JPH0368768A - Rotational taking up device for coating fine wire - Google Patents

Abstract

PURPOSE:To form the uniform film of an inorg. material on the surface of a fine wire by installing the rotational taking up device for coating a fine wire to the vacuum chamber of a vacuum device and making a vapor deposition operation simultaneously with delivery of the fine wire while rotating the wire around its axial direction. CONSTITUTION:This rotating device for coating the fine wire is installed to the vacuum chamber 36 of a dry coating device, such as sputtering, ion plating, vacuum vapor deposition of plasma CVD. The delivery and taking up of the coiled fine wire 4 are executed and simultaneously the fine wire 4 is rotated around the progressing direction thereof as an axis 12. The material to be evaporated is thereby deposited by evaporation uniformly on the fine wire.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is directed to coating the surfaces of various thin wires with a uniform film, and in particular coating the surfaces of thin wires for bonding semiconductor chips and external leads with a dry coating method. The present invention relates to a coating rotary winding device used to continuously and uniformly coat an inorganic substance.

(Prior art) Thin wires, such as bonding thin wires that connect semiconductor chips and lead frames, were used bare, but in recent years, bonding has become increasingly dense, and as a result, contact between the thin wires occurs and circuits are damaged. It is becoming increasingly common for chips to short-circuit and interfere with the normal functioning of the chip.

Therefore, a method of coating the surface of the bonding thin wire with an insulating film made of organic polymer resin has been proposed, for example, in JP-A-58-23.
As disclosed in Japanese Patent No. 39, the resin film as described above may remain on the surface of the thin wire (on the bonding ball) when the chip and the thin wire are bonded, resulting in poor bonding. Therefore, Japanese Patent Application Laid-Open No. 63-318132 discloses that this residual resin is blown away with gas and removed by suction.
This has the problem of complicating the equipment.

On the other hand, it has been considered to coat the surface of the thin wire with an inorganic substance instead of an organic resin by a dry coating method such as sputtering, ion blasting, vacuum deposition, or plasma CVD.

In general, dry coating methods such as sputtering, ion blasting, vacuum evaporation, or plasma CVD can cover a wider range of materials than coating methods such as wet plating or coating with polymers dissolved in a solvent. It is widely used mainly in the semiconductor industry as a method for producing functional thin films because it has the advantage of being flexible and easy to control the film thickness.

However, in the general dry coating method, the material that is deposited to form a thin film flies in almost one direction from a deposition source such as a crucible in a vacuum chamber or a (sputtering) target, and is deposited on the substrate. Although this is good when coating a substrate with a flat or similar shape, when coating the surface of a three-dimensional substrate, the vapor deposition material does not wrap around to the shadowed part when viewed from the vapor deposition source. Therefore, it was difficult to coat the film uniformly.

In particular, when coating a thin wire-shaped substrate that is much longer than a vacuum chamber, it is necessary to perform coating while sending the thin wire wound on a peg-like reel to the deposition zone. As a result, it was impossible to obtain a uniform film thickness because the proportion of the vapor deposited in the shaded area when viewed from the source was reduced.

As a solution to this problem, a method such as so-called hollow cathode sputtering uses a device with an axially symmetrical structure and sends out the thin wire into a space corresponding to the axis, thereby uniformly coating any part of the surface of the thin wire. It has been devised for a long time.

However, this method requires a specialized device with a complex configuration including a cylindrical arrangement of the target and gas introduction part, and it is difficult to control the deposition conditions because it is not possible to arrange a counter electrode in addition to the thin wire. There were drawbacks.

(Problems to be Solved by the Invention) The present invention enables uniform inorganic material to be coated on the surface of a fine wire by using a dry coating method carried out on a boat, without using a specially shaped vapor deposition device in which the deposition conditions are difficult to control as described above. The object of the present invention is to provide an apparatus for forming a film.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following points. In other words, a thin wire sending reel is rotatably attached to a support base having a flange, and a fine wire sending reel is connected to the flange to rotate a rotating body for rotating the support base. A take-up reel is installed, and a thin wire winding mechanism is arranged to rotate coaxially, and a thin wire winding mechanism is provided, in which a rotating body for rotating the support base is connected to the flange, and a rotating body is connected to the interlocking device. A rotary winding device for thin wire coating, characterized in that a synchronous rotation mechanism rotated by external power is connected to the respective rotating bodies of the sending mechanism and the winding mechanism so as to interlock with each other.

It is also a feature of the present invention that the following conditions can be added to the invention as summarized above.

That is, the above invention is characterized in that: 1. Each support of the feeding mechanism and the winding mechanism is provided with a thin wire guide spool; 2. The feeding mechanism support is provided with a plurality of spools capable of controlling the tension as well as the thin wire guide. .

The device of the present invention is installed in a vacuum chamber of a dry coating device for sputtering, ion blasting, vacuum evaporation, or plasma CVD, and simultaneously sends out and winds up a thin wire wound into a coil, and simultaneously moves the thin wire in its traveling direction. By rotating it around the axis, it is possible to uniformly deposit the evaporated substance.

Compared to wet plating methods or coating methods using polymers dissolved in a solvent, dry coating methods generally allow for a wider range of materials to be formed into the film, and are easier to control the film thickness. It has its features.

As a coating method, the sputtering method coats a dense thin film with particularly good controllability of film thickness, and the ion blasting method has the characteristic of being able to coat a thin film with high adhesion in a short time.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a front view of the present invention, and FIG. 2 is a plan view thereof. In the figure, A is the thin wire feeding mechanism, and B is the thin wire I!
The winding mechanism C indicates a synchronous rotation mechanism.

The thin wire delivery mechanism A is configured as follows. That is, on an L-shaped support 1 having a flange 1', a delivery reel 3 rotatably attached to a support shaft 2 is fixed via the support shaft 2, and is provided in parallel in the delivery direction of the fine wire 4. A spool 8°9.10 rotatably attached to each of the support shafts 5, 6°7 is connected to the support shaft 5.6. It is fixed via 7. Further, a rotary gear 11 for rotating the support base 1 is connected to the flange 1' via a shaft 12. 1
Reference numeral 3 denotes a frame that supports the rotating shaft 12 via a bearing 20.

Above spool 8. 9.10 can be installed as needed, but in this example, three are provided (support ID
15.6. 7 or spool 8. 9.10 shall be of removable construction. ). This plays the role of guiding the thin wire so that the direction of movement of the thin wire coincides with the central axis of rotation when feeding out the thin wire, and also adjusting the tension during winding to move the thin wire so that it does not sag. For this reason, it is preferable to have a structure in which, for example, the shaft 6 is movable in a direction orthogonal to the rotation axis of the support base, and the weight depth between the front and rear spools can be controlled.

The fine wire winding mechanism B is provided with an L-shaped support base 14 having a flange 14' like the feeding mechanism A, and the support base 14 has a bearing 15 fixed to the base 14 to support the winding-lumi 6. It supports the rotating shaft 17 with the attached.

A support rotating gear 18 is fixed to the flange 14' via a shaft 19, and the shaft 9 is connected to the frame 13' via a bearing 20.
is supported by 21 is a transmission gear for rotating the reel 1B, and is fixed to one end of a shaft 22 rotatably supported by a bearing 2a.

A bevel gear 23 is fixed to the other end of the shaft 22, and the gear 23 is connected to the take-up reel rotation shaft via an intermediate transmission gear 25 supported by a bearing 24 fixed on the support base 14. It is connected to a reel rotation gear 26 attached to 17. Reference numeral 27 denotes a fine wire guide spool rotatably engaged with the support shaft 28, which is attached as necessary to guide the fine wire so that it moves along the center axis of rotation. In addition, the support shaft 28 is removable,
fixed to a support.

The synchronous rotation mechanism C has the following configuration. That is, synchronous rotating gears 30 and 31 are fixedly installed on both ends of the rotating shaft 29, and a driving gear 32 is fixedly connected to the driving motor M. Reference numeral 33 denotes a feed-out side synchronous interlocking gear connected to the support rotating gear of the fine wire sending mechanism A, and 34 denotes a winding side synchronous interlocking gear connected to the support rotating gear 18 of the fine wire winding mechanism B.

An interlocking gear 35 that is connected to the rotation transmission gear 21 of the take-up reel is fixed to the take-up side synchronous interlocking gear 34 .

In the above configuration, the thin wire 4 wound around the feed reel 3 is wound around the take-up reel 16 with the direction of rotation as the axis of rotation.
It is wound up. That is, the synchronous rotating shaft 29 driven by the motor M synchronously rotates the gears 30, 31 on both sides, and transmits this power to the support rotating gears 11, 18 through the interlocking gears 33, 34. The rotating gear 11.18 is connected to the shaft 12.
The supports 1 and 14 are rotated synchronously in the same direction around and 19. Similarly, the power from the interlocking gear 35 is transmitted to the transmission gear 2.
This rotation is transmitted to the reel rotation gear 26 from the bevel gear 23 and the intermediate transmission gear 25, and the rotation is transmitted to the reel rotation gear 26.
Rotate 6. The thin wire 4 is rotated and pulled by the rotation of the take-up reel 1B, and is fed out from the freely rotating feed-out reel 3 and wound onto the take-up reel 16. At this time, the thin wire is transferred to each flange of the support base. The reel 3.16 is arranged so as to coincide with the center (i.e., the rotation axis) of the support shaft 12.19 of the reels 1' and 14'. This can be achieved regardless of the arrangement of the reel 3616 by arranging the spools 1O and 27, which are erected on each support stand, so that the thin wire is located at the central axis of rotation.

3 and 4 show another embodiment of the present invention, in which the thin wire 1 is configured to reciprocate between the feeding mechanism A and the winding mechanism one or more times.

That is, the support shafts 7 and 28 are fixed to the support stand 1 on the feeding mechanism side and the support stand i4 on the winding mechanism side, and guide spools 10° 10' and 27.27' are attached to the support shafts 7 and 28, respectively. It is rotatably mounted. The fine wire 4 fed out from the feed reel is guided by the spool 1O and transferred to the spool 27, which is then turned and transferred to the spool 1.
0', and is further guided to the spool 27' and wound onto the reel 1B. In this way, the thin wire 4 is connected to the spool 10.
27, and at this time, the thin wire moves while rotating near the central axes of the mechanisms A and B, which are rotated by shafts 12 and 19. In this embodiment, two spools are supported on each support stand, but by increasing the number of spools, the number of reciprocations of the thin wire can be increased. Incidentally, the other structure of this embodiment is the first one.
The configuration is similar to that shown in FIG.

In the above embodiments, the rotation transmission mechanism was explained as having a configuration using gears, but the present invention is not limited to this.
It goes without saying that the object can also be achieved by employing another means capable of synchronous rotation, such as a chain three belt system.

The apparatus of the present invention is installed in a vacuum chamber of a dry coating apparatus. FIG. 5 shows an example in which the present invention is installed in an ion blating apparatus. That is, 36 in the figure is a vacuum chamber, 3
7 is an exhaust pipe that communicates with the vacuum pump and reduces the pressure inside the tank; 88
39 is an atmospheric gas supply pipe, and 39 is a device of the present invention, which is fixed to a pedestal 4o attached to the tank wall. 41 is a crucible into which the evaporated substance is inserted, 42 is an electron beam (EB) gun, and 43 is a high-frequency induction coil that transports the evaporated substance in the direction of the arrow. Thin line 1
is arranged to advance through the deposition zone 44 in a direction perpendicular to the flow direction (arrow) of the deposition material.

Application examples of the present invention are shown below.

A thin gold alloy bonding wire with a diameter of 30H and a length of 20m was set in the rotating winding device shown in Figure 1, placed in the vacuum chamber of the ion blating device, and the surface was coated with aluminum oxide for insulation coating. did. The coating conditions were as follows.

Method: Ion blasting Evaporated substance: Al
□O1 powder atmosphere: Ar and O2 mixed (1:1) gas introduction, 5 x 10-'Torr Evaporation method: EB, 10kV, 20
0mARF Ha'7-: 0.1klll Coil feed speed: 27cm/i1n.

Film thickness: 25OA Thin wire temperature: room temperature When the composition of the thin film formed on the bonding thin wire after coating was analyzed by AES method, it was found to have the same composition as the Habo target. Also, CMA the cross section of the thin wire.
A surface analysis (X-ray analysis) revealed that aluminum oxide was coated uniformly along the sides of the thin wire.

(Effects of the Invention) The thin wire coating rotary winding device of the present invention is installed in a vacuum chamber of a vacuum device, and the thin wire is fed out while rotating around the wire direction as an axis, and at the same time vapor deposition operation is performed. The thin film can be coated onto thin wires such as thin wires, other metal wires, synthetic fibers, or carbon fibers. In particular, during the vapor deposition process, the thin wire moves in line with the central axis of rotation, so the amount of vapor deposition becomes almost uniform, and a dense and uniform inorganic film can be obtained on the surface of the thin wire.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and the first figure is a front view and the second figure is a front view.
The figure shows a plan view. Fig. 3 is a front view of another embodiment; Fig. 4 is a front view of another embodiment;
The figure is a partial plan view of FIG. 3, and FIG. 5 is a diagram showing an example of use of the present invention. A: Fine wire feeding mechanism B: Fine wire winding mechanism C Double synchronous rotation mechanism 1: Support stand 1': Flange 2: Support shaft
3: Feeding rule 4: Thin a
5.6.7: Support shaft 8.9, 10 varnish spool 11: Support base rotation gear 12: Shaft 13.13': Frame 14': Flange 14: Support base 15: Bearing 1B 2nd take-up reel 17: Take-up reel Rotating shaft 18: Support base rotating gear 19: Axis
20:1Ill receiver 21:Transmission gear 2
2: Shaft 23: Bevel gear 24: Bearing 25: Intermediate transmission gear 26: Reel rotation gear 27: Guide spool 28: Support shaft 29: Synchronous rotation axis ao, 31: Synchronous rotation gear 32: Drive gear 33:
Delivery side synchronous interlocking gear

Claims (5)

[Claims] 1. A thin wire feed-out mechanism includes a fine wire feed-out reel rotatably attached to a support base having a flange, and a rotating body that rotates the support base is connected to the flange; In addition to installing a take-up reel, a thin wire winding mechanism having a rotating body connected to the flange that rotates the support base and a rotating body connected to the interlocking device is arranged so as to rotate coaxially, 1. A rotary winding device for thin wire coating, characterized in that a synchronous rotation mechanism rotated by external power is connected so as to interlock with each rotating body of the sending mechanism and the winding mechanism. 2. 2. The rotary winding device for thin wire coating according to claim 1, wherein each support of the feeding mechanism and the winding mechanism is provided with a thin wire guide spool. 3. 3. The rotary winding device for thin wire coating according to claim 1, wherein a plurality of spools are provided on the feeding mechanism support stand. 4. Claim 1 characterized in that the rotation axis of the thin wire that rotates and advances in the coating area provided between the delivery reel and the take-up reel is set to be coaxial with the rotation axes of the delivery mechanism and the take-up mechanism. , 2 or 3. The rotary winding device for thin wire coating. 5. The thin wire that rotates in the coating area provided between the delivery reel and the take-up reel is at least once
4. The rotary winding device for fine wire coating according to claim 1, wherein the feeding mechanism and the winding mechanism are arranged so as to reciprocate.