JPH0414932Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a semiconductor chip marking device for identifying defective chips, which is used in a semiconductor chip inspection device.

<Prior art> A large number of integrated circuit elements formed on a semiconductor wafer are inspected for electrical characteristics of each element by a semiconductor chip inspection device called a proping machine, and then In a later process, the chip is divided into elements, and only good chips are packaged as semiconductor devices and provided as products. Therefore, the above-mentioned defective chips are removed in the post-process, but in order to remove only the defective chips from a large number of similar circuit elements, it is necessary to attach an identification mark to the defective chips. It is more accurate and very convenient in terms of automation to have the identification mark read by a sorting device.
Therefore, a so-called semiconductor chip marking device has conventionally been provided as a means for attaching the above-mentioned identification mark.

Semiconductor chip marking devices include a scratch type, which creates marks on defective chips on wafers, a laser type, which burns out by irradiating laser light, and an ink type, which attaches ink. . FIG. 2 shows an outline of the configuration of the ink-type marking device. In the figure, a cylindrical movable iron core 2 is inserted into the axial center of the casing 1.
is provided with a return spring 4 so as to be able to advance and retreat a required amount in the axial direction by turning on and off the power to the electromagnetic coil 3 provided in the casing 1 surrounding the iron core. There is. That is, when the power is turned on, it moves forward against the return spring 4, and when the power is turned off, the spring 4 moves it back to its original position. A marking pin 5 is inserted through the movable iron core 2, and the tip of the pin has a length that protrudes from the casing 1 and faces an ink tank to be described later, and the rear side serves as a threaded shaft 5a for the cylinder of the movable iron core 2. It is screwed into a female thread 2a formed on the inner surface. Reference numeral 6 denotes a flange-shaped pin head for position adjustment provided at the upper end of the marking pin 5, and a spring 7 is interposed between the pin head and the movable iron core 2. The tip side of the marking pin 5 is used to guide ink, which will be described later, to the defective chip surface, so in terms of material, in addition to a steel pin with the required rigidity, a plastic pin such as a nylon cord can be used. Ru. 8 is an ink tank;
The marking pin 5 is attached to the bottom of the casing 1.
It is arranged with the tip side facing inside. Reference numeral 9 indicates ink filled in the ink tank 8, and a color that is easy to read by a sorting device in a subsequent process is used. The ink tank 8 has the marking pin 5 facing inside, and the bottom of the ink tank 8 is sealed by capillary action, surface tension, etc. of the ink so that the required time pin can adhere to ink and protrude from the lower end (bottom) of the tank. It has a small diameter nozzle shape that stops.

A marking device configured as described above is attached to a semiconductor wafer inspection device and placed above the semiconductor wafer W, and defective devices (chips) are detected by device circuit inspection.
When marking is performed, when the electromagnetic coil 3 of the marking device is energized by automatic control, the movable iron core 2 advances downward against the return spring 4 due to electromagnetic induction, that is, the tip of the marking pin 5 moves away from the ink tank 8. The ink protruding and led out to the tip of the pin is made to adhere to the corresponding chip surface. Since the above-mentioned energization is carried out instantaneously, after the energization is turned off, the movable iron core 2 is returned to its original position by the elastic force of the return spring 4, that is, the marking pin 5 is moved back.

In this way, in order for the tip of the marking pin 5 to accurately mark the chip surface, positioning the marking pin 5 when it advances is important. This positioning adjustment is performed using the marking pin 5 because the amount of movement of the movable iron core 2 is determined at the time of assembly for each device.
The relative position of the movable iron core is determined using the screw shaft 5a.

In the scratch-type marking device, the ink tank component of the above-mentioned ink-type device is eliminated, and the marking pin 5 is made of, for example, a steel pin that has enough hardness and rigidity to stamp on the chip surface. The device stamps scratches, etc. on the chip surface, and other operating functions are similar to the ink type.

<Problems to be Solved by the Invention> As described above, in the conventional marking devices of the scratch type and the ink type, the positioning of the marking pin has a significant effect on the marking function.

However, as mentioned above, positioning is done by adjusting the marking pin with a screw, so although it is easy to adjust the pin tip due to wear, the screw may become misaligned due to the frequent movement of the movable iron core due to electromagnetic operation. In many cases, the pin rotates back little by little, which may eventually lead to a situation where marking cannot be performed. Therefore, in order to prevent this as much as possible, the movable iron core 2 and the marking pin 5 are connected by a spring 7 that not only absorbs the loosening of the screw but also applies a relative pressing force to the screw part, as shown in FIG. Methods such as repulsion and engagement fixation, or methods such as tightening with a so-called double nut, were used, but in the end, during long-term automatic operation, the pin gradually loosened and the pin gradually retreated. This caused problems in terms of practicality.

<Means for Solving the Problems> In order to solve the problems as described above, the present invention is an electromagnetic device in which a cylindrical movable iron core is provided in a casing, and a marking pin is screwed onto the marking pin so that its axial position can be freely adjusted. Insert the coil and turn on the power to the electromagnetic coil.
In a wafer marking device that is equipped with a return spring and is arranged to move forward and backward, the marking pin advances forward and returns to its original position when the energization is turned off. A sleeve through which the pin head is inserted is formed on the core, and a friction ring is interposed between the insertion portion of the pin head and the sleeve to press against both through elastic deformation.

<Function> There is a friction ring between the pin head of the marking pin and the sleeve of the movable iron core through which the pin head is inserted, which presses against both through elastic deformation, so the elastic force is applied to the circumference of the pin head and sleeve. In other words, the rotational and axial displacement forces of the threaded shaft of the screwed marking pin are absorbed by the frictional resistance all around the circumference, and the shock and vibration caused by the movement of the movable iron core are absorbed by the elasticity mentioned above. Therefore, it is possible to prevent the marking pin from being screwed off due to the above-mentioned impact or the like.

<Example> A preferred example of the present invention will be described below with reference to FIG.

The figure shows an ink-type wafer marking device, in which 10 is a cylindrical casing with a bottom, and an electromagnetic coil 11 is disposed near the bottom of the inner periphery. Reference numeral 11a denotes an electromagnetic coil holder, which is held from the outside of the casing 10 with a screw 11b. The casing 10 includes a holder H having a U-shaped cross section.
It is held together with screw _H1 . The holder H has openings Ha and Hb in the upper and lower holder arm parts, respectively, the casing 10 faces the upper opening side, and the ink tank T is attached to the lower opening side.
Reference numeral 12 denotes a cylindrical movable iron core, which is inserted through the electromagnetic coil 11 and is disposed so as to be freely movable forward and backward. Therefore, when moving forward and backward, when the electromagnetic coil 11 is energized, it moves forward so as to be attracted to the coil side,
A return spring 13 is interposed between the casing 10 and the movable iron core 12 so that the movable iron core 12 returns to its original position when the power supply is cut off. The upper end of the movable iron core 12 forms a sleeve 12a having an inner diameter opening large enough to allow a pin head of a marking pin (described later) to be freely inserted therethrough. Further, the return position of the movable iron core 12 is regulated by a cylindrical stopper bolt 14 screwed into the upper opening Ha of the holder H. In order to prevent vibrations even if the movable iron core 12 collides with the bottom of the casing 10 and the regulating end surface of the stopper bolt 14 in both forward and backward positions during operation, elastic buffer rings ( O-ring) 15 is arranged. This buffer ring may be provided either on the movable iron core 12 side or on the opposing sides of both members.

Reference numeral 16 denotes a marking pin, which has a screw shaft 16a on its proximal end side which is inserted through the movable iron core 12 and screwed into a female thread 12b partially formed in the insertion portion of the iron core, and further has a screw shaft 16a on the base end side. The movable iron core 12 has a pin head 16b having an outer diameter that is inserted into the opening of the sleeve 12a. pin head 1
The end face of 6b is formed with a tool hole, groove, etc. so that it can be rotated from the outside with a tool such as a hexagonal wrench or a driver. The other end of the marking pin 16 faces the ink tank T as a thin line 16c of a required length, so that ink can be deposited on the wafer during the forward and backward marking operation described later.
As the material of the thin wire 16c, the same material as conventional ones can be used.

17 is the pin head 16 of the marking pin 16
This is a friction ring interposed between the pin head 16b and the insertion portion of the sleeve 12a of the movable iron core 12.As shown in the figure, a ring groove is formed in the pin head 16b and the ring is fitted into the groove, or a groove on the sleeve 12a side is fitted. It is mated to The friction ring 17 is made of a rubbery and elastic material, such as a so-called O-ring material, and has a large coefficient of friction against both the pin head 16b and the sleeve 12a. Thus, the intervening state is compressed and deformed due to elasticity and positioned between the intervening states.

The ink tank T has a conventionally known configuration, and is filled with marking ink MI, and the tip of the tank is formed as a tank nozzle TN so that the thin line 16c of the marking pin 16 can lead out the ink MI. .

The marking device with the above configuration is
It is fixed to the mounting bracket of the required semiconductor wafer inspection equipment using the holder H. For marking on the wafer, the electromagnetic coil 11 is turned on and off by a required control signal as in the conventional method, and the ink MI is deposited on the wafer. Therefore, the advancing position of the marking pin 16 has been adjusted in advance by operating the pin head 16b.

If the marking operation is performed according to the above,
The movable iron core 12 is turned on and off by turning the electromagnetic coil 11 on and off.
When the marking pin 16 repeatedly advances and retreats, vibrations occurring particularly at both the advancing and retreating positions are transmitted to the marking pin 16. The vibration is caused by the marking pin 16 and the movable iron core 1.
2, and the turning force due to the threaded inclined surface is applied to the marking pin 16, but since the friction ring 17 is interposed between the pin head 16b and the sleeve 12a of the movable iron core, The force acting on the displacement in the axial direction and the axial rotation direction is the friction ring 17
This is absorbed by the elasticity and frictional resistance of the marking pin 16, thereby preventing the marking pin 16 from shifting due to vibration. That is, since the friction ring 17 is in contact with the pin head and the sleeve at its periphery due to compression deformation, the shearing effect is uniformly received and absorbed over the entire circumference. Also,
If the buffer rings 15 are arranged at both forward and backward positions of the movable iron core 12, the shock vibrations especially at the time of returning and retreating can be absorbed by the buffer rings as well, making it even more effective.

If the thin wire 16c of the marking pin 16 becomes worn due to use, the pin head 16b can be operated with the necessary tool as described above, and the friction ring 17 slides on both the pin head and the sleeve to allow rotation. become.

Although the above embodiment describes an ink-type wafer marking device, the present invention is not limited to this and can also be used in a scratch-type marking device, as explained in the prior art example. Further, in the above embodiment, the casing 10 and the stopper bolt 14 are separated using the holder H, but if the stopper bolt is screwed into the casing, the structure of the above embodiment is not necessarily required. If so, the ink tank T may be attached to the casing 10. However, according to the configuration of the embodiment, the holder H can be used as a mounting jig for the inspection device, and it is also convenient for maintenance such as repair and replacement.

<Effects of the invention> As described above in detail, according to the invention, although it has an extremely simple configuration, it can exhibit excellent practical effects when used continuously for a long time. In addition, since the structure is such that both the movable iron core is formed into a cylindrical shape so that the pin head of the marking pin can be inserted through it, and a friction ring is interposed in that part, there is no disadvantage in terms of cost. It will not affect you.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view showing the configuration of a semiconductor wafer marking device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing an example of the general configuration of a conventional device. 10... Casing, 11... Electromagnetic coil, 1
2...Movable iron core, 12a...Sleeve, 13...
Return spring, 14...Stopper bolt, 15
... Buffer ring, 16 ... Marking pin, 16
a...Screw shaft, 16b...Pin head, 16c...
...Thin wire, 17...Friction ring, H...Holder, T
...Ink tank, MI...Marking ink.

Claims (1)

[Scope of utility model registration request] A cylindrical movable iron core, in which a marking pin is screwed together so that its axial position can be freely adjusted, passes through an electromagnetic coil provided in the casing, and the electromagnetic coil is energized.
In a semiconductor chip marking device that is equipped with a return spring and is arranged to move forward and backward so that the iron core advances when turned on and retreats to its original position when turned off, the pin head for position adjustment operation is formed at the base end of the marking pin shaft. A semiconductor chip marking device characterized in that a sleeve through which the pin head is inserted is formed in the movable iron core, and a friction ring is interposed between the insertion portion of the pin head and the sleeve to be pressed against both by elastic deformation. .