JPH0622983Y2 - Semiconductor element mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a mounting device for semiconductor pellets, and more particularly to a mechanism for preventing erroneous mounting work.

[Conventional technology]

The conventional mounting device does not detect the clogging of the collet but only detects the pellet adsorption error.The method of detecting the pellet adsorption error is to detect the pellet adsorption port downward after the pellet adsorption operation until the pellet is mounted. The vacuum sensor is attached to the suction line by using the optical method of receiving the light emitted from the collet at the upper end of the collet and detecting the light / dark state of the pellet with / without the vacuum adsorption of the pellet. There is a method to detect it by the ON / OFF signal of, and in the unlikely event that a pellet adsorption error occurs, a mechanism is installed to prevent the collet from descending to the mount island in the lead frame.

[Problems to be solved by the invention]

As the above-mentioned conventional mounting device performs many mounting operations, deformation of the pellet suction port at the tip of the collet,
Adhesion of pellet scraps or solder causes clogging of the pellet suction port at the collet tip, or a phenomenon similar to clogging, and it is determined that there is pellet despite a mistake in pellet suction. There was a drawback.

Further, the vacuum sensor has a problem in stability, and both the optical system and the vacuum sensor system have a drawback that they are erroneously determined even when there is an abnormality such as disconnection or short circuit.

[Means for solving problems]

The semiconductor device mounting apparatus according to the present invention comprises a lamp fixed to be located between a pellet and a lead frame on which the pellet is mounted and emitting light, and a second lamp mounted on the first stage and performing a vertical movement. A collet having a light receiving element and a pellet suction port and fixed to the second stage, the collet moving between the semiconductor pellet and the lead frame together with the movement of the first stage; A shield plate fixed to the first stage, and when the collet moves to adsorb the semiconductor pellets and passes through the lamp, is shielded by the shield plate to generate a first timing signal; After the collet has performed the semiconductor pellet adsorption operation, it moves to mount the adsorbed semiconductor pellets and re-mounts on the above lamp. A sensor for generating a second timing signal by being shielded by the shielding plate when passing through, and determining whether the light receiving element receives light from the lamp through the pellet suction port of the collet. Detecting clogging of the pellet suction port by checking in response to a timing signal, and checking whether the light receiving element receives light from the lamp through the pellet suction port, in response to the second timing signal. Is used to detect an adsorption error of the semiconductor pellet.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of an embodiment of the present invention, FIG. 2 is a schematic view of a collet portion, and FIGS. 3 (A), (B), and (C) are normal mounting and collet clogging. FIG. 7 is a diagram showing the movement of the collet at the time of pellet adsorption error. In this embodiment, the first
The second stage and the second stage will be referred to as the Y stage and the Z stage, respectively. The collet 1 is attached to a Z stage 4 that moves up and down mounted on a Y stage 3 mounted on an X stage 2. A phototransistor 5 is attached to the upper end of the collet 1, and a lamp that is constantly lit. 6 is attached to the X stage 2 so that the position in the Y direction of the pellet suction port 7 of the collet 1 always matches, and when the position of the pellet suction port 7 of the collet 1 is positioned above the lamp 6, the photo interface A shield plate 9 that shields the raptor 8 from light is attached to the Y stage 3.

The pre-operation collet 1 is almost at the position shown in FIG. 1, and when it is normal, the X and Y stages 2 and 3 move first and the collet 1 moves as shown in FIG.
Is shielded once by the shield plate 9, outputs the signal 13, and outputs the signal 13
The instant the photo transistor 5 changes from dark to bright, the phototransistor 5 receives the light from the lamp 6 and is in a bright state. Then collet 1
Moves downward because it adsorbs pellets 10, adsorbs pellets 1 and ascends, and mount island 1 in frame 11
2 Moves upward, and the photo interrupter 8 is shielded again to output a signal 14 in the middle thereof. At the moment when the signal 14 changes from bright to dark, the phototransistor 5 is shielded by the pellet adsorbing the light of the lamp 6 and is in a dark state. Has become. Next, the collet 1 descends and rises due to the pellet mounting, and one sequence is completed.

Next, when the collet clogging occurs, as shown in FIG. 3 (B), the collet 1 is moving forward due to the adsorption of pellets. The instant phototransistor 8 when the signal 13 of the photo interrupter 8 changes from dark to bright. No. 5 is in a dark state because it does not receive the light from the lamp 6, and it is determined by this signal 15 that the collet is clogged. Thereafter, the collet 1 is not moved up and down and the collet 1 is returned to the initial position to display an alarm display. Stop doing.

Next, when there is no collet clogging and a pellet adsorption error occurs, as shown in Fig. 3 (C), the collet 1 performs the pellet adsorption operation and then mounts the adsorbed pellets.
While moving above the mount island 12 in the frame 11, the moment the signal 14 of the photo interrupter 8 changes from dark to bright, the photo transistor 5 receives the light of the lamp 6 and is in a bright state. When it is determined that the pellet suction is wrong, the pellet suction operation is performed again without performing the mounting operation. When the pellet suction failure is detected three times in a row, an alarm is displayed and the operation is stopped.

[Effect of device]

As described above, the present invention can prevent the occurrence of pellet-less products due to solder sticking and collet clogging due to pellet scraps by performing the pellet adsorption error detection and the collet clogging detection within one mount sequence. By adjusting the sensitivity of the phototransistor, it is possible to detect even if the pellet suction port at the tip of the collet becomes small due to solder adhesion, etc., so it also prevents the occurrence of scratches on the pellet surface due to solder,
Furthermore, since the same sensor detects pellet adsorption error and collet clogging detection, you will see both the bright and dark signals of the phototransistor at the top of the collet, which is the sensor, and if the detection circuit fails for some reason. In addition, there is an effect that the machine stops due to the mode from which the collet is clogged or the pellet is not adsorbed, and defective products can be prevented from being manufactured.

[Brief description of drawings]

1 is a block diagram of the present invention, FIG. 2 is a schematic view of a collet portion,
Fig. 3 (A), (B), (C shows the timing of the photo interrupter signal for detection timing, the signal of the photo transistor for detection, and the vertical movement timing of the collet when the collet is normal, when the collet is clogged, and when the pellet adsorption error occurs. 1 ... Collet, 2 ... X stage, 3 ... Y stage, 4 ... Z stage, 5 ... Phototransistor, 6
...... Lamp, 7 ...... Pellet suction port, 8 ...... Photo interrupter, 9 ...... Shield plate, 10 ...... Pellet, 11 ......
Lead frame, 12 ... Mount Island, 13 ...
... Collet clogging detection timing signal, 14 ... Pellet adsorption error detection timing signal, 15 ... Photo transistor 5 signal level when collet clogging, 16 ... Photo transistor 5 signal level when pellet adsorption error, 17 ... Photo Signal of interrupter 8, 18 ...
Normal signal of phototransistor 5, 19 ... Vertical timing of collet 1 when normal, 20 ... Signal of phototransistor 5 when collet is clogged, 21 ... Vertical timing of collet 1 when collet is clogged, 22 ... Signal of phototransistor 5 at the time of pellet adsorption error, 23 ...
... timing of collet 1 up and down when pellet adsorption error.

Claims (1)

[Scope of utility model registration request] 1. A lamp which is fixed so as to be positioned between a pellet and a lead frame on which the pellet is mounted and which emits light, and a second stage which is mounted on the first stage and moves up and down. A collet having a light-receiving element and a pellet suction port and fixed to the second stage, the collet moving between the semiconductor pellet and the lead frame with the movement of the first stage, and the first stage. And a shield plate fixed to the collet, which is shielded by the shield plate when the collet moves to adsorb the semiconductor pellets and passes over the lamp to generate a first timing signal. After carrying out the pellet adsorption operation, the intercepted semiconductor pellets are moved to mount and again pass over the lamp. A sensor for generating a second timing signal that is shielded by a plate, and is responsive to the first timing signal to determine whether the light receiving element receives light from the lamp through the pellet suction port of the collet. Of the semiconductor pellet by detecting whether the light receiving element receives light from the lamp through the pellet suction port in response to the second timing signal. A semiconductor element mounting device characterized by detecting a suction error.