JPH03198360A - Bonding tool - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention uses TAB mounting (gear bonding).

[Prior Art] Conventionally, as a method for mounting semiconductor elements, a gear bonding method, which is capable of bonding a plurality of lead terminals at once, has been generally adopted as a method that is highly mass-producible and highly reliable.

TAB mounting (gear bonding) has the advantage that the work can be done all at once, regardless of the number of lead terminals. This is a method in which bumps (electrodes) are formed on a semiconductor element, and the bumps and lead terminals are bonded by heat and pressure using a bonding tool while positioning the lead terminals of the film carrier from above.

The bonding tool has a tool body (
23) into the heater insertion hole (20) and thermocouple insertion hole (2).
1), and a tip (22) of a high hardness material such as diamond is fixed to the tip end surface of the crimping part.

The tool body is made of metal alloy such as stainless steel, and the tip is heated by a heater (not shown) fixed in the heater insertion hole of the tool body, and the electrode part of the semiconductor element and the film carrier are heated. The temperature of the heater is optimally controlled by a thermocouple.

Diamond chips are used for crimping surfaces because of their excellent wear resistance and non-conductivity, but they are very expensive, so artificial diamonds are used for boat fishing. Furthermore, recently, in addition to diamond chips, there are also bonding tools in which a diamond film obtained by CVD or the like is formed on the pressure bonding surface. However, in such conventional bonding tools, when the electrodes of the semiconductor element and the lead terminals of the film carrier are bonded by thermocompression, when the bonding tool is heated to about 600 degrees Celsius by a heater, the bonding tool body Warpage, peeling, etc. will occur on the tool pressure bonding surface due to the difference in thermal expansion coefficient between the diamond tip and the diamond chip or diamond coating.

As a result, the electrodes of the semiconductor element and the lead terminals of the film carrier cannot be properly bonded, resulting in defects.

The present invention provides a bonding tool to overcome the aforementioned drawbacks.

[Means for Solving the Problems] In order to solve the above problems, the present invention uses a conductive heat transfer part (heating and heat generation part) made of SiC at the tip of the bonding tool, and a diamond coating on the crimping surface. is formed.

[Operation] By using the bonding tool with the above configuration, the tip of the bonding tool when heat-pressing the bumps on the semiconductor element and the lead terminals of the film carrier can have a coefficient of thermal expansion that is almost the same as that of the diamond film, Since the conductive heat transfer portion is made of SiC with high adhesion, there is no difference in thermal expansion with the diamond film, and the bonding and fixation can be ensured.

Furthermore, since it has good thermal conductivity, it can sufficiently cope with instantaneous heating during bonding.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

A first embodiment of a multi-bin bonding tool according to the present invention is shown in FIG. In the figure, (1) is the bonding tool body, (2) is the shank part, (3) is the heat insulation/insulation part, (4) is the SiC conductive heat transfer part (hereinafter referred to as SiC heat transfer body), (5) is a diamond film, (6) is a Si
C It is an electrode attached to a heat transfer body. The bonding tool (1) is made of an alloy of metals such as stainless steel, and the shank part (2) has a heat insulating/insulating part (3) on the bonding tool body (1) and a SiC heat transfer body ( 4), Diamond ff1 (5
) and are joined and fixed by means such as brazing.

Moreover, here, the central portion of the SiC heat transfer body is made into a convex shape, and the state is shown in which it is press-fitted into the heat insulation/insulation part (3). After polishing and grinding the SiC heat transfer body (4) to form a bonding surface, the diamond film (5) was formed to a thickness of approximately 3 to 10 μm using the existing CVD method.

Furthermore, two electrodes (6) (7) are attached to the SiC heat transfer body (4).
) is inserted and fixed and attached by means such as screwing, brazing, or gluing, and current is applied to each electrode via a lead wire (not shown) to heat it.

The heat insulation/insulation part (3) is provided to concentrate the heat generated by the SiC heat transfer body (4) to the diamond coating (5) at the tip, and is mainly made of ceramic material. Further, the SiC heat transfer body (4) uses single crystal and polycrystalline SiC, and the impurities contained in the SiC are 20
PPM or less is good.

FIG. 2 shows a second embodiment of the present invention of a bonding tool for multiple pins. After joining and fixing the shank part (2), heat insulating/insulating part (3), and SiC heat transfer body (4) by brazing or other means as in the first embodiment, polishing and grinding are performed to form a diamond coating. formed. The electrodes (8) and (9) are adhesively fixed to the SiC heat transfer body. FIG. 3 shows a third embodiment of a single point bonding tool. The heat insulating/insulating part (3) and the SiC heat transfer body (12) are bonded and fixed to the tip of the shank part (10) of the bonding tool by brazing or the like in the same way as in the first and second embodiments, and then bonding is carried out. Forms a diamond film on the surface.

Electrodes (6) and (7) are provided on the SiC heat transfer body (12).

Furthermore, by forming the groove (11) in the center of the SiC heat transfer body (12), the diamond coating (5), that is, the bonding surface, can efficiently generate heat.

FIG. 4 shows a bonding tool in a pulse heat tool, which is a fourth embodiment of the present invention.

The tool body (15) is made of a metal alloy such as stainless steel, and has a groove (17) formed in the center and left and right shank parts (
It is divided into 13) and (14). A SiC heat transfer body (16) having a groove extending from the same position as the groove (17) of the tool body (15) is attached to the tip thereof by brazing or other means, and the bonding surface is coated with a diamond film ( 5) is provided.

The SiC heat transfer body (16) is heated by the tool body (1
In order to directly send current to the shank portions (13) and (14) of 5), the shank portions (13) and (14) serve as electrodes.

The grooves formed on the SiC heat transfer body (16) are for efficiently heating the diamond coating, as in the third embodiment.

FIG. 5 shows another embodiment of the bonding tool according to the present invention. (25) is a SiC heat transfer part, (5) is a diamond film, (24) is a heater insertion hole, (
3) is the heat insulation/insulation part. The SiC heat transfer part and the diamond film (5) are formed in the same manner as in the first to fourth embodiments, and the heat insulation/insulation part (3) and the SiC heat transfer body (25) are formed in the same manner as in the first to fourth embodiments.
A heater insertion hole is made in between. Since there is a heat insulating/insulating section on the top of the heater (not shown), almost all of the heat generated by the heater (not shown) can be transferred to the SiC heat transfer section, allowing efficient bonding.

Furthermore, thermocouples (not shown) are attached to the SiC heat transfer bodies of the first to fifth embodiments to control the thermal temperature during bonding.

[Effects of the Invention] As described above, the bonding tool of the present invention has a diamond film formed on the SiC heat transfer body, so that when the electrode on the semiconductor element and the lead of the film carrier are bonded under heat and pressure, the bonding tool of the present invention has a diamond coating on the SiC heat transfer body. Since the difference in thermal expansion between the heat transfer body and the diamond coating is almost the same, there is no possibility of warping of the tool tip or peeling of the diamond coating, which not only improves productivity, but also improves productivity. This produces effects such as being able to efficiently transmit heat to the bonding surface during heating.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a third embodiment of a multi-pin bonding tool of the present invention. The $2 figure is the second
FIG. 3 is a new view showing the embodiment, and FIG. 3 is a sectional view of the third embodiment showing a single point bonding tool. FIG. 4 is a front view of the fJ4 embodiment showing a bonding tool for pulse heat. FIG. 5 is a sectional view of another embodiment of the bonding tool according to the present invention. Figure fJ6 is a sectional view showing the structure of a conventional multi-bin bonding tool on which a diamond film is formed. 1 −−−−−−−−− 2 −−−−1−−−− 3−1−−−−−−− 4・ 12 ・ 5−・−−1−・− 6・ 7 ・ 8 24 ・・−・− Bonding tool body shank part heat insulation/insulation part 16/25・−・−−−−−− Diamond film ・9−−−−−−−・ Electrode heater insertion hole SiC heat transfer body + Fig. For evening funerals

Claims (2)

[Claims] (1) In a bonding tool that thermocompresses an electrode on a semiconductor element and a lead terminal, a conductive heat transfer part made of SiC is provided at the tip of the bonding tool, and the electrode is fixed to the conductive heat transfer part and crimped. A bonding tool characterized by having a diamond film formed on its surface. (2) In a bonding tool for thermocompression bonding an electrode on a semiconductor element and a lead terminal, a conductive heat transfer part made of SiC is provided at the tip of the bonding tool, and a diamond film is applied to the crimping surface of the conductive heat transfer part. A bonding tool characterized in that a heater is placed at the other end of the bonding tool.