TWI494807B - One-glass-solution touch panel and method of manufacturing the same - Google Patents

Description

Monolithic glass touch panel and manufacturing method thereof

The present invention relates to touch technology, and in particular to a monolithic glass touch panel and a method of fabricating the same.

In recent years, with the popularity of mobile devices such as smart phones and tablet computers with touch functions, it is becoming more and more important to reduce the production cost of touch panels and make thinner touch panels, and monolithic glass touch panels. It is one of the structures that can meet this requirement.

Referring to FIG. 1 , a conventional technique for fabricating a monolithic glass touch panel is described. First, a release layer 12 is formed on the carrier substrate 10 to form a larger support layer thereon. After the carrier 14 is finished on the support carrier, the process of the touch structure 16 is completed, and then the edges C and C' of the release layer 12 are cut, and the adhesion of the release layer 12 to the carrier substrate 10 is not good, and the carrier substrate 10 is to be carried. Separating from the film layer of the release layer 12, the support carrier 14, the touch structure 16, and the like, and attaching a glass cover (not shown) to obtain a monolithic glass touch panel. However, in the process of separating the carrier substrate 10, since the thickness of the release layer 12 and the support carrier 14 itself is relatively thin and the touch structure 16 is mainly distributed in the central region of the support carrier 14, the edge region of the support carrier 14 is easily curled when separated. Moreover, the touch structure in the edge region is prone to falling off or damaged, which in turn affects the yield of the single glass touch panel. In view of this, the present invention provides a method for manufacturing a single-chip glass touch panel, which can effectively solve Decide on this issue.

An embodiment of the present invention provides a method for fabricating a monolithic glass touch panel, comprising: S1: providing a substrate; S2: forming a carrier layer on the substrate; and S3: forming a patterned conductive layer on the carrier layer The patterned conductive layer includes a sensing electrode, and an auxiliary electrode is disposed outside the sensing electrode; S4: forming a plurality of signal wires electrically connected to the sensing electrode, and the signal wires are concentrated in the at least one bonding region, The bonding regions are located on at least one outer side of the sensing electrode; and S5: attaching a cover plate to the patterned conductive layer, and removing the substrate from the carrier layer.

Another embodiment of the present invention provides a monolithic glass touch panel comprising: a cover plate; a carrier layer having a patterned conductive layer formed thereon, including a sensing electrode and an auxiliary electrode The signal electrode is externally connected; the plurality of signal wires are electrically connected to the sensing electrode, and the signal wires are concentrated on the at least one bonding region, and the at least one bonding region is located on at least one outer side of the sensing electrode; and a bonding A glue is disposed between the cover plate and the bearing layer for engaging the cover plate and the bearing layer.

By adopting the manufacturing method of the monolithic glass touch panel of the present invention, by adding the auxiliary electrode in the edge region of the carrier layer, the stress of the bearing layer is balanced when the substrate is removed, thereby reducing the easy curling of the edge region of the carrier layer and the edge. The components in the area are prone to falling off or damaged.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

10‧‧‧Substrate

12‧‧‧ release layer

14‧‧‧Support carrier

16‧‧‧ touch structure

300, 400, 500‧‧‧ single glass trackpad

310, 410‧‧‧ substrate

320, 420, 520‧‧‧ carrying layer

322, 422, 522‧ ‧ plastic layers

324, 424, 524‧‧ ‧ buffer layer

330‧‧‧ Conductive layer

332, 432, 532‧‧‧ sensing electrodes

334, 434, 534‧‧‧ auxiliary wires

336, 436, 536‧‧‧ auxiliary electrodes

340, 440, 540‧‧‧ signal wires

350, 450, 550‧‧‧ joint glue

451, 551‧‧‧ bonding agent

360, 460, 560‧ ‧ conductive adhesive

370, 470, 570‧‧‧ circuit boards

380, 480, 580‧ ‧ cover

390, 490, 590‧‧ ‧ shading layer

332a, 332b‧‧‧electrode blocks

332c‧‧‧First wire

333‧‧‧second wire

P‧‧‧Insulation block

M‧‧‧ junction area

H ₁ ‧‧‧The first thickness of the plastic layer

H ₂ ‧‧‧second thickness of the plastic layer

C, C’‧‧‧ cutting line

Figure 1 is a cross-sectional view showing a conventional method of fabricating a single-piece glass trackpad.

2A-2D are a series of cross-sectional views according to an embodiment of the present invention for explaining the flow of the method for fabricating the monolithic glass touch panel of the present invention.

3A-3B are top views of a patterned conductive layer of the present invention in accordance with an embodiment of the present invention.

4A-4B are cross-sectional views of another embodiment of the present invention for explaining a part of the flow of the method for fabricating the monolithic glass touch panel of the present invention.

Figure 5 is a cross-sectional view showing another embodiment of the present invention.

6A-6C are top views of another embodiment of the present invention for illustrating the sensing electrodes of the monolithic glass track of the present invention.

The present invention is provided to illustrate the technical features of the present invention. The contents of the embodiments and the drawings are for illustrative purposes only and are not intended to limit the scope of the present invention. Non-essential elements may be omitted from the drawings, and different features may not be drawn to scale and are for illustrative purposes only. The present disclosure may have overlapping element symbols in different embodiments and does not represent an association between different embodiments or drawings. In addition, an element formed "above", "above", "below" or "below" another element may include an embodiment in which two elements are in direct contact, or may include other additional elements interposed between the two elements. An embodiment. The various components may be displayed at any different scale to make the illustration clear and concise.

Please refer to FIGS. 2A-2D for making an embodiment according to the present invention. A series of cross-sectional views for explaining the flow of the method for fabricating the monolithic glass track of the present invention. Referring to FIG. 2A, first, a substrate 310 is provided, and a plastic layer 322 is formed on the substrate 310. The substrate 310 serves as a mechanical support for the structure formed in the subsequent step, and may be a transparent or opaque substrate such as a glass substrate, but the material thereof is not limited thereto. The plastic layer 322 has a release ability, which may include polyimide (PI), polypropylene (PP), polystyrene (PS), acrylonitrile-butadiene-styrene resin (ABS), polyparaphenylene Ethylene formate (PET), polyvinyl chloride (PVC), polycarbonate (PC), polyethylene (PE), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), or a combination thereof . The plastic layer 322 may be a single layer or a multi-layer structure, or may be a stacked structure composed of a material having a release property of the lower layer and a material having no release property of the upper layer. The plastic layer 322 can be formed using coating or other suitable method and can have a thickness of between about 0.5 microns and about 15 microns. The plastic layer 322 of this thickness range has good optical characteristics (e.g., high transmittance) and can reduce manufacturing costs.

Subsequently, a buffer layer 324 is formed on the plastic layer 322, and the buffer layer 324 and the plastic layer 322 together form a carrier layer 320 on the substrate 310. In another embodiment, the carrier layer 320 may comprise only the plastic layer 322, ie, the buffer layer 324 is not formed. The buffer layer 324 can be formed of any transparent material. In one embodiment, the buffer layer 324 is formed of hafnium oxide and may be formed using chemical vapor deposition (CVD) or other suitable methods. In another embodiment, the buffer layer 324 may employ an adhesion promoter comprising two functionally different functional groups. More specifically, the adhesion promoter comprises an organo-organic functional group and a pro-organic material. a functional group, wherein the functional group of the organophilic material may be an amine group, a hydroxyl group, an epoxy group or the like, and the functional group of the parent material may be a hydrogenthio group or an amine. The adhesion promoter of the functional group having the two properties, such as a hydroxyl group, a phosphate group, etc., has a good adhesion to an inorganic substance or an organic substance, thereby ensuring that the buffer layer 324 can be adapted to different plastic layer materials.

Buffer layer 324 may have a thickness of between about 10 angstroms and about 3000 angstroms. The buffer layer 324 has a higher hardness than the plastic layer 322, and the buffer layer 324 of the higher hardness is matched with the carrier layer 320 formed by the ductile plastic layer 322 to have good release ability and superior load carrying capacity. The reliability of subsequent components formed on the carrier layer 320 is improved. Further, by making the plastic layer 322 and the buffer layer 324 a composite film layer, the carrier layer 320 having both good mechanical strength and release ability can be obtained.

Next, the step of FIG. 2B is performed, a conductive layer 330 is formed on the carrier layer 320, and the conductive layer 330 is patterned to form the sensing electrode 332, the auxiliary conductor 334, and the auxiliary electrode 336. Please also refer to FIG. 3A. FIG. 3A illustrates a conductive layer 330 that can be used in FIG. 2B. The conductive layer 330 is a see-through conductive material, and may include indium tin oxide, aluminum zinc oxide, zinc oxide, antimony tin oxide, tin dioxide, indium oxide, nano silver, carbon nanotubes, or a combination thereof. It is formed using physical or chemical vapor deposition, printing, evaporation, spraying or other suitable methods. The above patterning process steps can be performed by any suitable method, such as a lithography and etching step. In other embodiments, the patterned conductive layer 330 may be directly formed by screen printing, spraying, or the like. By the processing step, the sensing electrode 332, the auxiliary wire 334, and the auxiliary electrode 336 may be respectively formed on the carrier layer 320, wherein the sensing electrode 332 includes a plurality of strip electrodes. In another embodiment, the sensing electrode 332 can employ other electrode structures. The auxiliary wire 334 is formed on a region outside the sensing electrode 332 that is predetermined to form a signal wire. In this embodiment The auxiliary lead 334 is connected to the sensing electrode 332, and in another embodiment, the two may not be connected. The auxiliary electrode 336 may be disposed continuously or discontinuously on the un-arranged component outside the sensing electrode 332 and the blank inactive area of the circuit, and the auxiliary electrode 336 and the sensing electrode 332 are insulated from each other. The auxiliary lead 334 and the auxiliary electrode 336 are formed in the same step as the sensing electrode 332, and thus do not increase the manufacturing steps. In another embodiment, only the sensing electrode 332 and the auxiliary electrode 336 may be formed. The auxiliary electrode 336 formed on the periphery of the sensing electrode 332 has a certain strength. Therefore, on the one hand, when the substrate 310 is removed, the stress on the bearing layer 320 is relatively balanced, and the edge region of the bearing layer 320 can be easily curled. And the components in the edge area are prone to falling off or damaged. On the other hand, in the subsequent manufacturing process, the influence of moisture and chemicals from the periphery of the sensing electrode 332 on the sensing electrode 332 can be alleviated, thereby improving the reliability of the finally formed single-chip glass touch panel.

Referring to FIGS. 2C and 3B simultaneously, after the sensing electrodes 332, the auxiliary wires 334, and the auxiliary electrodes 336 are formed, the signal wires 340 are formed. The signal wire 340 is electrically connected to the sensing electrode 332 and is located on the auxiliary wire 334 and converges on at least one of the bonding regions M. The land M is located on at least one outer side of the sensing electrode 332. It should be noted that the position and number of the joint regions M can be adjusted according to the specific electrode structure, and are not limited to the positions and the numbers shown. By adding the auxiliary conductor 334, the resistance of the signal transmission line can be reduced, so that the signal transmission capability can be improved. The material of the signal conductor 340 may include copper, aluminum, silver, gold, molybdenum aluminum molybdenum alloy, indium tin oxide (ITO), or a combination thereof. The signal conductor 340 is used to transmit the signal generated by the sensing electrode 332 to an external circuit.

A bonding step is then performed to electrically connect the circuit board 370 to the sensing electrode 332. One end of the circuit board 370 can be bonded to the junction area by the conductive adhesive 360 The signal wire 340 of the M is electrically connected to the sensing electrode 332 by the signal wire 340, and the control chip (not shown) is connected to the other end, thereby electrically connecting the chip to an external circuit (not drawn). Shown, for example, a printed circuit board. In this embodiment, the circuit board 370 can be a Flexible Printed Circuits (FPC), and the conductive adhesive 360 can use an Anisotropic Conductive Film (ACF). The circuit board 370 can transmit the signal of the change generated by the sensing electrode 332 to the external circuit, and the coordinates of the touch position can be obtained after the IC operation and the system interpretation. The sensing electrode 332, the auxiliary conductor 334, the auxiliary electrode 336, the signal conductor 340, and the circuit board 370 formed on the carrier layer 320 constitute a body of the touch structure.

Subsequently, a bonding paste 350 is attached over the conductive layer 330. Since the bonding region M is formed with the conductive paste 360 and the circuit board 370, the bonding region M is relatively uneven with respect to other regions, and in order to achieve the bonding yield and avoid the generation of bubbles in the bonding region M when the bonding adhesive 350 is attached, the bonding is avoided. The zone M, that is, the land M is not covered by the bonding glue 350. The bonding adhesive 350 may be made of a material having good light transmittance, such as Solid Optical Clear Adhesive or Liquid Optical Clear Adhesive. The bonding paste 350 may include a transparent synthetic resin such as Acrylic. The bonding adhesive 350 can be attached to the conductive layer 330 by using a hot pressing process of heat and pressure. After the hot pressing is completed, the bonding adhesive 350 is fixed on the conductive layer 330, so that the overall strength of the touch structure can be further improved. In one embodiment, a step of bonding the bonding paste 350 may be performed to separate the plurality of touch structures formed on the same large-sized substrate, and the cutting step may be performed by cutter wheel cutting or laser cutting. The way. In another embodiment, the bonding glue 350 may be attached first, and then the circuit board 370 is bonded.

Finally, in the step of FIG. 2D, the cover 380 is attached over the touch structure, and the substrate 310 in FIG. 2C is removed from the carrier layer 320 (release). The cover 380 is used to protect the touch structure, and a transparent material such as glass can be used. In this embodiment, before the cover 380 is attached, the light shielding layer 390 may be formed on the edge of the cover 380. More specifically, the light shielding layer 390 is located on the side where the cover 380 is engaged with the touch structure. In another embodiment, the light shielding layer 390 can be located on the other side opposite the joint surface. The light shielding layer 390 is used to shield the signal wires 340 to ensure that the user does not see the signal wires 340 of the single glass track pad 300 during use, which affects the visual appearance. The material of the light shielding layer 390 may be a colored ink or a colored photoresist. The method of releasing the substrate 310 from the carrier layer 320 may be solution immersion, heat treatment, cold treatment, external force detachment, or a combination thereof. More specifically, when the solution is immersed in the solution, the solution may be water, alcohol, propylene glycol methyl ether ester (PGMEA) solution, polyvinylidene fluoride (NMP) solution, etc.; heat treatment and cold treatment are used to heat the substrate 310. Or cooling, the load-bearing layer 320 and the substrate 310 have different thermal expansion rates to generate stress and thus facilitate the release. Moreover, the order in which the cover plate is attached and the substrate is removed is adjustable, and is not limited to the above sequence.

In this embodiment, a monolithic glass touch panel having good release ability, mechanical strength, and optical properties can be obtained by using the plastic layer 322 in combination with the buffer layer 324 to form a composite film layer. At the same time, by forming the auxiliary electrode 336 outside the sensing electrode 332, the stress of the bearing layer 320 is balanced when the substrate 310 is removed, and the stability of the bearing layer 320 is improved, thereby improving the subsequent formation on the carrier layer 320. The reliability of other components and the ease with which the edge regions of the carrier layer 320 are easily curled, and the components of the edge regions are prone to detachment or damage.

Referring to FIG. 2D and FIG. 3B simultaneously, the single-panel glass touch panel 300 formed by the above process includes a cover plate 380 and a carrier layer 320. The carrier layer 320 is formed with a patterned conductive layer, including sensing. The electrode 332 is disposed on the outside of the sensing electrode 332. The signal wire 340 is electrically connected to the sensing electrode 332. The signal wire 340 is concentrated on at least one of the bonding regions M. The bonding region M is located at least one of the sensing electrodes 332. An outer side; a circuit board 370, a signal wire 340 electrically connected to the land M; and a bonding glue 350 disposed between the cover 380 and the carrier layer 320 for engaging the cover 380 and the carrier layer 320 . In the embodiment, the auxiliary layer 334 is further formed on the carrier layer 320, and the signal line 340 is located on the auxiliary line 334. The edge of the cover 380 is formed with a light shielding layer 390. More specifically, the light shielding layer 390 is located on a side where the cover 380 is engaged with the touch structure. The light shielding layer 390 is used to shield the signal wires 340 to ensure that the user does not see the signal wires 340 of the single glass track pad 300 during use, which affects the visual appearance. Other characteristics of the components of the monolithic glass trackpad 300 are detailed in the forming process thereof and will not be described herein.

Please refer to FIGS. 4A-4B , the main components and manufacturing method of the single-chip glass touch panel 400 are basically similar, except that after the circuit board 470 is bonded, in the joint area M An additional adhesive 451 is filled in the gap between the inner circuit board 470 and the carrier layer 420. By adding the adhesive 451, the stability of the carrier layer 420 when the bonding region M is peeled off from the substrate 410 can be further enhanced, and the possibility that the circuit board 470 of the bonding region M is peeled off or damaged can be reduced. The additional adhesive 451 can be made of the same material as the bonding paste 450, such as a solid optical adhesive, a liquid optical adhesive, or the like.

Please refer to FIG. 5 , the main components and manufacturing method of the single-chip glass touch panel 500 are substantially similar, and the difference is that the thickness of the bearing layer 520 at the joint M can be locally thickened. More specifically, the plastic layer 522 may have a first thickness H ₁ at a land M of a predetermined bonding circuit board when the plastic layer 522 is formed, and a second thickness H ₂ at a region other than the land M (non-joining region) And the first thickness H _{1 is} greater than the second thickness H ₂ . The first thickness H ₁ can be between about 0.5 microns and 15 microns, and the second thickness H ₂ can be between about 0.5 microns and about 10 microns. This step can be carried out by printing, lithography, and spraying. Next, other elements are formed conformally on the partially thickened plastic layer 522. By thickening the thickness of the carrier layer 520 at the joint region M, when the substrate is peeled off, the stress applied to the touch structure of the joint region M can be alleviated, thereby enhancing the stability of the joint region M.

In the foregoing embodiment of the present invention, the sensing electrodes may be other aspects in addition to the strip structure shown in Fig. 3A. The sensing electrode 332 shown in the first embodiment is taken as an example to describe another sensing electrode. Referring to FIGS. 6A-6C, the sensing electrode 332 includes a plurality of first electrode blocks 332a arranged along the first direction. a plurality of first wires 332c connecting adjacent first electrode blocks 332a, and a plurality of second electrode blocks 332b arranged in a second direction, each of the second electrode blocks 332b being distributed on both sides of the first wire 332c. Preferably, the first direction and the second direction are perpendicular to each other. In the present embodiment, the auxiliary electrode 336 is simultaneously formed when the sensing electrode 332 is formed. In another embodiment, the auxiliary wires 334 may also be formed simultaneously. Other characteristics of the sensing electrode 332 and the auxiliary electrode 336 are the same as those of the previous embodiment, and are not described herein again.

As shown in FIG. 6B, after the sensing electrode 332 and the auxiliary electrode 336 of FIG. 6A are formed, the insulating block P is further formed on each of the first wires 332c. The insulating block P may be made of an insulating material such as an epoxy resin.

As shown in FIG. 6C, after the insulating block P shown in FIG. 6B is formed, the second wires 333 connecting the adjacent second electrode blocks 332b are further formed on the respective insulating blocks P, and the signal wires 340 are formed. The second wire 333 and the signal wire 340 may be formed at the same time or may be formed one after another. The second wire 333 may be of the same material as the signal wire 340, such as copper, aluminum, silver, gold, molybdenum aluminum molybdenum alloy, indium tin oxide (ITO), or a combination thereof. The second wire 333 may also be made of a material different from the signal wire 340.

By adopting the manufacturing method of the monolithic glass touch panel of the present invention, the problem of curl existing at the edge of the carrier layer when the substrate for carrying the substrate is peeled off in the prior art, and the problem that the components in the edge region are liable to fall off or be damaged may be alleviated. Improve the yield of a single glass trackpad.

While the invention has been described above in terms of several preferred embodiments, it is not intended to limit the scope of the present invention, and any one of ordinary skill in the art can make any changes without departing from the spirit and scope of the invention. And the scope of the present invention is defined by the scope of the appended claims.

400‧‧‧Single glass trackpad

420‧‧‧bearing layer

422‧‧‧ plastic layer

424‧‧‧buffer layer

432‧‧‧Sensor electrode

434‧‧‧Auxiliary wire

436‧‧‧Auxiliary electrode

440‧‧‧Signal wire

450‧‧‧Joint adhesive

451‧‧‧Adhesive

460‧‧‧ conductive adhesive

470‧‧‧ circuit board

480‧‧‧ cover

490‧‧‧Lighting layer

M‧‧‧ junction area

Claims (18)

A method for manufacturing a monolithic glass touch panel, comprising: S1: providing a substrate; S2: forming a carrier layer on the substrate; S3: forming a patterned conductive layer on the carrier layer, the patterned conductive The layer includes a sensing electrode, an auxiliary electrode is located outside the sensing electrode; S4: forming a plurality of signal wires electrically connected to the sensing electrode, and the signal wires are concentrated in at least one bonding region, the at least one bonding region is located The sensing electrode has at least one outer side; and S5: a cover is attached to the patterned conductive layer, and the substrate is removed from the carrying layer. The method for fabricating a monolithic glass touch panel according to claim 1, wherein in step S3, an auxiliary wire is simultaneously formed on the outside of the sensing electrode, and the signal wires are formed on the auxiliary wire. The method for fabricating a monolithic glass touch panel according to claim 1, wherein in step S2, forming the carrier layer comprises the steps of forming a plastic layer on the substrate, and forming a buffer layer on the plastic The steps on the layer. The method for fabricating a monolithic glass touch panel according to claim 1, wherein the step S3 can form the patterned conductive layer by screen printing or spraying. The method for fabricating a monolithic glass touch panel according to claim 1, further comprising the step of bonding a circuit board to the signal wires of the at least one bonding region. The manufacturer of the monolithic glass touch panel described in claim 5 of the patent application scope The method further includes the step of adding an adhesive to the gap between the circuit board and the carrier layer in the at least one bonding region. The method for fabricating a monolithic glass touch panel according to claim 1, further comprising the step of forming a light shielding layer on an edge of the cover. The method for fabricating a monolithic glass touch panel according to claim 1, wherein the substrate is removed by solution soaking, heat treatment, cold treatment, external force stripping or a combination thereof. The method of manufacturing the monolithic glass touch panel of claim 1, wherein the sensing electrode comprises: a plurality of first electrode blocks arranged along a first direction, the plurality of connecting adjacent ones of the first a first wire of the electrode block, a plurality of second electrode blocks arranged along a second direction, each of the second electrode blocks being distributed on two sides of the first wires, and each of the first wires is formed with an insulating block, and each Forming, on the insulating block, a second wire connecting adjacent second electrode blocks; wherein the first electrode block, the first wire, the second electrode block and the auxiliary electrode are formed in the same step, and the second wire is These signal wires are formed in the same step. A monolithic glass touch panel comprises: a cover plate; a carrier layer formed on the carrier layer: a patterned conductive layer comprising a sensing electrode and an auxiliary electrode on the outside of the sensing electrode; a wire electrically connected to the sensing electrode, wherein the signal wires are concentrated in the at least one bonding region, and the at least one bonding region is located on at least one outer side of the sensing electrode; and a bonding glue is disposed on the cover And the carrier layer for engaging the cover The board and the carrier layer. The monolithic glass touch panel of claim 10, wherein the sensing electrode further comprises an auxiliary wire, and the signal wires are formed on the auxiliary wire. The monolithic glass trackpad of claim 10, wherein the carrier layer comprises a plastic layer and a buffer layer, and the patterned conductive layer is formed on the buffer layer. The monolithic glass touch panel of claim 12, wherein the plastic layer is made of polyimide (PI), polypropylene (PP), polystyrene (PS), acrylonitrile-butyl Aceene-styrene resin (ABS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polycarbonate (PC), polyethylene (PE), polymethyl methacrylate (PMMA) , polytetrafluoroethylene (PTFE), or a combination of the foregoing. The monolithic glass trackpad of claim 12, wherein the buffer layer is made of ruthenium oxide. The monolithic glass trackpad of claim 12, wherein the buffer layer is an adhesion promoter comprising a functional group of an organophilic material and a functional group of an affinity material. The monolithic glass trackpad of claim 10, wherein the cover is formed with a light shielding layer at an edge thereof. The monolithic glass trackpad of claim 10, wherein the carrier layer is further formed with a circuit board electrically connected to the signal wires of the at least one junction region. The single-chip glass touch panel of claim 17, wherein An adhesive is formed in the gap between the circuit board and the carrier layer in the at least one bonding region.