GB2196184A - Process for production of multilayer electrical device - Google Patents

Process for production of multilayer electrical device Download PDF

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Publication number
GB2196184A
GB2196184A GB8624309A GB8624309A GB2196184A GB 2196184 A GB2196184 A GB 2196184A GB 8624309 A GB8624309 A GB 8624309A GB 8624309 A GB8624309 A GB 8624309A GB 2196184 A GB2196184 A GB 2196184A
Authority
GB
United Kingdom
Prior art keywords
layer
tracks
apertures
process according
dielectric material
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
GB8624309A
Other versions
GB8624309D0 (en
Inventor
Peter Linley Kirby
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Crystalate Electronics Ltd
Original Assignee
Crystalate Electronics Ltd
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 Crystalate Electronics Ltd filed Critical Crystalate Electronics Ltd
Priority to GB8624309A priority Critical patent/GB2196184A/en
Publication of GB8624309D0 publication Critical patent/GB8624309D0/en
Publication of GB2196184A publication Critical patent/GB2196184A/en
Withdrawn legal-status Critical Current

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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0286—Programmable, customizable or modifiable circuits
    • H05K1/0287—Programmable, customizable or modifiable circuits having an universal lay-out, e.g. pad or land grid patterns or mesh patterns
    • H05K1/0289—Programmable, customizable or modifiable circuits having an universal lay-out, e.g. pad or land grid patterns or mesh patterns having a matrix lay-out, i.e. having selectively interconnectable sets of X-conductors and Y-conductors in different planes
    • 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
    • H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
    • H05K3/4038—Through-connections; Vertical interconnect access [VIA] connections
    • H05K3/4053—Through-connections; Vertical interconnect access [VIA] connections by thick-film techniques
    • H05K3/4061—Through-connections; Vertical interconnect access [VIA] connections by thick-film techniques for via connections in inorganic insulating substrates
    • 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
    • H05K3/4644—Manufacturing multilayer circuits by building the multilayer layer by layer, i.e. build-up multilayer circuits
    • H05K3/4664—Adding a circuit layer by thick film methods, e.g. printing techniques or by other techniques for making conductive patterns by using pastes, inks or powders
    • H05K3/4667—Adding a circuit layer by thick film methods, e.g. printing techniques or by other techniques for making conductive patterns by using pastes, inks or powders characterized by using an inorganic intermediate insulating layer
    • 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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0266—Marks, test patterns or identification means
    • 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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0286—Programmable, customizable or modifiable circuits
    • H05K1/029—Programmable, customizable or modifiable circuits having a programmable lay-out, i.e. adapted for choosing between a few possibilities
    • 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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/03—Use of materials for the substrate
    • H05K1/0306—Inorganic insulating substrates, e.g. ceramic, glass
    • 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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/09—Use of materials for the conductive, e.g. metallic pattern
    • H05K1/092—Dispersed materials, e.g. conductive pastes or inks
    • 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
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/09—Use of materials for the conductive, e.g. metallic pattern
    • H05K1/092—Dispersed materials, e.g. conductive pastes or inks
    • H05K1/095—Dispersed materials, e.g. conductive pastes or inks for polymer thick films, i.e. having a permanent organic polymeric binder

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacturing Of Printed Wiring (AREA)
  • Production Of Multi-Layered Print Wiring Board (AREA)

Abstract

A process for the production of a multilayer electrical device, particularly a programmed matrix device in which an identity code is permanently stored during manufacture, comprises: forming a first layer comprising conductive tracks (1) on an insulating substrate (2); forming a dielectric second layer (3) over the first layer, the second layer (3) having a pattern of apertures (5) through it accessing tracks (1) of the first layer; applying dielectric material to close one or more of the apertures (5) to leave one or more selected apertures remaining; and forming a third layer comprising conductive tracks (7) overlying the second layer (3) such that track material of the third layer passes through the one or more selected apertures in the second layer (3) to effect selected interconnection of tracks of the first and third layers. The selected interconnection of the tracks is used to define a selected code or bit pattern when the device is a programmed matrix device. The tracks are made of cermet materials or palladium-silver and the dielectric layer comprises glass or glass ceramic. <IMAGE>

Description

SPECIFICATION Process for production of multilayer electrical device This invention relates to a process for making a multilayer electrical device of the type in which one or more first electrically conductive coplanar tracks, supported and arranged on a substrate, is or are traversed by one or more second electrically conductive tracks such that one or more first tracks are electrically connected to one or more selected second tracks at chosen regions of traversal, through one or more apertures in a dielectric layer provided between the first and second tracks, while being electrically insulated by the dielectric layer from the other second tracks.The invention is particularly, but not exclusively, applicable to multilayer electrical devices in the form of programmed matrix devices which function as memory devices and large numbers can be manufactured each with a different, unique identity code permanently stored therein which is determined by appropriate choice of a pattern of interconnecting links formed between the first and second conductive tracks, at regions of their traversal, during the manufacturing process. Appropriate interrogating circuits are arranged to address the matrix device via the first and second conductive tracks and read the code stored in the device. Matrix devices of this nature can be incorporated in transponders for use in identification systems, the transponders being suitably embodied in the form of tags for attachment to animals, persons or objects to be identified.Remote interrogation systems can be provided to communicate with the transponders by a suitable means such as inductive loop, infra-red or radio-frequency transmission.
A matrix device of this type and a process for its manufacture is described in published British patent Application number GB 2167621A. In the process described in that Application, a plurality of parallel first conductive tracks is provided by screen printing, on an- insulating substrate. A film of a dielectric material is likewise provided over the first conductive tracks and a programmed laser is then used to form apertures through the dielectric at selected locations to expose certain underlying first conductive tracks.
One or more second conductive tracks is or are screen printed over the dielectric film to traverse the first conductive tracks and make electrical contact with selected first tracks through the apertures provided by the laser in the dielectric film. The device is therefore programmed during manufacture according to the pattern of apertures produced in the dielectric film. This is a very advantageous process since it allows a very large number of devices, each with its own unique code, to be readily produced by simple programming of the laser.
It also enables information relating to the codes to be stored in the laser programmer so that replacement devices of any particular code can be readily produced.
There are, however, requirements for producing programmed matrix devices without involving expensive and sophisticated laser equipment, particularly where a relatively small number of coded devices is required. It is an object of the present invention to provide a process for making a multilayer electrical device which does not require the use of a laser.
The present invention provides a process for the production of a multilayer electrical device comprising: providing an electrically insulating substrate; forming on a major face of said substrate a first layer comprising one or more electrically conductive film tracks; forming a second layer which is a film of dielectric material overlying the first layer, the second layer having a predetermined pattern of apertures through it accessing the one or more tracks of the first layer; applying dielectric material to close one or more apertures in the second layer such that one or more selected apertures remain accessing the one or more tracks of the first layer; and forming a third layer comprising one or more electrically conductive film tracks overlying the second layer such that film track material of the third layer passes through the one or more selected apertures in the second layer to make electrical contact with the one or more accessed tracks of the first layer to interconnect tracks of the first and third layers.
The pattern of apertures in the second layer is suitably such that any required pattern of electrical interconnection between tracks of the first and third layers can be selected during manufacture by appropriate application of dielectric material to those apertures which are not required for enabling the electrical interconnection to be effected.
Preferably the electrically conductive film tracks and the film of dielectric material comprise thick film materials and are produced by screen printing, the dielectric material being screen printed to directly form the said second layer with the predetermined pattern of apertures through it.
The electrically conductive film tracks may conveniently comprise cermet materials which are applied as an ink or paste by screen printing, and then fired. The dielectric material conveniently comprises a glass or glass-ceramic material which is also applied as an ink or paste by screen printing, and then fired.
Alternatively, the electrically conductive film tracks and the dielectric material may com prise conductive and dielectric polymer materials respectively which are applied as inks or pastes -by screen printing, and then heated to effect polymerisation or curing thereof.
As a further alternative, a combination of cermet materials and conductive polymer materials may be used for the conductive film tracks, with the dielectric material being either a polymer material or a glass or glass-ceramic material.
Application of dielectric material to close the one or more apertures in the second layer may be effected by manual or mechanical means. For example, dielectric ink or paste may be applied to the apertures by means of a small brush or a syringe.
In a particular embodiment, the multilayer electrical device comprises a programmed matrix device in which the one or more electrically conductive film tracks of the third layer are arranged in a direction non-parallel to the one or more tracks of the first layer and the film track material of the third layer passes through the one or more selected apertures in the second layer to interconnect tracks of the first and third layers and define a selected code or bit pattern.
The pattern of apertures in the second layer is suitably such that any required code or bit pattern can be selected during manufacture by appropriate application of dielectric material to those apertures which are not required for enabling the electrical interconnection to be effected between tracks of the first and third layers.
The invention is now described by way of example with reference to the accompanying drawing which represents an exploded perspective view of an embodiment of a programmed matrix device produced according to the process of the invention.
A first layer comprising a plurality of first electrically conductive film tracks 1 is screen printed onto a major face of an alumina ceramic substrate 2. The tracks 1 are arranged substantially parallel with one another. An example of a suitable material for the tracks 1 is palladium-silver (e.g. type 9308 material supplied by E I Du pont de Nemours & Co) which, after application by screen printing, is fired at a high temperature in well-known manner. A second layer 3 comprising a dielectric material, such as Du pont type 5704 material, is screen printed onto the substrate 2, on top of the tracks 1 using a printing screen arranged such that a predetermined pattern of apertures 5 is formed in the layer 3 during the printing operation. These apertures 5 are positioned in rows such that they overlie and access the first electrically conductive film tracks 1.It is required to provide a third layer comprising one or more second electrically conductive film tracks 7 overlying the dielectric layer 3 and traversing the first conductive tracks 1 and such that one or more of the second electrically conductive tracks 7 is or are electrically connected to certain selected first conductive tracks 1, through certain selected apertures in the dielectric layer 3. The selected interconnection of the first and second conductive tracks serves to programme the matrix device with a particular permanent binary or hexadecimal code during manufacture. Accordingly, to produce a range of devices each with a different code permanently programmed into it during manufacture it is necessary to arrange for different combinations of first and second tracks 1 and 7 to be interconnected during manufacture.This is achieved as follows in the process of the present invention. Before the second conductive tracks 7 are provided by screen printing on top of the dielectric layer 3 and preferably before firing the dielectric layer at high temperature in well-known manner, certain of the apertures 5 in the dielectric layer 3 are closed by application thereto of further dielectric material in the form of a paste or ink. A small brush or syringe may be used for this purpose, although other techniques may be envisaged. Selected apertures are allowed to remain open in the dielectric layer 3, these being identified by the dotted lines 9, and will ultimately be used for providing the desired interconnections between certain of the first and second conductive tracks 1 and 7 to define the unique programmed code for that specific matrix device.To produce devices with different codes, different combinations of apertures are closed in the dielectric layer 3 and others left open, but one standard screenprinted apertured dielectric layer 3 can be used as the basis for all required coded devices. After the selected apertures have been closed in the dielectric layer 3 the dielectric layer is fired at the temperature recommended for the material. The second conductive tracks 7, suitably comprising material of the same composition as used for the first conductive tracks 1, are then screen printed and fired on top of the dielectric layer 3 such that, for one or more of the tracks 7, material of these tracks enters the open apertures in the dielectric layer and contacts the portions 6 of the underlying first tracks 1. The programmed matrix device is thereby completed. Terminal regions 4 and 8 on the first and second tracks 1 and 7 respectively are used to connect the device with appropriate external circuitry, the terminal regions 4 being arranged to be uncovered by dielectric layer 3.
It is not essential that closure of the selected apertures in the dielectric layer 3 should be effected using the same dielectric material as that of the layer 3. A different material may be used for this purpose if desired. The dielectric layer 3 may also be fired before the apertures are closed, if desired, and a further firing operation carried out if necessary after applying the material to the apertures.
Although in the accompanying drawing the first and third layers are shown to each comprise a plurality of first and second tracks 1 and 7, if required only a single track could be provided for either the first or the third layer and a plurality of tracks provided for the other. This arrangement could be used to provide a programmed matrix device which functions as a pre-programmed bit set or binary coded array. If required also, electrical resistors, preferably of film form may be provided connected to the first or second conductive tracks 1 or 7. Such resistors can operate in well-known manner as pull-up resistors to maintain a steady state electrical condition on the conductive tracks with which they are associated.
The programmed matrix device produced by the present invention operates in the same way as the device described in Applicants' published patent Application No GB 2167621A and finds similar applications.

Claims (13)

1. A process for the production of a multilayer electrical device comprising: providing an electrically insulating substrate; forming on a major face of said substrate a first layer com prising one or more electrically conductive film tracks; forming a second layer which is a film of dielectric material overlying the first layer, the second layer having a predetermined pattern of apertures through it accessing the one or more tracks of the first layer; applying die lectric material to close one or more apertures in the second layer such that one or more selected apertures remain accessing the one or more tracks of the first layer; and forming a third layer comprising one or more electrically conductive film tracks overlying the second layer such that film track material of the third layer passes through the one or more selected apertures in the second layer to make electrical contact with the one or more accessed tracks of the first layer to intercon nect tracks of the first and third layers.
2. A process according to Claim 1 in which the pattern of apertures in the second layer is such that any required pattern of electrical interconnection between tracks of the first and third layers can be selected during manufacture by appropriate application of dielectric material to those apertures which are not re quired for enabling the electrical interconnection to be effected.
3. A process according to Claim 1, or 2, in which the electrically conductive film tracks and the film of dielectric material comprise thick film materials and are produced by screen printing, the dielectric material being screen printed to directly form the said second layer with the predetermined pattern of apertures through it.
4. A process according to Claim 1, 2 or 3, in which the electrically conductive film tracks comprise cermet materials which are applied as-an ink or paste by screen printing, and then fired.
5. A process according the any preceding Claim in which the dielectric material comprises a glass or glass-ceramic material which is applied as an ink or paste by screen printing, and then fired.
6. A process according to Claim 1, 2, or 3 in which the electrically conductive film tracks and the dielectric material comprise conductive and dielectric polymer materials respectively which are applied as inks or pastes by screen printing, and then heated to effect polymerisation or curing thereof.
7. A process according to Claim 1, 2, or 3 in which a combination of cermet materials and conductive polymer materials is used for the conductive film tracks, with the dielectric material being either a polymer material or a glass or glass-ceramic material.
8. A process according to any preceding Claim in which application of dielectric material to close the one or more apertures in the second layer is effected by manual or mechanical means.
9. A process according to Claim 8 in which dielectric ink or paste is applied to the apertures by means of a small brush or a syringe.
10. A process according to any preceding Claim in which the multilayer electrical device comprises a programmed matrix device in which the one or more electrically conductive film tracks of the third layer are arranged in a direction non-parallel to the one or more tracks of the first layer and the film track material of the third layer passes through the one or more selected apertures in the second layer to interconnect tracks of the first and third layers and define a selected code or bit pattern.
11. A process according to Claim 10 in which the pattern of apertures in the second layer is such that any required code or bit pattern can be selected during manufacture by appropriate application of dielectric material to those apertures which are not required for enabling the electrical interconnection to be effected between tracks of the first and third layers.
12. A process for the production of a multilayer electrical device substantially as hereinbefore described with reference to the accompanying drawing.
13. A multilayer electrical device whenever produced by the process of any preceding Claim.
GB8624309A 1986-10-10 1986-10-10 Process for production of multilayer electrical device Withdrawn GB2196184A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8624309A GB2196184A (en) 1986-10-10 1986-10-10 Process for production of multilayer electrical device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8624309A GB2196184A (en) 1986-10-10 1986-10-10 Process for production of multilayer electrical device

Publications (2)

Publication Number Publication Date
GB8624309D0 GB8624309D0 (en) 1986-11-12
GB2196184A true GB2196184A (en) 1988-04-20

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB8624309A Withdrawn GB2196184A (en) 1986-10-10 1986-10-10 Process for production of multilayer electrical device

Country Status (1)

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GB (1) GB2196184A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6622921B2 (en) * 1998-06-23 2003-09-23 Meto International Gmbh Identification element
WO2010042965A1 (en) 2008-10-17 2010-04-22 At & S Austria Technologie & Systemtechnik Aktiengesellschaft Marker for marking or coding an object and method for producing such a marker and use
WO2019185000A1 (en) * 2018-03-28 2019-10-03 奥特斯(中国)有限公司 Traceability of subsequent layer structure manufacturing of main body for component carriers by means of laterally and vertically displaced information carrying structures

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6622921B2 (en) * 1998-06-23 2003-09-23 Meto International Gmbh Identification element
WO2010042965A1 (en) 2008-10-17 2010-04-22 At & S Austria Technologie & Systemtechnik Aktiengesellschaft Marker for marking or coding an object and method for producing such a marker and use
CN102187744B (en) * 2008-10-17 2013-10-02 At&S奥地利科技及系统技术股份公司 Marker for marking or coding an object and method for producing such marker and use
DE202009018996U1 (en) 2008-10-17 2015-04-01 At & S Austria Technologie & Systemtechnik Aktiengesellschaft Mark for marking or coding an object
WO2019185000A1 (en) * 2018-03-28 2019-10-03 奥特斯(中国)有限公司 Traceability of subsequent layer structure manufacturing of main body for component carriers by means of laterally and vertically displaced information carrying structures
US11937369B2 (en) 2018-03-28 2024-03-19 AT&S(China) Co. Ltd. Traceability of subsequent layer structure manufacturing of main body for component carriers by means of laterally and vertically displaced information carrying structures

Also Published As

Publication number Publication date
GB8624309D0 (en) 1986-11-12

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