JP3298460B2 - BGA type semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a BGA (Ball Grid Array) type semiconductor device using a TAB tape, and more particularly, to a BGA type semiconductor device having high flatness while suppressing an increase in cost.

[0002]

2. Description of the Related Art In recent years, in semiconductor devices, as the number of inputs and outputs of semiconductor elements such as ICs and LSIs has increased, the input / output terminals have been arranged on a flat surface, so that the miniaturized structure has been relaxed.
The demand for GA structures (including CSPs) is increasing. On the other hand, demands for lowering the price of electronic-related parts have increased,
The search for a structure that meets this demand is also progressing for GA type semiconductor devices.

Under such circumstances, a semiconductor device having a Tape-BGA structure using a TAB tape capable of high-density wiring has attracted attention as a device capable of realizing a multi-pin, small package at low cost.

[0004] In a Tape-BGA type semiconductor device, it is important to ensure the flatness of the TAB tape in order to facilitate bonding of a ball terminal disposed on the back surface to a substrate or the like. For this reason, a TAB tape is generally attached to a metal plate called a stiffener. It is advantageous in terms of cost to perform the attachment to the stiffener through an adhesive that has been attached to one surface of the stiffener in advance.

FIG. 6 shows a conventional BGA type semiconductor device of this kind, in which a TAB tape 1 comprising a polyimide film 1A and a wiring pattern 1B formed on one surface thereof, and a TB tape 1
On the surface of the AB tape 1 on the side opposite to the wiring pattern 1B, an adhesive 2 previously laminated on one surface of each of the two is applied.
The stiffener 3 which is laminated and adhered is fixed to the back surface of the second stiffener 3 which is laminated on the TAB tape 1 via the adhesive 2 and the inner lead of the wiring pattern 1 is bumped to an electrode (not shown). 4A, the semiconductor element 4 and the wiring pattern 1B
And a ball terminal 6 attached to a predetermined position on the wiring pattern 1B and joined to a printed circuit board or the like.

However, according to this BGA type semiconductor device, since two stiffeners are stacked, the material is doubled.
In addition, since each lamination takes time, the cost is increased, and it is not possible to meet the demand for cost reduction.

On the other hand, as a conventional BGA type semiconductor device which solves such a problem, there is one shown in FIG. 7, and a TAB tape 1 comprising a polyimide film 1A and a wiring pattern 1B formed on one surface thereof, TAB
A stiffener 3 which is adhered to the surface of the tape 1 on the side opposite to the wiring pattern 1B via a pre-laminated adhesive 2 and has a rectangular recessed molded portion 3A having a predetermined height formed at a substantially central portion; A semiconductor element 4 fixed to a molded portion 3A of the stiffener 3 via an adhesive 2 and an inner lead of a wiring pattern 1B connected to an electrode (not shown) via the bump 4A;
It comprises a sealing resin 5 for sealing the B inner leads, and a ball terminal 6 attached to a predetermined position of the wiring pattern 1B and joined to a wiring pattern such as a printed circuit board.

FIG. 8 shows the stiffener 3 of the BGA type semiconductor device. A rectangular concave shaped portion 3A having a predetermined height is formed at a substantially central portion where the semiconductor element 4 is arranged by drawing by bending press working. .

[0009]

However, the conventional BGA
According to the die semiconductor device, since the molded portion is formed on the stiffener by bending press working, in order to reduce the cost, in the stiffener in which an adhesive is pasted on one surface in advance, the stiffener material at the corner of the bent portion is used. It is difficult to control the flow, and the residual stress of the stiffener material at this portion is large, resulting in a problem that the flatness of the product is reduced.

Accordingly, it is an object of the present invention to provide a BGA type semiconductor device which can increase the flatness while reducing the cost.

[0011]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention arranges a semiconductor element in a concave forming portion of a stiffener to increase the flatness while reducing the cost, and flattens the semiconductor element and the stiffener. In the BGA type semiconductor device configured by connecting the wiring patterns arranged in the portion, the formed portion of the stiffener is rectangular,
Tifna is formed when molding the molding part
Having openings at the four corners of the rectangle to absorb distortion.
A feature of the present invention is to provide a BGA type semiconductor device .

[0012]

[0013] The forming portion of the stiffener is rectangular, and the opening of the stiffener is formed over a predetermined length in first and second directions orthogonal to the rectangle from four corners of the rectangle. It is preferable that the configuration is such that:

It is preferable that the stiffener has a configuration in which an adhesive layer is previously attached to a surface on which the semiconductor element and the wiring pattern are arranged.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a BGA type semiconductor device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a first embodiment of the present invention.
1 shows a GA type semiconductor device. This BGA type semiconductor device
A TAB tape 1 comprising a polyimide film 1A and a wiring pattern 1B formed on one surface thereof, and a TAB tape 1 attached to a surface opposite to the wiring pattern 1B of the TAB tape 1 via an adhesive 2 laminated in advance, and A stiffener 3 having a rectangular recessed molded portion 3A of a predetermined height formed in the center portion, and the stiffener 3 is fixed to the molded portion 3A via an adhesive 2, and an inner lead of the wiring pattern 1B is attached to an electrode (not shown). The semiconductor element 4 connected via the bump 4A, the periphery of the semiconductor element 4 and the wiring pattern 1B
A sealing resin 5 for sealing the inner leads, a ball terminal 6 attached to a predetermined position of the wiring pattern 1B and joined to a wiring pattern such as a printed board, and a molded portion 3A.
Are formed at the four corners.

FIG. 2 shows the stiffener 3 of the BGA type semiconductor device. As described above, the substantially central portion is formed into a rectangular concave forming portion 3 having a predetermined height by drawing by bending press working.
A is formed, and openings 7 are formed in the four corners of the formed portion 3A to absorb the forming distortion generated when performing bending press working.

[0018] Figure 3 is bent indicates pressing previous stiffener 3, the bending line bending when extended to bent line L ₂ each side of the bending line L ₁ between the press during processing of the bending line L _1, L ₂ L _A substantially square opening 7 is formed by punching in a portion surrounded between the _two .

FIG. 4 shows a mold for bending press working, in which a die 8 on which the stiffener 3 is placed, a punch 9 which descends with respect to the die 8 and applies bending stress to the stiffener 3 on the die 8. A stripper 1 for holding the stiffener 3 in cooperation with the die 8 and lowering the punch 9 when the punch 9 is lowered.
0.

In the mold having such a configuration, when forming the molded portion 3A on the stiffener 3 by press working, the stiffener 3 is placed on the die 8 such that the adhesive 2 is on the upper surface, and a punch is formed. Lower 9 and stiffener 3
Bending is performed along the bending lines L ₁ and L ₂ .

According to the BGA type semiconductor device configured as described above, the opening 7 is formed at the four corners of the forming portion 3A of the stiffener 3 to absorb the forming distortion generated when performing bending press working. As described above, when the stiffener 3 is subjected to the bending press working, the molded portion 3A can be formed while securing the flatness even if the adhesive 2 is bonded to the stiffener 3 in advance. In other words, according to this configuration, the conditions under which the tensile stress and the compressive stress do not occur after bending are that the thickness of the material in the region (bending region) sandwiched between the bending lines L ₁ and L ₂ is reduced and the material in that portion is reduced. By clarifying the relationship between the required elongation, it is possible to easily grasp the relationship. Moreover, since the bending by press working is performed from the side of the adhesive 2 of the stiffener 3 as shown in FIG. 4, the surface of the die 8 and the stiffener 3 are sufficiently adhered to each other.
A flatter bending is possible.

[0022] Figure 5 is a second bent according to the embodiment shows a stiffener 3 before pressing, in two directions with a predetermined length orthogonal from the four corners of the sandwiched bending line L _1, L ₂ region of the present invention An L-shaped opening 7 is formed by punching.

In the structure of this embodiment, the bent portion is small and the residual stress is relatively small, so that a higher flatness can be obtained.

The BGA type semiconductor device according to the above-described embodiment is constituted by the stiffener 3 on which the adhesive 2 is applied in advance on one side for cost reasons, but the adhesive 2 is applied in advance. A similar effect can be obtained even if there is none.

[0025]

As described above, according to the BGA type semiconductor device of the present invention, the formed portion of the stiffener has a rectangular shape.
And the stiffener is formed by molding the molded part.
The opening for absorbing the molding distortion generated during
Since it is located at the corner, it is very easy to form an opening,
Significant cost reduction in construction can be achieved, and
The flatness of the product when molded can be reliably increased
You.

[Brief description of the drawings]

FIG. 1 is a perspective sectional view showing a BGA type semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a stiffener according to the first embodiment.

FIG. 3 is a plan view showing a stiffener before press forming according to the first embodiment.

FIG. 4 is a sectional view showing a mold used for press molding according to the first embodiment.

FIG. 5 is a plan view showing a stiffener according to a second embodiment of the present invention.

FIG. 6 is a perspective sectional view showing a conventional BGA type semiconductor device.

FIG. 7 is a perspective sectional view showing another conventional BGA type semiconductor device.

FIG. 8 is a perspective view showing a stiffener of another conventional BGA type semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 TAB tape 1A Polyimide film 1B Wiring pattern 2 Adhesive 3 Stiffener 3A Molding part 4 Semiconductor element 4A Bump 5 Sealing resin 6 Ball terminal 7 Opening 8 Die 9 Punch 10 Stripper

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor: Mamoru Mita 3-1-1, Sukekawacho, Hitachi City, Ibaraki Prefecture Inside the cable plant of Hitachi Cable Co., Ltd. (72) Inventor: Osamu Yoshioka, 3550 Kida Yomachi, Tsuchiura City, Ibaraki Pref. Hitachi Cable, Ltd. System Materials Research Laboratory (56) Reference: JP-A-9-55448 (JP, A) JP-A-9-22962 (JP, A) JP-A-6-196617 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 23/12 H01L 23/50

Claims (3)

(57) [Claims] 1. A BGA type semiconductor device comprising a semiconductor element disposed in a concave molded portion of a stiffener and connecting the semiconductor element and a wiring pattern disposed on a flat portion of the stiffener. A BGA type semiconductor device , wherein a forming part is rectangular, and the stiffener has openings at four corners of the rectangle, which absorb molding distortion generated when the forming part is formed. 2. The method according to claim 1 , wherein the stiffener is provided with a semiconductor element in the concave portion.
On the semiconductor element and the flat part of the stiffener.
BGA type configured by connecting the arranged wiring patterns
In the semiconductor device, the molded portion of the stiffener is rectangular,
Funa is a molding strain that occurs when molding the molded part.
Has openings for absorbing the four corners of the rectangle.
Formed over a predetermined length along the sides of the rectangle
A BGA type semiconductor device, characterized in that: 3. The semiconductor device according to claim 1 , wherein
And an adhesive layer is applied in advance to the surface on which the wiring pattern is to be placed.
3. The BGA according to claim 1, wherein said BGA has a structure attached to said BGA.
Type semiconductor device.