JPS615531A - Semiconductor assembling device - Google Patents

Abstract

PURPOSE:To reduce position adjusting manual processes by a method wherein the position of the material to be pressure-bonded or the position of the pellet in an intermediate station is detected, and the operation of a bonding arm and a collet is controlled based on the information obtained by the above-mentioned detection. CONSTITUTION:Television cameras 20A and 20B (position recognition mechanism) are provided at the positions located above an intermediate station 4 and a bonding stage respectively, and the positional information of the pellet 2 on the intermediate station and the bonding stage are transmitted to a control circuit part 21 (positioning mechanism). The servo motors 21A and 21B controlled by the control circuit part 21 are connected to the cam 14D of an arm vertical movement driving part 14 and the cam 19d of an arm horizontal direction microscopic driving part 19, and the operation of the arm vertical movement driving part 14 and the arm horizontal direction microscopic movement part 19 is controlled by the control circuit part 21.

Description

[Detailed Description of the Invention] [Technical Field] The present invention can be effectively applied to a process of fixing a pellet onto a press-bonded body such as a lead frame in the assembly process of semiconductor devices such as transistors, ICs, and LSIs. Regarding technology.

[Background Art] As a device for fixing pellets onto a lead frame, the device shown in FIG. 1 can be considered.

That is, the pellets 2 arranged in a predetermined state on the tray 1 and supplied are held by the conveying arm 3, for example, by vacuum suction, and moved to the intermediate station 4, where they are moved by the positioning claws 5 provided at the intermediate station 4. It is positioned in a predetermined posture.

The lead frame 6 is aligned in a predetermined posture by a loader 7, and is sequentially moved to a bonding stage 9 by a conhair 8.
is transported and positioned.

At the intermediate station 4, the positioned pellet 2 is held by a collet 11 made of a highly hard material such as tungsten carbide, which is provided at the tip of the bonding arm 10, by vacuum suction, and then transferred to the bonding stage 9. It is transported to a predetermined position on the lead frame 6 positioned above.

The pellet 2 conveyed to a predetermined position on the lead frame 6 is pressed against the lead frame 6 by the collet 11 and subjected to minute vibrations. Forms crystals and becomes fixed.

The lead frame 6 to which the pellets 2 are fixed is conveyed to a conveyor 8
, and is recovered by the unloader 12 and sent to the next process.

By repeating the above series of Φ operations, the pellets 2 are fixed onto a large number of lead frames 6.

However, the inventors have found that the above-described device has the following drawbacks.

That is, the collet 11 that directly holds the pellet 2 is made of a highly hard material to provide wear resistance;
Since the pellet 2 is made of a fragile material such as Si crystal, if the position of the collet 11 deviates even slightly from the predetermined position when the collet 11 adsorbs and holds the pellet 2 at the intermediate station 4, the pellet 2 A large amount of force will be applied and damage will occur.

Also, in the bonding stage 9, the pellet 2
If the lead frame 6 is fixed to a position away from the predetermined position, it may cause trouble in subsequent processes, resulting in a decrease in product yield.

In order to prevent the above-mentioned inconvenience, it is conceivable to manually align the collet 11 at the intermediate station 4 and the bonding stage 9 before operating the device. High precision positioning is required, and the work requires great skill.
ta0. ,,yo. □
9, 3. □1 (7) (□) Even if the alignment work is carried out, it will not be possible to cope with changes in the position of the collet 11 due to wear and thermal expansion of various parts of the device while the device is in operation, and damage to the pellet 2 will occur. Yield loss cannot be avoided.

A detailed description of the bullet bonding technology can be found in PI 4, published by Kogaku Kenkyukai [Electronic Materials J, November 1981 special issue, November 10, 1981].
There are 9 to P155.

[Object of the Invention] An object of the present invention is to provide a semiconductor assembly technique that requires less manual positioning work and provides a good product yield.

Another object of the present invention is to provide a semiconductor assembly technique that allows accurate bonding of pellets.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Summary of the Invention] A brief overview of typical inventions disclosed in this application is as follows.

A position recognition mechanism detects an error in the position of the object to be pressed on the bonding stage where the pellet is fixed onto the object to be pressed, or an error in the position of the pellet at an intermediate station where the pellet is positioned, and transmits the detected error to the positioning mechanism.

The positioning mechanism operates the bonding arm and collet to hold the pellet at the intermediate station based on the above error, transport it to a predetermined position on the object to be crimped located on the bonding stage, and fix it to the object to be crimped. This is accomplished by correcting the positioning of the bonding arm and collet at the intermediate station or bonding stage.

[Embodiment] FIG. 2 is a front view schematically showing a semiconductor assembly apparatus which is an embodiment of the present invention.

A positioning claw 5 is provided at the intermediate station 4 to position the pellet 2.

The bonding stage 9 is connected to a conveyor 9 (not shown), and lead frames 6 (objects to be pressed) are sequentially supplied.

A collet 11 for holding the pellet 2 is provided at the tip of the bonding arm 10.

The bonding arm 10 includes a lever 13 and a spring 1.
3A to the plate 14A of the arm vertical movement drive unit 14.
vertical movement is transmitted.

The plate 14A of the arm vertical movement drive unit 14 is guided by a pair of guide bosses 14B, is movable in the vertical direction, is pressed against the cam 14D by a pair of springs 14C, and is moved in the vertical direction by rotation of the cam 14D. It has a structure that allows

The lever 13 is connected to a slide block 16 via an arm minute movement mechanism 15.

The arm minute movement mechanism 15 has a structure in which a slider 15A is movably fitted to a horizontal guide pin 15B, is pressed against a lever 18 by a spring 15C, and the horizontal position is adjusted by rotation of the lever 18. ing. .

The slide block 16 is guided so as to be horizontally movable by a bearing mechanism 17, is pressed against a cam 16B by a spring 16A, and is moved horizontally by rotation of the cam 16B.

One end of a lever 18 is brought into contact with the arm minute movement mechanism 15, and the lever 18 is rotatably supported by the slide block 16 by means of a pin 18/M.

The other end of the lever 18 is brought into contact with the plate 19A of the arm horizontal minute drive unit 19 by a spring 18B, and the plate 19A is guided by a pair of guide posts 19B to be movable in the vertical direction, and is moved by a pair of springs 19G. It has a structure in which it is pressed against the cam 19D and is moved in the vertical direction by rotation of the cam 19D.

Further, television cameras 20A and 20B (position recognition vIA structure) are provided above the intermediate station 4 and the bonding stage 9, respectively, and the position information of the pellet 2 at the intermediate station and the position information of the lead frame 6 at the bonding stage are transmitted to the control circuit. Part 21
(positioning mechanism).

Servo motor 21A controlled by control circuit section 21
, 21B are the cams 1 of the arm vertical movement drive section 14, respectively.
4D and the cam 19D of the arm horizontal minute drive unit 19
The operation of the arm vertical movement drive unit 14 and the arm horizontal micro drive unit 19 is controlled by the control circuit unit 21 .

Next, the operation of this embodiment will be explained.

Predetermined position of the pellet 2 at the intermediate station 4 and the lead frame 6 at the bonding stage 9
The predetermined position of is stored and held in the control circuit section 21.

The amount of rotation of the cam 19D of the arm horizontal minute drive unit 19 connected to the arm minute movement mechanism 15 via the arm 18 is adjusted so that the collet 11 can accurately hold the pellet 2 at a predetermined position in the intermediate station. The position of the cam 1.9D at that time is stored and held in the control circuit section 21.

Similarly, the lowering position of the collet 11 is also adjusted by rotating the cam 14D of the arm vertical movement drive section 14,
The position of the cam 14D at the proper lowering position of the collet 11 is stored and held in the control circuit section 21.

Further, in the bonding stage 9, the horizontal position and lowering position of the collet 11 when the slide frame 6 is in a predetermined position are also adjusted in the same way as in the intermediate station 4, and the cam 19D and The position of 14D is stored and held in the control circuit section 21.

Pellets 2 containing a large number of pellets 2, for example fed individually from a tray (not shown) to an intermediate station 4 by a conveyor 7-me (not shown), are positioned by positioning claws 5.

At this time, the television camera 20A detects the displacement of the positioned Perenote 2 from a predetermined position in the horizontal direction and the vertical direction, and transmits it to the control circuit section 21.

The slide block 16 is moved horizontally by the rotation of the cam 16B, and the arm 10 and the collet II provided at its tip are positioned at a predetermined position above the intermediate station 4.

At this time, the control circuit unit 21 determines the rotation angle of the cam 19D according to the horizontal displacement of the pellet 2, rotates the cam 19D via the servo motor 21B, and adjusts the horizontal position of the collet 11. A match is made.

Next, the control circuit 21 lowers the collet 11 by rotating the cam 14D via the servo motor 21A, and the pellet 2 is held on the collet 11 by, for example, vacuum suction.

At this time, the rotation angle of the cam 14D is corrected in accordance with the change in the vertical position of the pellet 2 from the predetermined position, and the collet 11 is brought to an appropriate lowered position.

As described above, since the horizontal and vertical positions of the collet 11 are adjusted in accordance with changes in the position of the pellet 2 positioned at the intermediate station 4, damage to the pellet 2 caused by the collet 11 at the intermediate station 4 is prevented. Prevented.

The collet 11 holding the semiconductor pellet 2 is raised to a predetermined position by rotating the cam 14D.

The slide block 16 is moved horizontally by the rotation of the cam 1jB, and the collet 11 holding the pellet 2! The lead frame 6 is placed on the bonding stage 9.
is positioned at a predetermined position on top of the

A deviation of the lead frame 6 from a predetermined position on the bonding stage 9 is detected by the television camera 2OB and transmitted to the control circuit section 21.

The control circuit section 21 rotates the cam 19D via the servo motor 21B according to the magnitude of the deviation of the lead frame 6, and the collet 11 holding the pellet 2 fixes the pellet 2 on the lead frame 6. It is located directly above the desired position.

Next, the control circuit section 21 rotates the cam 14D via the servo motor 21A, the collet 11 is lowered, and the pellet 2 held by the collet 11 is accurately fixed at a predetermined position on the lead frame 6. It will be done.

1. The above series of operations are repeated one after another, and a large number of pellets 2 are bonded to the lead frame 6.

[Effects] (1) The position of the collet in the intermediate station where the collet holds the pellet and the bonding stage where the pellet is fixed to the object to be pressed is automatically adjusted in response to changes in the position of the pellet and the object to be crimped. This reduces the amount of work needed to manually adjust the position of the collet.

(2) According to the above (11), the pellet holding operation by the collet at the intermediate station becomes accurate and breakage of the pellet is prevented.

(3) According to the above (11), the position where the pellet is fixed to the object to be pressed in the bonding stage is accurate, and the number of defective fixations is reduced.

(4) According to (3) above, the size of the portion of the press-bonded body to which the pellet is fixed can be reduced, so that the semiconductor device can be miniaturized.

(5) As a result of (2) and (3) above, the yield in the bonding process is improved.

(6) As a result of (1) to (5)♀, the productivity in the bonding process is improved.

Although the invention made by the present inventor has been specifically explained based on Examples, the present invention is not limited to the above-mentioned Examples, and may be modified in various ways without departing from the gist thereof. Needless to say.

For example, in FIG. 2, it is also possible to perform the position adjustment operation in a direction perpendicular to the paper surface.

[Field of Application] In the above explanation, the invention made by the present inventor was mainly applied to the field of application which was the background of the invention, that is, attaching a belet to a lead frame. It can also be widely applied to attaching pellets to ceramic packages, etc.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view of essential parts of a possible semiconductor assembly device, and FIG. 2 is a schematic front view showing a semiconductor assembly device that is an embodiment of the present invention. 2...Bellet, 4...Intermediate station, 5...
・Positioning claw, 6...Lead frame (body to be crimped),
9... Bonding stage, 10... Bonding arm, 11... Collet, 13... Lever, 1
3A... Spring, 14... Arm vertical movement drive unit, 15
...Arm minute movement mechanism, 16...Slide block, I7...Bearing mechanism, 18...Lever, 1
8A... Pin, 18B... Spring, 19... Arm horizontal minute drive unit, 20A, 20B... TV camera (position recognition mechanism), 21... Control circuit unit (positioning mechanism), 21A, 21B... Servo motor (positioning mechanism).

Claims (1)

[Claims] 1. Recognizing at least one of the position of the object to be pressed in a bonding stage where the pellet is fixed to the object to be pressed, or the position of the pellet at an intermediate station where the pellets are individually supplied in a predetermined posture. a position recognition mechanism and holding a pellet located at the intermediate station;
It is characterized by having a positioning mechanism that controls the operation of the bonding arm and collet that are conveyed to the object to be crimped located on the bonding stage and fixed at a predetermined position on the object to be crimped, based on information from the position recognition mechanism. Semiconductor assembly equipment. 2. The positioning mechanism rotates a cam via a servo motor in accordance with the horizontal and vertical positional deviations of the pellet and the object to be crimped recognized by the recognition mechanism, and adjusts the horizontal and vertical positions of the collet. 2. The semiconductor assembly apparatus according to claim 1, further comprising a control circuit section for adjusting the position in the vertical direction.