JP2008235791A - Tape circuit board, semiconductor device, and production method of them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tape circuit board without limitation of a packaging direction of a semiconductor chip and an external substrate, allowing bonding with a narrow pitch semiconductor chip. <P>SOLUTION: The tape circuit board comprises a flexible insulating substrate 2a, and a conductor wiring 4a formed on the insulating substrate 2a. The conductor wiring 4a has a portion 5a with a triangular cross-sectional shape and a portion 6a with a rectangular cross-sectional shape. The portion 5a with a triangular cross-sectional shape of the conductor wiring 4a includes an inner lead part formed in a portion 3, formed so as to package a semiconductor chip of the conductor wiring 4a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a tape wiring substrate and a semiconductor device configured by providing conductor wiring on a flexible insulating base material, and a method for manufacturing the same.

  TCP (Tape Carrier Package) and COF (Chip On Film) are known as a type of package module using a tape wiring board. TCP and COF have a structure in which a semiconductor chip is mounted on a flexible insulating tape wiring substrate and the mounting portion is protected by sealing with resin. In TCP, a hole called a device hole is formed in a semiconductor chip mounting region, and a semiconductor chip is connected to a conductor wiring called an inner lead protruding into the device hole. The COF does not have a device hole, and a semiconductor chip is disposed on the tape wiring substrate.

  The tape wiring board has an insulating film base material and a large number of conductor wirings formed on the surface as main elements. Generally, polyimide is used as the film substrate, and copper is used as the conductor wiring. If necessary, a metal plating film and a solder resist layer which is an insulating resin are formed on the conductor wiring.

  The main use of TCP and COF is mounting a driver for driving a display panel such as a liquid crystal panel. In that case, the conductor wiring on the tape wiring board is divided into a first group that forms the output signal external terminals and a second group that forms the input signal external terminals. The element is mounted. Inner leads, which are connection ends with the semiconductor chip in the conductor wiring on the tape wiring substrate, are connected to electrode pads on the semiconductor element via protruding electrodes. An outer lead bonding portion (external connection terminal) forming an output signal external terminal in one group of conductor wirings is connected to a terminal of a glass panel or a mother substrate.

  An example of the tape wiring board as described above is described in Patent Document 1. Such a tape wiring board will be described with reference to FIG. FIG. 26 is a cross-sectional view of the semiconductor chip mounting portion of the tape wiring substrate.

  An electrode pad 104 is formed on the surface of the semiconductor chip 101. The tape base material 102 is a flexible and insulating tape, and a conductor wiring is formed on the tape base material 102. A plurality of inner leads 105 are formed at the tip of the conductor wiring. The inner lead 105 is connected to the protruding electrode 103 formed on the electrode pad 104. The conductor wiring formed on the tape base material 102 has the same shape and thickness from the inner lead 105 to the outer lead bonding, and a trapezoid in which the wider cross-sectional shape is connected to the tape base material 102. It is.

With this configuration, the conductor wiring can be stably connected to the glass panel or the mother substrate while ensuring the connectivity with the semiconductor chip.
JP-A-4-142048

  In the tape wiring substrate having the above configuration, the narrower conductor wiring is connected to the mounting surface of the semiconductor chip, and the wider one is connected to an external substrate such as a glass panel or a mother substrate to stabilize the connection. That is, the semiconductor chip and the external substrate are connected to the opposite side with respect to the conductor wiring. For this reason, the pitch of the conductor wiring is determined in accordance with the wider width of the trapezoidal conductor wiring, and there is a restriction that it is difficult to reduce the pitch of the conductor wiring.

  It is an object of the present invention to provide a tape wiring substrate that has no restriction on the mounting direction of the semiconductor chip and the external substrate with respect to the conductor wiring, and that facilitates bonding to the semiconductor chip having a narrow pitch.

  The tape wiring board of the present invention includes a flexible insulating base material and a conductor wiring formed on the insulating base material. In order to solve the above problem, the conductor wiring has a triangular cross section and a quadrangular section.

  In order to solve the above problems, the first method for producing a tape wiring board of the present invention includes a step of forming a photoresist on a base material having a conductor layer on a flexible insulating base material, and the photoresist. Forming an opening in the substrate, etching the conductor layer using the photoresist in which the opening is formed as a mask, forming a conductor wiring, and removing the photoresist. In the step of forming the portion, the opening is formed so that the mask width of the portion where the width of the conductor wiring is relatively narrow is narrowed with respect to the portion where the width of the conductor wiring is relatively wide, and the etching is performed In this step, etching is performed so that the cross-sectional shape of the portion where the width of the conductor wiring is relatively wide is a square, and the cross-sectional shape of the portion where the width of the conductor wiring is relatively narrow is a triangle.

  In order to solve the above problems, the second method for producing a tape wiring substrate of the present invention includes a step of forming a photoresist on a base material having a conductor layer on a flexible insulating base material, and the photoresist. A step of forming an opening in the substrate, a first etching step of etching the conductor layer using the photoresist having the opening formed as a mask, a step of removing the photoresist, and etching the conductor layer to form a conductor. A second etching step of forming a wiring, and in the step of forming the opening, a mask of a portion where the width of the conductor wiring is relatively narrow with respect to a portion where the width of the conductor wiring is relatively wide The opening is formed in the photoresist so that the width becomes narrower, and in the second etching step, the cross-sectional shape of the relatively wide portion of the conductor wiring is a quadrangle, and the conductor distribution Cross-sectional shape of the width is relatively narrow portion of etched so that the triangle.

  In order to solve the above problems, a third method for manufacturing a tape wiring substrate of the present invention includes a step of forming a photoresist on a base material having a conductor layer on a flexible insulating base material, and the photoresist. Forming an opening in the substrate, etching the conductor layer using the photoresist in which the opening is formed as a mask, removing a part of the photoresist, and a photo with the part removed Using the resist as a mask, a conductor wiring having a triangular cross-sectional shape is defined in a region where the photoresist is removed by etching the conductor layer, and a conductor wiring having a square cross-sectional shape is formed in a region where the photoresist is not removed. A second etching step.

  In order to solve the above problems, a fourth method of manufacturing a tape wiring substrate of the present invention includes a step of forming a first photoresist on a base material having a conductor layer on a flexible insulating base material, A step of forming an opening in the first photoresist, a first etching step of etching the conductor layer using the first photoresist in which the opening is formed as a mask, and a step of removing the first photoresist; Forming a second photoresist on the substrate; forming an opening in the second photoresist; and etching the conductor layer using the second photoresist in which the opening is formed as a mask. A second etching step of forming a conductor wiring and a step of removing the second photoresist. In the step of forming an opening in the second photoresist, the second photoresist The opening is formed in a portion where the width of the conductor wiring of the strike is relatively narrow, and in the second etching step, the thickness of the conductor wiring is formed thinner than the conductor wiring formed in the first etching step. .

  According to the present invention, by forming the wide portion and the narrow portion in the conductor wiring, there is no restriction on the mounting direction of the semiconductor chip and the external substrate with respect to the conductor wiring, and the semiconductor chip with a narrow pitch can be joined. The tape wiring board which enables is provided.

  In the tape wiring board of the present invention, the conductor wiring has an inner lead portion formed in a portion where a semiconductor chip can be mounted, and the inner lead portion has a triangular cross-sectional shape. You can also.

  Further, the conductor wiring may be configured such that the wiring width of the portion having a square cross-sectional shape is wider than the wiring width of the portion having a triangular cross-sectional shape.

  In addition, the conductor wiring can be configured such that the thickness of the portion having a square cross-sectional shape is thicker than the thickness of the portion having a triangular cross-sectional shape.

  The inner lead portion may have a protruding electrode having a triangular cross-sectional shape.

  In addition, an external connection terminal is formed at an end of the conductor wiring opposite to the inner lead portion, and the cross-sectional shape of the external connection terminal may be a quadrangle.

  Moreover, it can be set as the structure which has a support part connected to the front-end | tip of the inner lead part of the said conductor wiring, and a cross-sectional shape is a rectangle.

  Moreover, the cross-sectional shape of the part where the cross-sectional shape of the conductor wiring is a quadrangle can be configured to be a trapezoid having a wide side on the side connected to the insulating base.

  In addition, a boundary region between the trapezoidal section of the conductor wiring and the triangular section of the conductor wiring may be configured such that the sectional shape of the conductor wiring gradually becomes a triangle from the trapezoid. it can.

  Moreover, it can be set as the structure by which the hole is formed so that the inner lead part of the said conductor wiring may be exposed to the area | region in which the said semiconductor chip was formed so that mounting was possible.

  A semiconductor device of the present invention includes the above-described tape wiring substrate and a semiconductor chip formed on the tape wiring substrate.

  Further, in the fourth method for manufacturing a tape wiring substrate, the thin section of the conductor wiring may have a triangular cross-sectional shape.

(Embodiment 1)
FIG. 1 is a plan view showing the structure of the tape wiring board 1a according to the first embodiment of the present invention, as viewed from the side where the conductor wiring 4a of the tape wiring board 1a is provided. The flexible substrate 2a is formed of an insulating tape base material such as a polyimide material or a PET (polyester terephthalate) material. The thickness is preferably about 10 μm to about 100 μm, but other thicknesses may be used. The semiconductor chip mounting portion 3 is an area where a semiconductor chip (not shown) is mounted.

  A plurality of conductor wirings 4a are arranged on the flexible substrate 2a, and are conductors that connect the semiconductor chip and the outside and transmit signals. The conductor wiring 4a is preferably made of copper, but any conductive material such as aluminum may be used. The narrow portion 5a is a portion where the wiring width of the conductor wiring 4a is narrow. The narrow portion 5a includes an inner lead portion that requires a narrow pitch because it is connected to the electrode pad of the semiconductor chip in the semiconductor chip mounting portion 3 of the conductor wiring 4a. The wide portion 6a is a portion having a wider wiring width than the narrow portion 5a of the conductor wiring 4a, and includes an outer lead portion connected to the outside such as a glass panel or a mother substrate.

  FIG. 2 is a perspective view of a region A indicated by a one-dot chain line of the tape wiring board 1a shown in FIG. The narrow portion 5a of the conductor wiring 4a has a triangular cross section, and the wide portion 6a has a trapezoidal (quadrangle) cross section. The narrow portion 5a is formed with a narrower wiring width and a smaller thickness than the wide portion 6a. However, the boundary between the narrow portion 5a and the wide portion 6a is disposed at the bent portion of the conductor wiring 4a and is formed so that the wiring width is continuous. For this reason, the conductor wiring 4a can narrow a wiring pitch in an inner lead part. A flat portion 7 having a certain width or more is formed at the upper end of the wide portion 6a.

  The wide portion 6a, particularly the outer lead portion, is generally joined to a glass panel or mother substrate via an ACF (anisotropic conductive film) or the like. Since the flat portion 7 of the wide portion 6a is formed flat, it is possible to improve the bonding property with a glass panel or a mother substrate.

  Next, a method for manufacturing the tape wiring board 1a will be described. 3-6 is process drawing which shows the manufacturing method of the tape wiring board 1a. 3-6, (a) is a top view, (b) is sectional drawing which shows the structure of the AA 'cross section of (a).

  First, as shown in FIG. 3, a conductor layer 8 for conductor wiring having a thickness of about 5 μm to 40 μm is formed on the flexible substrate 2a by a pressure bonding method or a plating method. Note that the conductor layer 8 may have a thickness other than 5 μm to 40 μm. Next, a photoresist layer 9 for wiring formation is formed on the conductor layer 8. The photoresist layer 9 may be either a negative type or a positive type. The thickness of the photoresist layer 9 can be from about 10 μm to about 100 μm.

  Next, as shown in FIG. 4, the resist is exposed and developed and removed by a photolithography method so that the resist remains on a region where a desired pattern wiring is to be formed on the photoresist layer 9. At this time, the narrow resist 10a is formed by relatively narrowing the pattern width of the portion for forming the narrow portion 5a having a narrow wiring width. At the same time, the width of the wide resist 4 is made wider than that of the narrow resist 10a by forming the pattern width of a portion for forming flatness on the surface of the wiring to some extent, such as the outer lead portion. Form.

  Next, as shown in FIG. 5, using the patterned photoresist layer 9 as a mask, unnecessary portions of the conductor layer 8 are removed by wet etching to form the conductor wiring 4a. In the wet etching of the conductor layer 8, since the surface of the conductor layer 8 is isotropically etched, the width of the conductor wiring on the side in contact with the photoresist layer 9 in the conductor wiring 4a is narrowed. In the wet etching of the conductor layer 8, adjustment is made so that the cross section of the narrow portion 5a below the narrow resist 10a becomes a triangle and the cross section of the wide portion 6a below the wide resist 11a becomes a trapezoid.

  The cross-sectional shape of the conductor wiring 4a depends on the resist pattern and the thickness of the conductor layer. It also depends on the type and method of the etching chemical. For example, copper is used as the conductor layer 8 and a general copper sulfate solution is used as the etching solution. When the thickness of the conductor layer 8 is 25 μm, the width of the narrow resist 10a is 15 μm, the width of the wide resist 11a is 40 μm, and the wet etching is performed, the cross section of the narrow portion 5a becomes a triangle, and the cross section of the wide portion 6a The flat part 7 had a trapezoidal width of 15 μm. Further, the thickness of the narrow portion 5a is about 2 μm thinner than the thickness of the wide portion 6a.

  Next, as shown in FIG. 6, the narrow resist 10a and the wide resist 11a are removed to expose the conductor wiring 4a. Through the above steps, the tape wiring substrate 1a shown in FIG. 1 in which the cross-sectional shape of the narrow portion 5a is a triangle and the cross-sectional shape of the wide portion 6a is a trapezoid (square) can be manufactured.

  7A and 7B show the configuration of the semiconductor device 20 in which the semiconductor chip 21 is mounted on the semiconductor chip mounting portion of the tape wiring substrate 1a. FIG. 7A is a plan view, and FIG. It is. For ease of understanding of the drawing, the semiconductor chip 21 in FIG. 4A is indicated by a broken line, and illustrations other than the protruding electrodes 23 are omitted.

  As shown in FIG. 7B, a protruding electrode 23 is formed on the electrode pad 22 formed on one main surface of the semiconductor chip 21. The electrode pad 22 is generally made of a material mainly composed of aluminum, but a conductor such as copper can also be used. The protruding electrode 23 may be formed on the semiconductor chip 21 or may be formed on the narrow portion 5a of the conductor wiring 4a. It is also possible to adopt a structure without the protruding electrode 23. The protruding electrode 23 is preferably formed of a single layer body, a multilayer body or an alloy body made of a material mainly composed of nickel, copper, aluminum, gold, silver, palladium, tin or the like. As a method for forming the protruding electrode 23 formed on the electrode pad 22, an electroless plating method or an electrolytic plating method can be used, but it can also be formed by a vapor deposition method or a sputtering method.

  As a method of connecting the semiconductor chip 21 to the tape wiring substrate 1a, a pressure heating method, an ultrasonic bonding method, or the like can be used. The surface of the narrow portion 5a is preferably tin-plated. When the protruding electrode 23 is made of gold, the connection between the narrow portion 5a and the protruding electrode 23 is a tin-gold eutectic bond.

  The passivation 24 is a protective film that protects the semiconductor chip 21. A sealing resin 25 is filled between the semiconductor chip 21 and the tape wiring substrate 1a. As a result, the connection between the tape wiring substrate 1a and the semiconductor chip 21 can be stabilized.

  FIG. 8 is a cross-sectional view showing a configuration in which the semiconductor device 20 formed as described above is mounted on an external substrate 33 such as a glass panel or a mother substrate. The solder resist layer 31 is formed on the conductor wiring 4a in order to protect the conductor wiring 4a. The external substrate 33 is a glass panel. In the outer lead part, the flat part 7 of the wide part 6 a is connected to the glass panel 33 by an ACF (anisotropic conductive film) 32.

  With the above configuration, the semiconductor device 20 can join the semiconductor chip 21 having the electrode pads 22 with a narrow pitch to the tape wiring substrate 1a without short-circuiting the adjacent protruding electrodes 23. Furthermore, the semiconductor device 20 having the narrow-pitch semiconductor chip 21 can be stably mounted on an external substrate such as a glass panel.

  FIG. 9 is a perspective view showing another configuration of the tape wiring board 1a. In the tape wiring substrate 1b, a boundary between the narrow portion 5b and the wide portion 6b is formed in the straight portion of the conductor wiring 4b. Accordingly, the width of the conductor wiring 4b is discontinuous at the boundary between the narrow portion 5b and the wide portion 6b. What is necessary is just to arrange | position the boundary of the narrow resist 10a and the wide resist 11a shown in FIG. 4 in the linear part of conductor wiring.

  FIG. 10 is a perspective view showing another configuration of the tape wiring board 1a. In the tape wiring substrate 1c, the intermediate portion 12 is formed between the wide portion 6c and the narrow portion 5c of the conductor wiring 4c, and the width of the wide portion 6c is gradually reduced to become the narrow portion 5c. Yes. The intermediate portion 12 may be formed by wet etching using a resist in which the width of the narrow resist is gradually narrowed from the width of the wide resist between the wide resist and the narrow resist as a mask.

  FIG. 11 is a plan view showing a configuration of a tape wiring substrate 1d having a configuration different from that of the tape wiring substrate 1a. The tape wiring substrate 1d has a flexible substrate 2d in which an opening 34 is provided in the semiconductor chip mounting portion 3 for use as a TCP. Even if comprised in this way, the same effect can be acquired.

(Embodiment 2)
FIG. 12 is a plan view showing the structure of the tape wiring board 1e in the second embodiment of the present invention. The tape wiring board 1e according to the present embodiment is the same as the tape wiring board 1a according to the first embodiment except that the support part 41 having the same width as the wide part 6a is formed at the tip of the narrow part 5a. This is the same as the tape wiring board 1a. In the tape wiring board 1e, the same components as those of the tape wiring board 1a are denoted by the same reference numerals and description thereof is omitted.

  FIG. 13 is a perspective view showing a region B indicated by a one-dot chain line of the tape wiring board 1e shown in FIG. The support portion 41 has a rectangular cross section similar to the wide portion 6a, and is connected to the narrow portion 5a. When the semiconductor chip is mounted, the support portion 41 does not contact the semiconductor chip or contacts the insulating passivation and does not perform an electrical operation.

  The manufacturing method of tape wiring substrate 1e is the same as the manufacturing method of tape wiring substrate 1a in the first embodiment. However, in FIG. 5B in the manufacturing process of the tape wiring substrate 1a according to the first embodiment, in the semiconductor chip mounting portion 3, the narrow resist 10a floats from the narrow portion 5a. Therefore, the shape of the narrow portion 5a by wet etching is not stable. The tape wiring substrate 1e in the present embodiment supports the narrow resist 10a in the semiconductor chip mounting portion 3 by the support portion 41, can prevent the narrow resist 10a from floating, and can stabilize the shape of the narrow portion 5a. it can.

(Embodiment 3)
FIG. 14 is a perspective view showing a configuration of a tape wiring board 1f according to Embodiment 3 of the present invention. The tape wiring substrate 1f according to the present embodiment is the same as the tape wiring substrate 1a except that the protruding electrode 42 is formed on the narrow portion 5a in the tape wiring substrate 1a according to the first embodiment. In the tape wiring substrate 1f, the same components as those of the tape wiring substrate 1a are denoted by the same reference numerals and description thereof is omitted.

  A protruding electrode 42 having a triangular cross section is formed in the narrow portion 5a. The protruding electrode 42 is formed by performing electroless plating or electrolytic plating on the narrow portion 5a. Since the cross-sectional shape of the narrow portion 5a is a triangle, when electroless plating or electrolytic plating is performed, the plated portion grows relatively imitating the shape of the narrow portion 5a, so that the protruding electrode 42 has a triangular shape. Formed as.

  With this structure, when the semiconductor chip and the electrode pad are pressure-weighted when bonded to the electrode pad of the semiconductor chip, the protruding electrode is deformed and the connection between the protruding electrode and the electrode pad is stabilized.

(Embodiment 4)
As a fourth embodiment of the present invention, a method for manufacturing a tape wiring substrate 1a different from the method for manufacturing the tape wiring substrate 1a shown in the first embodiment will be described. 15 to 19 are process diagrams showing a method for manufacturing the tape wiring board 1a according to the first embodiment. 15-19, (a) is a top view, (b) is sectional drawing which shows the structure of CC 'cross section of (a).

  First, as shown in FIG. 15, a conductor layer 8 for conductor wiring having a thickness of about 5 μm to 40 μm is formed on the flexible substrate 2a by a pressure bonding method, a plating method, or the like. Note that the conductor layer 8 may have a thickness other than 5 μm to 40 μm. Next, a photoresist layer 9 for wiring formation is formed on the conductor layer 8. The photoresist layer 9 may be either a negative type or a positive type. The thickness of the photoresist layer 9 can be from about 10 μm to about 100 μm.

  Next, as shown in FIG. 16, the resist is exposed and developed and removed by a photolithography method so that the resist remains on a region where a desired pattern wiring is to be formed on the photoresist layer 9. At that time, a narrow resist 10g is formed by relatively narrowing the pattern width of the portion for forming the narrow portion 5a having a narrow wiring width. Further, the wide resist 11g is formed by making the pattern width of the wide portion 6a, particularly the portion for forming flatness on the surface of the wiring to some extent, such as the outer lead portion, wider than the width of the narrow resist 10g. Form.

  Next, as shown in FIG. 17, using the photoresist layer 9 on which the pattern is formed as a mask, unnecessary portions of the conductor layer 8 are removed by wet etching. In the wet etching of the conductor layer 8, since the surface of the conductor layer 8 is isotropically etched, the width of the conductor layer 8 on the side in contact with the photoresist layer 9 is narrowed. In the wet etching of the conductor layer 8, the cross section of the narrow conductor portion 51a under the narrow resist 10g is trapezoidal, and the cross section of the wide conductor portion 52a under the wide resist 11g is Adjust so that the trapezoid is wider than the cross section.

  The cross-sectional shape of the conductor wiring 4a depends on the resist pattern and the thickness of the conductor layer. It also depends on the type and method of the etching chemical. For example, copper is used as the conductor layer 8 and a general copper sulfate solution is used as the etching solution. For example, wet etching is performed with the thickness of the conductor layer 8 being 25 μm, the width of the narrow resist 10 g being 15 μm, and the width of the wide resist 11 g being 40 μm. At this point, the etching is not completely performed, and there may be a portion where the conductor wiring is partially connected on the contact surface with the tape base material.

  Next, as shown in FIG. 18, the patterned photoresist layer 9 is removed to expose the conductor layer 8.

  Next, as shown in FIG. 19, second wet etching is performed on the narrow conductor portion 51a and the wide conductor portion 52a until the cross-sectional shape of the narrow conductor portion 51a becomes a triangle. By performing the second wet etching on the narrow conductor portion 51a and the wide conductor portion 52a, the narrow portion 5a and the wide portion 6a are formed, respectively. At this time, the shape of the wide portion 6a was a trapezoid in which the width of the flat portion 7 of the wiring was 15 μm. Further, the thickness of the conductor wiring 4a is about 1 μm thinner in the narrow portion 5a than in the wide portion 6a. Also in the manufacturing method as described above, the tape wiring substrate 1a can be manufactured.

  As another manufacturing method of the tape wiring substrate 1a, after the step shown in FIG. 17, photolithography is performed using a photomask having an entire area where the narrow portion 5a is to be formed to remove the narrow resist 10g. . Here, since the pattern once exposed and developed is exposed and developed again, the material of the photoresist layer 9 shown in FIG. Thereafter, a second wet etching is performed. By the second wet etching, the narrow conductor portion 51a is etched not only in the side surface direction but also in the thickness direction to form the narrow portion 5a, and the wide conductor portion 52a is completely etched to form a desired trapezoid (rectangle). Wide portion 6a is formed. Thereafter, the wide resist 11g is removed to expose the conductor wiring 4a.

  With the above manufacturing method, the tape wiring substrate 1a in which the cross-sectional shape of the narrow portion 5a is a triangle and the cross-sectional shape of the wide portion 6a is a trapezoid (rectangle) can be formed.

(Embodiment 5)
As a fifth embodiment of the present invention, a method for manufacturing a tape wiring substrate 1b different from the method for manufacturing the tape wiring substrate 1b shown in the first embodiment will be described. 20 to 25 are process diagrams showing a method for manufacturing the tape wiring substrate 1b according to the embodiment of the present invention. 20 to 25, (a) is a plan view, and (b) is a cross-sectional view showing the configuration of the DD ′ cross section of (a).

  First, as shown in FIG. 20, a conductor layer 8 for conductor wiring having a thickness of about 5 μm to 40 μm is formed on a flexible substrate 2a by a pressure bonding method, a plating method, or the like. The conductor layer 8 may be formed to a thickness other than 5 μm to 40 μm. Next, a photoresist layer 9 is formed on the conductor layer 8. The photoresist layer 9 may be either a negative type or a positive type. The thickness of the photoresist layer 9 can be from about 10 μm to about 100 μm.

  Next, as shown in FIG. 21, the photoresist layer 9 is exposed and developed and removed by photolithography so that the wiring forming resist 61 remains on the region where a desired pattern wiring is to be formed. To do. At that time, the narrow resist 10h is formed by making the pattern width of the portion for forming the narrow portion 5b having a narrow wiring width wider than the width of the narrow portion 5b. Further, the wide resist 11h is formed by making the pattern width of the wide portion 4b, in particular, the portion for forming flatness required to some extent on the surface of the wiring, such as the outer lead portion, wider than the width of the narrow resist 10h. Form. In FIG. 21, the length between the narrow resists 10h is shorter than the length between the wide resists 11h.

  Next, as shown in FIG. 22, unnecessary portions of the conductor layer 8 are removed by wet etching using the patterned photoresist layer 9 as a mask. In the wet etching of the conductor layer 8, since the surface of the conductor layer 8 is isotropically etched, the width of the conductor wiring on the side in contact with the photoresist layer 9 is narrowed.

  The cross-sectional shape of the conductor wiring 4b depends on the resist pattern and the thickness of the conductor layer. It also depends on the type and method of the etching chemical. For example, copper is used as the conductor layer 8 and a general copper sulfate solution is used as the etching solution. Wet etching is performed with the thickness of the conductor layer 8 being 25 μm, the width of the narrow resist 10 h being 15 μm, and the width of the wide resist 11 h being 40 μm.

  Therefore, wet etching is performed so that the conductor layer 8 under the wide resist 11h becomes the wide portion 6b. At this time, the conductor layer 8 (narrow conductor layer 51d) under the narrow resist 10h may have a trapezoidal cross-sectional shape or may be integrated with the adjacent narrow conductor layer 51d. Next, the narrow resist 10h and the wide resist 11h are removed, and the wide portion 6b and the narrow conductor layer 51d are exposed. Next, as shown in FIG. 23, a resist layer is formed, the resist layer in a region other than covering the wide portion 6b is removed, and a second resist 61 exposing the narrow conductor layer 51d is formed.

  Next, as shown in FIG. 24, using the second resist 61 as a mask, the narrow conductor layer 51d is wet etched to form a narrow portion 5b having a triangular cross-sectional structure. Thereafter, as shown in FIG. 25, the second resist 61 is removed.

  Through the above steps, the tape wiring substrate 1b in which the cross-sectional shape of the wide portion 6b is trapezoidal while the cross-sectional shape of the narrow portion 5b is triangular can be formed. As a result, the narrow part 5b became a triangle after etching, and the flat part 7 of the wide part 6b became a trapezoid whose width was 15 μm. Also, the thickness of the conductor wiring 4b is about 2 μm thinner at the narrow portion 5b than at the wide portion 6b.

  As in the above embodiment, in the tape wiring substrate 1b, the semiconductor device, and the mounting structure, the electrode pad connection portions of the semiconductor chip have a narrow wiring width and a narrow wiring width, and a certain amount of wiring is formed on the wiring surface such as the outer lead portion. In a region where flatness is required, a flat region can be secured stably. Thereby, it is possible to provide a semiconductor device having a high manufacturing yield while using a narrow-pitch semiconductor chip.

  In addition, by making the length between the narrow resists 10h shorter than the length between the wide resists 11h, the length between the narrow portions 5b of the conductor wiring 4b and the length between the wide portions 6b become approximately the same. For this reason, it is possible to prevent a short circuit between the conductor wirings 4b and to perform wiring in a small space.

  INDUSTRIAL APPLICABILITY The present invention can be used for a tape wiring substrate that enables mounting of a semiconductor chip with a narrow pitch while realizing stable outer lead mounting.

The top view which shows the structure of the tape wiring board which concerns on Embodiment 1 of this invention The fragmentary perspective view which shows the structure of a tape wiring board same as the above (A) which shows the manufacturing method of a tape wiring board same as the above is a top view, (b) is AA 'sectional drawing 3A is a plan view, and FIG. 3B is a cross-sectional view taken along line AA ′. 4A is a plan view and FIG. 4B is a cross-sectional view taken along line AA ′. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along line AA ′. 1A is a plan view showing the configuration of a semiconductor device according to Embodiment 1 of the present invention, and FIG. Sectional drawing which shows the structure which mounted the semiconductor device same as the above on the external substrate The perspective view which shows the structure of the tape wiring board different from the tape wiring board which concerns on Embodiment 1 of this invention. The perspective view which shows the structure of the tape wiring board different from the tape wiring board which concerns on Embodiment 1 of this invention. The top view which shows the structure of the tape wiring board different from the tape wiring board which concerns on Embodiment 1 of this invention The top view which shows the structure of the tape wiring board based on Embodiment 2 of this invention The fragmentary perspective view which shows the structure of a tape wiring board same as the above The partial perspective view which shows the structure of the tape wiring board based on Embodiment 3 of this invention. (A) which shows the manufacturing method of the tape wiring board which concerns on Embodiment 4 of this invention is a top view, (b) is CC 'sectional drawing. FIG. 15A is a plan view showing the next step of FIG. 15, and FIG. FIG. 16A is a plan view showing the next step, and FIG. 16B is a cross-sectional view along CC ′. FIG. 17A shows a step subsequent to FIG. 17, and FIG. 17B is a cross-sectional view taken along the line CC ′. FIG. 18A shows a step subsequent to FIG. 18, and FIG. 18B is a cross-sectional view taken along the line CC ′. (A) which shows the manufacturing method of the tape wiring board which concerns on Embodiment 4 of this invention is a top view, (b) is DD 'sectional drawing. 20A is a plan view and FIG. 20B is a DD ′ sectional view showing the next step of FIG. FIG. 21A is a plan view showing the next step of FIG. 21, and FIG. FIG. 22A is a plan view showing the next step of FIG. 22, and FIG. FIG. 23A is a plan view showing the next step of FIG. 23, and FIG. FIG. 24A shows a step subsequent to FIG. 24, and FIG. 24B is a cross-sectional view along DD ′. Partial sectional view showing the structure of a conventional semiconductor device

Explanation of symbols

1a, 1b, 1c, 1d, 1e, 1f Tape wiring board 2a, 2d Flexible board 3 Semiconductor chip mounting part 4a, 4b, 4c Conductor wiring 5a, 5b, 5c Narrow part 6a, 6b, 6c Wide part 7 Flat Part 8 Conductor layer 9 Photoresist layer 10a, 10g, 10h Narrow resist 11a, 11g, 11h Wide resist 20 Semiconductor device 21 Semiconductor chip 22 Electrode pad 23 Projection electrode 24 Passivation 25 Sealing resin 31 Solder resist layer 32 Anisotropic conductivity Film 33 External substrate 34 Opening portion 41 Support portion 42 Protruding electrodes 51a and 51d Narrow conductor portions 52a and 52d Wide conductor portion 61 Second resist

Claims (16)

A flexible insulating substrate;
In a tape wiring board provided with a conductor wiring formed on the insulating base material,
A tape wiring board, wherein the conductor wiring has a triangular section and a quadrangular section. The conductor wiring has an inner lead portion formed in a portion where the semiconductor chip can be mounted,
The tape wiring board according to claim 1, wherein the inner lead portion has a triangular cross-sectional shape.   3. The tape wiring board according to claim 1, wherein the conductor wiring has a wider wiring width in a portion having a square cross-sectional shape than a wiring width in a portion having a triangular cross-sectional shape.   The tape wiring substrate according to any one of claims 1 to 3, wherein the conductor wiring has a thicker portion having a square cross-sectional shape than a portion having a triangular cross-sectional shape.   The tape wiring substrate according to any one of claims 2 to 4, wherein a protruding electrode having a triangular cross-sectional shape is formed on the inner lead portion.   The tape wiring according to any one of claims 2 to 5, wherein an external connection terminal is formed at an end portion of the conductor wiring opposite to the inner lead portion, and a cross-sectional shape of the external connection terminal is a quadrangle. substrate.   The tape wiring substrate according to any one of claims 2 to 6, further comprising a support portion connected to a tip of an inner lead portion of the conductor wiring and having a quadrangular cross-sectional shape.   The tape wiring substrate according to any one of claims 1 to 7, wherein a cross-sectional shape of a portion where the cross-sectional shape of the conductor wiring is a quadrangle is a wide trapezoid on a side connected to the insulating base.   9. The tape wiring according to claim 8, wherein the cross-sectional shape of the conductor wiring has a triangular shape in which the cross-sectional shape of the conductor wiring gradually becomes narrower from the trapezoid in a boundary region between the trapezoidal section and the triangular section. substrate.   The tape wiring board according to claim 2, wherein a hole is formed so that an inner lead portion of the conductor wiring is exposed in a region where the semiconductor chip can be mounted. The tape wiring board according to claim 1,
A semiconductor device having a semiconductor chip formed on the tape wiring substrate. Forming a photoresist on a substrate having a conductor layer on a flexible insulating substrate;
Forming an opening in the photoresist;
Etching the conductor layer using the photoresist in which the opening is formed as a mask to form a conductor wiring; and
And removing the photoresist.
In the step of forming the opening, the opening is formed so that the mask width of the portion where the width of the conductor wiring is relatively narrow is narrowed with respect to the portion where the width of the conductor wiring is relatively wide,
In the etching step, the tape wiring is etched so that the cross-sectional shape of the relatively wide portion of the conductor wiring is a square and the cross-sectional shape of the relatively narrow portion of the conductor wiring is a triangle. A method for manufacturing a substrate. Forming a photoresist on a substrate having a conductor layer on a flexible insulating substrate;
Forming an opening in the photoresist;
A first etching step of etching the conductor layer using the photoresist in which the opening is formed as a mask;
Removing the photoresist;
A second etching step of etching the conductor layer to form a conductor wiring;
In the step of forming the opening, the opening is formed in the photoresist so that a mask width of a portion where the width of the conductor wiring is relatively narrow is narrowed with respect to a portion where the width of the conductor wiring is relatively wide. Forming part,
In the second etching step, the tape is etched so that the cross-sectional shape of the portion where the width of the conductor wiring is relatively wide is a square and the cross-sectional shape of the portion where the width of the conductor wiring is relatively narrow is a triangle. A method for manufacturing a wiring board. Forming a photoresist on a substrate having a conductor layer on a flexible insulating substrate;
Forming an opening in the photoresist;
Etching the conductor layer using the photoresist in which the opening is formed as a mask;
Removing a portion of the photoresist;
Using the partially removed photoresist as a mask, the conductor layer is etched to define a conductor wiring having a triangular cross section in the region where the photoresist is removed, and in the region where the photoresist is not removed A method for manufacturing a tape wiring board, comprising: a second etching step in which a rectangular conductor wiring is formed. Forming a first photoresist on a substrate having a conductor layer on a flexible insulating substrate;
Forming an opening in the first photoresist;
A first etching step of etching the conductor layer using the first photoresist in which the opening is formed as a mask;
Removing the first photoresist;
Forming a second photoresist on the substrate;
Forming an opening in the second photoresist;
Etching the conductor layer using the second photoresist in which the opening is formed as a mask to form a conductor wiring; and
Removing the second photoresist,
In the step of forming an opening in the second photoresist, the opening is formed in a portion where the width of the conductor wiring of the second photoresist is relatively narrow,
In the second etching step, a method of manufacturing a tape wiring substrate, wherein a thickness of the conductor wiring is formed thinner than the conductor wiring formed in the first etching step.   The method for manufacturing a tape wiring substrate according to claim 15, wherein the thin portion of the conductor wiring has a triangular cross-sectional shape.

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