(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY(PCT)
`
`(19) World Intellectual Property Organization f
`International Bureau
`
`= ANDAA
`
`
`
`(43) International Publication Date
`28 August 2008 (28.08.2008)
`
`International Patent Classification:
`HOLL 23/34 (2006.01)
`
`(10) International Publication Number
`WO 2008/102266 A2
`
`(74)
`
`INFERMATA SYSTEMS
`Common Representative:
`LTD. Mishli, Oz, P.O.B. 13068, Kochay Yair, 44864
`Kochav Yair (IL).
`
`(51)
`
`(21)
`
`(22)
`
`International Application Number:
`PCT/TB2008/000830
`
`(81)
`
`International Filing Date:
`25 February 2008 (25.02.2008)
`
`Designated States (unless otherwise indicated, for every
`kind of national protection available): AE, AG, AL, AM,
`AO, AT, AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, CA,
`CH, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, EC, EE,
`EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID,
`IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, KZ, LA, LC,
`LK, LR, LS, LT, LU, LY, MA, MD, ME, MG, MK, MN,
`MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PG, PH,
`PL, PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, SV,
`SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN,
`ZA, ZM, ZW.
`
`(84)
`
`Designated States (unless otherwise indicated, for every
`kind of regional protection available): ARIPO (BW, GH,
`iM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM,
`ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM),
`European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI,
`FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, MC, MT, NL,
`NO, PL, PT, RO, SE. SI. SK, TR), OAPI (BF, BJ, CF, CG,
`CI, CM, GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG).
`Published:
`without international search report and to be republished
`uponreceipt of that report
`
`(25)
`
`Filing Language:
`
`(26)
`
`Publication Language:
`
`English
`
`English
`
`(30)
`
`(71)
`
`(72)
`(75)
`
`Priority Data:
`60/902,972
`60/972,657
`60/997,807
`
`23 February 2007 (23.02.2007)
`14 September 2007 (14.09.2007)
`5 October 2007 (05.10.2007)
`
`US
`US
`US
`
`Applicant (for all designated States except US): INFER-
`MATA SYSTEMS LTD. [IL/L]; 78 Ha‘ilanot Street,
`Kochav Yair (IL).
`
`Inventors; and
`Inventors/Applicants (for US only): BITON, Kfir
`{IL/IL]; 56 Belinson St., Halfa (IL). DOLLBERG, Yosh
`[IL/TLJ; 3 Hess St., Raanana(IL).
`
`
`
`008/102266A2IMNTININNININUNMINIONHHIATAA
`
`(54) Titles METHOD AND APPARATUS FOR RAPID FABRICATION OF FUNCTIONAL PRINTED CIRCUIT BOARD
`
`5108
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`
`
`Figure 5
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`570
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`540
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`400
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`It is intended that the systems
`(57) Abstract: Systems and methods are provided for producing functional printed circuit boards.
`@¥ and methods described herein will allow the production of functional PCBs in a more efficient and less labor- and equipment-inten-
`
`wo sive manner than may be obtained using conventional production methods. The produced functional PCB would have the required
`
`mechanical, thermal, electrical, etc., characteristics enabling it to function in a manner corresponding to a design characteristics of
`a conventional PCB.
`
`Shenzhen Tuozhu 1008
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`1
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`Shenzhen Tuozhu 1008
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`

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`WO 2008/102266
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`PCT/IB2008/000830
`
`METHOD AND APPARATUS FOR RAPID FABRICATION OF FUNCTIONAL
`
`PRINTED CIRCUIT BOARD
`
`CROSS-REFERENCE TO RELATED APPLICATIONS
`
`[0001]
`
`This Applicationis a continuation of and claimspriority from U.S. Application,
`
`Serial Number60/902,972, filed February 23, 2007; U.S. Application, Serial Number 60/972,657,
`
`filed September 14, 2007; and U.S. Application, Serial Number 60/997,807, filed October5,
`
`2007; the disclosureofall of which is incorporated herein by referencein its entirety.
`
`BACKGROUND
`
`1.
`
`Field of the Invention
`
`[0002]
`
`The generalfield of the invention relates to the field of the manufacture of printed
`
`circuit boards. More specifically, the present application relates to systems and methods for
`
`producing functional printed circuit boards, including functional prototype circuit boards, in a
`
`quick, safe, clean, waterless, efficient and compact manner.
`
`2.
`
`Related Arts
`
`[0003]
`
`Printed circuit boards (PCBs) are used to mechanically support and electrically
`
`connect electronic components using conductive pathways,or traces. In conventional PCB
`
`manufacture, such conductive pathwaysor traces are etched or milled from coppersheets
`
`laminated onto a non-conductive substrate. Such a processis relatively time consuming and
`
`utilizes harmful materials and solvents. Additionally, these processes generate waste material
`
`that needs to be disposed ofin a safe and environmentally sound manner. PCBs maybe used in
`
`any ofa variety of applications, including computers, cell phones, and otherelectronics
`
`applications.
`
`[0004]
`
`Oneissue associated with conventional PCB manufactureis that the production of
`
`the PCBsis a relatively complicated and time-consuming process. For example, to produce a
`
`single prototype PCB using conventional manufacturing methods, it may require, typically,
`
`]
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`between 5 and 30 working days (including electronic component assembly and shipmenttimes),
`
`mainly depending on complexity of the fabricated board. Additionally, because various stages of
`
`the production are typically performed usinga variety of different equipment, which may be
`
`located in different locations, the production of conventional PCBsrequirelogistical
`
`coordination which maylead to further delays. Consequently, conventional fabrication
`
`techniques introducesignificant time delays, especially in prototype fabrication and design of
`
`new devices utilizing PCBs.
`
`[0005]
`
`Anotherissue associated with conventional PCB manufacture is the intensive use
`
`of fabrication tools, such as masks and stencils throughout most process phases, thus requiring
`
`production of new tools and patterns for each design fabricated. Asthis is a fair overhead for
`
`mass production runs, small quantity production runs (such as New Product Introduction — NPI,
`
`and prototyping in particular) suffer enormous overhead of time, costs, handling and materials.
`
`The conventional use of masks also necessitates the use of hazardous materials and solvents,
`
`thereby requiring certain steps of the manufacturingto be carried out in specially designed
`
`facilities, which increase the manufacturing costs.
`
`[0006]
`
`Recent trends in the industry lead to higher complexity PCB fabrication due to
`
`use of more complex technologies and higher demandsin fabrication. Some examplesare:
`
`higher clock frequencies, higher demands on controlled impedance, miniaturization which
`
`derives requirements for smaller traces, smaller pads and vias diameter and more layers. The
`
`smaller the features are, the harder it will be for conventional technology to handle them due to
`
`fundamental limitations of the traditional fabrication process. For instance, registration (i.e.
`
`lamination of separate board layers) is a problematic phase in terms of accuracy, which is driving
`
`conventional PCB fabrication downin termsofyield and accuracy.
`
`[0007]
`
`The requirements on the registration betweenlayers oftraditional PCB
`
`manufacture increase with advanced technologies. Furthermore, registration is one ofthe
`
`bottlenecks in the process, requiring heavy and expensive equipment, and, most importantly, is a
`
`challenge in terms of accuracy and yield (as layers are fabricated individually, suffering
`
`individual, non-linear stretching, and then should be aligned and laminated in accuracies of tens
`
`of microns). Another bottleneck in conventional manufacturing processis the drilling. A typical
`
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`PCBcontains hundredsto tens of thousands holes in various diameters, which require a set of
`
`drilling machines (e.g. mechanical and laser drilling machines), working in sequential order
`
`possibly with every lamination of every new layerto form the different via types (e.g. buried via).
`
`It is a costly chain in the process, both in time and money(e.g., due to the rapid wear out of
`
`small-diameter drillers), and can cost up to 30%of overall fabrication costs.
`
`[0008]
`
`As is well known, conventional PCBs comprise conductive andinsulative layers
`
`formed over a substrate. The conductive layers form conductive circuitry according to the
`
`desired design. The conductive circuitry is fabricated using masks, e.g., photoresist masks, to
`
`delineate the designed conductive circuitry to be formed on the substrate. Once the mask has
`
`been developed, techniques such as metal electroplating are utilized to deposit conductive
`
`material, e.g., copper, onto the unmasked areas of the substrate. In some designs the maskis
`
`then removed, while in others the mask remains on the PCB. Electroplating or electroless
`
`plating is also used for the interconnect fabrication, to provide electrical connection between the
`
`metal layers. For further discussionrelating to this technology, specifically utilizing SU-8 as the
`
`resin for the photoresist, the readeris directed to U.S. patent 4,882,245, the content of which is
`
`incorporated herein by reference.
`
`[0009]
`
`SU-8 is an octafunctional epoxidized novolac commercially available from
`
`Celanese Corporation of Dallas, Texas. As explained in the above cited ‘245 patent, when
`
`properly mixed with a photoinitiator and other components, SU-8 may be cured using exposure
`
`to radiation, e.g., selective UV illumination, to thereby delineate the circuitry over the substrate.
`
`The ‘245 patent recommendsthe use of UVE 1014, available from General Electric, of Fairfield,
`
`CT,as the photoinitiator, but other materials, e.g., triarylsulfonium salts, may be used.
`
`[0010]
`
`Rapid prototyping is the automatic construction of physical objects or models
`
`using, e.g., solid freeform fabrication or direct writing. solid freeform fabrication (SFF) is a
`
`technique for manufacturing solid objects by the sequential delivery of energy and/or material to
`
`specified points in space to producethat solid. Rapid prototyping takes virtual designs from
`
`computer aided design (CAD) or animation modeling software, transforms them into thin,virtual,
`
`horizontal cross-sections and then creates each cross-section in physical space, one after the next
`
`until the modelis finished. With additive fabrication, the machine reads in data from a CAD
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`drawing and lays down successivelayers of liquid, powder, or sheet material, and in this way
`
`builds up the model fromaseries of cross sections. These layers, which correspondto the virtual
`
`cross section from the CAD model, are joined together or fused automatically to create the final
`
`shape. The primary advantage to additive fabricationis its ability to create rapidly almost any
`
`two or three-dimensional shape or geometric feature. Therefore, rapid prototyping is generally
`
`used to provide a physical model, but not necessarily a working model, of a designedpart.
`
`[0011]
`
`As PCBsare developed for a new product, it is commonto first design a PCB and
`
`then produce a prototype of the PCB, which requires considerable time, effort and expense. The
`
`PCBprototype is then assembled with electronic components and then tested. Mostoften, the
`
`test results reveal either functional or performancedeficiencies, so that the process is repeated
`
`until the last PCB prototype version is validated as correct and ready for mass production.
`
`[0012]
`
`Currently, the absolute majority of PCB prototypes are producedin the same
`
`process and equipment and are made of the same materials as mass production PCB. This
`
`manufacturing processis very labor intensive and inefficient for prototype and low-quantity
`
`production, resulting in considerable waste of time, efforts and expense.
`
`[0013]
`
`Therefore, there continues to be a long existing needin the life cycle of PCBs for
`
`the capability to rapidly and reliably move from the design stage through the prototype stage, to
`
`mass-production. Particularly, it is required to go directly from computer PCBdesigns to
`
`immediate prototypes economically and automatically.
`
`[0014]
`
`PCBprototypes are of very high importance in the PCB developmentprocess, as
`
`they constitute the ultimate means and measurefortesting the developed design, and are
`
`virtually the most important factor in taking the go-to-mass-production decision. Taking a risky
`
`go-to-mass-production decision which is based on PCBprototype whichis not correlated in
`
`testing results to the mass-production fabricated PCB mayresult in failure of mass-production
`
`series produced, thereby causing significant loss of time and money.
`
`[0015]
`
`Various technologies are currently used in the general art of rapid prototyping,
`
`including selective laser sintering (SLS), fused deposition modeling (FDM), stereolithography
`
`(SLA), laminated object manufacturing (LOM), electron beam melting (EBM), and 3D printing
`
`5
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`(3DP). In general, the art of rapid prototyping provides a physical, rather than functional,
`
`validation of the designed product.
`
`[0016]
`
`Several attempts have been previously madeto provide rapid PCB prototyping
`
`and manufacturing systems. Some of them also proposed that mechanical rapid prototyping or
`
`similar techniques may be used for PCB fabrication. For example,it has been proposedto utilize
`
`extrusion to form metal traces over conventional PCB substrate. According to another proposal,
`
`UV laseris used to partially cure a resin, so as to form a partially cross-linked substrate. Metal
`
`traces are then deposited over the substrate in a conventional manner. The substrate is then
`
`placed in a mold to changeits shape to a 3D shape, and is then completely cured to result in a 3D
`
`PCB. According to yet another proposal, 3D printing may be used for fabricating PCBs, using a
`
`printer head for dispensing conductive material and another printer head for dispensing insulative
`
`material. For further information about such techniques, the reader is directed to: WO0052976,
`
`US5,172,472, US5,099,090, US5,156,772, US6,169,605, US5,838,567, US5,264,061, and U.S.
`
`published application Nos. 2004/0077112.
`
`[0017]
`
`All of these attempts have indeed proposed alternative rapid methods for PCB
`
`production, compared to the conventional PCB manufacture method. Conventional PCB
`
`manufacturing processes, systems and materials were tightly adapted, for over 60 years, to the
`
`desired functionality of the produced PCB (which dependsonits use and target application).
`
`Therefore alternative manufacturing methods, which are different compared to conventional
`
`PCB manufacture methods, should be adapted to fit target PCB functionality criteria. Otherwise,
`
`the fabricated prototype PCB will be merely a mechanical, limited-functionality model, and not a
`
`fully functional electro-mechanical structure, as it is designated to be. To date, prior art attempts
`
`have failed to consider the functional value of the fabricated PCB, or provide meansto control
`
`the functionality and adaptit to desired functionality criterions.
`
`[0018]
`
`Generally, testing results depend on functional behavior of the PCB under
`
`different conditions. This behavior depends further on numerous properties, whicharestrictly
`
`defined in published PCB industry standards.
`
`[0019]
`
`Yet, in spite ofall efforts and available technology, rapid fabrication of PCB
`
`remains an elusive goal and to this day, PCB fabrication is made using decades-old techniques of
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`patterning, laminating, drilling conductorplating, solder resist, and screen printing. This
`
`protracted process causes delays and cost increases in both the design and manufacturing phases
`
`of any productutilizing a PCB. Accordingly, there is a need in the art for a revolutionary
`
`technology that would drastically reduce the fabrication time and manufacturing complexity.
`
`Additionally, there is a need in the art for a technique that would avoid or minimize the intensive
`
`use of toxic and/or hazardous materials of conventional fabrication methods. These methodsare
`
`also extremely wasteful, as it is estimated that only about 7%of the materials used in the
`
`production process end up in the PCB. The remaining 93% are mainly disposedoff as toxic
`
`waste, thereby causing significant environmental damage.
`
`SUMMARY
`
`[0020]
`
`The following summary ofthe inventionis described in order to provide a basic
`
`understanding of some aspects and features of the invention. This summary is not an extensive
`
`overview ofthe invention, and as suchit is not intended to particularly identify key orcritical
`
`elements of the invention, or to delineate the scope of the invention.
`
`Its sole purposeis to
`
`present some concepts of the invention in a simplified form as a prelude to the more detailed
`
`description that is presented below.
`
`[0021]
`
`According to an aspect ofthe present invention, methods and apparatus for the
`
`quick andefficient production of functional PCBs and functional PCBprototypes, directly from
`
`computer designs, are provided.
`
`[0022]
`
`A feature of the present invention is that the PCB fabricated, although produced
`
`of different materials and by different processes and machinery, compared to conventional
`
`manufacture methods (which are used in mass production), would yield testing results which
`
`highly correlate to the testing results of the same design when produced in conventional mass
`
`production methods.
`
`[0023]
`
`It is another aspect ofthe present invention that the method and apparatus
`
`provided herein produce PCBsin correlation to important properties and specifications defined
`
`in prominent industry standards, as will be described in detail in the description. Furthermore,
`
`the present invention includes predetermined means for complying with current and future
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`standardsin a structured manner, thus enabling flexibility in preparation to production of PCBs
`
`which comply with applicable industry standard, as specified for the required target application.
`
`[0024]
`
`According to the various exemplary embodiments described in the present
`
`application, systems and/or methods are provided for producing functional printed circuit boards.
`
`It is intended that the systems and methods described herein will allow the production of
`
`functional PCBsin a moreefficient and less labor- and equipment-intensive manner than may be
`
`obtained using conventional production methods. The produced functional PCB would have the
`
`required mechanical, thermal, electrical, etc., characteristics enabling it to function in a manner
`
`corresponding to design characteristics of a conventional PCB.
`
`[0025]
`
`The invented equipmentfor fabricating PCBsis “office friendly” and suitable for
`
`use in clean operations, such as research and developmentfacilities. Further, the systems and
`
`methodsfor fabricating the PCBs mayresult in the elimination (or tremendous reduction) of
`
`fabrication tools (e.g. masks and stencils) usage in this equipment, thus the fabrication processis
`
`easy to handle and very efficient for short production runs. Materials are selected for the various
`
`components of the PCBsthat possess suitable electronic, electrical, electromagnetic, thermal and
`
`mechanical characteristics, as will be described in greater detail below.
`
`[0026]
`
`According to an exemplary embodiment, rapid prototyping equipment is used to
`
`allow the production of functional PCBsin a shortened duration as compared to conventional
`
`methods(e.g., in as little as a several hours according to one exemplary embodiment). Such time
`
`savings may be achieved by changing not only the process phases involved in the manufacture of
`
`the PCBs, but also the equipment and materials used. Conventional PCB manufacturing requires
`
`tens to hundredsof skilled employees, very high investment in equipmentand inventory, and
`
`large manufacturing facility. On the other hand, according to a particular exemplary
`
`embodiment, a PCB may be manufactured by a single operator using a single system that
`
`integrates various components that previously were part of multiple different machines. The
`
`processis fully automated and the single employee is merely responsible for replacing cartridges,
`
`load the system with fabrication data, simple system calibration etc. Optionally, electronic
`
`component assemblyis integrated into the process so that a full turn-key system is provided.
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`[0027]
`
`Accordingto an aspect of the invention, a PCBis fabricated without the use of a
`
`substrate or the conventional copper clad laminate (CCL). Rather, additive technologies, such as
`
`SFF techniques and/or electronic printing techniques,are utilized to fabricate a PCB from scratch,
`
`i.c., without a starting substrate. In one specific example, a radiation-curable liquid composition
`
`is deposited onto a tray. Then, the radiation-curable liquid composition is radiated to delineate
`
`the shape and the boundaries of the PCB,so as to provide a cured insulating layer. That is, the
`
`radiation can be provided selectively so as to cure the liquid to any size and shape PCB,
`
`including geometric forms withinit (e.g. via holes). This first step generates an insulatorthatin
`
`essence replaces the conventional substrate that previously needed to be drilled and cut to the
`
`propersize and shape. After the insulating layer is cured, a conductive trace is deposited in an
`
`additive and maskless manneronthe curedinsulating layer using, e.g., ink jet, or other
`
`technology. Thereafter, another insulating layer is deposited using the radiation-curable liquid
`
`composition, and so on and so forth, until all of the layers are completed. Via metallization is
`
`also performed using additive technology, such as SFF. The PCB maythen beflipped and
`
`another sequenceofinsulation and conductive layers provided on the other side, so as to generate
`
`a multi-layer, double-sided PCB. Various curing and baking steps maybe utilized during the
`
`fabrication of each conductive and/orinsulative layer. Amongits various advantages,the
`
`inventive method avoids the problemsof alignment and registration by performing registration
`
`for each layer while it is being fabricated, hence avoiding accumulation of inaccuracies.
`
`[0028]
`
`According to an aspect of the invention, a method for fabricating at least one
`
`functional printed circuit board (PCB) is provided, comprising, a. obtaining a PCB fabrication
`
`data file; b. performing data conversion to generate a modified fabricationfile corresponding to
`
`the fabrication data file; c. performing data transformation by modifying parameters specified in
`
`the modified fabrication file to account for variation in materials and processes utilized for
`
`fabricating the PCB,the data transformation generating a transformed fabricationfile; d.
`
`providing a tray; e. using the transformed fabricationfile to fabricate a dielectric layer by:i.
`
`depositing into the tray a liquid composition;ii. allowing the liquid composition to spread over
`
`the surface of the tray; and, iii. curing selected areas of the liquid composition to delineate the
`
`shape and the boundaries of the PCB to provide a cured insulating layer having a top and bottom
`
`surfaces; and, f. using the transformedfabrication file to fabricate a conductive layer by
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`depositing a conductive trace on at least one of the top and bottom surfaces of the cured
`
`insulating layer; to thereby provide a PCB having performancecharacteristics correlating to
`
`performance characteristics of a conventionally fabricated PCB usingthe fabrication data file.
`
`The method mayfurther comprise repeating steps e and fa plurality of times over one of the top
`
`and bottom surfaces of the dielectric layer so as to provide a multi-layer one-sided PCB. The
`
`method may further comprise flipping the one-sided PCBsothat the cured insulating layer
`
`becomestop layer on the tray, and repeating steps e and fa plurality of times on the otherofthe
`
`top and bottom surfaces of the dielectric layer so as to provide a multi-layered double-sided PCB.
`
`The method may further comprise repeating steps e and fa plurality of times over both of the top
`
`and bottom surfaces ofthe dielectric layer to provide a multi-layered double-sided PCB. The
`
`method mayfurther comprise depositing one or more of an insulative solder mask layer, a
`
`conductive pad coating and a legend on the double-sided PCBusing colored dielectric material.
`
`[0029]
`
`Curing selected areas may compriseirradiating selected areas.
`
`Irradiating
`
`selected area may comprise directing UV radiation onto selected areas. Curing selected areas
`
`may further comprise a curing enhancementstep following the irradiating the selected areas.
`
`The curing enhancement step may comprise a heating step. The heating step may comprise
`
`radiating the fabricated PCB with microwaveradiation. In the method, step d may further
`
`comprise providing a release agent over the tray. Providing a release agent may comprise one
`
`of: providing a fabric layer overthe tray or spreadinga liquid releasing agent overthe tray. The
`
`method may further comprise fabricating holes in the cured insulation layer by defining non-
`
`irradiated areas and cleaning the non-radiated areas after the curing step. The method may
`
`further comprise depositing conductive substance into selected holes to thereby fabricate
`
`conductive vias. Step e may comprise depositing into the tray a liquid composition comprising
`
`an octafunctional epoxidized novolac and photoinitiator. The liquid composition may further
`
`comprise nano-particles. Depositing a conductive trace may comprise using a deposition head to
`
`inject conductive substance onto the cured insulating layer. Each time step e is performed, sub-
`
`steps 1. 11. and ili. may be repeated a plurality oftimes so as to fabricate the dielectric layer by
`
`fabricating a plurality of sub-layers. After each repetition of sub-step iii. heat may be applied to
`
`the fabricated PCB. Each time sub-stepsi. ii. and iii. are performed, the method may further
`
`comprise fabricating holes in the sub-layer. Each time sub-stepsi. ii. and iii. are performed, the
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`method may further comprise depositing conductive substance into selected holes. After a
`
`sequence of sub-stepsi. il. and lil. is performeda plurality of times, the method may further
`
`comprise depositing conductive substance into selected holes. At selected times wherein step e
`
`is performed, the method may further comprise fabricating curing enhancing tunnels in the
`
`fabricated dielectric layer. At selected times wherein step e is performed, the method may
`
`further comprise depositing soluble material to define voids in the fabricated dielectric layer.
`
`Eachtimestep e is performed, sub-stepsi. ii. and iii. may be repeated a plurality of times using
`
`at least two different dielectric materials, so as to fabricate the dielectric layer by fabricating a
`
`plurality of sub-layers having different dielectric insulation properties.
`
`[0030]
`
`In the method, step e may further comprise mixing into the dielectric materials at
`
`least one of ingredients that assist in conductors adherence, ingredients that mechanically
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`stabilize the dielectric material, and ingredients that thermally stabilize the dielectric and
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`material. Step e may further comprise mixing into the dielectric materials ingredients that
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`modify the insulating properties of the dielectric material. Step e may further comprise
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`depositing onto the dielectric layer an intermediate layer formed for improved conductive
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`material adherence to the dielectric layer. At selected times wherein step e is performed, the
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`method may further comprise generating trenches on at least one surface of the dielectric layer
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`and wherein step f comprises depositingat least part of the conductive trace into the channels.
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`Atselected times wherein step f is performed, the method may comprise depositing conductive
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`traces of varying thickness as specified by the transformed fabrication file. At selected times
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`wherein step f is performed, depositing conductive traces may comprise depositing a seed layer
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`of conductive material and forming a main conductive layer over the seed layer. Forming a main
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`conductive layer may comprise using electroplating. At selected times wherein step f is
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`performed, the method may further comprise performing and least one of automated optical
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`inspection of the formed conductive traces and electrical resistivity testing of the conductive
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`traces.
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`[0031]
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`The method may further comprise performingelectrical testing at completion of
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`fabrication of the PCB. A plurality of PCB boards may befabricated concurrently within the
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`tray. Each of steps e and f may further comprise selecting fabrication parameters accordingto at
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`least the desired insulation properties of the dielectric layer and resistivity properties of the
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`conductive layer. Step e,ii, may further comprise planarizing a top surface ofthe liquid.
`
`[0032]
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`According to an aspect of the invention, a method for fabricating at least one
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`functional printed circuit board (PCB)is provided, comprising: uploading PCB fabrication data
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`file onto a controller; utilizing the controller to control operation of a central handling station to
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`load and unload a fabrication tray onto and from a plurality of tray positioning stations; utilizing
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`the controller to control operation of a dielectric dispenserto dispense a dielectric substance onto
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`the tray and to control operation of a curing mechanism to cure the dielectric substance to form a
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`dielectric layer; utilizing the controller to control operation of a conductor dispenser to dispense
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`a conductive substance onto the dielectric layer; and, utilizing the controller to control operation
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`of a thermal station to thermally process at least one of the dielectric substance and the
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`conductive substance. Thermally processing may comprise exposingat least one of the dielectric
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`substance and the conductive substanceto at least one of: UV radiation, microwaveradiation,
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`and heater radiation. Controlling operation ofthe dielectric dispenser may comprise operating a
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`liquid dispenser to dispensea radiation curable liquid onto the tray, and wherein curing the
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`dielectric substance comprisesradiating the liquid. Control operation of a dielectric dispenser
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`may comprise operating a dispenser head to deposit dielectric substance according to layout
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`design of the dielectric layer. The method may further compriseutilizing the controllerto
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`control operation of a planarizing mechanism to planarize the dielectric layer. Controlling
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`operation of the conductor dispenser may comprise operating a printer jet to dispense conductive
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`trace material.
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`[0033]
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`The method may further comprise utilizing the controller to control operation of a
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`flipping mechanismto flip a fabricated board so as to form conductive traces on both sides of the
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`board. The method may further comprise fusing at least two fabricated boards together. The
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`method may further comprise: operating the control console to generate a freeform fabrication
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`file using at least the PCB fabrication data file; and, operating the control console to transform
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`the freeform fabricationfile into a transformed fabrication file, wherein selected data of the
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`freeform fabrication file is transformed so as to enable correlating performance characteristics of
`
`the PCB to performance characteristics of a conventionally fabricated PCB. Transforming into
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`transformed fabrication file may further comprise generating files to control the curing
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`mechanism to delineate vias. Transforming into transformed fabrication file may further
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`comprise generating files to control the curing mechanism to delineate vias having oblique, non-
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`vertical sidewalls. Transforming into transformed fabrication file may further comprise
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`generating files to fabricate mating structures on each fabricated board to ensure alignment
`
`during the step of fusing the fabricated boards.
`
`[0034]
`
`In the method,utilizing the controller to control operation of a conductor
`
`dispenser may comprise depositing conductive substance on both sides of the dielectric layer.
`
`The method may further comprise setting parameters of the curing mechanism to facilitate
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`fabricating dielectric layer having properties corresponding to conventional PCB insulation layer
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`fabricated according to the fabrication data file. The method may further comprisesetting
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`parameters of the conductor dispenser and the thermal station to facilitate fabricating conductive
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`layer having properties corresponding to conventional PCB conductive traces fabricated
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`accordingto the fabrication data file. Transforming into transformed fabricationfile may further
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`comprise changing a designed thickness of conducti