JP2839673B2 - Cleaning method and cleaning device for bonding tool - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tape carrier for joining, for example, an inner lead formed on a tape carrier to a semiconductor element as a member to be bonded by pressurizing the inner lead with a heated bonding tool. More particularly, the present invention relates to a cleaning method and apparatus for cleaning a tool surface of a bonding tool.

(Prior Art) A semiconductor manufacturing apparatus, for example, an inner lead bonding apparatus is as shown in FIG.

That is, reference numeral 1 denotes a stage, and a semiconductor element 2 as a member to be bonded is provided on a predetermined portion of the stage 1.
Are positioned and positioned by a positioning mechanism (not shown). Reference numeral 3 denotes a tape carrier, which is intermittently sent so that device holes 4 opening at predetermined intervals are sequentially opposed to the semiconductor elements 2 on the stage 1. Each device hole 4 has an inner lead 5
Is protruding.

A bonding tool 6 is disposed above the stage 1 and can move up and down to abut on the stage 1. A cartridge heater (not shown) is integrally attached to the bonding tool 6, and heats the bonding tool 6 to, for example, 400 to 500 ° C.
The bonding tool 6 is connected to a pressure driving source (not shown) and can press the semiconductor element 2 on the stage 1 with a predetermined pressure.

The heated bonding tool 6 is driven downward by aligning a large number of electrodes 7 of the semiconductor element 2 positioned and held on the stage 1 with the inner leads 5 of the tape carrier 3. The electrodes 7 and the inner leads 5 perform a collective bonding operation.

As described above, the inner lead bonding apparatus is automated, and even if the electrodes 7 of the semiconductor element 2 and the inner leads 5 of the tape carrier 3 have extremely small pitches, collective connection is possible, thereby shortening the bonding processing time and improving reliability. The property can be improved.

(Problems to be Solved by the Invention) By the way, the bonding tool 6 is usually made of an extremely hard material, and does not wear out even if the above-described pressurizing and heating action is repeated for a long time. .
However, since it is heated to a high temperature by the cartridge heater, the oxide easily adheres to the tool surface 6a which is the bonding action surface.

That is, tin plating is applied to the surface of the inner lead 5, and a very small amount of tin is melted by the bonding action and adheres to the tool surface 6a. The attached tin is oxidized and converted into an oxide, deposited with the bonding action, and gradually increases in thickness.

Such oxides adhering and depositing on the tool surface 6a are interposed between the tool surface 6a and a portion to be newly bonded, lowering the heat transfer coefficient of the tool surface 6a itself, and deteriorating bonding reliability.

Therefore, in such an inner lead bonding apparatus, it is necessary to periodically clean the tool surface 6a to remove stains such as oxides.

For example, Japanese Patent Application Laid-Open No. 56-153743 discloses a device provided with a cleaning mechanism for removing a stain such as an oxide by sliding a grindstone that is rotationally driven on a tool surface.

However, particles such as oxides removed from the tool surface may be scattered and floated around the cleaning mechanism and the bonding tool, and may adhere to them again.

Therefore, JP-A-63-166238 and JP-A-63-25
No. 0829 discloses an arrangement in which a nozzle is arranged on one side of a bonding tool and a cleaning mechanism, and a suction duct is arranged on the other side of the bonding tool and the cleaning mechanism.

That is, high pressure air is blown out from the nozzle together with the operation of the cleaning mechanism, and is blown to the bonding tool and the cleaning mechanism. Fine particles such as oxides removed from the tool surface are sucked into the suction duct and do not scatter around.

However, since the bonding tool is always heated to a high temperature so that the bonding action is possible,
In addition to the oxide of tin, for example, tin is attached to the tool surface in a molten state.

Even if a grindstone constituting a cleaning mechanism is slid on such a tool surface, the molten tin is not easily removed because it is spread over the entire slid surface. Then, if the grindstone is separated from the tool surface, the melted tin component is oxidized again with the lapse of time, which may cause the above-described problem.

Furthermore, the whetstone is made of a material softer than the bonding tool so that the whetstone will not be damaged even if it slides on the tool surface. When the tool surface is slid in contact with such a grindstone, the cleaning effect of the tool surface is performed and the abrasive grains constituting the grindstone are peeled off. When the grindstone is separated from the tool surface after the cleaning, the oxide fine particles and the abrasive grains of the grindstone are attached to the tool surface.

In this state, even if air is blown out from one side of the bonding tool and the cleaning mechanism as described in JP-A-63-166238 and JP-A-63-250829 described above, the blowing direction is the bonding tool. In addition, since it is from the side of the cleaning mechanism, there is a problem that it is not possible to completely blow off abrasive particles and fine particles such as oxides adhering to the tool surface.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a bonding tool cleaning method and a cleaning apparatus capable of completely removing a substance adhering to a tool surface of a bonding tool and improving bonding accuracy and reliability.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a tape carrier for joining leads formed on a tape carrier to a member to be bonded by pressing the leads with a bonding tool heated to a bonding temperature. A method of cleaning a bonding tool for removing an adhering substance attached to the bonding tool when manufacturing a semiconductor device of a system, wherein a cooling step of cooling the bonding tool to a temperature lower than a melting temperature of the adhering substance; An adhering matter removing step of removing adhering matter adhering to the tool surface of the bonding tool cooled in the step, and a temperature increase for heating the bonding tool from which the adhering matter has been removed in the adhering matter removing step to raise the temperature to the bonding temperature. And a bonding tool comprising: Cleaning method.

Further, according to the present invention, when manufacturing a tape carrier type semiconductor device in which leads formed on a tape carrier are pressurized by a bonding tool heated to a bonding temperature and bonded to a member to be bonded, the leads adhered to the bonding tool. An apparatus for cleaning a bonding tool that removes extraneous matter, comprising: an adhering matter removing means for polishing the tool surface of the bonding tool to remove the extraneous matter; and a tool disposed opposite to the tool surface of the bonding tool. A spraying means for blowing gas onto the surface to blow off the adhered matter remaining on the tool surface; and a suction means for vacuum-suctioning the periphery of the bonding tool and sucking the adhered matter blown off by the spraying means. Cleaning tool for bonding tools characterized by the following: It is a device.

By adopting the means for solving the above problems, the bonding tool is cooled to a temperature lower than the melting temperature of the adhered substance, and the adhered substance adhered to the tool surface is solidified, and then the adhered substance is removed. , Removal is assured.

Then, the temperature of the bonding tool is again raised to a predetermined bonding temperature after removing the deposits from the tool surface, so that the bonding operation after cleaning is reliably performed. Since the removed deposits are collected and not scattered around, the occurrence of secondary obstacles is prevented.

(Embodiment of the Invention) Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, a cartridge heater 8 is integrally attached to the bonding tool 6 and a thermocouple 9 is attached. The cartridge heater 8 and the thermocouple 9 are electrically connected to a temperature controller 10 to heat the bonding tool 6 to a set temperature and simultaneously perform temperature detection.

The temperature controller 10 is electrically connected to, for example, a control device 11 of an inner lead bonding device, which is a semiconductor manufacturing device, and performs data communication such as a set temperature to the bonding tool 6 from the control device 11 via the temperature controller 10. To be able to

Below the bonding tool 6, there is provided a slide table 14 having a female thread (not shown) which is slidably inserted into the guide rail 12 and is screwed to the ball screw 13.

A drive motor 15 is connected to one end of the ball screw portion 13 so as to be rotatable in the forward and reverse directions. By rotating and driving the ball screw portion 13, the slide table 14 can be moved in any direction. .

The slide table 14 is provided with an air blow unit 16 and a cleaning unit 17, which will be described later.

First, the air blow unit 16 will be described. An air blow hole 19 is opened at a substantially central portion of the upper surface of the unit body 18 facing the tool surface 6a of the bonding tool 6, and surrounds the air blow hole 19. The upper surface opening of the air suction chamber 20 is opened.

The other end of the air blow hole 19 is open to a side surface of the unit body 18 and is connected to a compressed air pipe (not shown). The compressed air pipe is provided with an electromagnetic on-off valve electrically connected to the control device 11 and a compressed air source, and these constitute an injection unit.

A suction hole 21 communicates with the air suction chamber 20, and the other end of the suction hole 21 is open to the side surface of the unit body 18. A vacuum pipe (not shown) is connected to the suction hole 21. The vacuum pipe is provided with an electromagnetic on-off valve electrically connected to the control device 11 and a vacuum source, and these constitute suction means.

Next, the cleaning unit 17 will be described. A housing 22 having a rotating shaft protruding from the upper and lower surfaces is disposed on the slide table 14, and a grinding wheel 24 is fitted to the rotating shaft protruding upward via a disc-shaped grindstone receiving base 23 and a spring (not shown). .

That is, the grindstone 24 faces the tool surface 6a of the bonding tool 6, and is elastically supported by the grindstone cradle 23. A drive motor 25 is disposed on the side of the housing 22. Pulleys 26 and 26 are fitted on the rotation shaft projecting downward and the rotation shaft projecting downward from the housing 22, respectively. A drive belt 27 is stretched between 26 and 26. The drive motor 25 is
They are electrically connected to the control device 11 and constitute a deposit removing means.

Thus, as described above with reference to FIG.
The inner leads 5 of the tape carrier 3 are opposed to the electrodes 7 of the bonding tool 6, and the tool surface 6a of the heated bonding tool 6 is heated.
Are abutted and pressurized to bond the electrodes 7 to the inner leads 5. When such a bonding tool operation is performed a predetermined number of times, it is determined that an oxide or the like has adhered to the tool surface 6a, and the following operation is performed.

During the bonding operation, the bonding tool 6 is controlled to be maintained at a high temperature of about 400 to 500 ° C. by the cartridge heater 8. Here, the cleaning temperature for the tool surface 6a of the bonding tool 6 is set from the control device 11 to the temperature controller 10 by data communication. This temperature is a temperature lower than the metal melting point of the object to be pressed in the bonding tool 6, that is, the melting point of tin plated on the surface of the inner lead 5, for example, 200 to 300 ° C.

The control device 11 outputs a low-temperature instruction signal to the temperature controller 10 to stop the heating operation of the cartridge heater 8, and outputs a drive signal to the drive motor 15 to move the slide table 14. And the above air blow unit
It stops when the upper surface of the 16 unit bodies 18 faces the tool surface 6a of the bonding tool 6.

The compressed air source is communicated with the air blow hole 19,
The vacuum source and the air suction chamber 20 are communicated. The compressed air blown out from the air blow holes 19 is blown onto the tool surface 6a of the bonding tool 6, and a cooling process for cooling the same is performed. Also, through the air blow hole 19, the tool surface 6a
The air that has been blown by the air and the ambient air around the bonding tool 6 and the ambient air around the bonding tool 6 are sucked into the air suction chamber 20.

As a result, the bonding tool 6 rapidly drops to a temperature lower than the metal melting temperature of the deposit, which is the set temperature, and the oxide and the melted tin attached to the tool surface 6a are completely solidified. .

When this temperature is detected by the thermocouple 9 and the control device 11 determines through the temperature controller 10, the air blow and the air suction operation are stopped.

Next, as shown in FIG. 2, the drive motor 15 is driven again to slide the slide table 14, and the grindstone 24 of the cleaning unit 17 is moved to the tool surface 6a of the bonding tool 6.
Stop when facing. Then, the drive motor 25 of the cleaning unit 17 is driven to rotate the grindstone 24 and the bonding tool 6 is lowered, so that the tool surface 6a
Is brought into contact with the grindstone 24.

The solidified oxide and the like adhering to the tool surface 6a are efficiently peeled off. Further, at this time, if the bonding tool 6 and the grindstone 24 are relatively moved in the XY directions, even more effective cleaning can be performed.

After a lapse of a predetermined time, as shown in FIG. 3, the drive motor 25 of the cleaning unit 17 is stopped, and the slide table 14 is moved again, so that the upper surface of the unit body 18 of the air blow unit 16 is brought into contact with the tool surface of the bonding tool 6.
Stop when facing 6a.

Then, the compressed air source and the air blow hole 19 are communicated, and the vacuum source and the air suction chamber 20 are communicated. The compressed air blown out from the air blow holes 19 is blown onto the tool surface 6a of the bonding tool 6, and is separated from the tool surface 6a by the grinding wheel 24, and blows off the adhered material which is still attached to the tool surface 6a.

That is, the deposit is a mixture of fine particles of the oxide and the solidified tin, and abrasive grains separated from the grindstone 24.
The attached matter blown off from the tool surface 6a is sucked by the vacuum action of the surrounding air suction chamber 20, and does not scatter around.

As a result, the tool surface 6a is completely cleaned, and the adhered matter removed therefrom is surely collected, and the adhered matter removing step without any adverse effect on the surroundings is completed.

Next, the control device 11 sends data communication to the temperature controller 10 to cause the cartridge heater 8 to generate heat, set a bonding temperature of 400 to 500 ° C., and shift to a temperature increasing step of heating the bonding tool 6. When the thermocouple 9 detects an increase in the temperature of the bonding tool 6, the bonding operation is restarted.

In the above embodiment, as a semiconductor manufacturing apparatus,
Although the description has been made by applying the inner lead bonding, the present invention is not limited to this, and includes all devices that press and bond a bonding member to a member to be bonded using a heated bonding tool.

In the above embodiment, the slide table 14 is provided below the bonding tool 6, and the air blow unit 16 and the cleaning unit 17 are provided here. For example, the air blow unit 16 and the cleaning unit 17 are fixed. The bonding tool 6 may be slidably positioned.

The number of pre-programmed bondings does not necessarily have to be the same.For example, if the tool surface 6a is cleaned after 100 bonding operations, the tool surface 6a should be cleaned after 99 bondings the next time. Alternatively, the number of times of bonding may be gradually reduced.

Although the grindstone 24 is used as a means for slidingly adhering to the tool surface 6a, a material similar to the grindstone 24 such as a sandpaper or a polishing tape may be used instead.

As a cooling means for solidifying the deposits adhered to the tool surface 6a of the bonding tool 6, a compressed air blowing and a vacuum suction structure are employed. Alternatively, for example, N2 gas or reducing gas is blown. Alternatively, a cooling structure in which a water path is formed in the bonding tool 6 to conduct cooling water may be employed.

(Effect of the Invention) As described above, according to the present invention, the bonding tool is cooled to a temperature lower than the melting temperature of the deposit,
This is a cleaning method that removes extraneous matter adhering to the tool surface of the cooled bonding tool and raises the temperature of the bonding tool from which the extraneous matter has been removed to the bonding temperature again, so that the extraneous matter attached to the tool surface is removed. In addition, the bonding operation after the restart is reliable and the reliability can be improved.

The present invention also provides an adhering substance removing means for removing an adhering substance by polishing the bonding surface of a bonding tool,
Injecting means which is disposed opposite to the bonding surface of the bonding tool and blows gas to the bonding surface to blow off the remaining material on the tool surface, and vacuums the periphery of the bonding tool to suck the blown-off material. Since the cleaning device is provided with the suction means, the cleaning of the tool surface is ensured, and the adhered matter that has been removed is not scattered to the surroundings.

[Brief description of the drawings]

FIGS. 1 to 3 are views showing a bonding tool surface cleaning step in order, showing an embodiment of the present invention, and FIG. 4 is an enlarged view of a bonding state in a semiconductor manufacturing apparatus. 3 Tape carrier, 5 Inner lead, 6 Bonding tool, 2 Bonded tool member (semiconductor element), 6a Tool surface, 16 Air blow unit, 17 Cleaning unit, 24 …… Whetstone,
19 ... air blow hole, 20 ... air suction chamber.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-150853 (JP, A) JP-A-3-64937 (JP, A) JP-A-3-44047 (JP, A) JP-A-63-1988 16956 (JP, A) JP-A-58-28845 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 21/60 311

Claims (2)

(57) [Claims] When manufacturing a tape carrier type semiconductor device in which leads formed on a tape carrier are pressurized by a bonding tool heated to a bonding temperature and bonded to a member to be bonded, the leads adhered to the bonding tool. In a cleaning method of a bonding tool for removing an adhering matter, a cooling step of cooling the bonding tool to a temperature lower than a melting temperature of the adhering matter, and an adhering method attached to a tool surface of the bonding tool cooled in the cooling step. A method for cleaning a bonding tool, comprising: an adhering matter removing step of removing an adhering matter; and a temperature increasing step of heating the bonding tool from which the adhering matter has been removed in the adhering matter removing step to increase the temperature to the bonding temperature. 2. A manufacturing method of a tape carrier type semiconductor device in which leads formed on a tape carrier are pressurized by a bonding tool heated to a bonding temperature and bonded to a member to be bonded. An apparatus for cleaning a bonding tool that removes deposits, comprising: an attachment removal unit that polishes a tool surface of the bonding tool to remove the attached deposits; and a tool that is disposed to face the tool surface of the bonding tool. An injection unit that blows a gas onto a surface to blow off the adhered substance remaining on the tool surface by polishing, and a suction unit that suctions a vacuum around the bonding tool and suctions the attached substance blown off by the injection unit. Cleaning tool for bonding tools characterized by the following: Device.