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CN109246575A - A kind of preparation method of the progressive acoustic impedance matching layer of high frequency - Google Patents

A kind of preparation method of the progressive acoustic impedance matching layer of high frequency Download PDF

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Publication number
CN109246575A
CN109246575A CN201810907838.7A CN201810907838A CN109246575A CN 109246575 A CN109246575 A CN 109246575A CN 201810907838 A CN201810907838 A CN 201810907838A CN 109246575 A CN109246575 A CN 109246575A
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CN
China
Prior art keywords
progressive
acoustic impedance
photoresist
mask plate
high frequency
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CN201810907838.7A
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Chinese (zh)
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CN109246575B (en
Inventor
吴大伟
王黎
陈磊
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Guangzhou Liansheng Electronic Technology Co Ltd
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Guangzhou Liansheng Electronic Technology Co Ltd
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R31/00Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor
    • H04R31/003Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor for diaphragms or their outer suspension
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03FPHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/0035Multiple processes, e.g. applying a further resist layer on an already in a previously step, processed pattern or textured surface
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2231/00Details of apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor covered by H04R31/00, not provided for in its subgroups
    • H04R2231/001Moulding aspects of diaphragm or surround

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • General Physics & Mathematics (AREA)
  • Transducers For Ultrasonic Waves (AREA)

Abstract

The invention discloses a kind of preparation methods of the progressive acoustic impedance matching layer of high frequency, include the following steps: S1: using the mask plate of complementary structure, using two-sided canted exposure method, precisely aligning exposure by litho machine, obtain photoresist progressive structure;S2: matching materials is filled in the photoresist progressive structure, forms progressive acoustic impedance matching layer.The preparation method of the progressive acoustic impedance matching layer of high frequency disclosed by the invention realizes the acoustical match material of micron-scale precision, the acoustical match that can be used for during high frequency ultrasound, and it is high to prepare precision.

Description

A kind of preparation method of the progressive acoustic impedance matching layer of high frequency
Technical field
The present invention relates to a kind of preparation methods of the progressive acoustic impedance matching layer of high frequency.
Background technique
Ultrasonic transducer is a kind of device for being able to achieve electric signal and acoustical signal is mutually converted because it is with piezoelectric effect, It is the acoustical device of core the most in ultrasonic system.
Most of Commercial ultrasound energy converter uses single layer, bilayer or multilayer matching layer at present, wherein single layer matching and bilayer Matching cannot fully achieve the acoustic impedance match between piezoelectric layer and detected object, multi-layer Matched since the matching number of plies is limited Although layered scheme can significantly improvement sound can be to the efficiency of transmission of detected object, with the increase of the matching number of plies, phase The bonding number of plies answered also successively increases, this undoubtedly will increase probe manufacturing process difficulty, uncertainty and its complexity.It is same with this When, multiple reflections of the ultrasonic wave in adhesive layer can enhance therewith, further decrease the overall performance of ultrasonic transducer.If Acoustic impedance with layer is not layer-by-layer variation but gradual change changes, i.e., the size of gradual change matching acoustic impedance is by the gradual change of piezoelectric layer side It crosses to contact layer side, can solve that acoustic energy transmissions efficiency and manufacture craft in multi-layer Matched scheme can't eat one's cake and have it asks Topic.
Acoustic impedance match traditionally is carried out with quarter-wave method, this method can only be realized in centre frequency attachment Best match, impedance progressive layer then can realize acoustic impedance match in broader frequency range.
Also occur acoustic impedance gradual change type ultrasonic transducer on the market at present, but has following defects that
The Chinese patent of Patent No. CN200810038902 proposes a kind of progressive acoustic impedance preparation method, this method It cannot achieve the accurate control progressive to acoustic impedance.
The Chinese patent of Patent No. CN200820151708.7 discloses a kind of ultrasonic transduction of acoustic impedance consecutive variations Device, it is main using a variety of acoustical material particles identical by partial size, specific gravity is different and polymer coupler is mixing cured forms, Under the action of gravity, particle can form acoustic impedance and continuously become according to specific gravity size successively longitudinal arrangement from large to small after solidification The matching layer of change, the program needs various powders, and powder specific gravity needs consecutive variations, and cost of manufacture is high, and difficulty is big.
In the Chinese patent of Patent No. CN201310296746.7, acoustic impedance gradual change is manufactured using gradient temperature solidification method Matching layer, specific implementation are as follows: setting multistage solidification temperature makes the viscosity of resin by thick thinning, and fills material in the process Material is differently formed different sedimentaries according to density, and toward floating, relatively denser powder sinks the small powder of relative density, So that the powder of internal different densities forms the matching layer of acoustic impedance gradual change, but its complex manufacturing process along longitudinal direction, need a variety of The powder and setting multistage solidification temperature of different specific weight, the control of this method temperature is stringent, and curing time is longer.
Summary of the invention
In view of the shortcomings of the prior art, the object of the present invention is to provide a kind of preparation sides of the progressive acoustic impedance matching layer of high frequency Method realizes the acoustical match material of micron-scale precision, the acoustical match that can be used for during high frequency ultrasound, and prepares precision It is high.
To achieve the above object, the present invention provides a kind of preparation methods of the progressive acoustic impedance matching layer of high frequency, including such as Lower step:
S1: using the mask plate of complementary structure, using two-sided canted exposure method, exposure is precisely aligned by litho machine, is obtained To photoresist progressive structure;
S2: matching materials is filled in the photoresist progressive structure, forms progressive acoustic impedance matching layer.
Compared with prior art, the preparation method of the progressive acoustic impedance matching layer of high frequency disclosed by the invention, realizes micro- The acoustical match material of rice dimensional accuracy, the acoustical match that can be used for during high frequency ultrasound, and it is high to prepare precision.
Another specific embodiment according to the present invention, the mask plate of the complementary structure include upper mask plate and lower exposure mask Plate;The upper mask plate is rectangle comprising light transmission group and opaque group, the quadrangle of the upper mask plate are opaque group, institute It states light transmission group and the opaque group of interval is arranged;The lower mask plate is rectangle comprising light transmission group and opaque group, it is described The quadrangle of lower mask plate is light transmission group, and the light transmission group and the opaque group of interval are arranged.
Another specific embodiment according to the present invention, the matching materials include organosilicon.
Another specific embodiment according to the present invention, the step S1 further comprises step S11-S15:
S11: the splash-proofing sputtering metal layer on quartz wafer;
S12: mask plate is made a plate to the metal layer in use;
S13: the spin coating photoresist on the metal layer through the upper mask plate plate-making obtains photoresist layer;
S14: the quartz wafer through gluing is exposed processing;
S15: develop the photoresist layer, obtains photoresist progressive structure.
Another specific embodiment according to the present invention, the step S14 further comprises step S141-S142:
S141: from the ultraviolet canted exposure in quartz wafer bottom;
S142: the lower mask plate is used, from vertical exposure above the photoresist layer.
Another specific embodiment according to the present invention, the step S2 further comprises step S21-S22:
S21: the matching materials is slowly injected into the photoresist progressive structure, and is vacuumized and made the matching materials It is fully infiltrated into the photoresist progressive structure, obtains matching materials progressive structure;
S22: after matching materials solidification, by the matching materials progressive structure from the photoresist progressive structure Removing.
Another specific embodiment according to the present invention further comprises step S23 after the step S22:
Supplementary material is injected in the matching materials progressive structure, forms progressive acoustic impedance micro-structure.
Another specific embodiment according to the present invention, the photoresist are SU-8 photoresist.
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.
Detailed description of the invention
Fig. 1 is the flow chart of the preparation method for the progressive acoustic impedance matching layer of high frequency that embodiment 1 provides;
Fig. 2 is the flow chart of step S1 in the preparation method for the progressive acoustic impedance matching layer of high frequency that embodiment 1 provides;
Fig. 3 is the flow chart of step S2 in the preparation method for the progressive acoustic impedance matching layer of high frequency that embodiment 1 provides.
Specific embodiment
Embodiment 1
It is the flow chart of the preparation method of the progressive acoustic impedance matching layer of high frequency provided in this embodiment referring to Fig. 1.This method Including step S1-S2:
S1: using the mask plate of complementary structure, using two-sided canted exposure method, exposure is precisely aligned by litho machine, is obtained To photoresist progressive structure.
The step is for obtaining photoresist progressive structure.
Specifically, in this step, the mask plate of complementary structure includes upper mask plate and lower mask plate;Upper mask plate is square Shape comprising light transmission group and opaque group, the quadrangle of upper mask plate are opaque group, and light transmission group is arranged with opaque group of interval; Lower mask plate is rectangle comprising light transmission group and opaque group, the quadrangle of lower mask plate are light transmission group, light transmission group with opaque group Interval setting.Upper mask plate and lower mask plate are that complementary structure looks like are as follows: in the light transmission group and lower mask plate of upper mask plate Opaque group is correspondingly arranged, and opaque group in upper mask plate is correspondingly arranged with the light transmission group in lower mask plate.
Fig. 2 is the flow chart of step S1 in the preparation method of the progressive acoustic impedance matching layer of high frequency provided in this embodiment;Step Rapid S1 further comprises step S11-S15:
S11: the splash-proofing sputtering metal layer on quartz wafer.
The step forms metal layer for sputtering.
S12: mask plate is made a plate to metal layer in use.
The step is used to carry out exposure mask plate-making to metal layer using upper mask plate.
S13: the spin coating photoresist on the metal layer made a plate through upper mask plate obtains photoresist layer.
The step is used for spin coating photoresist, obtains photoresist layer.In the present embodiment, photoresist uses SU-8 photoresist.
S14: the quartz wafer through gluing is exposed processing.
The step is for being exposed processing, and further, which includes S141-S142:
S141: from the ultraviolet canted exposure in quartz wafer bottom;
S142: lower mask plate, the vertical exposure above photoresist layer are used.
S15: lithographic glue-line obtains photoresist progressive structure.
The step is used for development treatment, obtains photoresist progressive structure.
S2: filling matching materials in photoresist progressive structure, forms progressive acoustic impedance matching layer.
The step forms progressive acoustic impedance matching layer for filling.
Fig. 3 is the flow chart of step S2 in the preparation method of the progressive acoustic impedance matching layer of high frequency provided in this embodiment.Tool Body, step S2 further comprises step S21-S23:
S21: matching materials is slowly injected into photoresist progressive structure, and vacuumizing makes matching materials be fully infiltrated into photoetching In glue progressive structure, matching materials progressive structure is obtained;
S22: after material solidification to be matched, matching materials progressive structure is removed from photoresist progressive structure.
S23: injecting supplementary material in matching materials progressive structure, forms progressive acoustic impedance micro-structure.
In the present embodiment, matching materials includes PDMS, i.e. dimethyl silicone polymer, referred to as organosilicon.
The preparation method of the progressive acoustic impedance matching layer of high frequency disclosed in the present embodiment, realizes the sound of micron-scale precision Matching materials, the acoustical match that can be used for during high frequency ultrasound are learned, and it is high to prepare precision.
Although the present invention is disclosed above in the preferred embodiment, it is not intended to limit the invention the range of implementation.Any The those of ordinary skill in field is not departing from invention scope of the invention, improves when can make a little, i.e., all according to this hair Bright done same improvement, should be the scope of the present invention and is covered.

Claims (8)

1. a kind of preparation method of the progressive acoustic impedance matching layer of high frequency, which comprises the steps of:
S1: using the mask plate of complementary structure, using two-sided canted exposure method, exposure is precisely aligned by litho machine, obtains light Photoresist progressive structure;
S2: matching materials is filled in the photoresist progressive structure, forms progressive acoustic impedance matching layer.
2. the preparation method of the progressive acoustic impedance matching layer of high frequency as described in claim 1, which is characterized in that the complementary structure Mask plate include upper mask plate and lower mask plate;The upper mask plate is rectangle comprising light transmission group and opaque group, it is described The quadrangle of upper mask plate is opaque group, and the light transmission group and the opaque group of interval are arranged;The lower mask plate is rectangle, It includes light transmission group and opaque group, and the quadrangle of the lower mask plate is light transmission group, the light transmission group and it is opaque group described between Every setting.
3. the preparation method of the progressive acoustic impedance matching layer of high frequency as described in claim 1, which is characterized in that the matching materials Including organosilicon.
4. the preparation method of the progressive acoustic impedance matching layer of high frequency as claimed in claim 2, which is characterized in that the step S1 into One step includes step S11-S15:
S11: the splash-proofing sputtering metal layer on quartz wafer;
S12: mask plate is made a plate to the metal layer in use;
S13: the spin coating photoresist on the metal layer through the upper mask plate plate-making obtains photoresist layer;
S14: the quartz wafer through gluing is exposed processing;
S15: develop the photoresist layer, obtains photoresist progressive structure.
5. the preparation method of the progressive acoustic impedance matching layer of high frequency as claimed in claim 4, which is characterized in that the step S14 Further comprise step S141-S142:
S141: from the ultraviolet canted exposure in quartz wafer bottom;
S142: the lower mask plate is used, from vertical exposure above the photoresist layer.
6. the preparation method of the progressive acoustic impedance matching layer of high frequency as claimed in claim 4, which is characterized in that the step S2 into One step includes step S21-S22:
S21: the matching materials is slowly injected into the photoresist progressive structure, and vacuumizing keeps the matching materials abundant It penetrates into the photoresist progressive structure, obtains matching materials progressive structure;
S22: after matching materials solidification, the matching materials progressive structure is shelled from the photoresist progressive structure From.
7. the preparation method of the progressive acoustic impedance matching layer of high frequency as claimed in claim 6, which is characterized in that in the step Further comprise step S23 after S22:
Supplementary material is injected in the matching materials progressive structure, forms progressive acoustic impedance micro-structure.
8. the preparation method of the progressive acoustic impedance matching layer of high frequency as claimed in claim 4, which is characterized in that the photoresist is SU-8 photoresist.
CN201810907838.7A 2018-08-09 2018-08-09 Preparation method of high-frequency progressive acoustic impedance matching layer Expired - Fee Related CN109246575B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111447535A (en) * 2020-03-20 2020-07-24 中国科学院声学研究所 Gradient-adjustable acoustic impedance matching layer

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US20130195333A1 (en) * 2012-01-31 2013-08-01 General Electric Company Method for Forming a Graded Matching Layer Structure
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CN105381943A (en) * 2015-10-14 2016-03-09 深圳市理邦精密仪器股份有限公司 Ultrasonic transducer, gradual-change sound impedance matching layer and manufacturing method of gradual-change sound impedance matching layer
CN107534815A (en) * 2015-02-24 2018-01-02 爱飞纽医疗机械贸易有限公司 Ultrasonic transducer and its manufacture method including the matching layer with composite construction
CN107999362A (en) * 2016-11-01 2018-05-08 深圳市理邦精密仪器股份有限公司 The production method of matching layer
CN108372095A (en) * 2018-03-01 2018-08-07 西安电子科技大学 A kind of matching layer and its manufacturing method of ultrasonic transducer

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CN1756955A (en) * 2003-03-04 2006-04-05 茹瓦·皮尔斯·琼斯 Apparatus and method with matched acoustic impedance
CN201261009Y (en) * 2008-08-07 2009-06-24 上海爱培克电子科技有限公司 Supersonic transducer with continuously changed acoustic impedance
CN102087471A (en) * 2009-12-08 2011-06-08 上海华虹Nec电子有限公司 Method for improving photoetching critical dimension in groove process
US20130195333A1 (en) * 2012-01-31 2013-08-01 General Electric Company Method for Forming a Graded Matching Layer Structure
CN202873061U (en) * 2012-07-24 2013-04-10 常州波速传感器有限公司 Gradual-changing transitional acoustic impedance matching layer
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CN107534815A (en) * 2015-02-24 2018-01-02 爱飞纽医疗机械贸易有限公司 Ultrasonic transducer and its manufacture method including the matching layer with composite construction
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111447535A (en) * 2020-03-20 2020-07-24 中国科学院声学研究所 Gradient-adjustable acoustic impedance matching layer
CN111447535B (en) * 2020-03-20 2021-02-09 中国科学院声学研究所 Gradient-adjustable acoustic impedance matching layer

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