JPH0153506B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a carrier tape for supplying lead wires for semiconductor integrated circuit (IC) devices.

Wire bonding is generally used to connect electrodes on IC elements and external leads, but in recent years, in order to automate the mounting of IC elements,
Carrier tapes such as the one shown in the figure have come to be used.

This carrier tape has sprocket holes 2 on both edges of a metal foil tape 1 made of copper, iron, iron-nickel alloy, etc. with a thickness of about 200 μm or less and a finger which is an aggregate of a plurality of fine leads 3 in the center. A method in which multiple sets of leads are formed continuously in the longitudinal direction and the surfaces are coated with gold, tin, etc. as necessary, and the inner leads of these fingers are overlapped with the electrodes on the IC element and bonded all at once. Many
It is used to attach IC elements to the tape, then cut the outer leads all at once and connect them to the required external leads. At that time, the sprocket hole 2 is used for positioning during the above-mentioned batch bonding and batch cutting.

Basically, conventional continuous photo etching can be applied to manufacture such carrier tape, but
The tape is extremely thin compared to normal materials, so special consideration is required. For example, in the case of normal materials,
First, a sprocket hole is prepared and this can be used for tape feeding and exposure alignment, but if this method is applied to metal foil tape, the sprocket hole 2 will deform, making it impossible to accurately bond the IC elements all at once. . For this reason, the metal foil tape has been fed using pinch rollers. However, this method has the disadvantage that the latent image pattern is deformed because the exposed photoresist is pressed with a roller in a precise pattern, and the required patterns for sprocket holes and finger leads are deformed when developed. . To solve this problem, as in the method described in U.S. Pat. No. 4,227,983, it is possible to use a metal foil tape with a width wider than the required carrier tape width and feed it by pinching the margin with a grip roller. good. However, when continuously exposing a metal foil tape coated with photoresist, positioning is performed using grip roller feeding and roller guides, which results in uneven distances between each pair of sprocket holes and finger leads. Or, unevenness in direction is likely to occur.
This is due to the feed accuracy of the grip roller and the clearance between the roller guide and the metal foil tape. If the distances and directions between the sets are too large, when IC elements are bonded together, the positions of the IC elements may be slightly corrected by the sprocket hole 2, but the IC elements will be bonded during the process of correction. The only way to avoid this is to lengthen the time required for bonding alignment.

The present invention eliminates these conventional drawbacks and provides a method for manufacturing a carrier tape in which the directions of the sprocket hole pattern and the finger lead pattern are precisely aligned and the distance between each set is constant. It is something to do. An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram for explaining one embodiment of each step in the method for manufacturing the carrier tape of the present invention,
7 to G are cross-sectional views showing how the metal foil tape changes. As shown in FIG. 2, the metal foil tape 4 used has a width that allows alignment through holes to be formed on both sides of the required width of the carrier tape (Step A). This metal foil tape 4 is first press-worked to form through holes 5 at regular intervals on both edges of the tape (Step B). The tape 4 is fed by a grip roller or the like, but if positioning pins are provided in the post-process of the press mold, the distance between the through holes 5 and the deviation in the width direction of the tape can be minimized.

Next, a photoresist 6 is applied to both sides of the tape 4 by the required width of the carrier tape (step C).
There are two types of photoresists: negative type and positive type, but as long as an exposure mask suitable for either type is used, either type can be used. Then, the metal foil tape 4 coated with the resist 6 is exposed on both sides using a required mask, and latent images of the sprocket hole pattern 7 and the finger lead pattern 8 are formed on the resist layer (Step D). After exposure, only the exposed or unexposed resist is dissolved and removed (referred to as development; step E), and when the etching solution is sprayed from both sides, the exposed metal parts are melted and penetrate through the front and back sides (step F). At this time, both edges of the tape where no resist is applied are completely dissolved. After etching,
By removing the remaining photoresist 6, a carrier tape 9 as shown in FIG. 1 is obtained (Step G).
It is wound up at the end of the series of steps described above.

The above steps may be performed continuously, or may be performed for each step or divided into several steps. Note that among the above steps, the pressing step and the exposure step require intermittent feeding, but when these steps are performed in a continuous process, the metal foil tape may be slackened before and after each step.

In the above example, one carrier tape is manufactured from a metal foil tape. However, in order to simultaneously manufacture multiple carrier tapes, a metal foil tape that is wider than the width of multiple carrier tapes is used, and during exposure, a width direction A photomask may be used which has a plurality of sets of sprocket hole patterns and finger lead patterns, and a slit pattern for separating each set. It is also possible to expose a plurality of sets of sprocket hole patterns and finger lead patterns in the longitudinal direction of the tape in one exposure.

As explained in detail above, according to the present invention, it is possible to manufacture a carrier tape in which the distance and direction between each pair of sprocket holes and finger leads are precisely aligned, which improves bonding speed and reduces bonding defects. It has a big effect.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a carrier tape, and FIG. 2 is an explanatory diagram showing an example of each step in the method for manufacturing the carrier tape of the present invention. 4...Metal foil tape material, 5...Sprocket hole, 6...Photoresist.

Claims (1)

[Claims] 1. A method for manufacturing a carrier tape in which sprocket holes are continuously formed on both edges of the tape and multiple sets of finger leads are continuously formed in the center, using a metal foil tape wider than the required tape width as the material. , Through holes are formed at regular intervals on both edges of the metal foil tape by press punching, photoresist is applied to both sides of the carrier tape by the required width, alignment is performed using the through holes, and a sprocket hole pattern and a sprocket hole pattern are formed. After exposing the finger lead pattern on both sides and removing only the exposed or unexposed resist,
A method for manufacturing a carrier tape, characterized by etching exposed metal parts and finally removing residual resist. 2. The method for manufacturing a carrier tape according to claim 1, wherein in the double-sided exposure step, a plurality of sets of sprocket hole patterns and finger lead patterns are simultaneously exposed in the longitudinal direction of the metal foil tape. 3. In a method for manufacturing a carrier tape in which sprocket holes are continuously formed on both edges of the tape and multiple sets of finger leads are continuously formed in the center, a metal foil tape having a width wider than the required number of tapes is used as the material, Through-holes are formed at regular intervals on both edges of the metal foil tape by press punching, and then photoresist is applied to both sides by the width of multiple carrier tapes.
Align using the through holes, and expose multiple sets of sprocket hole patterns, finger lead patterns, and separation slit patterns between each set in the tape width direction on both sides, and expose or unexposed to light. A method for manufacturing a carrier tape, characterized in that after only the resist is removed, the exposed metal part is etched, and finally the remaining resist is removed so that a plurality of tapes can be obtained at the same time. 4. The method for manufacturing a carrier tape according to claim 3, wherein in the double-sided exposure step, a plurality of sets of sprocket hole patterns and finger lead patterns are simultaneously exposed in the longitudinal direction of the metal foil tape.