Summary of the invention
The technical problem to be solved by the present invention is at least part of for existing pliable pressure sensor array lacksIt falls into, a kind of pliable pressure sensor array and preparation method thereof and the component for knee joint pressure measurement is provided.
In order to solve the above-mentioned technical problems, the present invention provides a kind of preparation method of pliable pressure sensor array, packetsInclude following steps:
Silicon resistor is patterned by photoetching and etching on SOI Substrate；
Silicon dioxide layer is grown on SOI Substrate after photoetching, as buffering and protective layer；
Patterned silicon resistor injects boron ion under to silicon dioxide layer, and carries out heavy doping in end positions to form siliconThe ohmic contact regions of resistor stripe；
Electrode window through ray is opened above the ohmic contact regions of every silicon resistor item by photoetching；
Sputter conductive material, on the ohmic contact regions at every silicon resistor both ends preparation contact electrode, and prepare and itsIn first contact electrode connection lower layer's lead；
Parylene dielectric layer is grown to cover resistor stripe；
By lithography and etching, the region of corresponding second contact electrode prepares fairlead on Parylene dielectric layer；
Conductive material is sputtered, and prepares the upper layer lead connecting with the second contact electrode；
In device upper surface spin-on polyimide, the first polyimides clad is formed after successively solidifying by temperature gradient；
Upper surface is carried out by temporarily bonding glue on the first polyimides clad to be temporarily bonded；
The buried oxide layer and substrate of SOI Substrate below removal devices；
It is successively sub- by the second polyamides is formed in device bottom surface after temperature gradient solidification in device lower surface spin-on polyimideAmine clad；
It releases upper surface to be temporarily bonded, obtains pliable pressure sensor array.
In the preparation method of pliable pressure sensor array according to the present invention, it is preferable that described to silicon resistorMultiple rows of silicon resistor item is defined after being patterned, the first contact electrode of every row's silicon resistor item passes through parallel upper layer busbarIt draws, the extending direction of every silicon resistor item is consistent and perpendicular to the upper layer busbar connected, and the second of every row's silicon resistor itemIt contacts electrode to draw by parallel lower layer's busbar, the extending direction of lower layer's busbar is parallel to the silicon resistor item.
In the preparation method of pliable pressure sensor array according to the present invention, it is preferable that the preparation methodIn by cutting the buried oxide layer and silicon substrate of the SOI Substrate below thin polishing process removal devices.
In the preparation method of pliable pressure sensor array according to the present invention, it is preferable that the preparation methodIn after spin-on polyimide, successively according to following temperature gradient solidify:
First stage: solidify 10-40min at 60~90 DEG C；
Second stage: solidify 10-40min at 110~130 DEG C；
Phase III: solidify 10-40min at 150-180 DEG C；
Fourth stage: solidify 0-20min at 190~200 DEG C；
5th stage: solidify 10-40min at 210~230 DEG C；
6th stage: solidify 10-40min at 240~260 DEG C.
In the preparation method of pliable pressure sensor array according to the present invention, it is preferable that the SOI Substrate packetInclude pentagonal array area and rectangular lead district；It is described silicon resistor is patterned after multiple rows of silicon resistor item position for definingIn array area, and the arrangement interval of every row's silicon resistor item is equal.
In the preparation method of pliable pressure sensor array according to the present invention, it is preferable that the conductive materialFor Ti/Au.
The present invention also provides a kind of pliable pressure sensor arrays, are prepared using foregoing method.Institute of the present inventionThe pliable pressure sensor array stated can be used for the prosthetic surface pressure measurement of knee joint, joint of vertebral column or hip joint.
The present invention also provides a kind of components for knee joint pressure measurement, comprising:
Knee-joint prosthesis, the knee-joint prosthesis include femoral prosthesis, tibial prosthesis and are installed on the tibial prosthesisThe gasket of side, the upper surface of the gasket offers piece shape slot；
The pliable pressure sensor array of method preparation as described above, is set in the piece shape slot of the gasket.
In the component according to the present invention for knee joint pressure measurement, it is preferable that described shape slot includes: interiorSide condyle slot and external condyle slot；And the cabling channel extended respectively to two sides from entocondyle slot and external condyle slot.
Implement pliable pressure sensor array and preparation method of the invention, has the advantages that use of the present inventionThe good material of the mechanical performances such as polyimides and Parylene, bio-compatibility carries out array of pressure sensorsCladding guarantees its flexible and bio-compatibility, and accordingly provides a set of step of preparation process, can satisfy such as knee jointThe measurement request of pressure distribution.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present inventionIn attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment isA part of the embodiments of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill peopleMember's every other embodiment obtained without making creative work, shall fall within the protection scope of the present invention.
The various structural schematic diagrams according to the embodiment of the present disclosure are shown in the attached drawings.These figures are not drawn to scale, wherein some details are magnified for the purpose of clear expression, and some details may be omitted.It is shown in the drawingsVarious regions, the shape of layer and relative size, positional relationship between them are merely exemplary, in practice may be due to systemIt makes tolerance or technical restriction and is deviated, and those skilled in the art may be additionally designed as required with differenceShape, size, the regions/layers of relative position.
In the context of the disclosure, when one layer/element is referred to as located at another layer/element "upper", which canMay exist intermediate layer/element on another layer/element or between them.In addition, if in a kind of directionIn one layer/element be located at another layer/element "upper", then when turn towards when, which can be located at another layer/memberPart "lower".
Referring to Fig. 1, for according to the pliable pressure sensor array planar structure schematic diagram of the preferred embodiment of the present invention.PleaseIn conjunction with refering to Fig. 2 to Figure 15, the preparation process flow for the pliable pressure sensor array according to the preferred embodiment of the present invention is shownIt is intended to.The embodiment provide pliable pressure sensor array preparation method the following steps are included:
(1) SOI Substrate is provided as shown in Figure 2, and silicon resistor is patterned by photoetching on the SOI Substrate, such asShown in Fig. 3.Wherein SOI Substrate includes silicon resistor layer, buried oxide layer 2 and silicon substrate 3.Silicon resistor layer forms graphically after photoetchingSilicon resistor, including more silicon resistor items 1.The single silicon resistor size of photoetching are as follows: a length of 200~1000um, width be 10~100um, 50~500um of resistor stripe distance.Preferably, the SOI Substrate that the present invention selects includes pentagonal array area 13With rectangular lead district 14, the multiple rows of silicon resistor item 1 defined after being patterned to silicon resistor is located at array area 13, and every rowThe arrangement interval of silicon resistor item 1 is equal.Preferably, pentagonal array area 13 be rectangle unfilled corner design, with knee jointProsthese shape adaptation.
(2) silicon dioxide layer 4 is grown on the SOI Substrate after photoetching, as buffering and protective layer, as shown in Figure 4.
(3) boron ion is injected to silicon resistor patterned under silicon dioxide layer, and carries out heavy doping in end positions with shapeAt the ohmic contact regions 5 of silicon resistor item 1, as shown in Figure 5.Ohmic contact regions 5 can reduce between metal lead wire and silicon resistor itemContact resistance.Silicon resistor item 1 is formed by adulterating B ion, and silicon dioxide layer 4 above works as a buffer.Preferably, shouldThe B of silicon resistor item in step+Dopant dose is 2E13~5E14, and Implantation Energy is 50~180Kev；Silicon resistor both ends ohmThe B of contact area+Dopant dose is 2E15~5E16, and Implantation Energy is 50~180Kev；In injection B+After anneal, temperatureDegree is 800~1050 DEG C, and the time is 3h~for 24 hours, and entire annealing process uses N2Atmosphere.
(4) electrode window through ray is opened above the ohmic contact regions of every silicon resistor item 15 by photoetching, as shown in Figure 6.
(5) conductive material is sputtered, the preparation contact electrode on the ohmic contact regions 5 at every silicon resistor both ends, including theOne contact electrode 61 and the second contact electrode 62, and the lower layer's lead 63 connecting with the wherein first contact electrode 61 is prepared, such as Fig. 7It is shown.Preferably, which is Ti/Au.Ti/Au is by titanium and gold collectively as electrode and lead material, wherein titaniumAdhesiveness between bottom, enhancing and silicon, gold is on upper layer.The thickness of Ti is aboutThe thickness of Au is then
(6) in device upper surface growth Parylene (Parylene) dielectric layer 7 to cover resistor stripe and lower layer's lead63 etc., as shown in Figure 8.Preferably, the parylene dielectric layer 7 generated in the step with a thickness of 2~3um.
(7) by photoetching and etching, the region preparation of corresponding second contact electrode 62 is drawn on Parylene dielectric layer 7String holes, as shown in Figure 9.
(8) conductive material is sputtered, and prepares the upper layer lead 64 connecting with the second contact electrode 62, as shown in Figure 10.It is poly-Paraxylene dielectric layer 7 plays the role of that upper layer lead 64 and lower layer's lead 63 is isolated, while having good biocompatibility.
Above-mentioned upper layer lead 64 includes more parallel upper layer busbars, and lower layer's lead 63 includes under more parallelLayer busbar.Correspondingly, multiple rows of silicon resistor item 1, every row's silicon resistor are defined after being patterned in abovementioned steps to silicon resistorFirst contact electrode 61 of item 1 is drawn by parallel upper layer busbar, and the extending direction of every silicon resistor item is consistent and verticalIn the upper layer busbar connected.Second contact electrode 62 of every row's silicon resistor item is drawn by parallel lower layer's busbar, underThe extending direction of layer busbar is parallel to the silicon resistor item 1.Lead and lower layer's lead are arranged in parallel lead district 14 at the middle and upper levels.ThisInvention is routed by ranks upper layer and lower layer, and is drawn from the same side, reduces lead footprint area, while meeting measurement demand.
(9) at device upper surface spin-on polyimide (PI), the first polyimides is formed after successively solidifying by temperature gradientClad 8, as shown in figure 11.
(10) it carries out upper surface by temporarily bonding glue on the first polyimides clad 8 to be temporarily bonded, as shown in figure 12.Such as first polyimides clad 8 is adhered on the silicon backing wafer with a thickness of 400um by being temporarily bonded glue 9.
(11) buried oxide layer 2 and silicon substrate 3 of the SOI Substrate below removal devices, as shown in figure 13.Preferably, the stepIn by cutting the buried oxide layer 2 and silicon substrate 3 of the SOI Substrate below thin polishing process (CMP) removal devices.
(12) successively poly- by forming second in device bottom surface after temperature gradient solidification in device lower surface spin-on polyimideAcid imide clad 12, as shown in figure 14.
(13) it releases upper surface to be temporarily bonded, obtains pliable pressure sensor array, as shown in figure 15.
Present invention is alternatively directed to the curing process of used polyimides to be studied.Preferably, it is walked in the above methodSuddenly (9) and (12) successively solidify according to following temperature gradient after spin-on polyimide: the first stage: solid at 60~90 DEG CChange 10-40min；Second stage: solidify 10-40min at 110~130 DEG C；Phase III: solidify 10- at 150-180 DEG C40min；Fourth stage: solidify 0-20min at 190~200 DEG C；5th stage: solidify 10-40min at 210~230 DEG C；6th stage: solidify 10-40min at 240~260 DEG C.From down to height, polyimides is continuously passing through above-mentioned six phase temperaturesCross the above process can achieve solidification bond effect well later.The present invention also provides a kind of pliable pressure sensor arraysColumn are prepared using foregoing method.The pliable pressure sensor array can be used for knee joint, joint of vertebral column or hip jointProsthetic surface pressure measurement.
The present invention further correspondingly provides a kind of component for knee joint pressure measurement, includes at least: knee-joint prosthesis andForegoing pliable pressure sensor array.
Figure 16 is please referred to, for according to knee joint in the knee-joint prosthesis surface pressure measurement component of the preferred embodiment of the present inventionThe scheme of installation of prosthese.As shown in the figure, wherein knee-joint prosthesis includes femoral prosthesis 10, tibial prosthesis 20 and gasket 30.StockBone prosthese 10 is installed on 40 distal end of femur after osteotomy, lower surface form and distal femur form one individual before bone-culting operationIt causes, knee joint three-dimensional digitalization model can be established, and be based on the knee joint by the medical image data of previously-scanned individualThree-dimensional digitalization model carries out virtual osteotomy operation, to design personalized femoral prosthesis.Tibial prosthesis 20 is otherwise known asShin bone metal support, 50 proximal end of shin bone after being installed on osteotomy.Tibial prosthesis 20 and gasket 30 are according to before the individual osteotomy of installationProximal tibia shape and design, and by carrying out the personalized prosthese designed after virtual osteotomy operation to shin bone model.ItsThe configuration of surface of the femoral prosthesis 10 of the upper surface form and design of middle gasket 30 matches.Gasket 30 is installed on tibial prosthesis 30Top, and the upper surface of gasket 30 offers piece shape slot 31.Gasket 30 preferably uses ultra high molecular polyethylene gasket.Pliable pressureSensor array is set in the piece shape slot 31 of gasket 30.The Zhou Jing of gasket 30 is consistent with the tibial plateau size of installation individual.The bone surface of actual tibial platform possesses many concaveconvex structures, the form of ultra high molecular polyethylene gasket surface of the inventionIt is that production is gone on the basis of sufficiently imitating original bone surface form and on the basis of prosthese stability Design.This field basePlinth technical staff is known and can design the configuration of surface of the gasket 30, therefore is no longer repeated.
The shape of pliable pressure sensor array 100 is consistent with the piece shape groove shape of gasket 30, for example, by bioadhesiveMode, adhere to 30 surface of gasket, realize postoperative in living animal joint replacement, the mechanics of knee joint surface prosthese is distributedMeasurement.Pliable pressure sensor array is placed on knee-joint prosthesis surface by the present invention, it is possible to reduce the interference of prosthetic material,Improve the accuracy of measurement result.
Figure 17 is please referred to, to pad according in the knee-joint prosthesis surface pressure measurement component of the preferred embodiment of the present inventionThe structure chart of piece.The upper surface of gasket 30 is consistent with the tibial plateau surfaces form of installation individual, each position in piece shape slot 31Thickness it is equal, and the bottom surface radian of piece shape slot 31 is consistent with the radian of tibial plateau surfaces corresponding position.Piece shape slot includes: interiorSide condyle slot 311 and external condyle slot 312；And the cabling channel extended respectively to two sides from entocondyle slot 311 and external condyle slot 312313.Entocondyle slot 311 and external condyle slot 312 are distributed in the position of corresponding shin bone protuberance two sides, and size can be according to installationThe tibial plateau size of body is adjusted.In a preferred embodiment of the invention, entocondyle slot 311 and external condyle slot 312 are inPentagon, this pentagon cover knee joint surface stress area preferably close to ultra high molecular polyethylene edge, the face of each slotProduct is 70mm2 or so, i.e., the length of maximum long side is about 12mm, and front and back bottom edge is respectively 4mm, 7mm.The thickness of the piece shape slot 31Preferred 200um is spent, on the basis of guaranteeing that the tough band width of sensor array sensibility and its covering material requires, is utmostly protectedThe integrality of the structure of original ultra high molecular polyethylene gasket has been held, is provided for detection knee-joint prosthesis surface biological mechanics most trueReal reliable data result.Although give piece shape slot 31 in the embodiment specifically opens up form, this field basis skillArt personnel, which can according to need, to be adjusted.The present invention not only combines PI, parylene material with SOI, is prepared by PIAnd the heavy doping monocrystalline silicon resistance strip array of parylene layers of cladding, according further to the requirement of knee joint pressure test, to its battle arrayColumn distribution, shape etc. have been carried out for design；It is advantageous that can match very well with knee joint measurement environment, has lifeObject compatibility, possesses certain application prospect in experiment made on the living.
The knee joint that pliable pressure sensor array of the invention can lead to experimental subjects by lead is subcutaneous, and ties upIt is scheduled on FPC circuit board, single-chip microcontroller and wireless communication module outside knee joint to be connected, and signal is exported to the end PC, intoRow is as the result is shown.The silicon force sensing resistance item of heavy doping is when by extraneous pressure in pliable pressure sensor array of the inventionDeformation can be generated, internal stress will lead to resistivity and change, and so as to cause the change in resistance of silicon force sensing resistance item, pass through surveyThe change in resistance for measuring silicon force sensing resistance strip array can obtain extraneous pressure distribution.Therefore, when femur applies pressure to kneeWhen articular prosthesis surface, pliable pressure sensor array senses that ambient pressure changes, and generates corresponding signal, utilizes single-chip microcontrollerThe data signal acquisition process of pliable pressure sensor array is controlled, and signal collected is passed by FPC circuit boardIt is defeated.Signal, using wireless communication module, transmits a signal to the progress of the end PC after through being further processed of one-chip computer moduleIt collects and intuitive display.
In conclusion can be transported the present invention provides a kind of pliable pressure sensor array and using the component of the arrayFor in experiment made on the living, measuring for example personalized knee-joint prosthesis surface pressure distribution.Wherein using PI (polyimides) andThe good material of mechanical performances, the bio-compatibilities such as Parylene (Parylene), wraps array of pressure sensorsIt covers, guarantees its flexible and bio-compatibility, meet experiment made on the living condition.And the present invention utilizes MEMS processing technology, passes throughSOI piece is prepared into the monocrystalline silicon force sensing resistance strip array of heavy doping, measured to pressure by certain process.With it is existingTechnology is compared, and in order to meet the measurement request of knee joint pressure distribution, there is different lithography layouts, techniques to walk by the present inventionSuddenly, parameter and rapidoprint etc..Due to conducting polymer, polyester material Young's modulus much smaller than monocrystalline silicon resistor stripe withAnd PI material, so when in face of external larger pressure on an equal basis, the deformation quantity meeting of pliable pressure sensor array of the inventionSmaller, opposite hysteresis and measurable process performance can be more preferable, and furthermore its piezoresistance coefficient of the monocrystalline silicon resistor stripe of heavy doping is big, electricityResistance changing value is obvious, and accuracy also can be higher.Therefore, sensor of the invention is small in size, and long service life, measurable process is big,Measurement area, density are big, and the performances such as hysteresis are more preferable.Above-mentioned pliable pressure sensor array and use of the invention shouldThe size of the component of array is suitable for animal Beagle dog knee joint, and when being applied to different organisms, size can be according to needIt designs.
Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；AlthoughPresent invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that: it still may be usedTo modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features；And these are modified or replaceed, technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution spirit andRange.