JPH04105336A - Connection structure of tab type semiconductor device and the like - Google Patents

Abstract

PURPOSE:To obtain a connection structure of a pattern and a lead which is free from position deviation, by forming recessed parts which have the same pitch as the leads of a TAB system semiconductor device and the like and a width larger than the lead, at the position of a substrate where a pattern is formed, and forming the pattern in the bottom parts of the recessed parts. CONSTITUTION:In connection structure wherein leads 14 of the flexible tape or a TAB type semiconductor device 11 are connected with a pattern 2 formed on a substrate 1, recessed parts 3 which have the same pitch as the leads 14 and a width (b) larger than the width (c) of the lead 14 are formed at positions of the substrate 1 where a pattern 2 is formed, and said pattern 2 is formed in the bottom parts of the recessed parts 3. For example, at positions of a glass substrate 1 where an electrode pattern 2 is formed, the recessed parts 3 wherein the depth (a) is 5-35mum and the width (b) is a little larger than the width (c) of the lead 14 are formed at the same pitch as the leads 14, and the electrode pattern 2 is formed in the bottom parts. The electrode pattern 2 and the leads 14 are position-aligned, and an anisotropic bonding film 4 is interposed between them. The leads 14 are connected with the electrode pattern 12 by applying heat and pressure to the film 12.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a TAB type semiconductor device in which a semiconductor element is mounted on a flexible film such as a polyimide film and connected to an inner lead provided on the film. Alternatively, the present invention relates to a connection structure for a TAB type semiconductor device, etc., in which a flexible tape formed by providing a lead on the above-mentioned film is connected to a pattern provided on a substrate.

[Prior Art] A so-called TAB type semiconductor device, in which a semiconductor element is mounted on a flexible film such as a polyimide film and connected to leads provided on the film, is widely used in practice. In addition, flexible tapes have also been put into practical use, in which a large number of leads are provided on the above-mentioned film, and the flexibility of the tapes is utilized to connect substrates.

FIG. 3 is a schematic diagram showing an example of a conventional connection structure of this type, and FIG. 4 is an enlarged view of the main part thereof. In the figure, (1) is a glass substrate constituting, for example, a liquid crystal panel, and a large number of electrode patterns (2) are provided on its outer edge. (11
) is a TAB type semiconductor device with a flexible film (12)
A semiconductor element (13) is mounted in the center of the film, and its electrodes are respectively connected to leads (14) formed on the film (12).

Note that (5) is, for example, a printed circuit board, (15) is formed with a large number of leads (IB), and electrically connects the electrode pattern provided on the glass substrate (1) and the electrode pattern provided on the printed circuit board (5). It is a flexible tape that connects the

To connect the leads (14) of the semiconductor device (11) to the electrode pattern (2) of the glass substrate (1) as described above,
As shown in Figure 5, the electrode pattern (
2), the leads (I4) of the semiconductor device (11) are aligned (positioned), an anisotropic adhesive film (4) is interposed between the two, and the film (12) is heated and pressurized to form an electrode pattern. Connect the lead (14) to (2).

The flexible tape (15) is connected to the glass substrate (1) and the printed circuit board (5) in the same manner as described above.

[Problem to be solved by the invention] Glass substrate (1) or printed circuit board (5) as described above and TAB type semiconductor device (11) or flexible tape (
15), anisotropic adhesive film (
When connecting the two in step 4), the film (12) stretches due to heat and pressure, so the electrode pattern (2) and lead (
14), and as shown in Figures 5 and 6, a positional deviation (α) occurs between the two, and some of the electrode patterns (2) and leads (14) If sufficient connection area is not available, the lead may sometimes fail (14)
may come off from the electrode pattern 2), making it impossible to connect.

Furthermore, even after connection, the anisotropic adhesive film (4) may loosen due to heat, impairing reliability.

As shown in FIG. 7, this tendency for positional deviation became more pronounced as the connection pitch became smaller.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to obtain a connection structure between a pattern and a lead without the risk of positional deviation.

[Means for Solving the Problems] The connection structure of a TAB type semiconductor device according to the present invention has a connection structure in which a pattern on a substrate is formed with the same pitch as the leads of a TAB type semiconductor device, etc., but wider than the width of the bracket leads. A concave portion with a certain width is provided, and a pattern is formed on the bottom of the concave portion.

[Operation] Align a portion of the adhesive such as a TAB type semiconductor device with the pattern of the substrate, fit the leads into the recesses of the substrate, and connect the pattern and the leads with a bonding material.

[Example] FIG. 1 is a sectional view schematically showing an example of the present invention, and FIG. 2 is a partially enlarged view thereof. Note that the same parts as in the prior art explained in FIG. 5 are given the same reference numerals, and the explanation will be omitted. (
3) is a recess formed by etching or the like at the same pitch as the leads (14) at the position where the electrode pattern (2) is to be formed on the glass substrate (1), and in the example, the depth (a) is 5.
~35-1 width (b) is 1.5-1 of the width (e) of the lead (14).
It was increased by 2 to 1.5 times. At the bottom of this recess (3), vapor deposition,
An electrode pattern (2) is formed by sputtering or the like.

In order to connect the TAB type semiconductor device (II) to the glass substrate (1) having the electrode pattern (2) provided in the recess (3) as described above, first, the electrode pattern (2) of the glass substrate (1) is connected.
2) and the leads (14) of the TAB type semiconductor device (11), then align the concave part (1) of the glass substrate (1).
3) For example, an anisotropic adhesive film (4) is inserted inside.

Next, the TAB semiconductor device (11) is lowered and its leads (14) are fitted into the four parts (3), and the film (12) is heated and pressurized to attach the leads (14) to the electrode pattern (2). Connecting.

In this case, the width (b) of the fourth part (3) is approximately 1.2 to 1.5 times the width (C) of the lead (14), so
Even if the alignment between the electrode pattern (2) and the lead (14) is somewhat rough, the two can be reliably connected, making alignment extremely easy. Furthermore, even if the film (12) is slightly stretched due to heating and pressure during connection, the recess (3) and therefore the width (b) of the electrode pattern (2) will be
) is formed to be larger than the width (c) of the lead (14) to provide a margin, so that it can be sufficiently covered and no connection failure will occur.

Furthermore, most of the lead (14) in the thickness direction has a recess (3).
), the glass substrate (1) and the film (
12), and therefore the volume of the anisotropic adhesive film (4) filled in this space is also small. Therefore, even if the anisotropic adhesive film (4) loosens due to heat, reliability will not be impaired.

TAB type semiconductor device (11) or flexible tape (
15) and the electrode pattern (2) provided on the glass substrate (1), the width and spacing (
Table 1 shows an example of the relationship with the gap).

Table 1 For each pitch shown in Table 1 above, TAB is applied to the electrode pattern (2) of the glass substrate (1) using the conventional technology and the present invention.
The leads (4) of the semiconductor device (11) were connected using the anisotropic connection film (4), and the results of investigating the positional deviation (α) are shown in FIG. As is clear from the figure,
In the conventional technology, as the connection pitch becomes smaller (fine pattern), the positional deviation (α) becomes larger, and the connection pitch becomes 10.
In the case of 0Ia+, the width could reach 351a1 (70% of the width 50- of the electrode pattern (2)), and the yield was low.

In contrast, in the present invention, the positional deviation was zero regardless of the size of the connection pitch, and a connection structure with high yield and reliability was obtained.

In the above explanation, a recess (3) is formed in the glass substrate (1), and the electrode pattern (2) provided in the recess (3) is
TAB type semiconductor device (11) or flexible tape (
Although the case has been described in which the leads (14) provided in I5) are connected, the present invention can also be implemented on substrates other than glass substrates.

Furthermore, in the above embodiment, the electrode pattern (2) and the lead (
14) using an anisotropic adhesive film (4), various bonding materials such as solder and conductive adhesive can be used in the present invention.

[Effects of the Invention] As is clear from the above description, the present invention provides four parts having a width wider than the lead width of a TAB type semiconductor device, etc. at the position of the pattern on the substrate, and forms a pattern at the bottom of each of the four parts. T
Since the leads of the AB type semiconductor device and the like are connected, the following effects can be obtained.

(1) Even if the alignment between the pattern and the lead is somewhat rough, it is possible to reliably connect the two.

(2) Since the leads are connected to the pattern by fitting into the recesses of the substrate wider than the width of the leads, the two can be reliably connected even if the film is slightly stretched due to heating, pressure, etc.

(3) Since the leads are accommodated in the recesses of the substrate, the space formed between the substrate and the film is small, and therefore the volume of the bonding material filled in this space is also small. Therefore, even if the bonding material loosens due to heat, reliability will not be compromised.

(4) For these reasons, it is possible to obtain a connection structure that is easy to work with, has high yield and reliability, and can be formed into fine patterns.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing an embodiment of the present invention, FIG. 2 is a partially enlarged view thereof, FIG. 3 is a schematic diagram showing an example of connection between a glass substrate, etc. and a TAB type semiconductor device, etc., and FIG. The figure is a partially enlarged view, FIG. 5 is a sectional view schematically showing an example of connection between a conventional glass substrate and a TAB type semiconductor device, and FIG. 6 is an explanation showing a state of misalignment between an electrode pattern and a lead. 7 are diagrams showing the relationship between connection pitch and positional deviation. (1) Niglass substrate, (2): Electrode pattern, (3):
recess, (5) niblint substrate, (11): TAB type semiconductor device, (12): film, (14): lead,
(15): Flexible tape. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] In a connection structure in which leads of a TAB type semiconductor device, flexible tape, etc. are connected to a pattern provided on a substrate, the pattern is formed on the substrate at the same pitch as the leads and wider than the width of the leads. A TA characterized in that a wide recess is provided and a pattern is formed on the bottom of the recess.
Connection structure for type B semiconductor devices, etc.