sound inlet 12 to improve the compliance, sensitivity, and elastic properties of the diaphragm 3.

In one embodiment, the diaphragm 3 is a polyimide film. Polyimide (abbreviated as PI) is a polymer having an imide ring (-CO-N-CO-) in the main chain, and is one of organic polymer materials having the best overall performance. This embodiment adopts polyimide preparation vibrating diaphragm 3, specifically, can adopt nanometer polyimide preparation vibrating diaphragm 3, compares and adopts polycrystalline silicon preparation vibrating diaphragm 3 among the prior art, and on the one hand, the polyimide layer has good mechanical properties, makes vibrating diaphragm 3 be difficult for breaking, and on the other hand adopts nanometer polyimide, can realize ultra-thin structure. In the prior art, in the manufacture of a large-size sensor, the size of the diaphragm 3 is increased, and the thickness of the diaphragm 3 needs to be increased in order to ensure the mechanical performance of the diaphragm 3, but in this embodiment, the diaphragm 3 is manufactured by using nano-grade polyimide, so that the mechanical reliability of the diaphragm 3 can be ensured without increasing the thickness of the diaphragm 3, and an ultrathin structure of the large-size sensor is realized. And, adopt polyimide preparation vibrating diaphragm 3 simple process, directly get rid of the glue after the etching substrate 1 and coat polyimide on the substrate, the air escape hole 32 on the vibrating diaphragm 3 accessible oxygen ion is direct to be punctured, and the line membrane structure 31 on the vibrating diaphragm 3 also can be made through ion etching.

Referring to fig. 2 and 3, in an embodiment, a side of the diaphragm 3 facing the back electrode 4 is further provided with a conductive adhesion layer 7 adhered to the diaphragm 3. The conductive adhesive layer 7 is a graphene oxide layer or a metal layer. The graphene is sp ² The hybridized and connected carbon atoms are tightly packed into a new material with a single-layer two-dimensional honeycomb lattice structure. Graphene is one of the materials with the highest known strength, and meanwhile, the graphene also has good toughness, can be bent, and has excellent conductivity. Through sputtering deposit one deck graphite alkene layer as electrically conductive laminating layer 7 at polyimide face back of the body 4's surface, combine nanometer polyimide and oxidation graphite alkene mutually, compare in prior art and only adopt silicon nitride preparation vibrating diaphragm 3, have following advantage at least: 1. the coating has the performances of corrosion resistance, high temperature resistance, organic solvent resistance and illumination resistance; 2. the insulating property and the dielectric property are good; 3. has better planarization performance than silicon nitride; 4. the adhesive has good adhesion performance to Si, al, ceramics, dielectric materials and the like; 5. the storage is convenient, the process is simple, and the method is suitable for large-scale production of chips; 6. the graphene oxide sputtered on the surface of the polyimide film is used as a shielding electrode, the thickness of the shielding electrode is greatly reduced, and due to the characteristics of electric conductivity and a single-layer structure of the graphene, the charging and discharging speed of the MEMS can be increased, the bending deformation capacity of the vibrating diaphragm 3 can be additionally enhanced, the mechanical reliability is enhanced, and the sensitivity of the MEMS is improved; 7. the nano polyimide and the graphene oxide are combined to realize the diaphragm 3 structure with an ultrathin size, and the diaphragm is particularly suitable for manufacturing the ultrathin structure of a large-size microphone.

Of course, the conductive adhesion layer 7 may also be made of metal, and the metal layer may be an aluminum layer or a gold layer or made of other metal materials. Here, the conductive adhesive layer 7 may have good mechanical properties by using a metal layer, but the effect of realizing an ultra-thin size is not as good as that of using graphene because the conductive adhesive layer 7 is made of a metal layer with a larger thickness than graphene. Of course, the metal layer may also be formed on the surface of the diaphragm 3 by a sputtering deposition method.

Referring to fig. 2 and 3, in an embodiment, the diaphragm 3 is provided with a relief hole 32, and the conductive adhesive layer 7 is provided with a through hole 71 communicating with the relief hole 32 at a position corresponding to the relief hole 32. Because set up electrically conductive laminating 7 on vibrating diaphragm 3 to electrically conductive laminating 7 is located clearance 6, for avoiding electrically conductive laminating 7 to block up disappointing hole 32, consequently, electrically conductive laminating 7 should set up through-hole 71 in the position that corresponds disappointing hole 32, through-hole 71 and disappointing hole 32 intercommunication, in order to ensure clearance 6 through disappointing hole 32 and through-hole 71 and external intercommunication, reach atmospheric pressure balance.

Referring to fig. 1 and 2, in an embodiment, the sensor further includes a conductive connection layer 8, a first lead 9 and a second lead 10, the first lead 9 is electrically connected to the conductive layer 5, and the conductive connection layer 8 connects the diaphragm 3 and the second lead 10. The vibrating diaphragm 3 and the back electrode 4 form two polar plates of a capacitor, sound enters from the sound inlet 12 and is transmitted to the vibrating diaphragm 3 to cause the vibrating diaphragm 3 to vibrate, the distance between the vibrating diaphragm 3 and the back electrode 4 changes, and the change is converted into an electric signal which is transmitted to the first pin 9 and the second pin 10 through the conducting layer 5 and the conducting connecting layer 8 respectively. In particular, the conductive layer 5 is arranged in the back electrode 4, a channel may be arranged in the back electrode 4 for receiving the conductive layer 5, and the first pin 9 and the second pin 10 may be metal pads.

According to the utility model discloses an on the other hand, the utility model discloses still provide a microphone, microphone includes the casing, still includes foretell sensor, and the sensor sets up in the casing. Since the microphone includes all technical solutions of all embodiments of all the sensors, at least all beneficial effects brought by all the technical solutions are achieved, and no further description is given here.

According to another aspect of the present invention, the present invention also provides an electronic device, which includes the above-mentioned microphone. Since the electronic device includes all technical solutions of all embodiments of all the microphones, at least all beneficial effects brought by all the technical solutions are achieved, and no further description is given here.

Above only be the utility model discloses an optional embodiment to do not consequently restrict the utility model discloses a patent range, all be in the utility model discloses a technical idea down, utilize the equivalent structure transform of doing of the contents of description and the attached drawing, or direct/indirect application all is included in other relevant technical field the utility model discloses a patent protection scope.

Claims

1. The sensor is characterized by comprising a base layer, wherein the base layer comprises a substrate and an isolation layer arranged on the substrate, one side of the isolation layer, which deviates from the substrate, is provided with a vibrating diaphragm and a back electrode, a gap is formed between the vibrating diaphragm and the back electrode, a conducting layer is arranged in the back electrode, and the conducting layer is an IGZO layer.

2. A transducer according to claim 1, wherein the side of the back electrode facing the diaphragm is formed with a protruding end projecting towards the diaphragm.

3. The sensor of claim 1, further comprising a sound inlet, wherein a diaphragm structure is disposed on a side of the diaphragm facing the sound inlet.

4. A sensor according to any one of claims 1 to 3, wherein the diaphragm is a polyimide film.

5. A sensor according to any one of claims 1 to 3, wherein a conductive adhesive layer is further provided on a side of the diaphragm facing the back electrode, the conductive adhesive layer being adhered to the diaphragm.

6. The sensor of claim 5, wherein the conductive adhesive layer is a graphene oxide layer or a metal layer.

7. The sensor according to claim 5, wherein the diaphragm is provided with a gas release hole, and a through hole communicated with the gas release hole is formed in a position of the conductive adhesive layer corresponding to the gas release hole.

8. The sensor of any one of claims 1-3, further comprising a conductive connection layer, a first pin and a second pin, the first pin being electrically connected to the conductive layer, the conductive connection layer connecting the diaphragm and the second pin.

9. A microphone, characterized in that the microphone comprises a housing and further comprises a sensor according to any of claims 1-8, which sensor is arranged in the housing.

10. An electronic device, characterized in that the electronic device comprises a microphone according to claim 9.