Showing papers on "Flexible electronics published in 1990"
Patent•
03 Apr 1990TL;DR: A multi-layer interconnect structure of alternating dielectric (e.g., polyimide) and metal is built on a substrate supporting a continuous layer of metal as mentioned in this paper, which is used as an electrode for plating vias.
Abstract: A multi-layer interconnect structure of alternating dielectric (e.g., polyimide) and metal (e.g., copper) is built on a substrate supporting a continuous layer of metal. This metal layer is used as an electrode for plating vias through all the dielectric layers. Once the desired number of layers are formed, the substrate is removed and the continuous metal layer is patterned. Solid metal vias having nearly vertical side walls can be stacked vertically, producing good electrical and thermal transfer paths and permitting small, closely-spaced conductors. Further, by mixing geometrical shapes of conductors, a variety of useful structures can be achieved, such as controlled impedance transmission lines and multiconductor TAB tape with interconnects on tape of different dimensions than TAB fingers.
204 citations
Patent•
31 Dec 1990
TL;DR: In this paper, a flexible, tear-resistant printed circuit comprising first and second electrical conductors and a flexible insulating core separating and supporting them is presented, and the core preferably comprises aromatic polyamide fiber in a resin binder matrix.
Abstract: The present invention provides flexible, tear-resistant printed circuits comprising first and second electrical conductors and a flexible, insulating core separating and supporting said first and second conductors. The core preferably comprises aromatic polyamide fiber in a resin binder matrix. Rigid/flex circuits including the flexible, tear-resistant printed circuits are disclosed.
95 citations
Patent•
30 Aug 1990TL;DR: In this paper, the inactive sides of integrated circuit chips are held in compression against a heat spreader by an elastomer pressed there against by a multilayer flexible printed circuit board.
Abstract: An electronic packaging module in which the inactive sides of integrated circuit chips are held in compression against a heat spreader by an elastomer pressed thereagainst by a multilayer flexible printed circuit board. A TAB frame, which may be demountable, interconnects integrated circuit chips to a multilayer flexible printed circuit board. A backing plate is fastened to a heat spreader so that it presses against the multilayer flexible printed circuit board. Contacts are compressed against the motherboard to interconnect the multilayer flexible printed circuit board thereto. Coaxial power connectors provide power and ground connections between non-peripheral portions of the multilayer flexible printed circuit board and the motherboard.
52 citations
Patent•
IBM1
TL;DR: In this paper, a flexible electrical assembly comprising a TAB device mounted on one surface of a flexible printed circuit board, a heat sink with a set of crimping members thereon mounted on an opposite surface of the board and a protective cover with attachment holes therein positioned above the TAB was described.
Abstract: Described is a flexible electrical assembly comprising a TAB device mounted on one surface of a flexible printed circuit board, a heat sink with a set of crimping members thereon mounted on an opposite surface of the printed circuit board and a protective cover with attachment holes therein positioned above the TAB device. The protective cover is mounted so that the holes are aligned with similar ones in the printed circuit board. The crimping members are inserted through the holes and are folded onto the protective cover to form a unified structure.
39 citations
Patent•
13 Sep 1990
TL;DR: A flexible metal-film laminate can comprise a layered film structure having a metal layer securely bonded to a film layer as mentioned in this paper, which can be used in the manufacture of high-quality, low-cost, flexible printed circuit boards.
Abstract: A flexible metal-film laminate can comprise a layered film structure having a metal layer securely bonded to a film layer. The laminate contains a unique metal-oxide attachment structure between the film and metal layer comprising randomly distributed regions of metal-oxide. The peel strength of such a laminate is significantly improved over prior laminates and is resistant to peel strength reduction due to environmental stress. The preferred metal-film laminates made with polyester or polyimide can be used in the manufacture of high-quality, low cost, flexible printed circuit boards.
37 citations
TL;DR: The applicability of the laser-assisted deposition process is proved for ceramics and polymers (PI, PEI, PTFE) in the fields of hybrid, flexible printed circuit boards, and molded interconnection devices as discussed by the authors.
29 citations
Patent•
27 Apr 1990
TL;DR: In this paper, a flexible printed circuit board and coverlay film is described, which has metal foil or parting paper adhered to a polyimide film using a two-layer thermosetting adhesive.
Abstract: Disclosed herein is a flexible printed circuit board and coverlay film and a method for producing the same. The board and coverlay film have metal foil or parting paper adhered to a polyimide film using a two-layer thermosetting adhesive. The first layer of adhesive on the polyimide film is about 5 μm thick or less. The circuit board and coverlay film produced according to this invention have excellent bonding strength, thermal, chemical and weather resistance, as well as good insulating properties.
27 citations
Patent•
09 Jul 1990
TL;DR: In this paper, a flexible double-sided copper-clad printed circuit base board is provided with a core resin layer of a composite material essentially composed of a specific rigid-structured polyimide and a specific flexiblestructured crosslinked polyimides.
Abstract: A flexible double-sided copper-clad printed-circuit base board is provided with a core resin layer of a composite material essentially composed of a specific rigid-structured polyimide and a specific flexible-structured crosslinked polyimide silicone in a state of being inseparable from each other, wherein the core resin layer is formed directly between two copper foils. This base board is produced by coating a surface of a copper foil with a polyamic acid solution mixture of a specific polyamic acid and a specific polyamic acid - alkylsilane, heat-treating the resulting coated copper foil, and contact-bonding another copper foil to the resulting copper-foil/polyimide laminate.
25 citations
Patent•
21 May 1990TL;DR: In this article, a mounting apparatus for a flexible printed circuit board of a lens which moves in an optical axis direction and has a shutter unit provided thereon is disclosed, which is connected at one end to the shutter unit and is bent at least twice to be connected to a control circuit provided on the camera body.
Abstract: A mounting apparatus for a flexible printed circuit board of a lens which moves in an optical axis direction and which has a shutter unit provided thereon is disclosed. The flexible printed circuit board is connected at one end to the shutter unit and is bent at least twice to be connected to a control circuit provided on the camera body. A part of the flexible printed circuit board is received in an axially extending receiving groove which is formed in an annular member of the lens. One of the bent portions of the flexible printed circuit board is located in the receiving groove. A securing member is provided to hold the bent portion of the flexible printed circuit board located in the receiving groove between the securing member and the bottom of the receiving groove.
24 citations
Patent•
17 Dec 1990TL;DR: In this paper, a supporting apparatus for a flexible printed circuit board includes a shutter holding frame which is integrally provided on the rear end of a shutter unit, and a frictional keeping member which frictionally holds the flexible circuit board which extends rearwardly from the front end of the shutter unit.
Abstract: A supporting apparatus for a flexible printed circuit board includes a shutter holding frame which is integrally provided on the rear end of a shutter unit, and a frictional keeping member which frictionally holds the flexible printed circuit board which extends rearwardly from the front end of the shutter unit, along the circumference thereof, so as to extend along the rear end of the shutter holding frame.
24 citations
Patent•
31 Oct 1990
TL;DR: In this article, a rotary member rotatable around a shaft mounted on a base and attached to a flexible printed circuit board is attached to the rotary and the board is pushed by a pushing member mounted on the base so that the direction of an elastic force exerted by the bending of the flexible circuit board against the rotating member coincides approximately to the center axis of the shaft.
Abstract: An apparatus having a rotary member rotatable around a shaft mounted on a base and to which a flexible printed circuit board is attached. The flexible printed circuit board is attached to the rotary member at an end thereof, and is fixed via the base at the other end thereof. The flexible printed circuit board has a bent portion between both ends thereof. The bent portion of the flexible printed circuit board is pushed by a pushing member which is mounted on the base so that the direction of an elastic force exerted by the bending of the flexible printed circuit board against the rotary member coincides approximately to the center axis of the shaft irrespective of the position of the rotary member. As a result of that a moment around the shaft, caused by the elastic force, to which moment the rotary member is subjected, is approximately zero.
Patent•
20 Sep 1990
TL;DR: In this article, a wide range of a preparation control system can be executed by mounting a non-contact signal transmitter group and an electronic part group on a flexible printed circuit board and molding a mounting PCB from a flexible agent.
Abstract: PURPOSE: To execute a wide range of a preparation control system by mounting a non-contact signal transmitter group and an electronic part group on a flexible printed circuit board and molding a mounting printed circuit board from a flexible agent. CONSTITUTION: Since an IC tag 9 is constituted of a flexible tape-like printed circuit board 1, a flexible protective tape 6 and a flexible filler 7, the whole of the IC tag 9 has a flexible structure and, therefore, the IC tag can be closely bonded to a body 17 having a curved surface. Since the IC tag 1 is formed in a tape shape, a laminated electromagnetic coil having a flat shape limitless along the tape length direction can be used as a non-contact transmitter-receiver 2 and, for example, even when the distance between the non-contact transmitter- receiver 2 and an external read/write head 16 is about 0.5mm or more, transmission and reception become possible in low power consumption. By this constitution, a wide range of a production control system can be executed. COPYRIGHT: (C)1992,JPO&Japio
Patent•
19 Jun 1990TL;DR: A card edge connector with flexible printed circuit film was proposed in this paper for electrically interconnecting circuits on two circuit boards through flexible circuit film mounted in the connector and with the contact pads thereon being biased outwardly by coil springs behind the contact pad.
Abstract: A card edge connector with flexible printed circuit film. More particularly a card edge connector for electrically interconnecting circuits on two circuit boards through flexible printed circuit film mounted in the connector and with the contact pads thereon being biased outwardly by coil springs behind the contact pads.
TL;DR: In this paper, an interconnection technology was described that utilizes excimer laser drilled vias and computer controlled plating to provide vertical (Z-axis) electrical connections in high-performance flexible circuits.
Abstract: An interconnection technology is described that utilizes excimer laser drilled vias and computer controlled plating to provide vertical (Z-axis) electrical connections in high-performance flexible circuits. Specifically, solid vias and hemispherical microcontacts are created with a 1- mu m nearest-neighbor height precision for the microcontacts. An architecture with a novel structure is employed to simplify the ground plane connections for impedance controlled flex circuits. The rationale for material and unit-process selection is described. The laser drilling of holes for the vertical interconnects is outlined. The deposition of the metal interconnects is considered. The performance of the resulting structures is characterized. This technology was implemented with a polyimide substrate and nickel contacts. >
Patent•
05 Feb 1990
TL;DR: In this paper, a straight copper foil circuit is formed by etched foil method on a polyimide film, and masks are formed at regular intervals in the direction of the length of the circuit on the grand patterns 3 at the edged of the copper wire circuit.
Abstract: PURPOSE:To obtain an FPC withstanding bending by forming a copper foil wiring circuit on the surface of a heat resistant plastic film, and forming an undercoat layer, a conductive paste shield layer, and an overcoat layer in this order on the circuit. CONSTITUTION:A straight copper foil circuit 1 is formed by etched foil method on a polyimide film 2. Masks are formed at regular intervals in the direction of the length of the circuit on the grand patterns 3 at the edged of the copper foil circuit 1 and paste of epoxy melamine resin is applied to form an undercoat layer 4. A through hole 5 is formed in the ground patterns 3 with the masks. conductive paint is applied and hardened by heating to form a shield layer 4, which is connected with the ground patterns 3 through the through holes 5. A thermosetting coating material is applied on the shield layer 7 and hardened by heating to form an overcoat layer.
Patent•
28 Sep 1990
TL;DR: In this paper, an elastic flat plate is placed on the back of a printed circuit resin board to align a print pattern by pressing the connecting part using a glass plate from the rear of a flexible printed circuit board and irradiating laser beams along the surface of the bonding part.
Abstract: PURPOSE:To accurately bond a print pattern and improve reliability by placing an elastic flat plate on the back of a printed circuit resin board, aligning by pressing the connecting part using a glass plate from the rear of a flexible printed circuit board and irradiating laser beams along the surface of the bonding part. CONSTITUTION:A rubber sheet 6 is placed on the surface of a flat fixed table 5, then, a printed circuit resin board (PCB) 1 is mounted on the top of the rubber sheet 6 permitting a print pattern 1a to be the top. Flexible printed circuit board (FPC) 2 is overlapped so as to permit the print pattern 2a of the FPC 2 to be correctly bonded with the PCB1, the FPC2 is pressed on the PCB1 below through a transparent glass flat plate 3 and the both print patterns 1a and 2a are aligned. Then, laser beams 4 are irradiated from the rear of the transparent glass plate 3 by the fixed power, spot radius and scanning speed, which are previously set. Thus, the solder deposited on the connecting edge part of the print pattern 2a forms solder film on the surface and side planes of the print pattern 1a of the PCB1 by the suitable thickness and the connection is completed.
Patent•
24 May 1990
TL;DR: In this article, a flexible printed circuit board of a predetermined shape is formed in a U or L shape, and then it is bent to an insulating base surface side or an insulation coating side at a bent position.
Abstract: PURPOSE: To improve a surface mounting efficiency and yield in the case of surface mounting on a working panel by forming a part or all of a circuit board in U or L shape, and bending an insulating base material side or an insulating coating surface side in a cable state. CONSTITUTION: A cable I of a flexible printed circuit board of a predetermined shape is formed in a U or L shape, bent to an insulating base surface side or an insulation coating side at a bent position (a), and then bent to an insulation coating side of an insulating base surface side at a bent position (c) in a cable state. The bending may be performed by initially bending at the bending position (c) and then bending at the bending position (a). As the insulation base material and the insulating coating material, flexible insulating plastic film such as polyimide, polyester, etc., may be employed. Thus, the flexible circuit board can be efficiently surface mounted on a working panel, and a long printed circuit board of an application range or more of a manufacturing facility can be obtained. COPYRIGHT: (C)1992,JPO&Japio
Patent•
01 Aug 1990
TL;DR: In this paper, a printed circuit resin board (PCB) is mounted on the surface of a flat base with a printed pattern 1a upside, and the printed pattern 2a of a flexible printed circuit board FPC 2 is connected with the printed patterns 1a of the PCB 1 and their sides and solder connected.
Abstract: PURPOSE: To enable satisfactory bonding even when a pitch is extremely small by brazing the surface of a joint section of a printed pattern for a flexible printed circuit board (FPC), superposing the patterns to be connected with FPC and a printed circuit resin board (PCB) so that they may face each other, positioning, and radiating laser light. CONSTITUTION: A printed circuit resin board PCB 1 is mounted on the surface of a flat base 5 with a printed pattern 1a upside. While a printed pattern 2a of a flexible printed circuit board FPC 2 to be connected with the printed pattern 1a of a PCB 1 is pressed against the PCB 1, the PCB 1 is placed upon the FPC 2 while the FPC 2 is press of the PCB 1 below by way of a transparent glass plate 3 so that both printed patterns 1a and 2a may be positioned. Then, laser light 4 is projected from the rear side of the transparent FPC 2 at a contact power, spot radium, and scanning speed. The solder melted with the joint section of the printed pattern of the FPC 2 is heated so that a solder- coated film may be formed on the gold-plated surface of the printed pattern 1a of the PCB 1 and their sides and solder-connected. COPYRIGHT: (C)1992,JPO&Japio
Patent•
26 Apr 1990
TL;DR: In this paper, an improvement is proposed in the preparation of a coverlay film, which is a laminate of a polyimide film and a releasing film with an interposed layer of a semi-cured thermosetting adhesive and used for the protection of a flexible printed circuit board.
Abstract: An improvement is proposed in the preparation of a coverlay film, which is a laminate of a polyimide film and a releasing film with an interposed layer of a semi-cured thermosetting adhesive and used for the protection of a flexible printed circuit board, relative to the dimensional stability thereof. The improvement comprises (a) decreasing the thermal shrinkability of the polyimide base film not to exceed ± 0.05% in each direction by a low temperature plasma treatment and/or heat treatment prior to coating with the adhesive, (b) keeping the tension in the polyimide base film fed to a pair of laminating rollers not to exceed 250 g/mm², and (c) keeping the temperature of the laminating roller in contact with the running polyimide film not to exceed 100 °C.
Patent•
28 Sep 1990
TL;DR: In this paper, the authors propose that the printed circuit board consists of at least one rigid region (7) which may be secured to the component bearing the plug, especially a cover (5) of the housing (4), from which the plug can be inserted.
Abstract: The invention relates to an electronic device, especially a control device for a motor vehicle's internal combustion engine, with an electronic circuit arranged on a printed circuit board to which is allocated a multi-pin plug which passes through a housing containing the printed circuit board. The proposal is that the printed circuit board consists of at least one rigid region (7) which may be secured to the component bearing the plug, especially a cover (5) of the housing (4), from which starts at least one flexible, curved section (8) of the printed circuit board.
Patent•
14 Dec 1990
TL;DR: In this article, the output terminals of a flexible printed circuit board (COF) are formed to be perpendicular to the output and parallel to other input terminals, and the signal wires are soldered to the input terminals.
Abstract: PURPOSE:To dispense with a 2-layer printed circuit board by forming output terminals for connections with a display device on one side of a flexible printed circuit board carrying a LSI chip and forming input terminals on the two sides which are perpendicular to the selected side. CONSTITUTION:Input terminals 2a-h for a flexible printed circuit board (COF) 4 are formed to be perpendicular to the output terminals 1 and parallel to other input terminals. After that, the signal wires 5B-G of a printed circuit board 8 which is a one-sided board not requiring upper and lower continuity achieved by through holes are soldered to the input terminals 2a-h of COF 4. Further, a liquid crystal device 7 and output terminals 1 are connected by an anisotropic conductive adhesive agent.
Patent•
16 Nov 1990
TL;DR: In this paper, the authors proposed a method to perform soldering without causing the deviation in the position between an IC chip and a printed circuit board without generating thermal deformation on the circuit board by heating locally the chip positioned on a collet by reflected light of a laser beam.
Abstract: PURPOSE:To perform the soldering without causing the deviation in the position between an IC chip and a printed circuit board without generating thermal deformation on the circuit board by heating locally the chip positioned on the circuit board by a collet by reflected light of a laser beam CONSTITUTION:The IC chip 3 is positioned on the flexible printed circuit board 2 mounded on a sample base 1 in the state with the central part of the IC chip 3 sucked on the collet 15 capable of reflecting the laser beam 8 from a peripheral part and solder bumps 6 of the IC chip 3 are allowed to correspond to electrodes on the printed circuit board 2 In this state, the IC chip 3 is press- contacted on the printed circuit board 2 and the laser beam 8 reflected from the peripheral part of the collet 15 is made incident on the rear parts of the solder bumps 6 of the IC chip 3 to melt the solder bumps As a result, unnecessary heat is not supplied to the printed circuit board 2 Accordingly, the thermal deformation or thermal deterioration is not generated and the deviation in the position between the IC chip 3 and the flexible printed circuit board 2 is not caused
Patent•
13 Feb 1990
TL;DR: In this article, a flexible printed-circuit board is held by magnetic attraction by using a magnetic force during its conveyance operation, so that the board is not warped by a thermal stress which is exerted during the operation.
Abstract: PURPOSE:To enable close contact of a bonding region with a carrier surely and flatwise by a method wherein, in a state that a flexible printed-circuit board has been sandwiched and held between a carrier and a conveyance hold- down metal fitting equipped with a magnet, the printed-circuit board is conveyed to a prescribed bonding position and a bonding operation is executed. CONSTITUTION:Magnets 4 are fit into the rear surface of a conveyance hold- down metal fitting 3; a flexible printed-circuit board 2 is conveyed in a state that it has been sandwiched and held between a carrier 1 and the conveyance hold-down metal fitting 3 so as not to be displaced; the board is bonded in a sandwiched and held state also during a bonding operation. Since the flexible printed-circuit board 2 is sandwiched and held by attraction by using a magnetic force during its conveyance operation, it is not warped by a thermal stress which is exerted during the conveyance operation; during the bonding operation, the board can be placed on the carrier 1 irrespective of its shape in a state that its flatness has been maintained surely. Thereby, the bonding operation can be executed in the state that the flatness has been maintained surely in a bonding position.
Patent•
17 Jan 1990
TL;DR: In this paper, a flexible printed circuit is connected with an anisotropic conductive film, and the exposed part of the terminal 2 and the window 11 are coated with epoxy resin from above the circuit 3, cured at predetermined temperature.
Abstract: PURPOSE:To connect with easy and sufficient adhering strength by removing a resin film of a part isolated from the end of the connecting terminal of a flexible printed circuit, providing a window completely exposed with a conductive layer, electrically connecting between predetermined connecting terminals, then coating a board with an adhesive through slits, and curing it. CONSTITUTION:A window 11 in which resin film 10 is removed is formed at a position isolated from the end of the connecting terminal 9 of a flexible printed circuit 3. A conductive layer 12 is exposed in the window 11. The terminal 9 of the circuit 3 is press-bonded by an anisotropically conductive film 5 to the connecting terminal 2 of a board 1 to be electrically connected. Then, the exposed part of the terminal 2 and the window 11 are coated with epoxy resin 6 from above the circuit 3, cured at predetermined temperature, and the circuit 3 rigidly adheres to the board through the window 11. According to this structure, epoxy resin 6 so adheres directly to the board 1 as to hold the circuit 3, thereby providing sufficiently mechanical adhering strength.
Patent•
23 May 1990
TL;DR: In this article, a flexible printed circuit board with excellent dimensional stability and stable quality was obtained by laminating a polyimide film made to be a specific dimensional contraction rate and metallic foil through a surface treatment and/or drying, at this time specifying the tension of the film and film side heat rolling temperature.
Abstract: PURPOSE:To obtain a flexible printed circuit board with excellent dimensional stability and stable quality by laminating a polyimide film made to be a specific dimensional contraction rate and metallic foil through a surface treatment and/or drying, at this time, specifying the tension of the film and film side heat rolling temperature. CONSTITUTION:A polyimide film raw material is made -0.05% in its dimensional contraction rate of both longitudinal direction and width direction such that it is given a surface treatment by the low temperature plasma of inorganic gas, or heat-treated sufficiently at the temperature of 80 - 200 deg.C, or used jointly with both of them. The polyimide film is coated with a thermosetting adhesive agent, and made a semi-cured condition by evaporating and removing a solvent, and then laminated with metallic foil by heating rolls. At this time, the tension of the film is restrained low to be 3kg or below at the film width 500mm conversion, and the temperature of film side heat rolls is made 60 - 120 deg.C for laminating them at low tension and low temperature. Through this manner, any creases never occur on the metallic foil, thereby manufacturing a flexible printed circuit board with excellent dimensional stability and appearance.
Patent•
12 Jan 1990
TL;DR: In this paper, the printed circuit parts are formed by etching on the surface of a long insulating thin sheet 1 and the thin sheet is stuck on a peeling board 4 with a double adhesive tape 5.
Abstract: PURPOSE:To continuously arrange FPC substrates on a paste board with good positional accuracy by sticking an insulating thin sheet, wherein a plurality of the printed circuit parts are formed, on a peeling board with a double adhesive tape while cutting only an insulating thin sheet along the printed circuit parts. CONSTITUTION:A plurality of printed circuit parts 3 are formed by etching on the surface of a long insulating thin sheet 1. The thin sheet 1 is stuck on a peeling board 4 with a double adhesive tape 5. Board perforations 6, terminal holes 7 of the circuit parts 3 are opened, while half-cutting along the circuit parts 3 for cutting off only the thin sheet 1. When the thin sheet of the part excepting the circuits 3 are peeled from on the board 4, a structure, wherein the FPC substrates 3 are arranged with good accuracy on the board 4, can be obtained. The substrates can be arranged during the manufacture of the FPC substrates.
Patent•
26 Feb 1990
TL;DR: In this paper, the authors proposed a method to carry out impedance control by forming electric connections as to make resistance and relative impedance properties practically equal to respective connections of circuits regarding connectors and circuit boards.
Abstract: PURPOSE: To carry out impedance control by forming electric connections as to make resistance and relative impedance properties practically equal to respective connections of circuits regarding connectors and circuit boards. CONSTITUTION: Electric connectors 10 are installed in end parts of a printed circuit board 12, reception parts of the connectors 10 are connected with respective conductor pads P on a circuit board 12 by flex circuits 14, 14' having mutual connections, and for the mutual connections, circuit impedance which is practically equal to a couple of mutual connections is used. In this way, multiple rows of connectors are electrically connected with a printed circuit board as to make impedance of mutual connection circuits, especially resistance, be equal to that of each circuit path. Consequently, an interface with controlled impedance can be obtained.
Patent•
19 Sep 1990
TL;DR: In this paper, a coaxial - microstrip line converter with a flexible printed circuit board with a structure of capacitance was proposed to improve the matching characteristic of the coaxial connector.
Abstract: PURPOSE:To obtain a coaxial - microstrip line converter eliminating the effect of an inductance of a conductive ribbon and improving the matching characteristic by connecting a microstrip line and a coaxial line with a flexible printed circuit board with structure of capacitor CONSTITUTION:Since a flexible printed circuit board 5 acts like a capacitor with a structure of a dielectric sheet 6 inserted between flexible conductor films 7, 8, the board has an electric capacitive reactance and forms an LC circuit with an inductive reactance parasitic to the flexible conductor films 7, 8 When the constants of the LC are set properly, suitable impedance matching is attained for the coaxial connector 2 and the microstrip line 4 Moreover, the capacitance is adjusted by the type of material, thickness or area or the like of the dielectric sheet 6 and the inductance is adjusted by the width or length of the flexible conductor films 7, 8
Patent•
30 May 1990
TL;DR: In this paper, a circuit conductor made of a copper foil is interposed integrally between a polyimide base film and a Polyimide cover lay film to improve heat resistance, wire bonding properties, and bending characteristic at a high temperature.
Abstract: PURPOSE:To improve heat resistance, wire bonding properties, and bending characteristic at a high temperature by integrating upper and lower polyimide film layers through circuit conductors. CONSTITUTION:A circuit conductor 2 made of a copper foil is interposed integrally between a polyimide base film 1 and a polyimide cover lay film 3. Thus, since adhesive is not employed, characteristics are not reduced due to the adhesive, and the thickness and hardness of the used polyimide film can be controlled. In this manner, its heat resistance is remarkably improved, wire bondability at a high temperature is improved, and bending characteristic can be improved merely by controlling the thickness, and the hardness of the polyimide film itself.