JPH0747868Y2 - Lead frame holder in chip bonding or wire bonding process - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a lead frame holder in a chip bonding or wire bonding process.

[Prior art]

Packaged semiconductor devices such as ICs are manufactured through processes such as chip bonding, wire bonding, resin mount, dam bar cut, register coat, marking, and lead plating. These processing steps are usually performed on a lead frame in which a large number of lead portions of the semiconductor device are continuously formed. The lead frame is a lead wire for supplying external drive power, signals, etc. to the semiconductor device,
It is integrally punched out from a thin plate, and is usually formed by forming frames for a large number of semiconductor devices in a continuous continuous manner into a long shape. During the above-mentioned processing steps of the semiconductor device, the chip bonding step is a step of fixing the semiconductor chip to a predetermined portion of the lead frame with an adhesive or solder, and
The wire bonding step is a step of connecting between the pad portion of the semiconductor chip fixed to a predetermined portion of the lead frame and the bonding portion of the lead frame. The chip bonding process and the wire bonding process are processes for electrically connecting a semiconductor chip such as an IC and a lead for supplying a signal etc. to the semiconductor chip, and therefore have a great influence on the most important reliability of the IC. . Therefore, very high processing accuracy is required. However, since the lead frame is formed by punching a very thin plate-shaped material into a complicated shape, it is easily deformed, and normally, in the chip bonding process and the wire bonding process, the lead frame is heated. Since it is often mounted on a support such as a heat block, thermal deformation easily occurs, and high-precision processing cannot be performed as it is. For this reason, a plate-shaped lead frame retainer provided with working holes is attached from above the lead frame placed on the support,
The wire bonding or the chip bonding is performed while fixing the lead frame.

[Problems to be solved by the device]

However, the plate-shaped lead frame retainer presses the lead frame planarly on the contact surface with respect to the lead frame other than the portion where the working hole is formed, and therefore, due to the surface accuracy of the plate-like lead frame retainer, It is difficult to completely press the lead frame. Further, since the lead frame is mounted on a heated support and the lead frame holder presses the lead frame in surface contact with the lead frame, the lead frame holder can be improved in accuracy even if the lead frame holder is improved in accuracy. The heat from the support is easily transmitted through the lead frame, and the lead frame itself is thermally deformed, so that the lead frame cannot be pressed with high accuracy. Therefore, the processing accuracy of chip bonding and wire bonding cannot be improved, and the reliability of semiconductor devices such as ICs cannot be improved. Further, in the case of the conventional plate-shaped lead frame holder, there is a problem in that the work hole cannot be enlarged because the complicated shape of the lead frame is pressed, and the workability of the chip bonding and wire bonding steps deteriorates. It was The present invention can solve the above-mentioned conventional problems, reliably press the lead frame, improve the processing accuracy of the chip bonding and wire bonding steps, and improve the workability of the above-mentioned processing steps. It is an object of the present invention to provide a lead frame holder in a bonding or wire bonding process.

[Means for Solving the Problems]

The present invention takes the following technical means in order to solve the above problems. That is, the invention of the present application, in a chip bonding step of bonding a semiconductor chip on a lead frame, or a wire bonding step of connecting between each pad of the semiconductor chip bonded on the lead frame and each bonding portion of the lead frame, A lead frame retainer for pressing and fixing each bonding portion of the lead frame against a support surface, wherein the frame portion is attached to a peripheral portion of an upper surface of the lead frame, and a cantilever plate independently of the frame portion. And a plurality of arm portions that extend in the shape of each of the bonding portions and that are in the vicinity of the bonding portions. Is integrally formed.

[Function and effect of device]

The frame portion of the lead frame holder according to the present invention is
It is attached to the peripheral portion of the upper surface of a lead frame mounted on a support such as a heat block so as to surround a processed portion where chip bonding or wire bonding is performed. On the frame portion, a plurality of arm portions extending from and extending to the vicinity of each bonding portion are integrally extended and formed, and on the rear surface of the tip end portion of the arm portion, the vicinity of each bonding portion of the lead frame is dotted. A pressing protrusion that elastically presses is integrally formed. In the conventional lead frame holder, the whole lead frame is fixed by planarly pressing it against the surface of the support. For this reason, if the plane accuracy of the lead frame holder is poor, it is not possible to uniformly press the entire lead frame. On the other hand, even if the plane accuracy is improved, warpage occurs due to the influence of heat, etc. There was a problem that the part would rise. In the lead frame holder according to the present invention, the pressing protrusion formed on the back surface of the tip of the arm portion elastically presses the vicinity of the bonding portion pointwise against the support, so that the influence of the heat of the support is exerted. Never receive. That is,
Since the arm portion is not in contact with the surface of the lead frame, heat is not directly transmitted from the lead frame, and the pressing projection formed on the back surface of the tip portion of the arm portion elastically contacts the lead frame. Since they are formed so as to be in contact with each other, even if the arm portion is deformed to some extent due to the influence of heat, the pressing protrusion at the tip portion can surely press the vicinity of the bonding portion of the lead frame with elasticity. In addition, since each pressing protrusion is provided at the tip of the arm portion that extends independently from the frame portion, a predetermined state can be achieved without being affected by the pressing state of the pressing protrusion that presses other portions of the lead frame. Each pressing point can be pressed with the pressing force of. Further, the arm portion can be formed by electrolytic processing or the like, can be manufactured with high accuracy, and can easily cope with a complicated lead frame. Moreover, since only the portion to be pressed can be pressed point by point, the overall pressing force for pressing the lead frame can be reduced, and the lead frame can be pressed and supported extremely efficiently. . Further, since the pressing projection presses the lead frame with an elastic force by elastically deforming the arm portion itself, the position and posture when attaching the lead frame pressing member like the conventional lead frame pressing member. It is not necessary to maintain high precision, the work is remarkably easy, and the mechanism for driving the lead frame holder is significantly simplified. In addition, in the lead frame holder of the present invention, since the frame portion and the arm portion are basically formed by removing a part of the plate material by etching or the like, the arm portion is formed from the frame portion. It can be extended to the vicinity of the bonding part to be pressed through an arbitrary path and can be formed to have a thickness necessary to obtain a pressing force. The opening can be made much larger. Therefore, workability in the chip bonding and wire bonding steps can be significantly improved. As described above, according to the present invention, the processing accuracy in the chip bonding process and the wire bonding process can be remarkably improved, the reliability of the semiconductor device can be dramatically improved, and the semiconductor device can be manufactured. The workability of work can be improved.

[Explanation of Examples]

An embodiment of the present invention will be specifically described below with reference to FIGS. 1 to 3. In this embodiment, the present invention is applied to a lead frame retainer used in a lead frame processing step for manufacturing an eight-segment LED as shown in FIG. FIG. 1 is a plan view showing a state in which a lead frame retainer 3 is attached from the upper surface of a lead frame 2 placed on a support 1. FIG. 2 is an enlarged sectional view taken along the line II-II in FIG. As shown in these figures, the lead frame 2 in this embodiment is composed of eight segment
Eight light emitting diode chips 4a corresponding to each LED segment are chip-bonded on the lead frame. As shown in FIG. 2, the lead frame 2 has an elongated shape with a substantially U-shaped cross section, and is connected to the outside on both sides of the lead forming portion 6 in which a large number of lead wires 5 are punched and formed. The terminal portion 7 for bending is formed by bending. Unit frames 2a corresponding to a large number of eight segments LED's are continuously formed in the longitudinal direction of the lead frame 2, and lead wires punched and formed in the lead forming portions 6 of the unit frames 2a. In order to prevent the pieces 5 from coming apart, the tip portions of the terminal portions 7 corresponding to the lead wires 5 on both sides of the lead forming portion 6 are continuously connected between the unit frames. In addition, the lead frame 2 is reinforced at the boundary of each unit frame 2a, and
An auxiliary frame 8 is formed for positioning during the machining. As shown in FIG. 1, the lead frame 2 has terminal portions 7 formed by bending both sides of the lead forming portion 6.
However, it is placed on the upper surface of the support 1 so as to straddle the support 1. In this embodiment, the supporting body 1 employs a long heat block 1a heated to a predetermined temperature for wire bonding, and the lead frame 2 slides on the upper surface of the heat block 1a. Thus, it is loaded and placed at a predetermined position on the heat block 1a. Now, the lead frame holder 3 according to the present embodiment is the first
As shown in FIGS. 2 and 2, it is formed of a rectangular plate-shaped material such as stainless steel and has an opening 9 formed inside, and an outer peripheral portion surrounding the opening 9 is a peripheral edge of an upper surface of each unit lead frame 2a. A frame portion 10 attached to the portion is formed. The opening 9 is formed with a large number of arm portions 11 extending integrally from the inside of the frame portion 10. The arm portion 11 cantilevers up to the vicinity of the bonding portion 12 of the lead forming portion 6 of the lead frame 2, while a pressing protrusion protruding toward the lead forming portion 6 is provided on the back surface of the tip of the arm portion 11. 13 are integrally formed. As shown in FIG. 2, the pressing protrusions 13 are provided in the vicinity of the bonding portion 12 of the lead forming portion 6 to which each light emitting diode 4a is fixed or which is connected to the pad portion 14 of each light emitting diode 4a. It elastically presses against the surface of the heat block 1a. The opening 9 of the lead frame retainer 3 according to this embodiment.
The arm portion 11 is formed by etching a stainless plate material. Therefore, the arm part 11 is elastically deformable by itself. In addition, a pressing protrusion 13 formed on the back surface of the tip of the arm portion 11
Means that the pressing protrusion 13 has a predetermined thickness on the back surface of the arm portion 11.
It can be integrally formed by notching by half etching except the tip portion forming the. In the lead frame retainer 3, a mounting shaft 17 formed at the lower end of a mounting bar 16 that vertically reciprocates on the side of the lead frame 2 is inserted into a mounting hole 15 formed on the side of the frame portion 10. , Is fixed to the mounting bar 16 by tightening the nut. Then, it descends corresponding to the lead frame 2 slidably fed on the heat block 1a, is attached to the upper surface of a predetermined unit lead frame 2a, and the tip of the arm portion 11 is the bonding portion 12 of the lead frame 2. While pressing and supporting the vicinity, the opening 9
A capillary or the like (not shown) is inserted into the wire, and wire bonding is performed. In the lead frame holder 3, a pressing protrusion 13 formed on the rear surface of the tip of the arm portion 11 integrally extending from the inside of the frame portion 10 has a heat block 1a in the vicinity of the bonding portion 12 of the lead frame 2. Since the point is elastically pressed against the point, it is not affected by the heat transmitted from the heat block 1a. That is, since the arm portion 11 does not contact the surface of the lead frame 2 except for the pressing protrusion 13 at the tip thereof, heat is not directly transmitted from the lead frame 2. Further, since the pressing protrusion 13 formed on the back surface of the tip portion of the arm portion 11 is formed so as to elastically contact the lead surface of the lead frame 2,
Even if the arm portion 11 is deformed to some extent by the influence of heat, the pressing protrusion 13 at the tip portion can reliably press the vicinity of the bonding portion 12 of the lead frame 2 with elasticity. In addition, since each pressing protrusion 13 is provided at the tip of the arm portion 11 extending independently from the frame portion 10, the pressing state of the pressing protrusion 13 that presses the other portion of the lead frame 2 is affected. It will not be done. Further, by changing the thickness and length of the arm 11, it is possible to reliably press each pressing point near the bonding portion 12 with a predetermined pressing force. Since the opening 9 and the arm 11 are formed by etching, they can be manufactured with extremely high accuracy, and it is possible to easily deal with a complicated lead frame. Moreover, since only the portion to be pressed can be pressed point by point, the overall pressing force for pressing the lead frame 2 can be reduced, and the lead frame 2 can be pressed and supported extremely efficiently. Becomes In addition, the pressing protrusion 13 has elasticity and is used for the lead frame 2.
Since the pressing of the lead frame holder 3 is performed, the accuracy of the pressing posture of the lead frame holder 3 itself such as the surface alignment with the processed surface of the lead frame 2 does not become a problem as in the conventional lead frame holder, and chip bonding or wire bonding is performed. The work is much easier. Furthermore, the arm portion 11 can be extended from the frame portion 10 to a vicinity of each bonding portion 12 of the lead frame 2 through an arbitrary path, and is required to obtain a pressing force for each arm portion 11. It is sufficient to form the opening 9 so that the opening 9 for processing the chip bonding or the wire bonding can be remarkably large as compared with the conventional lead frame holder. Therefore, workability in the chip bonding and wire bonding steps can be significantly improved. As described above, according to the present invention, the processing accuracy in the chip bonding process and the wire bonding process can be remarkably improved, the reliability of the semiconductor device can be dramatically improved, and the semiconductor device can be manufactured. The workability of work can be improved. The present invention is not limited to the above embodiments. Although the lead frame holder 3 is formed by etching in the embodiment, it may be formed by another manufacturing method.

[Brief description of drawings]

FIG. 1 is a plan view of a lead frame holder according to the present invention mounted on a lead frame, FIG. 2 is an enlarged sectional view taken along line II-II in FIG. 1, and FIG. 3 is a lead frame shown in an embodiment. Eight manufactured by applying a presser
It is an external perspective view of a segment / LED. 1 ... Support, 2 ... Lead frame, 4 ... Semiconductor chip, 10 ... Frame part, 11 ... Arm part, 12 ... Bonding part, 13 ... Press protrusion, 14 ... Pad.

Claims (1)

[Scope of utility model registration request] 1. A chip bonding step of bonding a semiconductor chip onto a lead frame, or a wire bonding step of connecting between each pad of the semiconductor chip bonded onto the lead frame and each bonding portion of the lead frame. A lead frame retainer that presses each bonding portion of the lead frame against the support surface to position and fix the lead frame, and a frame portion attached to the peripheral portion of the upper surface of the lead frame and a cantilever plate independent of the frame portion. While having a plurality of arm portions extending to the vicinity of each bonding portion, on the back surface of the tip end portion of each arm portion, a pressing protrusion that elastically presses the vicinity of each bonding portion in the lead frame pointwise. Chip bon, characterized by being integrally formed Lead frame holder in the bonding or wire bonding process.