JPS6257098B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for mounting a semiconductor chip on a substrate, and in particular, to a device for mounting a semiconductor chip on a substrate. The present invention relates to a mounting device used in the so-called face-down bonding method, in which a chip is electrically and mechanically attached directly to a connection point by overlapping it and soldering it.

Various types of devices are available for mounting semiconductor chips on substrates, but they can be roughly divided into optical devices using a half mirror and devices that combine a TV camera and a numerical control device/electronic computer.
When using such conventional equipment to mount large semiconductor chips such as VLSIs, the former is viewed from an angle, which tends to cause misalignment due to parallax, and alignment is difficult during work. There are elements that depend on the patient's patience, and the disadvantage is that the yield is poor.

Examples of the latter include those disclosed in Japanese Patent Publication No. 52-21671,
This device generates an image of a semiconductor chip and also generates a boundary marker that indicates the boundary of the edge position of the semiconductor chip when mounted on a substrate, and compares the two image signals. In order to ensure that the edge of the semiconductor chip is adjacent to the edge of the boundary marker but does not overlap, the object is moved until these video signals no longer match.

Although this method allows relatively accurate positioning, boundary markers must be set according to the shape of the semiconductor chip to be mounted, and it is not suitable for high-mix, low-volume production.

The semiconductor chip mounting device according to the present invention includes:
This was done in view of the above-mentioned difficulties, especially in the face down bonding method.
A transparent tray is attached to the Y positioning device in the shape of a canopy and has a plurality of semiconductor chips placed thereon, a first TV camera is provided with a lens facing the bottom surface of the tray, and a horizontal direction from the X and Y positioning device is provided. a substrate platform having an X, Y, θ positioning device provided at a distance from the substrate platform, an X, Y, θ fine adjustment manipulator attached to the X, Y, θ positioning device, and a top surface of the substrate platform. a second TV camera provided with lenses facing each other; and a second TV camera that moves reciprocally between the tray and the substrate mounting section and the first and second TV cameras.
It is equipped with a vacuum suction conveyance device that moves up and down on the optical axis of the TV camera, and a monitor device that combines and displays images from the first and second TV cameras, and the substrate mounted on the substrate mounting section. By making fine adjustments using the X, Y, and θ fine adjustment manipulators and matching the connection points in the image of the bottom surface of the semiconductor chip picked up by the vacuum suction transport device with the image of the top surface of the board, the precision of the board and semiconductor chip can be adjusted. It is characterized by accurate positioning.

Hereinafter, details of the present invention will be explained with reference to the drawings. FIG. 1 is a front view showing one embodiment of a semiconductor chip mounting device according to the present invention, and FIG.
FIG. 3 is a partial plan view of the figure. Reference numeral 1 denotes a frame for mounting various components of the apparatus, and a semiconductor chip positioning and mounting mechanism 10 is provided on this frame 1. The positioning and mounting mechanism 10 consists of an An X, Y, θ positioning device is provided horizontally apart from the TV camera 16 and X, Y positioning device 12 of No. 1, and has a substrate mounting section 17 at the upper end for placing a substrate on which a semiconductor chip is mounted. 18, substrate mounting section 17
A second lens 21 is provided on the upper surface of the
TV camera 22, tray 11 and board mounting section 1
7, and also moves up and down on the optical axis of the first and second TV cameras.
It is composed of 4. Furthermore, frame 1 includes a monitor TV 31, first and second TV cameras, camera controllers 32 and 33 for controlling the monitor TV 31, a synchronization signal generator 34,
A monitor device 30 consisting of a synchronization signal distributor 35 and a video mixer 36 is provided. 37 is a power source.

A method for mounting a semiconductor chip using the mounting device configured as described above will be explained in more detail with reference to FIG. FIG. 3 is a functional diagram of the mounting device, in which a semiconductor chip 41 to be mounted on a substrate 40 is placed on the tray 11 with the bumps 42 facing downward. As shown in FIG. 4, the tray 11 is constructed by placing an appropriate transparent plate 11b on a frame 11a, and further placing semiconductor chips 4 on top of the transparent plate 11b.
The three members are fixed by overlapping thin plates 11d in which chip positioning holes 11c into which chips 1 can be inserted are formed in a grid pattern. This tray 11 is
It is placed directly above the perforation 12b (the perforation is sized to be inscribed in the frame 11a of the tray 11) of the tray support plate 12a attached to the tray support plate 12a in the form of an eave. Next, the X-direction drive motor 13 and the Y-direction drive motor 14 of the X, Y positioning device 12 are driven to move the desired semiconductor chip 41 directly below the suction tool 24a of the vacuum suction transport device 24. The X, Y positioning device 12 is driven by known numerical control or the like. The desired semiconductor chip 41 is positioned, that is,
When positioned on the axis of the TV camera 16 and suction tool 24a, a motor (not shown) built into the vacuum suction conveyance device 24 moves the hollow cylindrical shape through a rack-pinion (not shown), for example. The suction tool 24a is lowered until it comes into contact with the semiconductor chip 41. When the suction tool 24a reliably contacts the semiconductor chip 41, the vacuum pump 27 is activated via a flexible pipe 27a connected to the hollow cylinder of the suction tool 24a, and the semiconductor chip 41 is moved onto the suction tool 24a.
adsorbs to. The suction tool 24a that has suctioned the semiconductor chip 41 rises, returns to the initial position, and stops. The first TV camera 16 photographs the semiconductor chip 41 in this state from below (the surface with the bumps 42) and displays it on the monitor TV 31. The half mirror 28 holds the chip 4 sucked by the suction tool 24a.
1, and refracts light from a light source in the lateral direction to the chip 41. On the other hand, the second
The TV camera 22 has an X, Y, θ positioning device 18
The board 40 placed on the upper board rest 17 is photographed from above (the side with the connection terminals), and the monitor TV 3
Display on 1. 23, the TV camera 22 is
This is a micro positioning mechanism for fine adjustment in the direction. On the monitor TV 31, video signals from both TV cameras 16 and 22 are combined into an image by a video mixer 35 and displayed. If the bumps 42 in both of the combined images do not match the connection terminals (not shown) on the board 40, manually move the X, Y, θ fine adjustment manipulator 19 connected to the X, Y, θ positioning device 18 to Adjust until 42 and the connection terminal match. Such a manipulator 19 is known. Reference numeral 20 denotes a motor that can be started by a suitably provided switch, and when the fine adjustment of the manipulator 19 cannot fully adjust the motor, θ
(Rotation of the substrate platform 17) is adjusted by the motor 20.
This is done via a worm attached to the shaft of the board and a worm gear (both not shown) attached under the substrate mounting section 17. By adjusting the X, Y, θ positioning device 18, the bump 42 and the substrate 4
When the connection terminals 0 and 0 are completely aligned, the vacuum suction transfer device 24 is moved onto the substrate platform 17, the suction tool 24a is lowered, and the semiconductor chip 4 is placed on the substrate 40.
Mount 1. Normally, the connection terminals of the board 40 are coated with adhesive for temporary fixing, so the board 40 that has been mounted can be taken out from the board rest 17 by hand. The movement of the vacuum suction conveyance device 24 is carried out by a lead screw 26a connected to the shaft of a motor 26 on a positioning table 25, and a nut (not shown) attached to the bottom of the conveyance device 24 and screwed into the lead screw 26a. ).

The semiconductor chip mounting device according to the present invention has been described above based on one embodiment thereof, but since this mounting device images the substrate and the mounting surface of the semiconductor chip from the vertical direction, misalignment occurs due to parallax. Moreover, since the configuration is relatively simple in that the final positioning is performed by X, Y, and θ fine adjustment manipulators, there are no restrictions on the size and shape of the semiconductor chip and substrate to be mounted. Furthermore, since no special software is required to control the device, it is easy to handle and can be said to be an excellent device suitable for high-mix, low-volume production.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing an embodiment of a semiconductor chip mounting device according to the present invention, FIG. 2 is a plan view taken along the - arrow in FIG. 1, and FIG. A schematic diagram showing the functions of the mounting device, and FIG. 4 is an enlarged perspective view of the tray. 12...X, Y positioning device, 11...Tray, 16...First TV camera, 17...Substrate mounting section, 18...X, Y, θ positioning device, 22...
...Second TV camera, 24...Vacuum suction conveyance device, 30...Monitor device.

Claims (1)

[Claims] 1. A transparent tray that is attached to the X, Y positioning device in the form of a canopy and on which a plurality of semiconductor chips are placed;
A first lens provided on the bottom surface of the tray with lenses facing each other.
a TV camera, a substrate platform having an X, Y, θ positioning device provided horizontally apart from the X, Y positioning device, and an X, Y positioning device attached to the X, Y, θ positioning device. , a θ fine-adjustment manipulator, a second TV camera having lenses facing each other on the top surface of the substrate platform, and a second TV camera that moves back and forth between the tray and the substrate platform and the first and second TV cameras. comprising a vacuum suction conveyance device that moves up and down also on the optical axis of the TV camera, and a monitor device that combines and displays images of the first and second TV cameras,
The substrate placed on the substrate mounting section is
Accurate positioning of the substrate and the semiconductor chip is achieved by making fine adjustments using a fine adjustment manipulator and matching each connection point in the image of the bottom surface of the semiconductor chip picked up by the vacuum suction transport device with the image of the top surface of the substrate. Features of semiconductor chip mounting equipment.