JPS6036101B2 - pellet bonder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pellet bonding method and a pellet bonder used therein.

Conventionally, the bullet bonding method using epoxy resin involves applying epoxy resin to the board in advance, placing the pellet on the epoxy resin using a collet or tweezers, and bonding by rubbing it. It is frequently used in the assembly process of electronic components such as semiconductor devices.

However, this type of material has poor bondability and problems with electrical and thermal characteristics.

Conventionally, when applying epoxy resin on a board,
Screen printing methods, potting methods, stamping methods, etc. are used, but these methods have various drawbacks as detailed below, making it difficult to apply a fixed amount of epoxy resin to a substrate with a fixed film thickness. This is due to this.

That is, in the screen printing method, a silk-like screen is provided on a substrate, the mesh is roughened only in necessary areas, and epoxy resin is printed from the top surface.

Therefore, the adjustment of the coating thickness is delicate, and since the coating thickness cannot be made very thin, there are disadvantages in that the epoxy resin also adheres to the pellet surface during bonding. on the other hand,
In the potting method, a syringe-like needle is connected to a tank-like case containing epoxy resin, and the epoxy resin is sprayed onto the substrate from the tip of the needle using air pressure.

Therefore, when discharging epoxy resin from the needle tip (0.2 to 0.3 ribs) using air pressure, it is difficult to maintain a constant amount of epoxy resin, and clogging of the needle tip and air bubbles cause dry blowing. Moreover, according to this method, it is applied in an owan shape. Further, the stamping method is performed by pressing a prismatic stamp-like rod onto an epoxy resin film, and then pressing it onto a substrate to transfer the epoxy resin onto the substrate.

Therefore, when transferring and adhering the epoxy resin onto the substrate, the pressing force of the stamp-shaped ridges is delicately adjusted and difficult to control. SUMMARY OF THE INVENTION Therefore, the present invention aims to provide a new bullet bonding method with excellent bondability such as bonding strength, and a bullet bonder that can be used directly with the method, thereby obtaining a device with excellent electrical and thermal characteristics. It is something. In order to meet these objectives, the present invention provides a pellet bonding method in which the pellet is pressed against a substrate with epoxy resin adhered to the back surface of the pellet in advance, and the pellet bonding method used in this method is such that the pellet is bonded by a collector. While transporting the pellet onto the substrate, the collet is lowered onto the epoxy resin film to adhere the epoxy resin to the back surface of the pellet, and then the collet holding the pellet is raised and transported onto the substrate, and the collet is moved onto the substrate. It is a type of material that can be rubbed and bonded. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a pellet bonding method used for assembling a semiconductor device, which is a preferred embodiment of the present invention, and a pellet ponder used therein will be specifically described with reference to the drawings.

In the pellet bonding method according to the present invention, a fixed amount of epoxy resin 2 is adhered to the back surface of a pellet 1 on which a semiconductor element is provided, and the epoxy resin 2 is vacuum-adsorbed by a collet 3. The pellet 1 is pressed onto the substrate 4 to perform bonding using the epoxy resin 2 as a fixing material.

In this case, the moving path of the collet 3 (the pellet housing jig 5
A plate (table) 6 with a flat surface is installed at the lower part of the way (transfer route from the substrate 4 to the substrate 4), an epoxy resin film 2a having a constant thickness is supplied to the surface, and the collet 3 is placed there. If the epoxy resin 2 is applied to the back surface of the pellet 1 by lowering it, the present invention can be carried out very easily (see FIGS. 1 a to 1 d). Second
The plan view shown in the figure and the side view shown in FIG. 3 are a pellet bonder constructed based on the idea of the present invention.
In the figure, reference numeral 3 denotes a collet, which has a square pyramidal recess at its lower end, vacuum-suctions the bellet, and is attached to a bonding arm (not shown) that can move back and forth and up and down. The beret bonder according to the present invention includes a collet 3 attached to a bonding arm that can move forward, backward, upward, and downward, a spare table 7 for holding a storage pick-up 5 that accommodates a beret, and a beret 1 made of epoxy resin 2. It consists of a table 8 on which a substrate 4 to be fixed is placed, and an epoxy resin supply body 9 provided at an intermediate position between the storage jig 5 and the table 8.

On the other hand, to explain the epoxy resin descendant combination 9 mechanism as shown in FIGS. 4 and 5, the supply block 12 fixed to the movable table 11 moves in the direction of arrow A.

This supply block 12 includes a window hole 13 for supplying the epoxy resin 2 and an escape hole 14 when the collet 3 descends and presses the held bullet against the epoxy resin film 2a. Approximately 5cc of epoxy resin 2 is placed in the window hole 13.
The window hole 14 has walls 15 at both ends that allow the epoxy resin 2 to form a certain epoxy resin film 2a on the table 8.

Further, although not shown in the drawings, the supply block 12 is configured such that its height relative to the table 8 can be controlled to vary the thickness of the epoxy resin film 2a. Next, bullet bonding using this bullet bonder will be explained.

First, the collet 3 is advanced and then lowered to attract the pellet 1 on the accommodation jig 5 to the suction portion on the lower surface of the collet 3.

Thereafter, the collet 3 is raised, retreated, and lowered, and the pellet 1 is pressed against the epoxy resin film 2a formed on the table 8 below the escape hole 14 while maintaining the suction state. At this time, the epoxy resin 2 is formed on the entire back surface of the pellet 1 due to the surface tension of the epoxy resin film 2a. The collet 3 holding the beret moves up, retreats, and descends again while in the adsorbed state, and presses or rubs the beret onto the substrate 4 on the table 8 to fix it. On the other hand, the epoxy resin film 2a on the table 8 of the epoxy resin supply body 9 is transferred to the back surface of the pellet when the pellet is pressed, so that no epoxy resin film 2a remains.

Then, the supply block is moved onto the table 8 and a new epoxy resin film 2a is formed on the wall 15. Further, the accommodation jig 5 and the substrate 4 are moved one pitch at a time to perform the pelleting operation one after another. Then, the collet 3 performs the operation of suctioning and holding a new pellet 1 by repeating rising, advancing, descending, and retreating again. The configuration of the present invention makes it possible to supply and adhere a constant amount of epoxy resin to the back surface of the pellet with a constant thickness, which is effective in improving adhesive strength.

[Brief explanation of the drawing]

1A to 1D are cross-sectional views for explaining the pellet bonding method according to the present invention, FIG. 2 is a plan view showing the pellet bonder according to the present invention, FIG. 3 is a side view thereof, and FIG. 5 is a plan view of the epoxy resin supply body, and FIGS. 5 a to 5 b are front views thereof. 1...Bellet, 2...Epoxy resin, 3...Collet, 4...Substrate, 5...
...Accommodating jig, 6...Plate (table) with a flat surface, 7...Spare table, 8...
...Taffle, 9...Epoxy resin supply body, 11...Moving table, 12...Supply block, 13...Window hole, 14... ...Escape hole, 15... Wall. Figure 1, Longevity Z diagram, Figure 3, Longevity diagram, 4th diagram, System 5 diagram.

Claims (1)

[Claims] 1 A collet that transports pellets to a predetermined position and presses the pellets against a substrate for bonding, and an epoxy resin that supplies epoxy resin onto a plate with a flat surface provided below the collet's movement path. The pellet is temporarily lowered while the pellet is being conveyed, and the epoxy resin on the plate with the flat surface is attached to the back side of the pellet, and then the pellet is pressed against the substrate using the collet, and the pellet is placed on the back side of the pellet. The epoxy resin supply body has a supply block that is reciprocated on the flat surface plate, and this supply block is provided with the epoxy resin. a window hole through which the collet can enter, an escape hole through which the collet can enter, and a wall disposed between the window hole and the escape hole to form a predetermined gap between the surface of the plate and the surface of the plate;
Due to the action of the wall as the supply block reciprocates, the epoxy resin supplied from the window hole is spread onto the surface of the plate at a position below the escape hole to a thickness corresponding to the gap. A pellet bonder characterized by being configured to form a resin film.