CN102413407A - Middle-ear implantable miniature piezoelectric microphone and method for preparing same - Google Patents

Middle-ear implantable miniature piezoelectric microphone and method for preparing same Download PDF

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CN102413407A
CN102413407A CN2011103056611A CN201110305661A CN102413407A CN 102413407 A CN102413407 A CN 102413407A CN 2011103056611 A CN2011103056611 A CN 2011103056611A CN 201110305661 A CN201110305661 A CN 201110305661A CN 102413407 A CN102413407 A CN 102413407A
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microphone
middle ear
piezoelectric microphone
fixed
ossicular chain
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康厚墉
迟放鲁
胡国华
洪苏玲
肖青
沈暘
王小强
魏萍
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康厚墉
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Abstract

The invention belongs to the field of biomedical engineering bionics and relates to a middle-ear miniature microphone, in particular to a middle-ear implantable miniature piezoelectric microphone and a method for preparing the same. Main components of the middle-ear implantable miniature piezoelectric microphone provided by the invention comprise piezoelectric ceramic twin lamellae and a fixed piece, wherein strip-shaped piezoelectric ceramic twin lamellae of which the length is 1.5 to 4.0 mm, the width is 0.5 to 1.0 mm, the thickness is 0.2 to 0.3 mm and the mass is less than 7 mg are made of high-sensitivity and low-quality factor piezoelectric ceramics by a new process; the fixed piece is formed by combining a fixed clamping ring and a fixed sleeve ring and made of nickel titanium memory alloy; the fixed sleeve ring is formed by overlapping sheet-like alloy of which the width is 0.6 mm, the length is about 0.6 to 1.5 mm and the thickness is 0.1 mm; the fixed clamping ring is sleeved in the middle of the sheet-like sleeve ring; the fixed clamping ring consists of a pair of alloy wires with the diameter of 0.2 mm; and the overall mass of the fixed piece is about 4 mg. A printed amplification noise-reduction circuit system chip is integrated in a micro electromechanical system (MEMS), the length of the chip is less than 1.2 mm, the width of the chip is less than 0.8 mm, the thickness of the chip is less than 0.05 mm, the overall mass is about 1 to 2 mg, and a circuit system is etched and printed on a silicon substrate by using an MEMS process.

Description

A kind of middle ear implanted micro piezoelectric microphone and preparation method thereof
Technical field
The invention belongs to field of biomedical engineering bionics, relate to the middle ear midget microphone, be specifically related to a kind of middle ear implanted micro piezoelectric microphone and preparation method thereof.
Background technology
Hearing disabilities are the main disabled types of China and world other countries, and its main diseases is because sensorineural deafness.Because at present and in a very long time, still do not have such patient of active drug treatment, thereby implantable artificial cochlea, artificial middle ear or wear unique effective therapeutic modality that hearing aids becomes deaf, the middle severe induction of utmost point severe merve deafness patient.Present artificial cochlea is semi-implantation type, contains device outside such as microphone, battery, speech processor, transmitting coil.Device outside is brought the disability outward appearance, can not swim, returns when external damage, sleep inconveniences such as the noiseless world to the implant user.The development full-implanting type artificial cochlea can effectively solve these inconvenience, but does not make a breakthrough as yet.How external microphone being built in the body is one of main bottleneck.The implanted micro microphone can provide the core component support for the research and development of full implantable artificial cochlea.The artificial middle ear of implanted also are the current research focuses, and its key also is the development of implanted microphone.It can be implanted the auditory prosthesis that former necessitative aspect is worn in the middle ear outward, substitutes or the transaudient transformation function of enhancing middle ear (so claiming artificial middle ear).It is thus clear that the implanted microphone is full implantable artificial cochlea and the indispensable core component of artificial middle ear.The implanted microphone both can be assigned to stimulating electrode via stimulator so that the deaf patient of utmost point severe obtains the electric sense of hearing for the artificial cochlea provides electroacoustic signal with further processing then; It also can provide external acoustic signal for artificial middle ear system in real time; Again via amplifying and signal processing; Drive the auditory ossicular chain vibration then; Strengthen its Oscillation Amplitude (perilymph fluctuating range), make the transducing of external hair cell obtain gain, the severe deafness patient obtained the better sense of hearing during this gain can make.
The structure and the function of the deaf and middle severe sensorineural deafness of most utmost point severes patient eardrum auditory ossicular chain all are tantamount to ordinary person, possess good acoustic transformation function.External acoustical signal can obtain the transmission of the high-fidelity and the no profit and loss through this system.Developing the energy transducer of high-effect and a frequency response, is the high-fidelity electroacoustic signal with the chatter conversion of signals of eardrum auditory ossicular chain system, can reach the purpose of picking up external acoustical signal in the body, and in other words, this device can be used as middle ear implanted microphone.
Research and develop above-mentioned middle ear implanted micro microphone, at first will satisfy microminiaturized requirement.Because people's eardrum chamber is footpath 15mm up and down, anteroposterior diameter 13mm, interior external diameter is 6mm at attic, following tympanum 4mm, middle tympanum is narrow, and stenosis is promontory of tympanum and umbo of tympanic membrane opposite position, 2mm only, total measurement (volume) is 1-2ml.In such narrow space, except that auditory ossicular chain, also contain muscle and ligament etc., thereby it is extremely limited to hold the space of implant.Simultaneously, the about 75mg of one-sided auditory ossicular chain gross mass, the heaviest about 38mg of incus wherein, about malleus 32mg, stapes is minimum.The restriction of above-mentioned two aspect reasons makes the microphone that is coupled on the auditory ossicular chain must satisfy light weight, little, the highly sensitive requirement of size.This difficult problem is difficult for solving just, causes the research and development of implanted microphone not obtain the essence breakthrough always.
Because piezoceramic material has high sensitivity, characteristics that frequency response is good; The microphone that adopts piezoelectric ceramic to make is compared with microphones such as electromagnetic type, condenser type, electret, semiconductor-types, has characteristics such as simple in structure, that volume is little, reliability is high, the life-span is long, no magnetic swashs.In recent years; Micro electro mechanical system (MEMS) technology (Micro electromechanical System; MEMS) technology obtains tremendous development, and it utilizes the height integrated technology, and the system integrated chip (SOC) that makes making integrate information gathering, processing, analog-to-digital conversion, Digital Transmission becomes possibility.Adopt the high-performance piezoelectric ceramic to combine the MEMS technology, can significantly dwindle piezoelectric ceramic microphone volume and quality, make it be more suitable for implanting middle ear.Based on above technological means, we have invented integrated miniature middle ear piezoelectric microphone.
Summary of the invention
The objective of the invention is for implantable artificial cochlea system and artificial middle ear system provide a kind of middle ear implanted micro piezoelectric microphone and preparation method thereof entirely.
The middle ear implanted micro piezoelectric microphone of invention can pick up auditory ossicular chain vibroacoustics signal, these acoustic signals that pick up is carried out reallocation stimulates i-coch implant electrode utmost point battle array after the handled, realizes the electric sense of hearing; Perhaps carry out processing and amplifying, be transferred to the artificial middle ear driver of implanted, severe hearing decline patient's hearing in can significantly improving.This middle ear implanted micro piezoelectric microphone can provide the core component support for the research and development of full implantable artificial cochlea or artificial middle ear, and external microphone is built in the body fully.
Figure 377392DEST_PATH_IMAGE001
Adopt the high-performance piezoceramic material; Be made as ultra-thin microstrip piezoelectric ceramic twin lamella; Utilize micro electro mechanical system (MEMS) technology (MEMS); With itself and preposition amplifying and noise reducing Circuits System and becoming one of fixture structure devices, adopt insulation, the moistureproof antistatic of anti-salt, biocompatible materials encapsulation to form simultaneously.This device can be implanted in the middle ear easily, and can be fixed in a plurality of coupling positions of auditory ossicular chain.Its mode of operation is that floated fixed coupling is in auditory ossicular chain; After external acoustical signal vibration eardrum and the auditory ossicular chain system, this microphone is promptly followed the auditory ossicular chain vibration and is produced corresponding forced vibration, behind the piezoelectric ceramic vibrator of conduct vibrations to single cantilever beam structure; Because direct piezoelectric effect; Can the mechanical oscillation that external acoustical signal excites be converted into the signal of telecommunication in real time, be exportable stronger electroacoustic signal after amplifying by preposition amplifying and noise reducing circuit again, thereby become a kind of solution of implanted microphone.The miniature implanted microphone of the present invention's design is through the finite element modelling experiment, and the result shows can pick up test 0.02-20kHz pure tone signal more delicately, and has good frequency response curve.Simultaneously, it also have operation install simple, good biocompatibility, long service life, energy consumption low, be convenient to characteristics such as large-scale production.
Particularly, first aspect the invention provides a kind of middle ear implanted micro piezoelectric microphone, and the version of the implanted piezoelectric microphone of invention is the all-in-one micro device that comprises fixture:.
In second aspect; The invention provides described middle ear implanted micro piezoelectric microphone; Its main components and parts comprise: the piezoelectric ceramic twin lamella; Adopt piezoelectric ceramic highly sensitive, low-quality factor, the utilization new technology is made the bar shaped piezoelectric ceramic twin lamella of long 1.5~4.0mm, wide 0.5~1.0mm, thick 0.2~0.3mm, and quality is less than 7mg.Fixture is combined by fixedly snap ring and retaining collar, and material is a Ultimum Ti.Wherein retaining collar is that the sheet alloy of thick 0.1mm is formed by stacking about wide, the long 0.6~1.5mm of 0.6mm; The fixed card boxing is connected to the middle part of the sheet collar, and snap ring constitutes the about 4mg of fixture total quality by a pair of diameter 0.2mm alloy silk.The integrated printing-type amplifying and noise reducing of MEMS Circuits System chip, this chip size be less than 1.2mm * 0.8mm * 0.05mm, the about 1~2mg of total quality, and Circuits System adopts MEMS technology etch printing on silica-based to form.The circuit leading point is set to the microbonding point.Adopt 1.5~5.0V direct current supply.
Middle ear implanted micro piezoelectric microphone prepares the main technique flow process and comprises:
Step (one): piezoelectric ceramic dual wafer surface preliminary treatment.Tow sides respectively preset microbonding point near center line respectively.
The integrated preposition amplifying and noise reducing circuit system of step (two): MEMS.The special-purpose preposition amplifying and noise reducing circuit of printed design on ultra-thin silicon wafer, and microbonding point in five places is set in the relevant position, be connected with back side pad, face bonding contact, DC power supply input point, signal output point, earth point respectively.
Step (three): micro welding connection circuit and piezoelectric ceramic twin lamella, biogum is pasted and is solidified then.Surface mount process welding each point is also drawn all circuits, with biological curing glue silicon chip and piezoelectric ceramic twin lamella is pasted curing then.
Step (four): with piezoelectric ceramic twin lamella and the insulation of Circuits System vapour deposition Parylene.
Step (five): the microphone circuit exit is inserted in the fixture collar and tightens up the collar, again to solidify the gluing curing that connects.
Step (six): the medical titanium valve of integral device spraying plating thin layer, vapour deposition Parylene again.
The brief description of the process that above-mentioned middle ear implanted micro piezoelectric microphone is made is:
The third aspect; Installation method is implanted in brief introduction: conventional Mastoidotomy rear profile mastoid cavity exposes processus brevis incudis, as sign tympanum after facial recess cuts; Can expose signs such as incudostapedial joint, long process of incus, tympanic cord nerve, with microphone fixing on long limb of incus; Also feasible atticotomy exposes neck of malleus, and microphone snap ring cover is clipped on the neck of malleus; Short limb of incus also is an optional fixed position in addition.
For the ease of understanding, below will describe in detail of the present invention through concrete accompanying drawing and embodiment.What need particularly point out is, instantiation and accompanying drawing only are in order to explain that the applicant can explain according to this paper, within the scope of the invention it is made suitable correction and change, and these corrections and changing are also included in the scope of the present invention.
 
Middle ear implanted micro piezoelectric microphone advantage of the present invention is:
1. process innovation: adopt the surface mount mode to assemble piezoelectric vibrator and circuit, can realize the mechanization pipelining, large-scale production is effectively enhanced productivity; Adopt the Parylene vapour deposition with the insulation-encapsulated integral device, dual packaged can be strengthened anti-salt dampproof effect; Surface spraying plating thin layer titanium valve can disturb by antistatic.Adopt the moistureproof technology of the anti-salt of above-mentioned insulation can also greatly reduce device volume and quality, also can obtain excellent biological compatibility with the antistatic encapsulation.
2. structure innovation: the MEMS technology is combined with the piezoelectric of high electroacoustic performance, and employing piezoelectric vibrator direct surface mounts preposition amplifying and noise reducing circuit methods, has greatly saved assembling space, has reduced device volume and weight effectively.Design easy easy-to-install snap ring shape fixture and band shape external member simultaneously; Can piezoelectric vibrator firmly be fettered is the single cantilever beam structure of an end free vibration; With auditory ossicular chain coupling fixing after, vibration that can the actual induction latter is beneficial to the high efficiency acoustic-electric and transforms.
3. biocompatibility innovation: as the middle ear built-in type device, except that require device whole miniature, also need consider biocompatibility, long-life property, little with the function interference to the physiological structure of biological tissue.Adopt snap ring shape mounting means can reduce tissue contact surface.Because titanium and Parylene have good biocompatibility, the outer encapsulating material that becomes the property implanted device extensive use for many years, so the long-life requirement is also satisfied in difficult generation rejection when directly contacting with auditory ossicular chain.
4. coupled modes innovation:, can select auditory ossicular chain a plurality of positions coupling fixing as single middle ear implanted micro piezoelectric microphone spare.Can select the fixed position flexibly according to implantation person's physical condition in the art, comprise short limb of incus, long limb of incus, neck of malleus etc., device both all heeling-in go in the tympanum, also can be imbedded in the tympanic antrum chamber.
 
Description of drawings
Fig. 1 is a middle ear implanted micro piezoelectric microphone integral device schematic appearance
Fig. 2 is a device critical piece decomposing schematic representation
Fig. 3 is a middle ear implanted micro piezoelectric microphone sketch map
Wherein: 1------fixture, 3---fixture is installed snap ring, 4---installation sleeve loop wire cable comprises the working dc power line, is total to ground wire and output line road, 5, and---------snap ring, 8 is installed at two places, and---collar integral body is carried part, 9, and------------------------------------stapes, 21---is mounted on the midget microphone, 22 on the long process of incus---, and the fixture snap ring fixedly secures midget microphone to incus, 20 to malleus, 19 to eardrum, 18 to piezoelectric ceramic twin lamella, 16 to preposition amplifying and noise reducing Circuits System chip, 15 to piezoelectric ceramic dual wafer surface pretreatment zone, 14 to earth connection microbonding point, 13 to signal output channel microbonding point, 12 to direct current supply path microbonding point, 11 to collar cable, 10 to positive microbonding point, 7 to back side microbonding point, 6 to single cantilever beam structure piezoelectric vibrator, 2 in lead draw-out area, 17.

Claims (7)

1. a middle ear implanted micro piezoelectric microphone is characterized in that: use ultra-thin miniature piezo-ceramic twin lamella as the core energy transducer; Adopt the integrated superminiature microphone device of processing technology manufacturings such as MEMS technology; This device is fixed in the whole tympanum of implanting of mode of auditory ossicular chain (incus or malleus) through coupling; Pick up auditory ossicular chain vibroacoustics signal with floating forced vibration mode; It has characteristics such as excellent biological compatibility, the moistureproof antistatic high s/n ratio of anti-salt wideband response; In simplation verification property modeling Analysis test, it can pick up delicately and can hear auditory ossicular chain vibroacoustics signal due to acoustic frequency 20Hz~20000Hz scope, and has frequency response curve preferably.
2. a kind of middle ear implanted micro piezoelectric microphone manufacture method according to claim 1: earlier specification is carried out surface treatment for long 1.5~3.5mm, wide 0.5~1.0mm, thick 0.15~0.30mm strip thin laminated electroceramics twin lamella; Utilize the MEMS technology to integrate pre-amplification circuit and the encapsulation of fitting in Surface Machining; The Parylene vapour deposition is insulated and is prevented the moistureproof anti-body rejection processing of salt; Combine at last to carry out the medical titanium valve antistatic of surface spraying thin layer again behind the Ultimum Ti fixture; Repeat the Parylene vapour deposition; The MEMS miniature piezoelectric microphone quality of design is not more than 16mg, and full-size is no more than 3.5mm (length) * 1.2mm (wide) * 0.4mm (thick), can combine to be fixed on auditory ossicular chain incus, a plurality of sites of malleus.
3. a kind of middle ear implanted micro piezoelectric microphone according to claim 1; It is characterized in that: realize vibroacoustics signal and electroacoustic signal conversion with floating mode of vibration; All implant tympanum through fixed coupling in the mode of auditory ossicular chain, become full implantation property microphone.
4. a kind of middle ear implanted micro piezoelectric microphone manufacture method according to claim 2; It is characterized in that: adopt processing technology such as MEMS technology with pre-amplification circuit, that memory Nitinol fixture equals the piezoelectric ceramic twin lamella is integrated; The total quality and the volume of device are significantly dwindled; Its quality is no more than 20mg, size is no more than 3.5mm (length) * 1.2mm (wide) * 0.4mm (thick), thus the whole tympanum of implanting.
5. a kind of middle ear implanted micro piezoelectric microphone manufacture method according to claim 2; It is characterized in that: adopt medical titanium to carry out the surface spraying and cover whole microphone with excellent biological compatibility; Can obtain three aspect advantages: both shielded electrostatic interference; Can reduce the rejection of implanting behind the middle ear again, also significantly alleviate the total quality of device.
6. a kind of middle ear implanted micro piezoelectric microphone manufacture method according to claim 2 is characterized in that: twice Parylene vapour deposition packaging technology is that device provides the duplicate protection of insulation with moistureproof anti-salt.
7. a kind of middle ear implanted micro piezoelectric microphone manufacture method according to claim 2; It is characterized in that: piezoelectric microphone spare directly combines minisize memory Nitinol fixture; Can conveniently implant middle ear and be fixed in auditory ossicular chain, reduce the body rejection.
CN2011103056611A 2011-10-11 2011-10-11 Middle-ear implantable miniature piezoelectric microphone and method for preparing same Pending CN102413407A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105959851A (en) * 2016-06-14 2016-09-21 常州市武进晶丰电子有限公司 Ear type treble compensation headphone
CN110166913A (en) * 2018-02-14 2019-08-23 复旦大学附属眼耳鼻喉科医院 Biocompatibility microphone and preparation method thereof
CN110546966A (en) * 2017-02-23 2019-12-06 科利耳有限公司 Transducer placement for growth adaptation
CN111228030A (en) * 2020-03-09 2020-06-05 西安交通大学医学院第一附属医院 Intelligent magnetic traction device for treating OSAS
WO2021018469A1 (en) 2019-07-30 2021-02-04 International Business Machines Corporation Artificial cochlea

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CN101081188A (en) * 2006-05-31 2007-12-05 复旦大学附属眼耳鼻喉科医院 Full-implanting type artificial cochlea and method for making same
CN101577850A (en) * 2009-06-15 2009-11-11 复旦大学附属眼耳鼻喉科医院 Implanted piezoelectric ceramic microphone and manufacturing method thereof
WO2011053674A1 (en) * 2009-10-30 2011-05-05 Vibrant Med-El Hearing Technology Gmbh Implantable signal delivery systems
CN102105192A (en) * 2008-06-13 2011-06-22 耳蜗有限公司 Implantable sound sensor for hearing prostheses

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Publication number Priority date Publication date Assignee Title
US6161046A (en) * 1996-04-09 2000-12-12 Maniglia; Anthony J. Totally implantable cochlear implant for improvement of partial and total sensorineural hearing loss
CN101081188A (en) * 2006-05-31 2007-12-05 复旦大学附属眼耳鼻喉科医院 Full-implanting type artificial cochlea and method for making same
CN102105192A (en) * 2008-06-13 2011-06-22 耳蜗有限公司 Implantable sound sensor for hearing prostheses
CN101577850A (en) * 2009-06-15 2009-11-11 复旦大学附属眼耳鼻喉科医院 Implanted piezoelectric ceramic microphone and manufacturing method thereof
WO2011053674A1 (en) * 2009-10-30 2011-05-05 Vibrant Med-El Hearing Technology Gmbh Implantable signal delivery systems

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105959851A (en) * 2016-06-14 2016-09-21 常州市武进晶丰电子有限公司 Ear type treble compensation headphone
CN105959851B (en) * 2016-06-14 2019-04-19 常州市武进晶丰电子有限公司 In-Ear high pitch compensates earphone
CN110546966A (en) * 2017-02-23 2019-12-06 科利耳有限公司 Transducer placement for growth adaptation
CN110166913A (en) * 2018-02-14 2019-08-23 复旦大学附属眼耳鼻喉科医院 Biocompatibility microphone and preparation method thereof
WO2021018469A1 (en) 2019-07-30 2021-02-04 International Business Machines Corporation Artificial cochlea
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CN111228030A (en) * 2020-03-09 2020-06-05 西安交通大学医学院第一附属医院 Intelligent magnetic traction device for treating OSAS

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Application publication date: 20120411