CN105992115B - Electrical wiring structure and electrical wiring method of silicon condenser microphone - Google Patents
Electrical wiring structure and electrical wiring method of silicon condenser microphone Download PDFInfo
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- CN105992115B CN105992115B CN201510092043.1A CN201510092043A CN105992115B CN 105992115 B CN105992115 B CN 105992115B CN 201510092043 A CN201510092043 A CN 201510092043A CN 105992115 B CN105992115 B CN 105992115B
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Abstract
The invention provides an electric connection structure of a silicon condenser microphone and an electric connection method thereof. The electrical connection method includes: s1: generating one or more groups of sacrificial layers and conducting layers which are staggered on a substrate, and forming a plurality of step structures among the sacrificial layers, the conducting layers or the substrate; s2: and growing a metal layer, reserving the metal electrodes attached to the step structures in the metal layer, and removing other parts of the metal layer. The invention can realize the functions of electrical connection, wiring intersection and electrical shielding among different conducting layers according to the setting requirement of the silicon microphone, thereby improving the indexes of sensitivity, linearity, signal to noise ratio and the like.
Description
Technical Field
The invention relates to the technical field of silicon microphones, in particular to a sensitive structure for a silicon condenser microphone and an electrical wiring method thereof.
Background
Micro-electro-mechanical system (MEMS) microphones or silicon condenser microphones are widely used for sound collection of flat electronic devices due to their advantages of small size and surface mounting, for example: cell phone, MP3, recording pen and monitor equipment. In the related art, a silicon condenser microphone includes a sensitive structure (also called a transducer), a supporting integrated circuit, and a package component, where the sensitive structure includes a substrate, a back plate, and a diaphragm. The electrical signals of the back plate, the diaphragm and other parts of the sensitive structure are electrically led out to a matched integrated circuit or other packaging parts, and the method is an essential link in the process of transmitting the electrical signals after the sound signals are converted into the electrical signals.
In the process of electric signal transmission, the realization of functions such as electric connection, wiring intersection, electric shielding and the like corresponds to electric connection and interference with different complexity degrees and is related to the quality of electric signal transmission. In a high-performance silicon condenser microphone product, the electric wiring of the sensitive structure directly affects the overall sensitivity, linearity, signal-to-noise ratio and other indexes of the silicon condenser microphone.
The lift-off process is a method of creating a structure of a target material on a substrate surface by a sacrificial material. In a traditional silicon condenser microphone, a lift-off process is generally used for manufacturing bonding pads (contact points) at different flat positions of a conducting layer for electric leads, electric signals are led out, or a large-area metal layer is manufactured at the flat position of the conducting layer to improve local conductivity and optimize an electric shielding effect, so that the manufacturing and stripping processes of the metal layer are the most intuitive and least difficult to realize. However, as the performance of silicon condenser microphones improves, more complex electrical traces on the sensitive structures are also gaining increasing attention. Chinese patents CN101427593A and CN103552980A use multiple electrical contact leads and a shielding metal layer disposed on the conductive layer to improve the sensitive structure electrical routing, respectively. The scheme avoids the difficulty of arranging the metal layer on the step structure of the conducting layer to realize electrical connection, but the flexibility of electrical wiring is limited, so that the optimization of indexes such as sensitivity, linearity, signal-to-noise ratio and the like of the silicon capacitor microphone is limited.
Disclosure of Invention
The invention aims to overcome the defects of the existing silicon condenser microphone in the electric wiring technology, and provides an electric wiring structure for the silicon condenser microphone and a wiring method thereof, which can carry out more flexible electric wiring arrangement on a sensitive structure under the existing process level, thereby optimizing an electric signal transmission path and further improving the indexes of the silicon condenser microphone, such as sensitivity, linearity, signal to noise ratio and the like.
In order to achieve the purpose, the invention adopts the technical scheme that:
an electric connection line structure of a silicon condenser microphone comprises a substrate, a non-conductive layer and a conductive layer, wherein a plurality of step structures are formed among the substrate, the non-conductive layer and the conductive layer through a lift-off process, and a plurality of metal electrodes are attached to the step structures and used for forming electric connection among the conductive layers which are insulated from each other. Compared with the traditional silicon condenser microphone which generally uses lift-off technology to respectively manufacture the connecting line structure of the bonding pad (contact point) at the flat positions of different conducting layers or manufacture a large-area metal layer at the flat position of the conducting layer to improve the local conductivity and optimize the electric shielding effect, the invention arranges the metal electrode at the non-flat step structure to connect different conducting layers. If the requirement for realizing the process is higher, the connection mode can be set at will; if the process implementation is compatible with a general process to ensure that the production process and the cost are not changed, the corresponding metal layers for connecting different conductive layers are limited when being arranged.
Preferably, the electrical connection structure of the silicon condenser microphone, wherein the step structure height difference of the attached metal electrode is not more than 10 micrometers. When the step height is too high, the process risk of fracture due to too large drop exists in the growth process of the metal layer, so that the process difficulty is basically unchanged, and the step height needs to be limited.
Preferred electrical wiring junctions for silicon condenser microphones wherein the conductive layer material is doped monocrystalline silicon or doped polycrystalline silicon. In the preparation of the existing sensitive structure of the silicon condenser microphone, doped monocrystalline silicon and doped polycrystalline silicon are two materials which can form ohmic contact with a metal layer. The use of these two materials enables the electrical signal to be transmitted from the conductive layer to the metal layer with less loss and less interference.
Preferably, the electrical connection of the silicon condenser microphone, wherein the metal electrode attached to the step structure connects two conductive layers having different heights. The upper conducting layer and the lower conducting layer are connected, and the technical effect is equivalent to that blind holes are manufactured in a board-level circuit to connect the two different layers.
The preferred electrical connection of a silicon condenser microphone wherein the metal electrode attached to the stepped structure connects two conducting layers of the same height but geometrically disconnected. The same layer of conductor is connected, and the technical effect is equivalent to that flying wires are manufactured in a board-level circuit to connect two different areas.
Preferred electrical wiring junctions for silicon condenser microphones are those in which non-conductive layers interleaved between different conductive layers are filled with sacrificial layer material, a portion of which can be removed after the lift-off process is completed. Not only can avoid unnecessary avoidance be bypassed, but also the mode of removing the lower sacrificial layer at the later stage can be used for replacing the sacrificial layer with air insulation. When the dielectric constant of the sacrificial layer is larger than that of air, stray and parasitic capacitance of the wiring can be reduced.
The electrical connection structure of the silicon capacitor microphone is preferably characterized in that the sacrificial layer material filled between the different conductive layers has mobility between the conductive layers which are not attached by the metal electrode after removing the designated part, but has no relative movement between the two conductive layers connected by the metal electrode at the metal layer connection position. The removal of the sacrificial layer to make parts of the conductive layer movable is a standard process for the fabrication of sensitive structures for silicon condenser microphones. However, in the present invention, since there is a case where two conductive layers are connected by using a metal layer, in order to ensure that the process implementation is compatible with a general process to ensure that the production process and the cost are not changed, it is necessary to provide a limitation in setting the corresponding metal layers for connecting different conductive layers. So that there is no relative movement between the two conductive layers connected by the metal layer at the metal layer connection location. This avoids the risk of the metal layer acting as an electrical connection breaking fatigue due to the relative movement of the conductive layers, thereby causing an electrical disconnection.
In addition, the invention also provides an electrical wiring method of the silicon condenser microphone, which is characterized by comprising the following steps:
s1: one or more groups of sacrificial layers and conductive layers which are arranged in a staggered mode are arranged on the substrate, and parts of the sacrificial layers, the conductive layers or the substrate are exposed to the air by using a masking and etching method, so that a plurality of step structures are formed between the sacrificial layers, the conductive layers or the substrate;
s2: growing a metal layer to cover the whole structure obtained in step S1, and removing other parts of the metal layer by masking, etching and lift-off processes, wherein the metal electrodes attached to the step structures in the metal layer are remained.
The preferred method for electrically connecting silicon condenser microphones further comprises step S3: the unwanted sacrificial layer material is removed. Compared with the prior art, the invention has the beneficial effects that:
the invention carries out more flexible arrangement of the electric wiring structure on the sensitive structure, thereby optimizing the electric signal transmission path and further improving the indexes of the silicon condenser microphone, such as sensitivity, linearity, signal to noise ratio and the like. By using the technical scheme of the invention, the product performance can be improved on the basis of keeping the production efficiency, reliability, yield and cost of the product basically unchanged, the application occasions of the product are widened, and the product competitiveness is increased.
Drawings
FIG. 1 is a schematic diagram of a wiring scheme using lift-off technology in a conventional silicon condenser microphone;
FIG. 2 is a schematic diagram of one embodiment of a silicon condenser microphone electrical wiring structure of the present invention;
fig. 3 to 8 are schematic diagrams of implementation steps of electrical connection, wire crossing and electrical shielding of the same and different conductive layers according to a preferred embodiment of the electrical wiring method for the silicon condenser microphone.
Detailed Description
The invention provides an electric wiring structure for a silicon condenser microphone and a wiring method thereof, which can carry out more flexible electric wiring arrangement on a sensitive structure under the existing process level, thereby optimizing an electric signal transmission path and further improving the indexes of sensitivity, linearity, signal to noise ratio and the like of the silicon condenser microphone. The invention is further illustrated by the following specific figures and examples.
Fig. 1 is a schematic view of a structure of a conventional silicon condenser microphone using a lift-off process. It is most intuitive to fabricate pads (contact points) 41/42 at the flat portions of the different conductive layers 31/32 for electrical leads to lead out electrical signals, or fabricate a large-area metal layer (not shown) at the flat portion of the conductive layer 31/32 to improve local conductivity for optimizing electrical shielding. The scheme avoids the difficulty of arranging the metal layer on the step structure of the conducting layer to realize electrical connection, but the flexibility of electrical wiring is limited, so that the optimization of indexes such as sensitivity, linearity, signal-to-noise ratio and the like of the silicon capacitor microphone is limited.
Fig. 2 is a schematic diagram of an embodiment of an electrical wiring structure of a silicon condenser microphone of the present invention. As shown in fig. 2, this embodiment of the present invention includes a substrate 101 'and non-conductive layers (sacrificial layers) 201' and 202 ', and conductive layers 301' and 302 ', alternately disposed on the substrate 101'. By a mask and an etching method, the conductive layers 301 ' and 302 ' and the conductive layer 301 ' and the substrate 101 ' are formed with a step structure, and the metal electrode 401 ' is attached to the step structure formed by the conductive layers 301 ' and 302 ' insulated from each other, thereby achieving electrical connection between the conductive layers 301 ' and 302 '. That is, the present invention requires that a metal electrode be provided at the non-flat step and that different conductive layers be connected. If the requirement for realizing the process is higher, the connection mode can be set at will; if the process implementation is compatible with a general process to ensure that the production process and the cost are not changed, the corresponding metal electrodes connected with different conductive layers are limited when being arranged.
Fig. 3-8 are schematic diagrams of the steps of the implementation scheme of the electrical connection, the wire crossing and the electrical shielding of the same and different conductive layers according to the preferred embodiment of the invention. The specific implementation steps of the preferred embodiment are as follows:
a) as shown in fig. 3, a sacrificial layer 201 is first grown on a substrate 101 of doped monocrystalline silicon material, a conductive layer 301 of doped polycrystalline silicon material is then grown, and the conductive layer 301 is masked and etched using a mask so that a portion of the sacrificial layer 201 is exposed.
b) As shown in fig. 4, based on the operation of fig. 3, a sacrificial layer 202 is grown again, and the conductive layer 301 and the sacrificial layer 201 are all masked.
c) As shown in fig. 5, based on the operation of fig. 4, a conductive layer 302 of doped polysilicon material is grown, and the conductive layer 302 is masked and etched using a mask, so that a portion of the sacrificial layer 202 is exposed.
d) As shown in fig. 6, on the basis of the operation of fig. 5, a reticle masks and etches sacrificial layers 201 and 202, leaving portions of conductive layer 201 and substrate 101 exposed.
e) As shown in fig. 7, on the basis of the operation of fig. 6, a metal layer is grown and masked and etched by using a mask, and an unnecessary metal layer is stripped off by a lift-off process, leaving a metal electrode 401.
f) As shown in fig. 8, upon operation of fig. 7, the unwanted sacrificial layer 201 and 202 material is removed, but no relative motion is allowed between the two conductive layers connected by the metal layer at the metal layer connection location. Thus, a metal layer 4011 connecting the conductive polysilicon layers 201 and 202, a metal layer 4011 connecting the conductive polysilicon layer 201 and the conductive substrate layer 101, a metal layer 4014 connecting the conductive polysilicon layer 202 and the conductive substrate layer 101, and a metal layer 4013 connecting the two portions of the conductive polysilicon layer 202 which are originally geometrically disconnected and insulated from each other can be obtained. The metal layer structures can be further utilized to realize the functions of electrical connection, wiring intersection and electrical shielding among different conductive layers, so that the indexes of sensitivity, linearity, signal-to-noise ratio and the like of the silicon condenser microphone are improved.
In the above preferred embodiment, some steps required to be added or deleted or modified for the arrangement of the sensitive structure of the silicon condenser microphone are allowed, but the metal layer forms electrical connection between at least two conductive layers which are originally insulated from each other, and by such lift-off wiring method, more flexible electrical wiring arrangement can be realized on the sensitive structure through the existing process level, so that an electrical signal transmission path is optimized, and the indexes of the sensitivity, the linearity, the signal-to-noise ratio and the like of the silicon condenser microphone are further improved.
The foregoing description of the invention is illustrative and not restrictive, and it will be understood by those skilled in the art that many changes, variations or equivalents may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (9)
1. An electric connection line structure of a silicon condenser microphone comprises a substrate, a non-conductive layer and a conductive layer, wherein a plurality of step structures are formed among the substrate, the non-conductive layer and the conductive layer through a lift-off process, and the electric connection line structure is characterized in that a plurality of metal electrodes are attached to the step structures and used for forming electric connection between the conductive layers which are insulated from each other, wherein the metal electrodes attached to the step structures are used for connecting two conductive layers with different heights or two conductive layers with the same height and geometric disconnection.
2. The electrical wiring structure of a silicon condenser microphone of claim 1, wherein the step structure height difference of the attached metal electrode does not exceed 10 microns.
3. The silicon condenser microphone electrical wiring structure of claim 1, wherein the conductive layer material is doped monocrystalline silicon or doped polycrystalline silicon.
4. The electrical wiring structure of a silicon condenser microphone of claim 1, wherein the non-conductive layers interleaved between different conductive layers are filled with a sacrificial layer material, and a portion of the sacrificial layer material is removed after a lift-off process is completed.
5. The electrical wiring structure of the silicon condenser microphone of claim 4, wherein the conductive layers to which the metal electrodes are not attached have mobility therebetween, but there is no relative movement between the two conductive layers to which the metal electrodes are attached at the connection with the metal electrodes.
6. An electrical wiring method for a silicon condenser microphone, comprising the steps of:
s1: one or more groups of sacrificial layers and conductive layers which are arranged in a staggered mode are arranged on the substrate, and parts of the sacrificial layers, the conductive layers or the substrate are exposed to the air by using a masking and etching method, so that a plurality of step structures are formed between the sacrificial layers, the conductive layers or the substrate;
s2: growing a metal layer to cover the whole structure obtained in step S1, and removing other parts of the metal layer by masking, etching and lift-off processes, wherein the metal electrodes attached to the step structures in the metal layer are remained.
7. The silicon condenser microphone electrical wiring method of claim 6, further comprising the step S3 of: the unwanted sacrificial layer material is removed.
8. The silicon condenser microphone electrical wiring method of claim 6, wherein the step structure height difference of the attached metal electrodes does not exceed 10 micrometers.
9. The silicon condenser microphone electrical wiring method of claim 6, wherein the conductive layer material is doped monocrystalline silicon or doped polycrystalline silicon.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101588529A (en) * | 2009-06-30 | 2009-11-25 | 瑞声声学科技(深圳)有限公司 | Silica-based condenser microphone and production method thereof |
| CN102241388A (en) * | 2011-05-18 | 2011-11-16 | 中国科学院上海微系统与信息技术研究所 | MEMS (micro electro mechanical system) wafer-level three-dimensional mixing integration packaging structure and method |
| CN102522136A (en) * | 2011-12-23 | 2012-06-27 | 南京航空航天大学 | Epitaxial silicon-based PIN node micro isotope battery and preparation method thereof |
| CN103456628A (en) * | 2012-05-29 | 2013-12-18 | 上海华虹Nec电子有限公司 | Manufacturing method of germanium-silicon heterojunction bipolar triode device |
| CN204598314U (en) * | 2015-02-28 | 2015-08-26 | 北京卓锐微技术有限公司 | A kind of electrical connecting wires structure of silicon capacitor microphone |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US9236815B2 (en) * | 2012-12-10 | 2016-01-12 | LuxVue Technology Corporation | Compliant micro device transfer head array with metal electrodes |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101588529A (en) * | 2009-06-30 | 2009-11-25 | 瑞声声学科技(深圳)有限公司 | Silica-based condenser microphone and production method thereof |
| CN102241388A (en) * | 2011-05-18 | 2011-11-16 | 中国科学院上海微系统与信息技术研究所 | MEMS (micro electro mechanical system) wafer-level three-dimensional mixing integration packaging structure and method |
| CN102522136A (en) * | 2011-12-23 | 2012-06-27 | 南京航空航天大学 | Epitaxial silicon-based PIN node micro isotope battery and preparation method thereof |
| CN103456628A (en) * | 2012-05-29 | 2013-12-18 | 上海华虹Nec电子有限公司 | Manufacturing method of germanium-silicon heterojunction bipolar triode device |
| CN204598314U (en) * | 2015-02-28 | 2015-08-26 | 北京卓锐微技术有限公司 | A kind of electrical connecting wires structure of silicon capacitor microphone |
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