WO2018140972A1 - Dispositifs multicouches et procédés de fabrication - Google Patents

Dispositifs multicouches et procédés de fabrication Download PDF

Info

Publication number
WO2018140972A1
WO2018140972A1 PCT/US2018/016029 US2018016029W WO2018140972A1 WO 2018140972 A1 WO2018140972 A1 WO 2018140972A1 US 2018016029 W US2018016029 W US 2018016029W WO 2018140972 A1 WO2018140972 A1 WO 2018140972A1
Authority
WO
WIPO (PCT)
Prior art keywords
green sheets
preform
sheets
green
binder
Prior art date
Application number
PCT/US2018/016029
Other languages
English (en)
Inventor
Joseph Capobianco
Christian Martorano
Daniel Declement
Original Assignee
TBT Group, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by TBT Group, Inc. filed Critical TBT Group, Inc.
Publication of WO2018140972A1 publication Critical patent/WO2018140972A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/46—Manufacturing multilayer circuits
    • H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
    • H05K3/4626—Manufacturing multilayer circuits by laminating two or more circuit boards characterised by the insulating layers or materials
    • H05K3/4629—Manufacturing multilayer circuits by laminating two or more circuit boards characterised by the insulating layers or materials laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/602—Making the green bodies or pre-forms by moulding
    • C04B2235/6025—Tape casting, e.g. with a doctor blade
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/605—Making or treating the green body or pre-form in a magnetic field
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/612—Machining
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/62—Forming laminates or joined articles comprising holes, channels or other types of openings
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/68—Forming laminates or joining articles wherein at least one substrate contains at least two different parts of macro-size, e.g. one ceramic substrate layer containing an embedded conductor or electrode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/48—Manufacture or treatment of parts, e.g. containers, prior to assembly of the devices, using processes not provided for in a single one of the subgroups H01L21/06 - H01L21/326
    • H01L21/4814—Conductive parts
    • H01L21/4846—Leads on or in insulating or insulated substrates, e.g. metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/48—Manufacture or treatment of parts, e.g. containers, prior to assembly of the devices, using processes not provided for in a single one of the subgroups H01L21/06 - H01L21/326
    • H01L21/4814—Conductive parts
    • H01L21/4846—Leads on or in insulating or insulated substrates, e.g. metallisation
    • H01L21/4867—Applying pastes or inks, e.g. screen printing
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/06—Lamination
    • H05K2203/068—Features of the lamination press or of the lamination process, e.g. using special separator sheets
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/46—Manufacturing multilayer circuits
    • H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
    • H05K3/4638—Aligning and fixing the circuit boards before lamination; Detecting or measuring the misalignment after lamination; Aligning external circuit patterns or via connections relative to internal circuits

Definitions

  • the present disclosure relates, generally, to micro-scale and nano-scale multilayer devices ("MLD”) and methods of manufacturing the same.
  • MLD micro-scale and nano-scale multilayer devices
  • a method of manufacturing a multilayer device comprising: tape casting a slurry comprising a ceramic powder and a binder to form a plurality of green sheets; forming one or more of the plurality of green sheets into a desired shape; depositing a circuitry pattern onto one or more of the plurality of green sheets; laminating the plurality of green sheets with each green sheet at least partially overlapping at least one adjacent green sheet; and cofiring the laminated plurality of green sheets to form the multilayer device.
  • depositing a circuitry pattern comprises printing at least one of electrodes, wiring, and via fillings onto the one or more of the plurality of green sheets.
  • aligning comprises stacking the at least two of the plurality of green sheets such that portions of the circuitry pattern on each of the at least two of the plurality of green sheets are connected with each other.
  • a multilayer cantilever preform comprising: a preform stack including a plurality of sheets stacked together such that adjacent sheets at least partially overlap, each of the plurality of sheets comprising ceramic; and a circuitry pattern arranged on one or more of the plurality of sheets; wherein at least one cantilever arm is defined by at least a portion of the preform stack, the at least one cantilever arm including at least one piezoelectric layer and at least one non-piezoelectric layer.
  • a multilayer cantilever green preform comprising: a preform stack including a plurality of green sheets stacked together such that adjacent green sheets at least partially overlap, each of plurality of green sheets comprising ceramic and a binder dissolved in a solvent; and a circuitry pattern arranged on one or more of the plurality of green sheets; wherein at least one cantilever arm is defined by at least a portion of the preform stack, the at least one cantilever arm including at least one piezoelectric layer and at least one non- piezoelectric layer.
  • FIG. 1 is a simplified diagram illustrating one embodiment of a piezoelectric microcantilever sensor ("PEMS");
  • FIG. 2 is a series of simplified diagrams illustrating deformation of the PEMS of
  • FIG. 1 under the influence of an electric field
  • FIG. 3 is a simplified flow diagram illustrating one embodiment of a method of manufacturing MLD
  • FIG. 4 is a simplified diagram illustrating one embodiment of a tape casting process
  • FIG. 5 is a series of simplified diagrams illustrating several embodiments of
  • MLD incorporating one or more cantilevers
  • FIG. 6 is a series of simplified diagrams illustrating one embodiment of electroconductive patterning for an MLD incorporating a single cantilever
  • FIG. 7 is a series of simplified diagrams illustrating one embodiment of electroconductive patterning for an MLD incorporating a cantilever array
  • FIG. 8 is a series of simplified diagrams illustrating embodiments of MLD incorporating clamped cantilevers.
  • references in the specification to "one embodiment,” “an embodiment,” “an illustrative embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may or may not necessarily include that particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
  • FIG. 1 one illustrative embodiment of a PEMS 100 is shown in a simplified diagram.
  • the PEMS 100 shown in FIG. 1 has a length, L, and a width, w, and comprises a piezoelectric layer of thickness tp, density, rp, and Young's modulus Yp, and a non-piezoelectric layer of thickness tn, density, rn, and Young's modulus Yn. Because of the converse piezoelectric effect, when an electric field is applied to the polarization (thickness) direction of the piezoelectric layer, it will elongate or shrink along the length and width directions.
  • the non-piezoelectric layer does not deform thereby constraining the movement of the piezoelectric layer and resulting in bending of the cantilever structure, as illustrated in FIG. 2.
  • an AC field is applied to the PEMS 100, it will bend up and down resulting in flexural (bending) vibration.
  • the ith-mode flexural resonance frequency, f may be written as:
  • M e the effective mass
  • k the spring constant
  • the spring constant, k may be written as:
  • the resonance frequency of the PEMS 100 can be measured by electrical means.
  • the cantilever behaves as a capacitor with a phase angle close to -90°.
  • the in-phase flexural motion gives rise to a peak in the real part, Re(Z), of the electrical impedance, and hence a peak in the phase angle.
  • the shape of this phase angle vs frequency curve is a measure of device performance. Generally speaking, sharper curves allow for more accurate and repeatable device performance.
  • the Q factor of a resonator is a measure of the strength of the damping of its oscillations.
  • the Q factor via resonance bandwidth may be defined as the ratio of the resonance frequency v 0 and the full width at half-maximum (“FWFDVI”) bandwidth ⁇ of the resonance such that:
  • MLD may be manufactured using techniques and methodologies similar to those which are used to produce high temperature cofired ceramics (HTCC) and low temperature cofired ceramics (LTCC). Such MLD may be utilized in biosensors, energy harvesters, and actuators, among other applications.
  • HTCC high temperature cofired ceramics
  • LTCC low temperature cofired ceramics
  • the method 300 generally involves tape casting individual sheets, which are subsequently, cut, electroded, laminated, and sintered.
  • the method 300 is suitable for reproducible, high-volume production of MLD with thinner piezoelectric layers.
  • the method 300 may involve additional and/or different steps to those illustrated in FIG. 3.
  • the method 300 may also involve cold isostatic pressing for the laminated tapes, resulting in higher green density in order to reproducibly control sintering shrinkage.
  • additional machining of the MLD can be used to further tailor the geometries of the MLD (e.g., if near net form shrinkage is obtained).
  • the first several steps of the method 300 relate to formation of a slurry for the tape casting process.
  • the slurry components generally consist of ceramic powders, dispersants, polymeric binders, solvents, and plasticizers. The balance between the ratios of these components facilitates control of material performance and shrinkage, which ultimately dictate final device performance.
  • Slurry preparation begins with mixing ceramic powders in the presence of solvent and dispersing agent in order to reduce the powder agglomerates to the primary particles and coat each primary particle with a steric barrier, such as in a non-aqueous dispersion. Due to the surface chemistry (the interaction of the ceramic particles with the solvents), dispersing agents, such as polymeric dispersants and dispersing resins, can be incorporated to facilitate wetting, deagglomeration, and stability. In addition to dispersing agents, various milling and mixing techniques may be employed to break down the agglomerates (e.g., ball milling, bead milling, attrition milling, etc.).
  • Ceramic powders have been traditionally prepared by solid-state reaction processes using oxides as the starting materials. Conventional methods require a high calcination temperature, usually leading to inevitable particle coarsening and aggregation of the powders. The presence of hard particle agglomerates may result in poor microstructure and properties of the ceramics.
  • One technique to avoid such hard particle agglomerates is to use ultra-fine, calcined powders to fabricate ceramic components. These ultrafine powders can be synthesized by wet-chemistry-based processing routes (e.g., chemical co-precipitation, sol-gel process, and hydrothermal reaction).
  • wet-chemistry-based processes the precursor powders must be calcined at a temperature 500-900°C to get the designed crystallographic phase.
  • wet-chemistry-based methods usually involve chemicals that are sensitive to moisture or light, making them difficult to utilize, and may be very time consuming.
  • a particular advantage of wet-chemistry-based techniques is that the shrinkage variation between batches is more forgiving, meaning less geometrical anomalies arise.
  • a polymeric binder is introduced to enhance dispersion stability, and provide strength to the final coating.
  • the polymeric binder is dissolved in the solvent or suspended (in the form of an emulsion) and serves as "glue," which will tie the ceramic particles together in the dried film.
  • the powder is encased in the polymeric resin during the slip preparation, but the resulting green tape is a continuous phase resin that surrounds entrapped particles. As it is the only continuous phase in the green tape, the binder has the greatest effect on properties such as strength, flexibility, plasticity, ability to laminate, durability, toughness printability, smoothness, and dimensional stability.
  • these film formers are polyvinyls, celluloses, or polyacrylates. Factors that influence polymer selection may include solubility, viscosity, cost, strength, glass transition temperature, ability to modify glass transition temperature, decomposition temperature and kinetics, sintering atmosphere, and ash residue.
  • long chain alcohol e.g. 4 carbon atoms or higher in the chain
  • esters of acrylic or methacrylic acid yield virtually no ash upon decomposition, have fast burnout, and are often preferred for advanced electro-ceramic materials.
  • the polymer chain length of the binder may vary considerably. Generally, shorter chain polymers may be used to generate slips with higher ceramic loadings because they will display lower viscosities, and burnout faster at lower temperatures. A trade-off associated with lower molecular weight polymers is the shorter chains often generate weaker films, thus requiring a larger volumetric content. The larger volumetric content can make shrinkage control more difficult during burn-out and sintering, but can be repeatable through systematic process development.
  • the solvent will evaporate from the system, leaving void space behind. Some of the empty space will dissipate as the body contracts due to drying shrinkage, while the remaining space previously occupied by the solvent will generate porosity. Residual porosity contributes to further processing variables such as compressibility, strength, printability (ink adhesion), ability to laminate, and shrinkage.
  • the choice of solvent often depends on ability to wet the ceramic particles, compatibility with the selected binder, and ability to dry off in a controlled manner which does not lead to cracking, blistering, skinning, or excessive shrinking while drying.
  • solvents without hazardous air pollutants (“HAP”) and volatile organic compounds (“VOC”) are often preferred for volume manufacturing.
  • plasticizer is loosely used to describe any additive that imparts either flexibility or plasticity to the green tape, and could essentially be considered a very slow evaporating solvent.
  • a plasticizer may be used to increase the binder's flexibility, workability, and/or distensibility. The mechanism of action depends upon the type of plasticizer (type 1 or type 2). Plasticizers may provide the advantage of facilitating handling, punching, and shaping the green tape, but the disadvantage of diminished dimensional stability. The chemistry and quantity of plasticizer in the slurry formation may be optimized in such a manner that the tape can be processed in to the MLD without sacrificing control over the final device geometry.
  • a preferred method to maintain flexibility, and greatly extend shelf life of such thin layers of green tape is the use of binders with a low glass transition temperature (Tg).
  • Tg glass transition temperature
  • blending in a binder with a T g of 20°C or less will plasticize the primary binder, and provide smooth, uniform removal of organic material during binder burnout.
  • the slurry may be formulated in such a way that cast ceramic structures with the desired phase and physical characteristics are generated.
  • the structure should typically be dense, and designed in such a way that the shrinkage is well controlled and reproducible on a lot-to-lot basis.
  • a doctor blade machine may be used.
  • One illustrative example of such equipment is shown in FIG. 4.
  • Casting is accomplished by spreading the slurry formulation to form a paste on a moving carrier substrate and removing some of the volatiles.
  • the preferred viscosity profile for the mill base, or dispersion is Newtonian, or near Newtonian, as this is an indicator of good dispersion of the ceramic powder.
  • the final slurry used for doctor blading may be a non-Newtonian fluid containing a mixture of ceramic powder, solvent, and polymer resin, plasticizer, etc., which displays a shear- thinning, or pseudoplastic, viscosity profile.
  • Thixotropy is an undesirable quality for tape- casting where, when a significant shear is applied, viscosity decreases and when left to stand the viscosity will increase. In other words, when the slurry is drawn under the blade, the viscosity will decrease, and upon casting, the viscosity increases preventing unnecessary flow and distortion of the sheet. Since thixotropy shows unstable behavior (which will result in poor thickness control), the sheets should be dried quickly in order to retain their shape. It should be noted that as the slurry experiences more shear stress with greater shear rate, granular and aticular particles can become oriented. A consequence of the orientation is the shrinkage rates in the x and y direction may be different and this effect can be demonstrated to a greater extent in thinner sheets.
  • a thin, flexible tape that can be cut and stamped to any desired configuration prior to firing.
  • These green sheets comprise ceramic powder, binder (polymer materials, dispersing agents and plasticizers), and voids. It is desirable that the various ingredients are dispersed evenly and that the structure is homogeneous in the x, y, and z axes. From a macrostructure perspective, the thickness of the green sheet should be uniform (since the thickness of the green sheet will be the thickness of one layer in the MLD and this impacts the consistency of the end unit shape and performance).
  • the green sheet should display minimal anisotropy, and there should be no macro defects such as scratches, cracks, blisters, or pin holes.
  • the surface should have excellent smoothness, and it is desirable that there is no difference in the microstructure of the top and bottom of the sheet.
  • the green sheets When leaving the green sheets to stand and when storing them it is desirable for dimensional changes and changes in characteristics to be kept to a minimum. If the dimensions change after the electrode pattern is printed on the surface of the green sheet or after blanking or punching (each discussed further below), the green sheet will not match those above and below in the MLD resulting in defects and the like. In addition, the green sheet should have the mechanical strength (hardness and elongation) to withstand the handling involved in each process. If the green sheet is removed from the carrier, the sheet may stretch or even break in some cases. Additionally, the cutting and punching processes can cause open or short circuits due to the shape of the holes formed.
  • the surface of the sheet should show minimal surface roughness.
  • the conductive paste should have excellent adhesion to the sheet.
  • the solvent in the ink should have good compatibility with the green sheet, penetrating and being absorbed without dissolution of the tape binder or blurring of the pattern.
  • the sheets should have elasticity and thermoplasticity. However, while the layers should adhere together, it is desirable that they do not distort any more than necessary.
  • the presently disclosed green tape technology also allows the possibility of fabricating three-dimensional ("3D") structures using multiple layers of green tapes.
  • Each layer is fabricated in the green (before firing) with whatever features are needed for the overall function of the 3D structure.
  • Each layer may have specific geometries, vias, and internal electrical elements (e.g., electrodes).
  • the individual layers may be arranged (e.g., stacked) and placed in a registry to yield the desired structure.
  • the location holes for registry and the vias may be punched, although they can additionally or alternatively be chemically dissolved, etched, abraded, or cut, in other embodiments.
  • each of the green sheets may be punched, cut, and other machined to form a desired shape. Holes are often punched for alignment and via connections between layers. Punching and/or drilling may be used with numerical control ("NC"). Since there are hard ceramic particles mixed into the green sheets, abrasion of the tooling may occur readily, and wear charts should be utilized to maximize precision. Mechanical tooling can be applied to both via formation and shaping. As the green sheets are composed of ceramic particles and polymers, the shaping can additionally or alternatively occur through polymer degradation. By changing spot size and/or intensity of the laser, high precision x-y displacements and depth of penetration can be achieved.
  • green sheets having the shapes illustrated FIG. 5 can be fabricated (by way of example). These designs can be extrapolated to accommodate any number of devices in an array configuration.
  • the geometry of each cantilever can be identical (see middle diagram in FIG. 5) or can vary depending upon the application (see right diagram in FIG. 5). There is no fundamental limitation associated with the number of devices in an array configuration. Biosensors using an array of identical cantilevers can use one or more cantilevers as control groups.
  • Biosensors using an array of cantilevers of varying geometries may be beneficial for targeting detection of particulates with varying sizes (proteins, viruses, bacteria, spores, oocytes, etc) because each cantilever will have a linear range of operation. Smaller cantilever devices will respond in a linear fashion for smaller particles, while larger cantilevers will have a linear dose response curve for larger particles.
  • the configuration may include redundant shapes to serve as control/reference sensors.
  • the energy efficiency collected from external vibrations is dependent upon the applied frequency of the vibration and the resonant frequency of the energy harvester.
  • the device By building an array of identical geometries, the device would generate the maximum amount of electrical energy in response to a fixed stimulation vibration. This is preferred if the external vibration is fixed or known, such as in a pump or motor, as it can be used to maximize energy collection, and also serve as a sensor for monitoring device function. In other words, if the energy harvesting power output response begins to drift, it could indicate the device is vibrating at a different frequency due to malfunction, etc. Alternatively, if the environmental conditions will change, and the frequency of the applied vibrations can vary, it would be beneficial to use an array of cantilevers with varying resonant frequencies to ensure energy can be generated under a wider range of applications.
  • the method 300 may also utilize screen printing (sometimes also referred to as gap printing) for printing electrodes, wiring patterns, and via filling on the green sheets.
  • Screen printing is a technique in which a gap is set between the mask and the green sheet and, when a squeegee passes over the mask, the paste (or powder) is pushed through the opening in the mask onto the green sheet.
  • Proper performance of the electrodes, wiring, and/or vias will depend upon print quality, including accurate positioning of the pattern, appropriate transfer ratio, and proper transfer shape)with stable/repeatable wet and dry thicknesses. This print quality will be impacted by screen specifications, printing process conditions, paste characteristics, and green sheet characteristics.
  • the solution properties of the solvents in the paste should be considered so as to facilitate wetting, deter bleeding, and avoid damaging the underlying green sheet.
  • FIGS. 6 and 7 illustrate various embodiments of electrode patterns for MLDs.
  • the electrode patterns (cross hatched lines) on the punched green sheet can run all the way to the edge of the cantilevers for complete coverage or, in other embodiments, may stop short of the edge.
  • One advantage of using a pull- back is to prevent the paste from running over the edge and shorting the ceramic.
  • An additional advantage is the ability to confine the application of the external field which can be used to improve the quality factor of the resonator. Bonding pads can also be deposited to facilitate external electrical connections. Two patterns may be utilized to indicate the top and bottom electrodes.
  • the electrode patterns are differentiated to indicate that they will serve as opposing terminals (i.e., the top will be positive and the bottom will be negative, or the top can be negative and the bottom positive).
  • the vias can be printed with a paste as well to serve as electrical conducts.
  • the degree of filling can vary from a complete plug to coating a section of the walls. The degree of filling is dictated by sintering stresses and desired hermeticity.
  • the method 300 also involves laminating multiple green sheets to make a single substrate by aligning several layers of green tape on which the vias and printed circuit patterns have been formed.
  • Stacking is the process of layering the sheets of green tape
  • alignment is the process used to ensure that the circuit contacts in the three dimensional network make adequate connections. Alignment may be carried out using markers printed on the green tapes or holes punched in the green tape in conjunction with 4 CCD cameras and an x-y-angle stage.
  • Pressure and heat may be applied and the layers of green tape to ensure each sheet sufficiently bonds to the sheets above and/or below it.
  • Lamination can be carried out by stacking and aligning one sheet at a time, or multiple layers at one time. The pressure and heat can be applied using molds/fixtures with uniaxial and/or isostatic pressing. Care should be taken to ensure vertical splitting, surface blistering, stepped interlayer, circular, internal interlayer delamination do not occur during these processes.
  • Lamination may be used to build thickness for the MLD. However, lamination may also be used to control shrinkage, and minimize defects as the layers of tape can be rotated relative to one another as in building composites. Additionally, these techniques may be used to exploit the construction of a mechanical clamp. Using a higher modulus material such as a ceramic can improve the effect of the clamp.
  • FIG. 8 illustrates one embodiment of layer green sheets of the same or different composition to clamp the cantilever device (horizontal lines).
  • the additional tape can be punched with vias to provide electrical connection to the external circuit, and laminated to build sufficient thickness to serve as a mechanical clamp.
  • the 3D structure is ready for sintering (also sometimes referred to as firing or densification).
  • sintering also sometimes referred to as firing or densification.
  • the porous green body undergoes a high temperature heat treatment, where significant atomic diffusion happens to eliminate pores and vacancies.
  • the binder may be burnt out completely below a temperature of 500°C, leaving a porous body for final sintering.
  • the pores of a ceramic are usually closed, and the ceramic has
  • Ceramic powders can be fused and densified through a variety of sintering methodologies including heat, pressure, electromagnetic radiation (e.g., microwave, IR), electric currents, or a combination of those processes.
  • sintering methodologies including heat, pressure, electromagnetic radiation (e.g., microwave, IR), electric currents, or a combination of those processes.
  • Liquid phase, reactive (transient liquid, and/or solid state) sintering techniques in which the phase changes and chemical reactions between constituent phases take place during sintering process, may be utilized. Such techniques can be more advantageous than conventional calcination and sintering methods because of their simplified processing procedures and enhanced densification.
  • the densification mechanisms described above can be used to reduce the energy input requirements for sintering, which allows for better control of the stoichiometry and microstructure.
  • these techniques are capable of displaying repeatable shrinkage, and shrinkage rates, providing tight geometrical tolerances of the final sintered devices.
  • additional metallization can be applied for soldering or wire- bonding.
  • This additional metallization may facilitate the attachment of electrical connections of the device to the external electronics. Attachment of the device to external circuitry should be conducted in such a way that does not damage the device.
  • TEC mismatched thermal expansion coefficients
  • the microcracks caused by the thermal stresses may become nuclei for crack propagation, especially during operation in an electric field. Mismatched contraction during cooling can make the metallization in the tensile state and the ceramic layer in the compressive state. The mismatch may be amplified by the rapid cooling rate, as electric power of the furnace suddenly stops at high temperature.
  • the resultant shear stress at the interface may cause the formation of interfacial microdefects.
  • the mismatched TEC may still cause the production of interfacial cracks because of the reduced thermal relaxation effects compared to that under the condition of high temperature.
  • a small TEC difference between the metallization and the ceramic should be employed for high-reliability MLD.
  • the last step of the method 300 will be poling, in order to orient the ferroelectric domains.
  • Grains in ferroelectric ceramics and polycrystalline films always contain multiple domains. Each domain has its own polarization direction. If the polarization directions through the material are random or distributed in such a way that it leads to a zero net polarization, the pyroelectric and piezoelectric effects of individual domains will cancel and such material is neither pyroelectric nor piezoelectric.
  • Polycrystalline ferroelectric materials can be brought into a polar state by applying an adequate electric field. This process, which is referred to as poling, can reorient domains within individual grains in the direction of the field. The procedure for poling can vary depending upon the composition of the piezoelectric material, part design, and desired electrical properties. A poled polycrystalline ferroelectric exhibits pyroelectric and piezoelectric properties, even if many domain walls are still present.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Devices For Post-Treatments, Processing, Supply, Discharge, And Other Processes (AREA)

Abstract

La présente invention concerne des dispositifs multicouches (DMC) à échelle micrométrique et nanométrique et des procédés de fabrication desdits dispositifs. Selon un mode de réalisation donné à titre d'exemple, un procédé de fabrication d'un DMC peut comprendre le coulage en bande d'un coulis comprenant une poudre céramique et un liant en vue de former une pluralité de feuilles vertes, la formation d'une ou plusieurs feuilles de la pluralité de feuilles vertes dans une forme souhaitée, le dépôt d'un motif de circuit sur une ou plusieurs feuilles vertes de la pluralité de feuilles vertes, la stratification de la pluralité de feuilles vertes avec chaque feuille verte chevauchant au moins partiellement au moins une feuille verte adjacente, et la cocuisson de la pluralité de feuilles vertes stratifiées en vue de former le dispositif multicouche.
PCT/US2018/016029 2017-01-30 2018-01-30 Dispositifs multicouches et procédés de fabrication WO2018140972A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201762452335P 2017-01-30 2017-01-30
US62/452,335 2017-01-30

Publications (1)

Publication Number Publication Date
WO2018140972A1 true WO2018140972A1 (fr) 2018-08-02

Family

ID=62979636

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2018/016029 WO2018140972A1 (fr) 2017-01-30 2018-01-30 Dispositifs multicouches et procédés de fabrication

Country Status (1)

Country Link
WO (1) WO2018140972A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112408996A (zh) * 2020-12-07 2021-02-26 广西新未来信息产业股份有限公司 一种压敏电阻瓷片的烧结方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3838204A (en) * 1966-03-30 1974-09-24 Ibm Multilayer circuits
US5112653A (en) * 1989-07-03 1992-05-12 Consolidated Papers, Inc. Method of and apparatus for coating high speed traveling webs
EP0396806B1 (fr) * 1989-05-12 1994-02-02 Ibm Deutschland Gmbh Structure vitrocéramique et méthode pour la fabriquer
US5601672A (en) * 1994-11-01 1997-02-11 International Business Machines Corporation Method for making ceramic substrates from thin and thick ceramic greensheets
US20060114641A1 (en) * 2004-11-25 2006-06-01 Kyocera Corporation Multilayer ceramic capacitor and method for manufacturing the same
US20070289691A1 (en) * 2006-06-13 2007-12-20 Kim Yong S Method of manufacturing non-shrinkage ceramic substrate
US20090251869A1 (en) * 2008-04-02 2009-10-08 Hitachi Metals, Ltd. Multilayer ceramic substrate, electronic component, and method of manufacturing multilayer ceramic substrate
US20120019108A1 (en) * 2009-05-22 2012-01-26 Tdk Corporation Piezoelectric ceramic composition and piezoelectric element

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3838204A (en) * 1966-03-30 1974-09-24 Ibm Multilayer circuits
EP0396806B1 (fr) * 1989-05-12 1994-02-02 Ibm Deutschland Gmbh Structure vitrocéramique et méthode pour la fabriquer
US5112653A (en) * 1989-07-03 1992-05-12 Consolidated Papers, Inc. Method of and apparatus for coating high speed traveling webs
US5601672A (en) * 1994-11-01 1997-02-11 International Business Machines Corporation Method for making ceramic substrates from thin and thick ceramic greensheets
US20060114641A1 (en) * 2004-11-25 2006-06-01 Kyocera Corporation Multilayer ceramic capacitor and method for manufacturing the same
US20070289691A1 (en) * 2006-06-13 2007-12-20 Kim Yong S Method of manufacturing non-shrinkage ceramic substrate
US20090251869A1 (en) * 2008-04-02 2009-10-08 Hitachi Metals, Ltd. Multilayer ceramic substrate, electronic component, and method of manufacturing multilayer ceramic substrate
US20120019108A1 (en) * 2009-05-22 2012-01-26 Tdk Corporation Piezoelectric ceramic composition and piezoelectric element

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
EKLUND: "Hot and Cold Isostatic Pressing of Ceramics", CERAMIC INDUSTRY ADVANCED, 2 May 2016 (2016-05-02), pages 1 - 5, XP055524634 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112408996A (zh) * 2020-12-07 2021-02-26 广西新未来信息产业股份有限公司 一种压敏电阻瓷片的烧结方法

Similar Documents

Publication Publication Date Title
WO2005011009A1 (fr) Composant electronique du type stratifie, procede de production de celui-ci et element piezoelectrique du type stratifie
De Beauvoir et al. New opportunities in metallization integration in cofired electroceramic multilayers by the cold sintering process
Zhang et al. Sintering behavior, properties, and applications of co‐fired piezoelectric/low temperature co‐fired ceramic (PZT‐SKN/LTCC) multilayer ceramics
CN101217180A (zh) 一种无铅压电厚膜制备方法
Santawitee et al. Processing of printed piezoelectric microdisks: effect of PZT particle sizes and electrodes on electromechanical properties
JP7239350B2 (ja) 圧電セラミックス及びその製造方法、並びに圧電素子
Zheng et al. 3D printing orientation controlled PMN-PT piezoelectric ceramics
JP2010225705A (ja) 積層型圧電素子及びその製造方法
Liu et al. Effect of the slurry composition on the piezoelectric properties of PZT ceramics fabricated via materials extrusion 3D printing
WO2018140972A1 (fr) Dispositifs multicouches et procédés de fabrication
JP2008050206A (ja) 圧電材料およびその製造方法、並びに、圧電素子
KR940010095B1 (ko) 그린 세라믹체 소성시의 수축 감소 방법
Damamme et al. 3D printing of doped barium-titanate using robocasting-Toward new generation lead-free piezoceramic transducers
CN104926301A (zh) 压电器件
TWI356049B (en) Method for manufacturing ceramic compact
JP2014012620A (ja) 配向性セラミックの製造方法、及び配向性セラミック、並びにセラミック電子部品
JP4029408B2 (ja) 難焼結性拘束用グリーンシート及び多層セラミック基板の製造方法
JPH11354370A (ja) 積層セラミック電子部品
Panda et al. Tape Casting Technique for Fabrication of Piezoelectric Ceramics and Other Multilayered Devices-A Review
Medesi et al. A novel co-casting process for piezoelectric multilayer ceramics with silver inner electrodes
JP2004241590A (ja) 積層型圧電体素子
JP4868707B2 (ja) 積層型圧電素子および噴射装置
Torah Optimisation of the piezoelectric properties of thick-film piezoceramic devices
EP0993242A1 (fr) Procede servant a fabriquer un substrat en ceramique possedant des couches multiples
JP2008037675A (ja) 低温焼結セラミック組成物、セラミック基板およびその製造方法、ならびに電子部品

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18745032

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18745032

Country of ref document: EP

Kind code of ref document: A1