JPS634355B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to lead frames.

Generally, when assembling semiconductor products such as transistors and integrated circuits (ICs), a metal ribbon-shaped lead frame is formed by punching and shaping the desired pattern by chemical etching or press processing, and a continuous line is placed on the lead frame. A method of assembling is used.

An example of such a lead frame is one having a structure as shown in FIG. 1, for example.

However, in this lead frame structure, each frame unit of the lead frame includes a lead part 1 for electrical connection (in this example, the outer leads are omitted for simplicity and only the inner leads are shown), and a semiconductor chip. A tab 2 that constitutes a pellet mount section for attaching pellets, and a tab hanging lead 3 that mechanically supports this tab 2.
Each lead part 1 is electrically connected to the pellet by a wire (not shown), and such a lead frame unit connected part has, for example, 5 parts as shown in FIG.
The frames are simultaneously formed in one row in the length direction. That is, this lead frame has a single-strand structure.

Therefore, when assembling semiconductor products using such lead frames, the working capacity is limited by the single frame structure, and the assembly process in particular has the highest working speed compared to other processes. Since the assembly process is slow, it would be extremely inefficient to determine the production capacity by this assembly process.

Therefore, in order to improve the work capacity, it may be proposed to prepare one device for each series of lead frames and perform assembly work in parallel, but in this case,
Since multiple devices are required, problems such as extremely high equipment costs arise, and this is not a fundamental solution.

The present invention was made in order to solve the above-mentioned problems all at once, and its purpose is to obtain good productivity with low equipment costs.

In order to achieve this object, the present invention fixes a large number of semiconductor pellets in a lead frame formed by shaping a single metal plate into a desired pattern.
A lead frame for assembling semiconductor products for electrically connecting the electrode portion of each fixed semiconductor pellet to the lead portion of a lead frame and packaging each semiconductor pellet. A plurality of lead frame units each including a tab for fixing and a lead part for electrically connecting an electrode of a semiconductor pellet to be fixed to the tab are formed in series, The lead frame unit is characterized in that a plurality of continuous parts are integrally formed in parallel.

The present invention will be further described below with reference to embodiments shown in the drawings.

FIG. 2 is a plan view showing an embodiment of a lead frame according to the present invention.

As is clear from FIG. 2, this is an example in which the frame unit series is configured into two series, and the first frame series (unit series) 10A and the second frame series (unit series) 10B are arranged in the longitudinal direction. It is formed by integrally punching out two rows. In this example, each frame series 10A, 10B is composed of frame units for 5 frames, and each frame unit includes lead parts 11A, 11B, tabs 12A, 12B for attaching pellets, and tabs 12A, 12B.
Tab hanging leads 13A, 1 that mechanically support the
3B, and the electrode portion of the pellet attached to each tab 12A, 12B is electrically connected to each lead portion 11A, 11B by a wire (not shown).

Therefore, when the lead frame of this embodiment is used, the constituent materials of the lead frame remain as usual, and only a part of one device, such as a mold in the case of a resin mold or a head part of an assembly device, can be used as a part. By simply making changes, it is possible to obtain twice the working capacity compared to the example shown in FIG. In other words, as shown in Figure 2, 2
When manufacturing a semiconductor device using a continuous lead frame, after attaching a pellet to the tabs 12A, 12B by die bonding, each electrode portion of the pellet and each lead portion 11A, 11B are attached.
are electrically connected with wires using wire bonding, the lead frame is packaged using a resin molding method, etc., and the semiconductor device is manufactured by cutting and molding the lead frame into individual packages. can be carried out with twice the working capacity of a series of lead frames by changing only a part of the equipment.

For example, by die bonding, the tabs 12A of the two series of lead frames (unit series),
The work of attaching the pellets onto the pellets 12B will be explained based on FIG.
It has a double collet structure to match. That is, this double series consists of a first collect 14A and a second collect 14B, and each collect 1
4A and 14B hold pellets 15A and 15B for attachment to tabs 12A and 12B, respectively. The distance l between each collet 14A and 14B is the same as the distance l between the tabs 12A and 1 of the frame series 10A and 10B.
It is selected to match the pitch of 2B.

Therefore, in the example shown in FIG. 3, the two pellets 15A and 15B are collected by the respective tabs 12 by the collets 14A and 14B of the double collet structure.
It is possible to attach pellets A and 12B at the same time, and double the die bonding capacity can be obtained in one pellet attaching time compared to a single pellet structure.

In addition, each lead part 1 is
1A and 11B to each electrode part of the pellets 15A and 15B, the wire bonding machine head and the position memory part have a double structure, so that two frame chains (unit chain parts) 10 can be connected.
Wire bonding can be performed on both A and 10B at the same time.

Similarly, for packaging such as resin molding and cutting and molding of packages, it is possible to double the working capacity by using a dual structure of molds and the like.

In addition, although the above-mentioned example explained the lead frame structure of two series, the present invention is not limited to two series,
It can be implemented as a multi-unit structure with three or more units, in which case a part of the device may be partially modified, such as a three-unit collect structure, in accordance with the number of lead frames, and the frame unit connection part may be It does not necessarily have to be for 5 frames.

Furthermore, the lead frame of the present invention is not limited to the illustrated example, and can be applied to various semiconductor devices using various lead frames.

As described above, according to the present invention, it is possible to significantly improve the productivity of semiconductor devices and to significantly reduce equipment costs.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing a single lead frame structure, FIG. 2 is a schematic plan view showing a double lead frame structure according to an embodiment of the present invention, and FIG. 3 is a schematic plan view showing the lead frame structure of FIG. FIG. 3 is a schematic cross-sectional view showing a state in which die bonding is performed. 10A, 10B...Frame connection, 11A, 11
B...Lead part, 12A, 12B...Tab, 14
A, 14B...collect, 15A, 15B...pellet.

Claims (1)

[Claims] 1 Fixing a large number of semiconductor pellets in a lead frame formed by shaping a single metal plate into a desired pattern, electrically connecting the electrode part of each fixed semiconductor pellet to the lead part of the lead frame,
and a lead frame for assembling semiconductor products for packaging each semiconductor pellet, the lead frame electrically connecting tabs for fixing each semiconductor pellet and electrodes of the semiconductor pellet to be fixed to the tabs. A lead comprising a plurality of lead frame unit connecting parts formed in series, and a plurality of the lead frame unit connecting parts being integrally formed in parallel. flame.