JPH0153507B2 - - 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 many 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 in bulk. IC of
It is used to attach the 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 alignment in 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 provided and this can be used for tape feeding and exposure alignment, but when this method is applied to metal foil tape, the sprocket hole 2
is deformed, making it impossible to accurately perform bulk bonding of IC elements. For this reason, the metal foil tape has been fed using pinch rollers. However, this method has the drawback that since the photoresist exposed in a precise pattern is pressed with a roller, the latent image pattern is deformed, and when developed, the required patterns for sprocket holes and finger leads are deformed. Ta.

To overcome these drawbacks, U.S. Patent No.
As in the method described in No. 4227983, a metal foil tape with a width wider than the required carrier tape width is used as the material,
All you have to do is pinch the margins with a grit roller before sending. However, when continuously exposing a metal foil tape coated with photoresist, if positioning is performed using the grip roller feed and roller guide, the distance between each set of sprocket holes and finger leads may be uneven. , directional irregularities are 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, photoresist 6 is applied to the entire surface of both sides of this tape 4 (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. The metal foil tape 4 coated with the resist 6 is exposed on both sides using a required mask, and a sprocket hole pattern 7, a finger lead pattern 8, and a slit pattern on both outsides of the sprocket hole pattern 7 are formed on the layer of the resist 6. A latent image No. 9 is formed (Step D). After exposure, the exposed or unexposed resist is dissolved and removed (this is called development. Step E), and if the etching solution is sprayed from both sides, the exposed metal parts will be dissolved and penetrate through the front and back sides (F).
process). After etching, the remaining photoresist 6 is removed, and the tape on the parts having the press through holes 5 on both sides is separately wound and separated.
becomes a carrier tape as shown in Figure 1 (G
process).

Each of these steps may be performed consecutively, or
It 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. Furthermore, the order of steps (B) and (C) in the above steps may be changed. That is, first, a photoresist 7 is applied to both surfaces of the metal foil tape 4, and then through-holes 5 are formed at regular intervals on both edges of the tape by pressing. Even if this is done, there is no problem in alignment for exposure, and the through hole 5
Since the inner surface of the through hole 5 is not covered with the resist 6, both surfaces are etched in the etching step (F) and the diameter of the hole is enlarged, but this does not matter since the through hole 5 is no longer needed. Furthermore, it is easily understood that the resist coating in step (C) above may not be applied to the entire surface, but may be applied to a slightly wider area than the required width.

The above example describes the case where 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 the multiple carrier tapes is used, and during exposure, the width direction A photomask may be used which has a plurality of sets of sprocket hole patterns, finger lead patterns, and separation slit patterns between each set and on both outsides of the sprocket hole patterns.

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 set of sprocket holes and finger leads are precisely aligned, which greatly improves bonding speed and reduces bonding. effective.

[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. After performing the steps of forming through holes at regular intervals on both edges of the metal foil tape by press punching, and applying photoresist to the entire surface of the tape or to a width wider than the required width and both sides, the through holes are After aligning the resist using a photoresist, exposing a sprocket hole pattern, a finger lead pattern, and a separation slit pattern on both sides of the sprocket hole pattern, and removing only the exposed or unexposed resist. A method for manufacturing a carrier tape, comprising: etching exposed metal parts, removing residual resist, and finally separating both edges. 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, After performing the step of forming through holes at regular intervals on both edges of the metal foil tape by press punching and the step of applying a photo resistor to the entire surface of the tape or to a width wider than the required width and on both sides, the through holes are and exposing multiple sets of sprocket hole patterns, finger lead patterns, and separation slit patterns between each set and on both outsides of the sprocket hole patterns in the tape width direction,
After only the exposed or unexposed resist was removed, the exposed metal parts were etched, the remaining resist was removed, and finally both edges and multiple pieces of carrier tape were separated so that multiple pieces could be obtained at the same time. Method of manufacturing carrier tape. 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.