TWI791303B - Manufacturing method of carrier tape metal circuit and carrier tape - Google Patents

Abstract

The invention discloses a manufacturing method of a carrier metal circuit, which includes the following steps: S00: sputtering metal atoms on the upper surface of a substrate film to form a seed layer; S10: processing a connecting layer on the upper surface of the seed layer to connect the surface of the layer is treated to increase the surface roughness of the connection layer; S20: uniformly coat a layer of photoresist on the upper surface of the connection layer to form a photoresist layer; S30: sequentially expose and develop the photoresist layer, form trenches between the photoresist layers; S40: long copper processing is performed in the trenches between the photoresist layers to form metal lines; S50: wash away the photoresist layer; S60: perform nano-etching Process until the seed layer and the connection layer between the metal lines are completely etched; the connection layer is used to increase the connection strength between the seed layer and the photoresist layer, so as to avoid the photoresist falling off or offset.

Description

Manufacturing method of carrier tape metal circuit, carrier tape

The invention relates to the technical field of carrier tape processing, in particular to a method for manufacturing a metal circuit on a carrier tape and a carrier tape manufactured by using the method for manufacturing a metal circuit on a carrier tape.

FPC (Flexible Printed Circuit) refers to a flexible circuit board, which is a highly reliable and excellent flexible printed circuit board made of polyimide or polyester film as the base material. Referred to as soft board or FPC, it has the characteristics of high wiring density, light weight and thin thickness.

COF (Chip On Flex or Chip On Film) refers to chip-on-chip film, which is a soft film construction technology that fixes the driver IC on a flexible circuit board. Bonding technology, COF is a kind of FPC that requires high precision. COF usually needs to be exposed and developed during production, so photoresist will be used in large quantities. The existing process usually adds photoresist directly on the surface of the seed layer, and then proceeds to exposure and development. Due to the low connection strength between the photoresist and the seed layer, the photoresist is prone to fall off or misaligned during transportation and processing. The phenomenon of shifting causes the subsequent metal circuit to fail to meet the process requirements.

The present invention aims to solve at least one of the technical problems existing in the prior art.

Therefore, the present invention proposes a method for fabricating a metal circuit with a tape. The method for fabricating a metal circuit with a tape has the advantage that the photoresist is firmly connected and does not fall off or deviate during fabrication.

The method for manufacturing a metal circuit with a tape according to an embodiment of the present invention includes the following steps, S00: sputtering metal atoms on the upper surface of the substrate film to form a seed layer; S10: processing a connection layer on the upper surface of the seed layer, for The surface of the connection layer is treated to increase the surface roughness of the connection layer; S20: uniformly coat a layer of photoresist on the upper surface of the connection layer to form a photoresist layer; S30: sequentially expose and develop the photoresist layer , so that grooves are formed between the photoresist layers; S40: perform long copper treatment in the grooves between the photoresist layers to form metal lines; S50: wash away the photoresist layer; S60: conduct nanometer micro Etching until the seed layer and the connection layer between the metal lines are completely etched; the connection layer is used to increase the connection strength between the seed layer and the photoresist layer.

According to an embodiment of the present invention, wherein the seed layer includes a bottom layer and an upper layer, the bottom layer is made of one of tungsten, nickel, copper, vanadium, molybdenum, tin, zinc, cobalt, iron, titanium or an alloy thereof , the thickness of the bottom layer is 10 nm to 30 nm, the upper layer is made of copper, gold, silver or an alloy thereof, the thickness of the upper layer is 50 nm to 100 nm, the S00 Specifically, the bottom layer and the top layer are uniformly sputtered successively on the upper surface of the substrate film by using a vacuum magnetron sputtering machine.

According to an embodiment of the present invention, wherein, in S10, the connection layer is a metal mixture containing aluminum, and the thickness of the connection layer is 50 nm to 150 nm.

According to an embodiment of the present invention, wherein, in the S10, the aluminum on the surface of the connection layer is washed away with a strong alkali solution, thereby improving the surface roughness of the connection layer.

According to an embodiment of the present invention, wherein the photoresist layer is a positive resist, the exposure and development process is as follows: firstly make a light-shielding film, open a light-transmitting hole on the light-shielding film, and transmit light on the light-shielding film The part is consistent with the shape of the metal circuit, the light-transmitting film is placed on the photoresist layer, and then the photoresist layer is exposed by ultraviolet light through the light-transmitting hole, so that the photoresist layer in the exposed area undergoes chemical reaction. Should; use developer solution to wash away the photoresist layer in the exposed area, so that the photoresist layer on the unexposed area can be retained.

According to an embodiment of the present invention, wherein the photoresist layer is a negative-tone adhesive, the exposure and development process is as follows: firstly make a light-shielding film, and open a light-transmitting hole on the light-shielding film, so that the light-shielding film is not transparent. The part of the light is consistent with the shape of the metal circuit. The light-transmitting film is placed on the photoresist layer, and then the photoresist layer is exposed by ultraviolet light through the light-transmitting hole, so that the photoresist layer in the exposed area is chemically Reaction; using a developer to wash off the photoresist layer in the unexposed area, so that the photoresist layer on the exposed area is retained.

According to an embodiment of the present invention, wherein, the operation of growing copper is as follows: connect the substrate film to the cathode, and simultaneously immerse the upper surface of the substrate film in a solution filled with copper ions, so that the copper ions are deposited between the photoresist layer start to deposit and form metal lines in the trenches between them, and the thickness of the metal lines is 8 microns to 12 microns.

According to an embodiment of the present invention, wherein, in S60, the thickness of the nano-etching is the sum of the thickness of the seed layer and the thickness of the connection layer.

According to an embodiment of the present invention, wherein, the connection layer is a mixture of nickel and aluminum.

According to an embodiment of the present invention, wherein the connection layer is processed by sputtering a target material, the target material is made of aluminum plates and other metal plates interlaced or made of a mixture of aluminum and other metals.

According to an embodiment of the present invention, after the step S60, a tin layer and an anti-oxidation paint layer need to be successively coated on the surface of the metal circuit.

According to an embodiment of the present invention, a carrier tape manufactured by any one of the methods for manufacturing a carrier metal circuit described above, the carrier tape includes: a base film; a seed layer, the seed layer is arranged on the base film The upper surface of the connection layer; the connection layer, the connection layer is arranged on the upper surface of the seed layer; the metal circuit, the metal circuit is arranged on the upper surface of the connection layer; the tin layer, the tin layer is coated on the seed layer, the The outer surface after the stacked layer and the metal circuit; the anti-oxidation paint layer, the anti-oxidation paint layer is coated on the outer surface of the tin layer and the base film; the upper surface of the connection layer has A concave-convex structure, the connection layer has a hole structure inside, and a part of the metal circuit enters the concave-convex structure and the hole structure.

The beneficial effect of the present invention is that the process of the present invention is simple and easy to implement. By processing the connection layer on the seed layer and treating the surface of the connection layer, the roughness of the connection layer surface can be improved, thereby improving the photoresist layer. The connection strength with the connection layer prevents the photoresist from falling off or shifting during the process of making the metal circuit, so that the metal circuit can grow stably in the groove between another part of the photoresist layer, and the final produced The metal line size is also more uniform, and the yield of the carrier tape is higher.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description, claims and drawings.

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

1: Substrate film

2: Seed layer

3: Connection layer

4: Photoresist layer

5: Metal wiring

6: tin layer

7: Anti-oxidation paint layer

Fig. 1 is a schematic flow chart of a method for manufacturing a metal circuit with a carrier according to an embodiment of the present invention; Fig. 2 is a schematic diagram of a photoresist layer in the process of manufacturing a method for a metal circuit with a carrier according to an embodiment of the present invention; Fig. 3 is a schematic diagram of a photoresist layer using The schematic diagram of the photoresist layer in the manufacturing process of the manufacturing method of the carrier metal circuit according to the embodiment of the present invention; FIG. 4 is a schematic diagram of the photoresist layer in the manufacturing process of the prior art; Fig. 5 is a schematic diagram of a photoresist layer in the manufacturing process using the prior art.

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are only used for explaining the present invention, and should not be construed as limiting the present invention.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial" , "radial", "circumferential" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or Elements must have certain orientations, be constructed and operate in certain orientations, and therefore should not be construed as limitations on the invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those with ordinary knowledge in the art can understand the specific meanings of the above terms in the present invention in specific situations.

The method for fabricating the tape-carrying metal circuit according to the embodiment of the present invention will be specifically described below with reference to the drawings.

As shown in FIGS. 1 to 5 , the method for manufacturing a metal circuit with a carrier tape according to an embodiment of the present invention includes the following steps, S00: sputtering metal atoms on the upper surface of the substrate film 1 to form a seed layer 2; S10: Process the connection layer 3 on the upper surface of the seed layer 2, and process the surface of the connection layer 3 to improve the surface roughness of the connection layer 3; Adhesive layer 4; S30: sequentially perform exposure and development on the photoresist layer 4 to form grooves between the photoresist layers 4; S40: perform copper growth treatment in the grooves between the photoresist layers 4, To form the metal circuit 5; S50: wash away the photoresist layer 4; S60: perform nanometer micro-etching treatment until the seed layer 2 and the connection layer 3 between the metal circuit 5 are completely etched; the connection layer 3 is used to increase the seed The connection strength between layer 2 and photoresist layer 4.

According to one embodiment of the present invention, the seed layer 2 includes a bottom layer and an upper layer, the bottom layer is made of one of tungsten, nickel, copper, vanadium, molybdenum, tin, zinc, cobalt, iron, titanium or an alloy thereof, and the thickness of the bottom layer is 10 nanometers to 30 nanometers, the upper layer is made of copper, gold, silver or one of their alloys, the thickness of the upper layer is 50 nanometers to 100 nanometers, S00 is specifically: using a vacuum magnetron sputtering machine on the substrate The upper surface of the film 1 is uniformly sputtered successively with the bottom layer and the upper layer. Since the base film 1 itself does not have the ability to attach metal, if the metal circuit 5 is directly made on the base film 1, it will be easier to fall off. Compared with the upper layer, the bottom layer can have better bonding strength with the base film 1, which can The effect of avoiding falling off is achieved, and the upper layer has better electrical conductivity, which facilitates the manufacture of the metal circuit 5 .

According to an embodiment of the present invention, in S10, the connection layer 3 is a metal mixture containing aluminum, and the thickness of the connection layer 3 is 50 nm to 150 nm. Further, in S10, the aluminum on the surface of the connection layer 3 is washed away with a strong alkali solution, thereby increasing the surface roughness of the connection layer 3 . That is to say, if the connection layer 3 is set as a metal mixture containing aluminum, when the aluminum on the surface of the connection layer 3 is washed away by a strong alkali solution, it will not damage the other metals of the seed layer 2, the base film 1 and the connection layer 3. cause damage, while the surface of the connection layer 3 is damaged by strong alkali due to aluminum The surface roughness is improved, and the bonding strength between the connection layer 3 and the photoresist layer 4 is greatly improved.

According to one embodiment of the present invention, the photoresist layer 4 is a positive resist, and the exposure and development process is as follows: first make a light-shielding film, open a light-transmitting hole on the light-shielding film, and the light-transmitting part on the light-shielding film and the metal circuit The shapes of 5 are consistent, the light-transmitting film is placed on the photoresist layer 4, and then the photoresist layer 4 is exposed by ultraviolet light through the light-transmitting hole, so that the photoresist layer 4 in the exposed area undergoes a chemical reaction; The photoresist layer 4 in the exposed area is washed away with a developing solution, so that the photoresist layer 4 in the unexposed area remains.

According to another embodiment of the present invention, the photoresist layer 4 is a negative resist, and the exposure and development process is as follows: first make a light-shielding film, open a light-transmitting hole on the light-shielding film, and the part of the light-shielding film that is not transparent Consistent with the shape of the metal circuit 5, the light-transmitting film is placed on the photoresist layer 4, and then the photoresist layer 4 is exposed to ultraviolet light through the light-transmitting hole, so that the photoresist layer 4 in the exposed area Chemical reaction: using a developer to wash away the photoresist layer 4 in the unexposed area, so that the photoresist layer 4 in the exposed area remains.

According to one embodiment of the present invention, the operation of growing copper is as follows: connect the substrate film 1 to the cathode, and simultaneously immerse the upper surface of the substrate film 1 in a solution full of copper ions, so that the copper ions are deposited on the photoresist layer 4 Deposit and form a metal line 5 in the trench between them, the thickness of the metal line 5 is 8 microns to 12 microns.

According to an embodiment of the present invention, in S60 , the thickness of the nano-etching is the sum of the thickness of the seed layer 2 and the thickness of the connection layer 3 . During etching, the seed layer 2 and the connection layer 3 in other areas between the metal circuits 5 on the upper surface of the substrate film 1 are all etched to avoid short circuits between the circuits.

According to an embodiment of the present invention, the connection layer 3 is a mixture of nickel and aluminum. On the one hand, nickel has better bonding strength with the substrate film 1, and on the other hand, the cost of using nickel metal is relatively low.

According to an embodiment of the present invention, the connecting layer 3 is processed by sputtering with a target material, and the target material is made of aluminum plates and other metal plates interlaced or made of a mixture of aluminum and other metals. That is to say, when the connection layer 3 is sputtered, the target used can be made of aluminum plates and other metal plates interlaced, or a mixture of aluminum and other metals, which can be selected according to the actual cost of use.

According to an embodiment of the present invention, after S60, a tin layer 6 and an anti-oxidation paint layer 7 need to be coated successively on the surface of the metal circuit 5 . The tin layer 6 and the anti-oxidation paint layer 7 can improve the oxidation resistance of the carrier tape, thereby improving the service life. On the other hand, the tin layer 6 can be melted when the metal circuit 5 is connected to the chip pin, thereby facilitating the connection between the chip and the metal circuit 5. connected.

The present invention also provides a carrier tape manufactured by the above-mentioned manufacturing method of the carrier tape metal circuit, the carrier tape comprising: a base film 1, a seed layer 2, a connection layer 3, a metal circuit 5, a tin layer 6 and an oxidation-resistant paint layer 7, The seed layer 2 is arranged on the upper surface of the base film 1; the connection layer 3 is arranged on the upper surface of the seed layer 2; the metal circuit 5 is arranged on the upper surface of the connection layer 3; the tin layer 6 is coated on the seed layer 2, the connection layer 3 The outer surface after stacking with the metal circuit 5; the anti-oxidation paint layer 7 is coated on the outer surface of the tin layer 6 and the base film 1; the upper surface of the connecting layer 3 has a concave-convex structure, and the inside of the connecting layer 3 has a hole structure, and the metal A part of the line 5 enters the concave-convex structure and the hole structure. That is to say, after the aluminum is washed away, the connection layer 3 forms a concave-convex structure and a hole structure, which can increase the connection strength with the photoresist layer 4 on the one hand, and interpenetrate with the metal circuit 5 on the other hand, thereby improving the connection with the photoresist layer 4. The connection strength of the metal line 5.

Example 1

According to the manufacturing method of the above-mentioned carrier metal circuit, the composition of the connecting layer 3 is nickel and copper. After the step S40 is completed, the microscope is used for magnified observation. It can be seen from Fig. 2 and Fig. 3 that the unexposed area Another part of the photoresist layer 4 still maintains a relatively stable structure.

Comparative example 1

Maintain the same process parameters as in Example 1, and start production according to the production method without adding the connection layer 3. After the exposure and development operations, use a microscope for magnified observation. From Figure 4 and Figure 4 5, it can be seen that another part of the photoresist layer 4 on the unexposed area is bent and deformed or partially peeled off.

From the comparative results of Example 1 and Comparative Example 1, it can be seen that the method for making a metal circuit with a carrier tape of the present application can significantly improve the connection strength between the photoresist layer 4 and the seed layer 2. The process of the present invention is simple and easy to implement. The connection layer 3 is processed on the seed layer 2, and the surface of the connection layer 3 is treated to improve the roughness of the surface of the connection layer 3, thereby improving the connection strength between the photoresist layer 4 and the connection layer 3, and avoiding the The photoresist falls off or shifts during the process of making the metal circuit 5, so that the metal circuit 5 can grow stably in the groove between the other part of the photoresist layer 4, and the finally produced metal circuit 5 is more uniform in size , the yield rate of the carrier tape is higher.

In the description of this specification, references to the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific examples," or "some examples" are intended to mean that the implementation A specific feature, structure, material, or characteristic described by an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.

1: Substrate film

2: Seed layer

3: Connection layer

4: Photoresist layer

5: Metal wiring

6: tin layer

7: Anti-oxidation paint layer

Claims (10)

A method for manufacturing a metal circuit with a tape, comprising the following steps: S00: sputtering metal atoms on the upper surface of a substrate film (1) to form a seed layer (2); S10: forming a seed layer (2) on the upper surface of the seed layer (2) Process the connection layer (3), and process the surface of the connection layer (3) to increase the surface roughness of the connection layer (3); S20: evenly coat a layer of photoresist on the upper surface of the connection layer (3), forming The photoresist layer (4); S30: performing exposure and development on the photoresist layer (4) sequentially, so that grooves are formed between the photoresist layers (4); S40: between the photoresist layers (4) Carry out long copper treatment in the groove between to form metal lines (5); S50: wash away the photoresist layer (4); S60: perform nanometer micro-etching treatment until the seed layer between the metal lines (5) (2) and the connection layer (3) are completely etched; wherein, the connection layer (3) is used to increase the connection strength between the seed layer (2) and the photoresist layer (4), the The seed layer (2) includes a bottom layer and an upper layer, the bottom layer is made of one of tungsten, nickel, copper, vanadium, molybdenum, tin, zinc, cobalt, iron, titanium or an alloy thereof, and the thickness of the bottom layer is 10 nanometers The thickness of the upper layer is from 50 nm to 100 nm, and the S00 is specifically: using vacuum magnetron sputtering A jet machine uniformly sputters a bottom layer and an upper layer successively on the upper surface of the substrate film (1), the connection layer (3) is a metal mixture containing aluminum, and the thickness of the connection layer (3) is 50 nm to 150 nm. The method for manufacturing a metal circuit with a tape according to claim 1, wherein in the step S10, the aluminum on the surface of the connection layer (3) is washed away with a strong alkali solution, thereby improving the surface roughness of the connection layer (3). The method for manufacturing a metal circuit with a carrier tape as described in claim 1, wherein the photoresist layer (4) is a positive resist, and the exposure and development process is as follows: firstly make a light-shielding film, on the light-shielding film Open a light-transmitting hole, and the light-transmitting part on the light-shielding film is consistent with the shape of the metal circuit (5). The adhesive layer (4) is subjected to exposure treatment, so that the photoresist layer (4) in the exposed area undergoes a chemical reaction; the photoresist layer (4) in the exposed area is washed away with a developing solution, so that the photoresist layer (4) in the unexposed area (4) is preserved. The method for manufacturing a metal circuit with a carrier tape as described in Claim 1, wherein the photoresist layer (4) is a negative resist, and the exposure and development process is as follows: firstly make a light-shielding film, on the light-shielding film Open a light-transmitting hole, and the opaque part on the light-shielding film is consistent with the shape of the metal circuit (5). The photoresist layer (4) is subjected to exposure treatment, so that the photoresist layer (4) in the exposed area undergoes a chemical reaction; the photoresist layer (4) in the unexposed area is washed away with a developing solution, so that the photoresist layer (4) in the exposed area Layer (4) is preserved. The manufacturing method of metal circuit with tape as claimed in claim item 1, wherein, the operation of long copper treatment is: connect the substrate film (1) to the cathode, and simultaneously immerse the upper surface of the substrate film (1) in a layer filled with copper ion solution, so that copper ions start to deposit in the grooves between the photoresist layers (4) and form metal lines (5), the thickness of the metal lines (5) is 8 microns to 12 microns. The method for manufacturing a metal circuit with a carrier tape according to claim 1, wherein, in S60, the thickness of the nanometer micro-etching is the sum of the thickness of the seed layer (2) and the thickness of the connection layer (3). The method for manufacturing a metal circuit with a carrier tape according to claim 1, wherein the connection layer (3) is a mixture of nickel and aluminum. The method for manufacturing a tape-carrying metal circuit as described in Claim 7, wherein the connection layer (3) is processed by sputtering a target material, and the target material is formed by interlaced splicing of aluminum plates and other metal plates or is made of Made of a mixture of aluminum and other metals. The method for manufacturing a metal circuit with a carrier tape as described in Claim 1, wherein, after said S60, it is also necessary to successively coat a layer of tin layer (6) and an anti-oxidation paint layer (7) on the surface of the metal circuit (5) . A carrier tape manufactured by the method for manufacturing a metal circuit of a carrier tape as described in any one of claim 1 to claim 9, wherein the carrier tape comprises: a base film (1); a seed layer (2) , the seed layer (2) is arranged on the upper surface of the base film (1); a connecting layer (3), the connecting layer (3) is arranged on the upper surface of the seed layer (2); a metal circuit (5 ), the metal circuit (5) is arranged on the upper surface of the connection layer (3); a tin layer (6), the tin layer (6) is coated on the seed layer (2), the connection layer (3) and The outer surface of the stacked metal circuit (5); an anti-oxidation paint layer (7), the anti-oxidation paint layer (7) is coated on the outer surface of the tin layer (6) and the substrate film (1); Wherein, the upper surface of the connection layer (3) has a concave-convex structure, the interior of the connection layer (3) has a hole structure, and a part of the metal circuit (5) enters the concave-convex structure and the hole structure.

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