JPH11167352A - Article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable termination of a connecting cable at a low temp. to a display panel and a controller by an ultrasonic treatment. SOLUTION: This article has a flat panel display unit which is arranged with plural conductive lead pads on its surface and a microminiaturized signal transmission flat cable 10 which has a first end and a second end facing each other. The first end of the cable 10 is electrically connected to a selected number of the lead pads. The cable 10 has at least one support film 12 which has a first surface 18 and a second surface 20 facing each other and is thinner than about 0.0762, at least one adhesive layer 14 which is arranged on the first surface 18 of this supporting film 12 and is thinner than about 0.0254 mm and a signal transmission body 16 which is smaller in width size than about 0.0508 mm and is embedded into the adhesive layer. The article has a means electrically connected to the second end of the cable 10 in order to electrically control the flat display unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates generally to flat display devices and, more particularly, to an improved electrical interconnect for electrically connecting a flat display device to an electronic drive circuit component.

[0002]

BACKGROUND OF THE INVENTION Before flat or flat panel displays were developed, cathode ray tubes or CRTs were the primary electronic devices for displaying information. As can be seen from U.S. Pat. No. 5,577,944 to Taylor, CRTs
It requires considerable depth and is relatively brittle and heavy, which limits it to being used, for example, in laptops or portable computers. Flat or flat panel displays, as the name implies, have been considerably developed over the last few years because of their relatively small depth and display characteristics that are comparable to those of CRTs.

[0003] Today, flat panel displays with liquid crystal displays are almost universally used in laptop computers, mobile phones, portable small wireless callers,
And other electronic devices. Moreover, such displays are commonly used in avionics on commercial or military aircraft. Conventionally designed flat panel displays have a substrate such as a glass plate having a plurality of rows and columns of conductors etched on the plate. Each of the row and column conductors extends to the periphery of the plate for connection with a drive circuit component, which is configured to form a pattern in a display area based on data to be displayed. It is selectively excited. Generally, the drive circuit components are the type of integrated circuit used to drive a selected group of conductors from around the horizontal and vertical rows. Typical drive circuits are capable of driving individual conductors at locations where the drive circuit receives input signals provided by electronics outside the panel.

[0004] Interconnection devices between drive circuit components and the display substrate have gained increasing attention. Current technology for interconnecting devices between drive circuit components and a substrate consists of flexible printed or flexible circuits, and anisotropic conductive films (referred to as "ACF"). The flexible circuit comprises an ACF sandwiched between the flexible circuit and the display glass plate.
By applying heat and pressure to the display glass plate. In this way,
A conductive path is formed from the lower conductive trace of the flexible circuit through the ACF to a conductive trace on the upper surface of the display substrate (such as a glass plate). Further, the ACF forms a mechanical bond between the flexible circuit and the display glass.

[0005]

SUMMARY OF THE INVENTION Flexible circuits / ACFs
Has several problems. For example, known ACF materials have limited operating temperatures. However, many flat panel display applications require that they be used and / or stored in environments at temperatures that exceed the operating limits of readily available materials. Previously, the material of the liquid crystal display was the limiting factor, but in recent display technology, for example, a field emission display (“FE
D ") can be stored or used at temperatures higher than the operating temperature of readily available ACFs. Therefore, the flexible circuit / ACF interconnect device allows the display to operate in hot environments. Is a limiting factor for use or storage.

[0006] Another limitation due to the flexible circuit / ACF interconnect device is that the ACF requires a high temperature curing process to form the connection. Currently known ACF materials cannot be terminated at room temperature. Therefore, new types of display materials, such as those made from thermoplastic materials, cannot withstand ACF termination.

Another problem with flexible circuit / ACF bonding techniques is that the contact resistance per unit contact area between the flexible circuit and the ACF, and therefore between the ACF and the display substrate, is reduced. ACFs typically require a minimum edge width of about 1.5 mm for termination, because a suitable contact area is needed to compensate for the high. The width of the edge can be reduced only when the pad pitch is increased. Many flat panel display applications, such as those used in avionics, require the edge width to be minimized. Some of the reasons for this are not to be heavy, to make more efficient use of the available space, and to save costs by increasing the number of display devices that can be made with panels of a given size. included.

Furthermore, ACF requires a termination circuit board connected to the driver die or chip package, ie, the ACF or interconnect device cannot be directly connected to the driver die. In fact, other currently available interconnect methods do not directly attach the interconnect device to the driver die. By directly terminating the die, one packaging step can be eliminated in the assembly process, thus saving costs and improving reliability.

[0009] Other methods of interconnecting the driver to the glass plate are known. For example, the driver die can be mounted directly around the glass. The connection of the driver die to the glass can be achieved by any suitable conventional method. The main problem with this technique is that it requires an increased edge area to attach the die. In this application, rework is known to be difficult and therefore the display is discarded. Heat sealing has also been used to interconnect drivers to glass plates. Although heat seals have the advantage of being able to withstand higher temperatures than ACFs, they are limited in that a pitch of at least 120 μm is required for most displays, at most a pitch of about 70 μm.

It is known that the above-mentioned limitations exist in current display device interconnect devices. Clearly, it would be advantageous to provide an improved interconnection device that overcomes one or more of the limitations set forth above. Accordingly, suitable alternatives are provided having the features described in more detail below.

[0011]

SUMMARY OF THE INVENTION The present invention advances the art of flat or flat panel display devices and related manufacturing methods beyond currently known techniques. In one embodiment of the present invention, the article is flat
It has a panel display unit, and a plurality of conductive lead pads are arranged on a surface of the flat panel display unit. The article further includes a flat microminiaturized signal transmission cable having opposing first and second ends. The first end of the cable is electrically connected to a selected number of conductive lead pads. The cable further has at least one support film having opposing first and second surfaces, wherein the thickness of the support film is less than or equal to about 0.003 inches (0.0762 mm). At least one adhesive layer is disposed on the first surface of the support film, wherein the adhesive layer is about 0.001 inches (0.5 mm).
0254 mm). About 0.0 width
At least one preformed signal transmission conductor of no more than 02 inches (0.0508 mm) is embedded in the adhesive layer. The article further has control means electrically connected to the second end of the cable for electrically controlling the flat panel display.

It is therefore an object of the present invention to provide an article comprising a display panel, electronic drive circuit components, and an interconnect device therebetween, wherein the interconnect device comprises:
It is an object of the present invention to provide an article that can be wire-bonded to a low-temperature plastic substrate by ultrasonic treatment at room temperature.

It is another object of the present invention to increase the maximum storage and / or use temperature of articles over prior art interconnect devices.

Another object of the present invention is to reduce the edge area around the perimeter of the display area of the article.

It is another object of the present invention to allow an article to be directly connected to a driver die, thus eliminating at least one packaging step.

It is another object of the present invention to mass produce articles at a lower cost than other articles, and to reduce the time required for manufacture and installation compared to other interconnect devices of the prior art.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing summary, as well as the following detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. To illustrate the present invention, the drawings show a presently preferred embodiment. However, it should be understood that the present invention
It is not limited to the illustrated devices and means themselves.

In the drawings, like reference numerals indicate like parts throughout the several views, and the flat, miniaturized signal transmission cable of the present invention is indicated generally at 10 in FIGS. As shown in the figures, cable 10 has three main components: a support film 12, an adhesive layer 14 deposited on the support film, and a plurality of conductors 16 attached to the adhesive layer. It should be understood that the cable 10 can have any number of support films 12 and adhesive layers 14 as needed for strength and rigidity without departing from the scope of the present invention. Further, the cable 10 can be manufactured with any number of conductors 16 as well.

The support film 12 has an upper-facing (first) surface 18 and, conversely, a lower-facing (second) surface 2.
0. As shown in FIG. 2, the upper facing surface 1
The adhesive layer 14 is disposed on the surface 8. Preferably, the support film 12 of the cable 10 is made from any suitable polymer material, for example, a polyimide. (This material is commercially available on spools or reels,
Available from UBE Industries, Ltd. under ILEX®. ) Due to the support film 12, the cable has the required strength and rigidity. Preferably, the support film 12 has a thickness of less than about 0.003 inches (0.0762 mm). The support film 12 can be made of polyester or a fluoropolymer such as, for example, porous polytetrafluoroethylene, polytetrafluoroethylene, fluorinated ethylene propylene, or a perfluoroalkoxy polymer.

In this regard, the porous polytetrafluoroethylene ("PTFE") used herein may be, for example, a stretch or stretch process, a papermaking process, where the filler material is included with the PTFE resin and subsequently removed to remove the porous material. A film that can be made by any of a number of known processes, such as forming a structure or a powder sintering process. Preferably, the porous PTFE is a porous expanded polytetrafluoroethylene membrane having an interconnected node and fibril microstructure described in U.S. Patent Nos. 3,953,566 and 4,187,390, which are incorporated herein by reference. It is. U.S. Pat. Nos. 3,953,566 and 4,187,390 fully describe suitable materials and processes for making them.

Adhesive layer 14 is deposited on first surface 18 of the support film by any suitable device. If there is a gap in the layer, the conductor 16 may be inappropriately bonded to the support film 12.
Is important to have a uniform thickness and density. Preferably, the adhesive layer 14 is a cross-linked blend of polyester polymers. The thickness of the adhesive layer 14 is preferably set at 0.
001 inches (0.0254 mm) or less.

One preferred method of applying the adhesive layer 14 to the support film 12 is to liquefy the adhesive by adding a solvent to the adhesive and to apply the liquefied adhesive / solvent mixture to the first of the support film. Is attached to the surface 18.
After application of the mixture, the support film 12 is subsequently dried (by air or mechanically), so that the solvent is stripped off. Subsequently, the adhesive layer 14 is used for flattening.
Can be treated by a doctor blade or other similar device. During this attaching process, the support film 12 is moved from the spool or reel, and once the adhesive layer 14 is cured, it is taken up on another spool.

The preformed conductor can be of any suitable shape, and may be about 0.002 inches (0.02 inches).
508 mm). Cylindrical conductors are commonly used and have good responsiveness to ultrasonic bonding. Rectangular conductors can be used as well. The conductor 16 may be made of, for example, gold, aluminum, gold-plated copper, aluminum containing silicon,
Manufactured from metals such as copper, aluminum, aluminum magnesium alloy and tungsten, it is therefore possible to bond between conductors and metal flat pads by conventional bonding methods. When a plurality of conductors 16 are required, the conductors are arranged on the same plane in parallel at predetermined intervals. Generally, conductor 16
Are spaced at intervals ranging from about 0.0015 inches (0.0381 mm) to about 0.0100 inches (0.254 mm).

The material for conductor 16 is selected based on a number of criteria, the most important being the compatibility of the material from which the conductor is terminated. One combination that has been used is Amer
1% silicon added aluminum manufactured by icanFine Wire. The conductor 16 formed from this material may be a molybdenum dioxide pad (or "trace (t
race) "). Other factors affecting the choice of conductor material include flexural strength, hardness, conductivity and elongation.

Furthermore, the conductor 16 can be pre-insulated or exposed. If the conductor is pre-insulated, the insulator is removed or bonded by an ultrasonic method. If the insulator is removed, an excimer laser is the preferred method because it has high accuracy and reliability to completely remove the insulator from the conductor.

The conductor 16 is embedded in the adhesive layer 14 by any suitable method using force or temperature. The conductors 16 are aligned and spaced in the required configuration and are preferably passed through a nip location (of a pass-through roller). In the nip position, the support film 12 and the conductor 1
6 can be warmed to ensure proper bonding between them. After bonding the conductor 16 to the support film 12, the cable 10 is cooled and collected in any known manner.

As mentioned above, the individual conductors 16 are provided by a suitable layer of insulating material (not shown) such as, for example, polyurethane, polyimide, porous polytetrafluoroethylene, polytetrafluoroethylene, or fluorinated ethylene propylene. Can be insulated. The individual conductors 16 can be individually insulated by conventional methods such as, for example, extrusion, tape wrapping, or dip coating. It is further anticipated that conductor insulating materials having a higher melting temperature than the material used for support film 12 may be used to facilitate processing in certain cases.

It should be noted that in addition to the foregoing, one or more ground planes (not shown) can be included in any embodiment of the present invention. A suitable ground plane material can be a metal foil or other conductive material. A particular embodiment of the present invention is that the thickness of the support film 12 and the adhesive layer 14 are 0.003 inch (0.0762 mm) and 0.001 inch (0.02 mm), respectively.
54 mm). As mentioned above, one or more support films 12 can be used. The width of each support film 12 must be approximately equal to or greater than the width of the finished cable 10. Alternatively, one or more adhesive layers 14 can be used as an unrestrained film on one or more support films 12 and / or as a coating.

The production equipment for forming the cable 10 of the present invention comprises machined drums and / or rollers. Therefore, the cable components (such as, for example, support film 12, adhesive layer 14, and conductor 16 described above)
They are formed together by successive steps under heat and / or pressure. The conductors 16 and / or the support film 12 are navigable such that their position relative to each other is controlled. The production facility is machined to hold each conductor 16 in place. Further, the production equipment can be heated,
Alternatively, heat can be applied to some or all of the cable components before they enter the production facility. The elevated processing temperatures and times at which the components are retained are selected so that the conductor 16 is embedded within the adhesive layer 14.

After the cable 10 has been formed, the edges are trimmed to remove excess material, and the dimensions of the finished cable and / or the spacing from each edge to each conductor 16 are controlled. Is done. This is done by any suitable method, such as for example a rotating blade, a stationary blade and / or a laser. The cable 10 of the present invention can be prepared for termination prior to conductor embedding by removing a portion of the support film 12 near one or both ends (eg, by laser stripping). It is possible. This makes it possible to move the cable 10 in the free axial direction, for example for wiring on the termination pads.

3 and 4, which illustrate one embodiment of the present invention, a flat or flat panel display device or article is indicated generally at 22. FIG. It should be understood that a flat panel display device can be, for example, a liquid crystal display, a field emission display, or a CMOS.
Any embodiment, such as a type display, is possible.
By way of example, and not limitation, the flat panel display device 22 includes a cathode plate 24, an anode plate 26, and a display area 28. As shown in FIG. 3, the periphery of the display area 28 is an edge 30 having a width sufficient to accommodate the connection of the transmission cable 10 to the display area 28. As shown in FIG. 4, the cathode plate 24 of the display device 22 has a plurality of lead pads or traces, each indicated at 32. Lead pad 3
2 is manufactured from a metal material suitable for electrical bonding to the conductor 16 of the cable 10. The preferred method of bonding the cable conductor 16 to the metallized lead pads 32 is ultrasonic bonding. Anisotropic conductive films ("ACF") can also be used to bond materials together. In particular, ACF bonding consists of placing a conductive particle filling material (such as, for example, an ACF film, liquid or paste) between conductor 16 and lead pad 32. A heated tool is biased onto the cable 10 so that heat and pressure provide an electrical connection between the conductor 16, the conductive ACF particles and the lead pad 32. The conductor 16 can also be bonded to the lead pad 32 by cold termination when the cathode plate 24 is made from a polymeric material that cannot withstand high temperatures. Low temperature termination methods are well known from the prior art.

FIGS. 5 and 6 show an embodiment of the present invention.
, The transmission cable 10 is connected to the cathode plate 24 by a driving circuit component 3 such as a display driver.
4 is connected. As shown in the drawing, drive circuit component 3
4 is attached to the lower side of the printed wiring board 36 laminated on the lower side of the cathode plate 24. At least one connection 38 connects transmission cable 10 to drive circuit component 3.
4 are electrically interconnected. By miniaturizing the cable 10, the cable 10 is connected to the lead pads 3 while reducing all the edge areas 30 of the display device 22.
2 (FIG. 4) can be electrically interconnected.

In FIG. 7 showing another embodiment of the present invention, the transmission cable 10 is directly connected to the drive circuit component 34. This is another advantage associated with using the transmission cable 10 of the present invention.

As best shown in FIG. 8, the transmission cable 1
0 is electrically connected to a semiconductor device, such as a video display driver die 40, for example. In the embodiment of the present invention shown in FIG. 8, the display panel 42 is mounted on the driver die 40.

While a number of exemplary embodiments of the present invention have been described in detail, those skilled in the art will readily recognize that numerous modifications may be made without departing significantly from the novel teachings and advantages described herein. It is possible to make changes.
Therefore, all such modifications are intended to be included within the scope of this invention as limited by the appended claims.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view of a miniaturized flat signal transmission cable used to connect an electronic control circuit (not shown) to a flat display device (not shown).

FIG. 2 is an enlarged cross-sectional view of the transmission cable shown in FIG.

FIG. 3 is an enlarged plan view of a transmission cable similar to the transmission cable shown in FIGS. 1 and 2 disposed on a flat panel display.

FIG. 4 is an enlarged plan view of a transmission cable connected to metallized traces provided on a flat panel display.

FIG. 5 is an enlarged perspective view of a transmission cable for connecting a driving circuit component to a flat panel display.

6 is an enlarged side view of the flat display device shown in FIG.

FIG. 7 is a view similar to FIG. 6 showing the transmission cable directly connected to the driver die.

FIG. 8 is a partial plan view of a miniaturized flat signal transmission cable electrically connected to a driver die with a display substrate attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Flat cable miniaturized signal transmission 12 ... Support film 14 ... Adhesive layer 16 ... Conductor 18 ... Upper surface (first) surface 20 ... Lower surface (second) surface

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Jay. Scott Reynolds, Senior United States, Arizona 85283, Temp, South Bonnerden Lane 5918 (72) Inventor Robert A. Russell United States, Arizona 85018, Phoenix, Each Pinchot Avenue 4113

Claims (21)

[Claims] 1. A flat display unit comprising: a flat display unit; a microminiaturized flat signal transmission cable having opposing first and second ends, wherein the first end is Electrically connected to a flat display unit,
The ultraminiaturized flat signal transmission cable has opposed first and second surfaces and a thickness of about 0.0
At least one support film that is no greater than 762 mm (0.003 inches); and is disposed on the first surface of the support film and has a thickness of about 0.0254 mm.
(0.001 inch) or less, and at least one preformed signal transmission having a width dimension of about 0.0508 mm (0.002 inch) or less and embedded in the adhesive layer. And a control means electrically connected to the second end of the microminiaturized flat signal transmission cable to electrically control the flat display unit. Goods. 2. The article of claim 1, wherein the conductor is made from the group consisting of silicon containing aluminum, copper, gold plated copper, aluminum, aluminum magnesium alloy, gold and tungsten. 3. The article of claim 1, wherein said support film is made from polyimide. 4. The article of claim 1, wherein said support film is made from the group consisting of polyester, polyimide, porous polytetrafluoroethylene, polytetrafluoroethylene, and fluorinated ethylene propylene. 5. The article of claim 1, wherein the adhesive layer comprises a cross-linked blend of a polyester polymer. 6. The support film has a first end and a second end, and a first end and a second end of the support film for facilitating attachment of the conductor to a lead pad. The article of claim 1, wherein a portion is removed from the two ends. 7. The article of claim 1, wherein the conductor is bonded to a lead pad. 8. The conductor of claim 7, wherein said conductor is bonded to said lead pad by ultrasonic welding. 9. The article of claim 1, wherein the flat panel display unit has a plastic substrate. 10. A flat panel display unit, comprising: a plurality of conductive lead pads disposed on a surface of the flat panel display unit; and a first end and a second end facing each other. A microminiaturized signal transmission flat cable, wherein the first end is electrically connected to a selected number of the lead pads, the microminiaturized signal transmission flat cable comprises an opposing first And a second surface having a thickness of about 0.0762.
at least one support film that is no more than 0.003 inches (mm) in thickness and is disposed on the first surface of the support film and has a thickness of about 0.0254 mm (0.03 inches).
01 inches) or less, and at least one preformed signal transmission conductor having a width dimension of about 0.0508 mm (0.002 inches) or less and embedded in said adhesive layer. Have an article. 11. The apparatus of claim 11, further comprising control means electrically connected to the second end of the miniaturized signal transmission flat cable for electrically controlling the flat panel display unit. An article according to claim 10. 12. The article of claim 10, wherein the conductor is made from the group consisting of aluminum containing silicon, copper, gold plated copper, aluminum, aluminum magnesium alloy, gold and tungsten. 13. The article of claim 10, wherein said support film is made from polyimide. 14. The polyester film according to claim 14, wherein the support film is polyester.
The article of claim 10, wherein the article is made from the group consisting of polyimide, porous polytetrafluoroethylene, polytetrafluoroethylene, and fluorinated ethylene propylene. 15. The article of claim 10, wherein said adhesive layer comprises a crosslinked polyester polymer formulation. 16. The support film having a first end and a second end, wherein a first end of the support film and a second end of the support film are provided to facilitate attachment of the conductor to a lead pad. A predetermined portion is removed from the second end,
An article according to claim 10. 17. The article of claim 10, wherein said conductor is bonded to a lead pad. 18. The conductor of claim 17, wherein said conductor is bonded to said lead pad by ultrasonic welding. 19. The article of claim 10, wherein said flat panel display unit has a plastic substrate. 20. A flat panel display unit, comprising: a plurality of conductive lead pads disposed on a surface of the flat panel display unit; and a first end and a second end facing each other. A microminiaturized signal transmission flat cable, wherein the first end is electrically connected to a selected number of the lead pads, the microminiaturized signal transmission flat cable comprises an opposing first At least one support film having a surface and a second surface, at least one adhesive layer disposed on the first surface of the support film, and the flat panel display unit by ultrasonic bonding. An article having at least one preformed signal transmission conductor coupled to a lead pad. 21. A flat display unit having a display panel and a driver die, and a miniaturized signal transmission flat cable having opposing first and second ends, wherein: The first end is electrically connected to the driver, and the microminiaturized signal transmission flat cable has opposing first and second surfaces and has a thickness of about 0.0762 mm (0.5 mm). 0
At least one support film having a thickness of about 0.0254 mm (0.001 inch) and a thickness of about 0.0254 mm (0.001 inch) disposed on the first surface of the support film.
At least one adhesive layer having a width dimension of about 0.
0,508 mm (0.002 inches) or less and having at least one preformed signal transmission conductor embedded in the adhesive layer, and further comprising: An article comprising control means electrically connected to said second end of a miniaturized signal transmission flat cable.