JPS62159438A - Heat block for die bonder - Google Patents

Abstract

PURPOSE:To prevent leads from being discolored by disposing projections having flat upper surfaces in response to the positions of tabs of a lead frame on the contacting surface of a heat block for a die bonder with the lead frame. CONSTITUTION:Projections 3a or 3b having flat upper surfaces are disposed in response to the positions of tabs of a lead frame on the contacting surface of a heat block 1 for a die bonder with the lead frame. Accordingly, the lead frame is not contacted with the heat block except the portions of the tabs. As a result, the lead frame is preferentially heated at the portions of the tabs. Therefore, it can prevent loads from being discolored.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a heat block for a die bonder. More specifically, the present invention relates to a heat block for a die bonder, which has a protrusion with a flat upper surface on the contact surface with the lead frame, corresponding to the position of the tab of the lead frame.

[Conventional technology] Another name for a transistor or IC pellet is a chip.

Or call it Dai. In diffused-type transistors such as mesa and brainer transistors, the die itself is usually the collector, so you can connect it to the collector by attaching the die to the collector lead or stem.

This is so-called die bonding. Die bonding methods include a eutectic alloy method, a conductive adhesive method, a soldering method, and a glass method. What these methods have in common is that the die bonding work is performed at a high temperature of about 200°C to 600°C. Heat blocks for die bonders have traditionally been used for this die bonding work.

[Problems to be Solved by the Invention] As shown in FIG. 2, the die bonder heat block 10 can be moved up and down by the shaft portion 14 that is movable up and down. A cartridge heater 18 that is powered by a conductor 16 is disposed in the die bonder heat block 10 . The lead frame 20 is moved from the left direction to the right direction in the drawing. The heat block 10 moves up and down every time the lead frame 20 is pitch-fed,
At the top dead center, the heat block contacts the lead frame 20, conducts the heat of the heat block to the lead frame, and heats the lead frame.

However, in the conventional heat block 10 for a die bonder, the contact heating surface 12 with the lead frame 20 is formed in a planar structure. For this reason, the lead frame 20 has tabs 22
The other entire surfaces of the leads 24 are in contact with the heating surface 12 of the die bonder heat block. As a result, the contact portion of the lead frame (particularly the lead portion 24) may become discolored. Such discoloration causes the wire to separate from the lead immediately during wire bonding, which has various adverse effects on the next process, reducing not only the manufacturing yield of semiconductor devices but also the reliability of ICs.

[Object of the Invention] Therefore, an object of the present invention is to provide a heat block for a die bonder that does not cause discoloration of the lead frame adhesive portion.

[Means for Solving the Problem] As a means for solving this problem, the present invention provides a heat block for a die bonder that has an upper surface on the contact surface with the lead frame, corresponding to the position of the tab of the lead frame. To provide a heat block for a die bonder, characterized in that a flat protrusion is provided.

[Function] As described above, according to the heat block for a die bonder of the present invention, discoloration of the lead portion is effectively prevented because it comes into contact with the lead frame only at the location corresponding to the position of the tab on the lead frame. can. As a result, the possibility of an inconvenient situation occurring in a process after die bonding is reduced, and throughput is improved. Furthermore, the manufacturing yield of semiconductor devices and the reliability of ICs are also improved.

[Example 1] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partial perspective view showing an embodiment of the heating surface in contact with a lead frame of a heat block for a die bonder according to the present invention.

As shown in FIGS. 1(a) and 1(b), the contact surface with the lead frame of the heat block 1 for a die bonder of the present invention has a
A protrusion 3a or 3b having a flat upper surface is provided.

Therefore, the lead frame contacts the die bonder heat block only at the tab portion. As a result, the tab portion of the lead frame is heated preferentially.

As shown in Fig. 1(a), the width of the protrusion with a flat upper surface disposed on the contact surface with the lead frame of the heat block for die bonder is approximately the same as the width of the tab of the lead frame. or, alternatively, as shown in Figure 1 (b
), it may be wide enough to contact the tab of the lead frame and the side edge 26 (see FIG. 2) of the lead frame.

The heat processor for a die bonder of the present invention has a protrusion with a flat upper surface on the heating surface in contact with the lead frame, but the other structure and operation are similar to those of the conventional heat processor as shown in FIG. The structure and operation can be almost the same as that of the heat block for a die bonder.

[Effects of the Invention] As explained above, according to the heat block for a die bonder of the present invention, discoloration of the lead portion can be effectively prevented because the heat block for a die bonder of the present invention comes into contact with the lead frame only at the locations corresponding to the positions of the tabs on the lead frame. It can be prevented. As a result, the possibility of inconvenience occurring in the process after die bonding is reduced, and throughput is improved. Furthermore, the manufacturing yield of semiconductor devices and the reliability of ICs are also improved.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view showing an embodiment of the contact surface of a heat block for a die bonder according to the present invention with a lead frame. FIG. 2 is a conceptual perspective view of a conventional heat block for a die bonder.

Claims (3)

[Claims] (1) A heat block for a die bonder, characterized in that a protrusion with a flat upper surface is provided on the contact surface of the heat block with the lead frame, corresponding to the position of the tab of the lead frame. (2) The heat block for a die bonder according to claim 1, wherein the width of the flat upper surface of the protrusion is approximately the same as the width of the tab of the lead frame. (3) The die bonder heat according to claim 1, wherein the flat upper surface of the protrusion is wide enough to contact the tab of the lead frame and the side end of the lead frame. block.