TW594320B - Manufacturing method and structure of copper lines for a liquid crystal panel - Google Patents

Abstract

In those conventional arts, for large size liquid crystal display, the process of copper damascene interconnect has some problems of forming a not uniform copper seed layer and forming holes during electrical plating due to the electrical plating area being too large to electroplate uniformly. In this invention, it employs a Cu tape to directly paste onto a substrate to replace forming a copper seed layer and electrical plating. Hence, the invention avoids the problem of not uniform and forming hole in those conventional arts and so the copper line can be applied to the large size liquid crystal display.

Description

594320 V. Description of the invention (1) 1. [Technical field to which the invention belongs] The present invention relates to a method and structure for forming a lead of a liquid crystal panel, and more particularly to a method for forming a copper lead of a liquid crystal panel using a copper tape and structure. 2. [Previous technology] Liquid crystal displays have millions of thin film transistors. Through these thin film transistors, the arrangement of the liquid crystal corresponding to each thin film transistor can be controlled, thus determining the brightness of the pixels corresponding to each thin film transistor. The image is displayed. Each thin film transistor is connected to two wires, one is the gate line, and the other is the data line. The gate line is used to control the switching of the thin film transistor, so that the thin film transistor is turned on at a specific time and receives image data. The data line is the data used to transmit the image. The electrical response of the wires connected to these thin film transistors is extremely related to the resolution and response rate of the liquid crystal display. Most of the guide Jin Yue # 's and: W Jia he. When the interstitial center is lower than its line, the liquid crystal with low valence aluminum surface of the low-ply platen and the transduction crystal of gold is shown. The one with the liquid crystal valence aluminum surface or the crystal cross array I forming aluminum liquid moment is the moving Is. Maybe the master J1 is the size of Lai C due to the current development trend of aluminum-type LCDs. Traditionally, the basic material of large-size TFT-LCD panel size 20-inch wires is mainly electrical. Generally, a double-layered metal

594320

3 Γ ί 5 large-size LCD monitors have higher resolutions and faster lines (i TVs ii ii are LCD TVs), under the requirements of traditional Shao guide materials, electricity can not break the bottleneck situation Therefore, it is necessary to find new wires / to achieve the requirements of higher resolution and faster response rate. Two = i In the semiconductor integrated circuit industry, generally, the conductive wire is used to replace the boat wire to solve the problem of the conductivity bottleneck of the aluminum wire. Because steel does not have a suitable etching solution, copper It is quite difficult to make the wire too privately. First, as shown in the first figure, a groove 20 is formed on a substrate 10. Then, as shown in FIG. 2A, a thin and continuous copper seed layer 30 'is formed on the surface of the substrate 10 to improve the adhesion of the copper wire and promote the copper plating process. Grow. The copper seed layer 30 must also cover the surface of the groove 20 at the same time, so the copper seed layer 30 can promote the copper crystal growth during electroplating along the groove 20 structure, and the copper seed layer 30 must also It is thin, uniform and continuous so that no voids are created when filling copper. However, when there is a concern about leakage of copper due to diffusion to other structural layers, a barrier layer 40 must be added, as shown in Figure B, to prevent copper from entering the other layer structure by diffusion. Leakage can also prevent copper and silicon from reacting. Therefore, before forming the copper seed layer 30, it is sometimes necessary to first form a barrier layer 40 to prevent leakage problems. Next, the copper is electroplated by applying a power source to the copper plating layer 50 on the copper seed layer 30, so that the copper plating film 50 can continuously, smoothly and well cover the copper seed layer 30. Above '

594320 V. Description of the invention (3) Fill the groove 20 without any voids or defects, as shown in the third figure (the barrier layer 40 is not shown). Finally, a step of chemical mechanical polishing is performed, the copper metal on the substrate 10 other than the groove 20 is ground to the surface of the substrate 10, and only the copper metal filled in the groove 20 is left, such as the fourth As shown. In this way, the formation of the copper wire is completed. However, the above-mentioned copper wire manufacturing method is not applicable to the formation of copper wires for TFT-LCD active matrix liquid crystal display. The main reason is the size of the liquid crystal panel. Compared with the 12-inch wafers in the semiconductor industry, the area is still too large. Therefore, in the formation of the copper seed layer 30, it is difficult to control the thickness uniformity within the range, and it is easy to cause voids. Or, in the electroplating process, the control of the copper deposition rate must be more precise, so that the deposition rate in each area can be approximately the same. However, the difficulty of these problems will increase as the size increases. Therefore, for large-size panels, these problems are difficult to overcome. III. [Summary of the Invention] In view of the above-mentioned background of the invention, the manufacturing process of copper wires with conventional techniques has problems with the uniformity of the seed layer and the uniformity of plating during the formation of large-area copper wires. The main purpose of the present invention is to provide a new copper wire manufacturing process to avoid the problem of uniformity of the seed layer in the formation of large-area copper wires.

594320 V. Description of the invention (4) Another object of the present invention is to use the method of forming the copper wire of the present invention to avoid problems in the formation of large-area copper wires and the uniformity of plating. Yet another object of the present invention is to use a method of directly attaching a copper tape to a substrate, which can replace the seed layer and electroplating steps, reduce process steps, and reduce process costs. Yet another object of the present invention is that a copper wire formed by a copper tape can effectively avoid voids and defects and improve the uniformity of the formed copper wire. Another object of the present invention is to replace the aluminum wires with copper wires to reduce the RC delay time of the wires of the liquid crystal panel. According to the above-mentioned purpose, the present invention discloses a structure of a copper wire of a liquid crystal panel. The structure of the copper wire of the liquid crystal panel includes a substrate, a surface of which has a plurality of trenches; and a plurality of copper wires, the plurality of copper wires are attached to the substrate with a copper tape, and Chemical mechanical polishing is performed to form the copper tape completely outside the plurality of trenches. Furthermore, the present invention also discloses a method for forming a copper wire of a liquid crystal panel. The forming method of the present invention includes forming a plurality of trenches on a substrate; attaching a copper tape to the substrate and the plurality of trenches; and performing chemical mechanical polishing so that the copper tape is located outside the plurality of trenches. unit

594320 Fifth, the description of the invention (5) is completely removed. Because the thickness difference of the copper tape itself is very small, and the problem of voids or defects is easier to control than the method of forming a seed layer and filling the groove by electroplating in the conventional technique, it can avoid the problem in the conventional technique. Problems such as unevenness or voids. In addition, the number of copper wire manufacturing steps is less than that of conventional techniques, which can reduce manufacturing costs. Between the substrate and the copper tape, different structural layers can be formed first to meet the requirements of different processes. In addition, replacing copper wires with copper wires can reduce the RC delay time of the liquid crystal panel wires, so that the resolution and response rate of large-size liquid crystal panels are not limited by the conductive bottleneck of aluminum. 4. [Embodiments] Some embodiments of the present invention will be described in detail as follows. However, in addition to the detailed description, the present invention can also be widely implemented in other embodiments, and the scope of the present invention is not limited, which is subject to the scope of subsequent patents. Each ruler is within the gate, showing the picture and drawing it, and the full Ming and the finished inch are not the same as the ruler, but some solutions are necessary to understand the details and the description of the ruler. Qing Qizhang even more boast. The confession of the confession is simply endless, and it is more demanding than the phase-separation diagram shown.

Page 9 594320 V. Description of the Invention (6) A plurality of grooves 1 2 0 are formed on 1 1 0. The method for forming the groove 120 is: coating a photoresist on the substrate 110, and then exposing the photoresist with a photomask to develop the photoresist to remove the photoresist above the area of the groove 120. Then, using the developed photoresist as a mask, the substrate 110 is etched to form a groove 120. Generally, the substrate 1 10 is etched by a wet etching method. A preferred etching solution may be sodium hydroxide (NaOH), hydrofluoric acid (HF), or a mixed solution of hydrofluoric acid and ammonium fluoride (NH4F). Then, as shown in the sixth figure, a copper tape 160 is attached above the groove 120, and the groove 120 is filled up without problems such as voids. In order to ensure that the copper tape 160 can easily and surely fill the groove 120 and completely adhere to the substrate 110, the copper tape 160 can be subjected to high temperature, high pressure, or at the same time, to strengthen the copper tape 160 and the groove. 120 degree of adhesion. Finally, the substrate 110 on which the copper tape 160 has been attached is chemically and mechanically polished to the surface of the substrate 110, and copper other than the groove 120 is removed, as shown in the seventh figure, and the groove 1 2 0 is filled. The copper part is the copper wire. The present invention is applicable to any substrate, especially a large-sized substrate, such as a large-sized liquid crystal panel. In addition, the copper wire may be formed on other structural layers, and is not limited to being formed only on the glass substrate of the liquid crystal panel. For example, copper wires can also be formed on a silicon nitride (S i Nx) layer. Silicon nitride has a relatively low melting point, making it suitable for use on glass-based liquid crystal panels.

Page 10 594320 V. Description of the invention (7) Another note Γι 'hair 11 This board is based on the fact that in the case of Shi Shijia, for example, the first layer of silicon silicide is formed first, and the silicon is shown in the figure. After that, the shape of the layer of silicon silicide is blocked by 12 light grooves, and the coating is 70% of the number on the back. The light is exposed to the square light, and then it is recessed into 20 hoods. ， 2 shadow grooves are concave after engraving with a shadow-like light. Use the masterpiece to shape and then to carve. , # 刻刻 的 photoetching 70 rows 1 罾 Fang Jin Jlo silicon J: 7 layer 1 G layer nitrogen G silicon 12 rows into the groove nitrogen concave recession shown in the figure 12 So the 12 grooves are filled as shown in the nine recesses, After the integration, then the rectangular copper tape will be used to produce holes without holes in the hollow. It is required to fill the gaps with gaps. 6 is guaranteed to be 6-in-1 with dense copper and complete copper. Ο 12 high grooves are filled with concave filling. It is true and easy to hold the 6 11 taped copper to the grooved recess and ο 6 11 taped copper. High temperature, high temperature, high temperature, high density, high density, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high temperature, high density Nitrogen is only 60 on 7 sides with copper. There are 17 cladding layers with silicon, and after nitrogen, the most conductive copper is the copper of the branch. 2 11 The groove is completely filled and the tenth figure is shown as f ο In addition to the wire scattered copper into the shape due to the or will be subject to copper will be attached to the strong, strong, add a good question layer enough to wait for the electrical layer ri leakage layer to form a groove caused by the shape of the middle i ο Base 1 —Ji 1 and 纟 罾 ο / Base 6te sound glue into 6 copper tape with square glue

Page 11 594320 V. Description of the invention (8) A barrier layer prevents copper diffusion. The connection layer or the barrier layer is formed by first forming the connection layer or the barrier layer on the groove and the substrate, and then attaching the copper tape 160 to the connection layer or the barrier layer. Therefore, in the above-mentioned preferred embodiments, a connection layer or a barrier layer can be formed according to the formation method. The requirement of the connection layer is that it must have good adhesion to the substrate 110 or copper tape 160. The barrier layer is required to be able to prevent the diffusion of copper and have good adhesion to the substrate 110 and the copper tape 160. The method and structure for forming copper wires of a liquid crystal panel of the present invention are suitable for forming wires in a non-display area of a liquid crystal panel, so as to prevent the copper wires from shielding or reflecting the light source emitted from the light source module of the liquid crystal panel in the display area. Therefore, the present invention is also applicable to a liquid crystal panel in which a chip is packaged on a glass substrate (c h i ρ ο n g 1 a s s, C 0 G). If the array part of the wires in the display area is properly processed (for example, an anti-reflection layer is formed around the wires to reduce light reflection), the wires of the array can also be formed into copper wires according to the present invention. In summary, the present invention discloses a method and structure for forming a copper wire of a liquid crystal panel. The present invention uses a method of attaching a copper tape to replace the conventional method of forming a seed layer and then electroplating a full groove. The uniformity of the thickness of the copper tape is very good, and the problem of voids or defects is less likely to occur than in the conventional technique of forming a seed layer and then filling the groove by electroplating, so it can be avoided Problems such as unevenness or voids. Moreover, the manufacturing process of copper wires is less than that of conventional techniques, which can reduce

Page 12 594320 V. Description of the invention (9) Process cost. Between the substrate and the copper tape, different structural layers may be formed first to meet the requirements of different processes. Moreover, replacing copper wires with aluminum wires can reduce the RC delay time of the liquid crystal panel wires, so that the resolution and response rate of large-sized liquid crystal panels are not limited by the conductive bottleneck of aluminum. The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of patent application of the present invention; all other equivalent changes or modifications made without departing from the spirit disclosed by the present invention shall be included in the following The scope of patent application.

Page 594320 Schematic illustration of the first picture is a schematic diagram of the steps of forming grooves on the substrate in the copper process of the conventional art, and the second picture A is formed of the substrate and the grooves in the copper process of the conventional art. The steps of the copper seed layer are not intended. Figure 2B is a schematic diagram of the steps of forming a barrier layer and a copper seed layer on the substrate and the groove in the copper process of the conventional art;

The third picture is a schematic diagram of the steps of performing copper plating and the surface of the substrate in the copper process of the conventional technique; the fourth picture is the chemical mechanical grinding in the conventional copper process of the technique to remove the non-groove copper The fifth diagram is a schematic diagram of a step of forming a groove on a substrate in a preferred embodiment of the present invention. The sixth diagram is a schematic diagram of a substrate and a recess in a preferred embodiment of the present invention. Schematic diagram of the steps of attaching copper tape to the groove;

The seventh diagram is a schematic diagram of a step of performing chemical mechanical polishing to remove copper on non-grooves to form copper wires in a preferred embodiment of the present invention;

Page 594320 Brief Description of the Drawings The eighth diagram is a schematic diagram of a step of forming a silicon nitride layer on a substrate and forming a groove on the silicon nitride layer in another preferred embodiment of the present invention. The ninth diagram is In another preferred embodiment of the present invention, a schematic diagram of a step of attaching a copper tape on a silicon nitride layer and a groove; and the tenth diagram is a chemical mechanical polishing in another preferred embodiment of the present invention to Schematic diagram of the steps to remove copper from the grooves to form copper wires. Representative symbols of the main parts: 10 substrates 20 grooves 30 copper seed layer 4 0 barrier layer 50 copper plating film 110 substrate 120 groove 160 copper tape 170 silicon nitride layer

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Claims (1)

594320 6. Application scope 1. A method for forming a copper wire of a liquid crystal panel, comprising the steps of: forming a plurality of trenches on a substrate; attaching a copper tape on the substrate and the plurality of trenches; and performing chemistry Mechanical grinding completely removes the portion of the copper tape outside the plurality of trenches. 2. The method for forming a copper wire of a liquid crystal panel according to item 1 of the patent application scope further comprises forming a barrier layer on the plurality of trenches, between the substrate and the copper tape. 3. For the method for forming a copper wire of a liquid crystal panel according to item 1 of the application, the substrate is a glass substrate. 4. For the method for forming the copper wires of the liquid crystal panel in the first scope of the patent application, the plurality of trenches of the substrate are etched with sodium hydroxide. 5 · If the method for forming copper wires of a liquid crystal panel according to item 1 of the patent application, the plurality of trenches of the substrate are etched with hydrofluoric acid. 6. For the method for forming a copper wire of a liquid crystal panel according to item 1 of the scope of patent application, the plurality of trenches of the substrate are formed by a mixture of hydrofluoric acid and ammonium fluoride. 7. The formation method of the copper wires of the liquid crystal panel such as the scope of the patent application No. 1 Page 16 594320 VI. Patent Application Law, the plurality of trenches are formed in the non-display area around the liquid crystal panel. 8. In the method for forming a copper wire of a liquid crystal panel according to item 1 of the patent application scope, the copper tape is attached to the substrate by heating. 9. In the method for forming a copper wire of a liquid crystal panel according to item 1 of the scope of patent application, the copper tape is attached to the substrate under pressure. 10. —A method for forming a copper wire of a liquid crystal panel, including: Forming a silicon nitride layer on a substrate; forming a plurality of trenches on the silicon nitride layer; attaching a copper tape on the plurality of trenches and the silicon nitride layer; and performing chemical mechanical polishing so that The portion of the copper tape outside the plurality of trenches is completely removed. 11. The method for forming a copper wire of a liquid crystal panel according to item 10 of the application, further comprising forming a barrier layer on the plurality of trenches and the silicon nitride layer, the plurality of trenches and the copper tape. between. 12. For a method for forming a copper wire of a liquid crystal panel in the scope of application for item 10, the plurality of trenches are etched by a wet etching method. 1 3. The formation method of the copper wire of the liquid crystal panel according to the scope of application for patent No. 10 Page 17 594320 VI. Patent Application Law, the plurality of trenches are formed in the non-display area around the liquid crystal panel. 14. For a method for forming a copper wire of a liquid crystal panel in the scope of application for item 10, the copper tape is attached to the substrate by heating. 15. For a method for forming a copper wire of a liquid crystal panel in the scope of application for patent item 10, the copper tape is attached to the substrate under pressure. 16. —The structure of a copper wire of a liquid crystal panel, including: A substrate having a plurality of trenches on one surface of the substrate; and a plurality of copper conductors, the plurality of copper conductors are attached to the substrate with a copper tape, and then subjected to chemical mechanical grinding to make the copper tape The portion outside the plurality of trenches is completely removed and formed. 17. For the structure of the copper wires of the liquid crystal panel of the 16th patent application range, the substrate is a glass substrate. 18. For the structure of the copper wire of the liquid crystal panel of item 16 in the scope of patent application, the material of the substrate is oxidized stone. 19. For the structure of the copper wires of the liquid crystal panel in the 16th area of the patent application, the plurality of trenches are etched by a wet etching method. Page 18 594320 VI. Scope of patent application 20. For the structure of the copper wire of the liquid crystal panel of item 16 of the patent application scope, the plurality of trenches are formed in the non-display area around the liquid crystal panel. 21. For the structure of the copper wire of the liquid crystal panel of item 16 in the scope of patent application, the copper tape is attached to the substrate after heating. 22. For the structure of the copper wires of the liquid crystal panel of the 16th patent application range, the copper tape is attached to the substrate under pressure. 23. For example, the structure of the copper wire of the liquid crystal panel of item 16 of the patent application scope further includes a barrier layer formed on the plurality of trenches, between the substrate and the copper tape. Page 19