JPS6114873B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adhesive coating device suitable for applying adhesive by stamping when bonding a semiconductor element or the like to a package or the like.

In general, when stamping adhesives, the stamp tool can be adapted to any shape that corresponds to the shape of the element (material to be adhered).
The film thickness of the adhesive attached is also relatively stable,
and uniform. For stamping, press the stamp tool against the adhesive layer in the adhesive reservoir from above, pull up the stamp tool with the adhesive adhered to the stamp surface, and stamp the stamp surface on the package surface to which the element is fixed and bond it. This is done in a series of steps to attach the agent to the package surface. However,
This stamping is caused by the stringing phenomenon of the adhesive, that is, when the stamp tool is pressed onto the adhesive layer and then pulled up, and when the stamp tool is pulled up after being stamped on the package surface, the stamp surface of the stamp tool and the adhesive layer and package surface are It is known that a phenomenon occurs in which thread-like adhesive is formed to connect the adhesive attached to the material. The effects of this stringing phenomenon on the device mount manufacturing process are as follows. ○ Adhesive may protrude outside the stamping area, causing defects in package sealing in subsequent processes. ○B A relatively large amount of adhesive concentrates on the threaded part, making it impossible to obtain a uniform stamp film thickness. ○C Contaminate the outside of the device. ○D. A large amount of adhesive is consumed, making it uneconomical.

Therefore, in order to introduce and adapt stamping to the mass production process, it is necessary to take measures such as preventing this adhesive stringing phenomenon or cleaning the thread-like adhesive. This becomes a factor that complicates the structure of the machine and reduces the reliability of the device. It is desirable to prevent the stringy phenomenon itself from occurring.

The cause of the stringing phenomenon appears to be problems with the viscosity characteristics of the adhesive used for stamping and the structure of the stamp tool. Therefore, when we consider the stamping state when stamping is performed using a conventional general stamp tool 1 as shown in Fig. 1, including the results of experiments, we find that the stringing phenomenon is affected by the stamping operation as shown in Fig. 2. In the step of sequentially applying the adhesive to the adhesive application surface 26, the adhesive 23 crawls up to the side wall surface 22 of the stamp tool 1 in a prismatic shape and adheres to a part 23 around the side wall surface 22 in a concentrated manner. It has been found that this tends to occur from adhesive parts that have been deposited and accumulated. The adhesive stringing phenomenon shown in FIG. 2 occurs after 200 stamping operations using a conventional stamp tool. This is an example in which the stringing phenomenon 25 appears particularly frequently, and it is impossible to apply this stamping to mass production in consideration of the effects of the stringing phenomenon described above on other products.

The present invention was developed in view of the above points, and it is possible to reduce the stringing phenomenon even in stamping using a relatively high viscosity epoxy adhesive, thereby reducing the viscosity characteristics of conventional adhesives. The limited range of applicable adhesives used to be narrow, but now it is possible to expand this range, and in addition, it is possible to efficiently obtain a stamp area that matches the bonding surface of the material to be bonded and a uniform stamp film thickness. The present invention provides a chemical coating device.

Next, a first embodiment of the device of the present invention will be described with reference to FIG.

In the figure, 30 is a stamp body, for example, a prismatic stamp tool 1, and this stamp tool 30
As the material, it is preferable to select aluminum or SUS, which have a high degree of surface corrosion resistance. A support part, for example, a cylindrical support body 31 is integrally attached to this stamp tool 30 to be attached to a tool holder 43 (FIG. 4) of a stamping device, and the stamp tool 30 is connected to the surface 47 of the stamp tool 30 to which the adhesive is applied. Contact surface 3
The ridge line 35 and the side wall surfaces 32 and 34 of No. 3 are coated with a water-repellent coating such as a fluorine-based resin. Further, the contact surface 33 is processed to be a smooth surface. This smooth surface is a bell surface or a matte surface, and preferably has a surface roughness of, for example, 6S to 0.05S.

Next, the stamping operation by the stamping apparatus shown in FIG. 4 will be explained. The stamp tool 1 is mounted on a tool holder 43 of the device 42. Adhesive is poured into the adhesive reservoir 44 to a certain depth in advance. The contact surface 33 of the stamp tool 30 is held parallel to the adhesive layer 45 and lowered vertically from above into the adhesive reservoir 44, and stamped with a constant pressure for a certain period of time to adhere to the contact surface 33. agent 45
Attach. Thereafter, the stamp tool 1 is pulled up vertically at a constant speed. Next, the stamp tool 1 with the adhesive 45 adhered to it is moved horizontally to a position directly above the package 47, which is the adhesive application surface that is positioned and fixed at another position, and then lowered vertically to the surface of the package 47. The adhesive is attached to the surface of the package 47 by applying a stamp with a constant pressure for a certain period of time. Next, the stamp tool 30 is vertically pulled up to a fixed position at a constant speed, and then moved horizontally and stopped above the adhesive reservoir 44, where it is attached to the stamp ring
End the cycle.

In such a stamping operation using the stamp tool of the present invention, the threading phenomenon of the adhesive when pulling up the stamp tool 30 after stamping on the package surface is caused by the creeping up of the adhesive. This is reduced by being reduced by the surface coating portion 34 of the stamp tool side wall surface 32. That is, the surface coating portion 34, which forms a water-repellent coating such as a fluorine-based resin, has a releasing effect on the adhesive and prevents the adhesive from creeping up and accumulating during repeated stamping operations. In addition, by making the stamp surface 33 a smooth surface, the adhesive can be evenly attached to the stamp surface, providing a uniform film thickness without being concentrated in one part, and also preventing local stringiness. Glue build-up is reduced and when it is so effective. Furthermore, by limiting the viscosity range of the adhesive used for stamping and appropriately selecting the stamp pressing pressure, pulling speed, etc., the stringing phenomenon can be more reliably prevented.

Next, another embodiment of the present invention will be described with reference to FIGS. 5 and 6. The stamp tool according to this embodiment is provided with a chamfered portion 53 having an appropriate inclined surface or curved surface on each ridge line 35 where the contact surface 33 of the first embodiment intersects with both sides of the outer peripheral side wall surfaces 32 and 34. Similar to the first embodiment, the chamfered portion 53 and the outer peripheral side walls 32 and 34 are subjected to surface coating treatment, and a thin film layer 54 of fluorine resin or the like is provided. That is, this embodiment is similar to the first embodiment in that a water-repellent coating is formed near the ridgeline (boundary line with the chamfered portion 53) of the contact surface 33. The length of the chamfered portion 53 in the direction perpendicular to the stamping surface 51 is determined by the length of the adhesive layer 4 shown in the description of the stamping operation of the first embodiment (FIG. 1).
If the film thickness dimension of No. 5 is a, then approximately 1.5a to 5a is appropriate. When this stamp tool is used, the amount of adhesive creeping up into the stamp tool is further reduced compared to the first embodiment, which is highly effective in preventing the stringing phenomenon. Furthermore, it is clear that the range of application of the stamping tool to various adhesives can be expanded by forming an appropriate pattern within the stamp surface with the water-repellent coating as shown in the application example of FIG.

Since the water-repellent coating may be formed at least on the portion where the adhesive creeps up, it is sufficient to form the water-repellent coating on at least the side surfaces near the ridgeline (including the ridgeline).

Furthermore, by forming a water-repellent coating 71 in a strip shape on the peripheral edge of the contact surface 33 as shown in FIG. 7A, the stringing phenomenon can be reduced even when the viscosity is higher.

Furthermore, water repellent coatings 72 and 73 are applied to the contact surface 33.
It may also be provided inside as shown in FIG.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional stamp tool, Figure 2 is a perspective view of a conventional stamp tool.
The figure is a process state diagram of the stamp tool and adhesive after stamping as shown in Fig. 1, Fig. 3 is a perspective view of the stamp tool for explaining an embodiment of the device of the present invention, and Fig. 4 is the stamping operation shown in Fig. 3. 5 is a perspective view of the modification of FIG. 3, and FIG. 6 is a diagram showing the relationship between the stamp tool and the adhesive layer of the modification of FIG. 4. FIG. 7 is a top view of the stamp surface in an applied example of the stamp tool of the present invention. 30... Stamp tool body, 32, 34...
Side wall surface and surface covering portion, 33... opposing surface, 53...
...Stamp tool chamfer.

Claims (1)

[Scope of Claims] 1. A stamp body having an opposing surface that is in contact with an adhesive-applied surface, and a water-repellent coating formed on a side surface of the stamp body at least near the ridgeline of the opposing surface of the stamp body. An adhesive application device comprising: 2. The adhesive coating device according to claim 1, wherein the water-repellent coating is a fluororesin. 3. The adhesive coating device according to claim 1, wherein the water-repellent coating is made of Si (silicon) resin.