JP2000189907A - Oscillation mechanism and washing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly oscillate an oscillation arm with good accuracy by providing the above mechanism with an oscillation shaft mounted with an oscillation arm, a rotational drive source disposed with an output shaft in parallel to the oscillation shaft adjacently to the oscillation shaft and a link mechanism for transmitting the rotation of the output shaft to the oscillation arm. SOLUTION: When a step motor is driven by rotating a washing member 12, a motor shaft 26 oscillates and the oscillation thereof is transmitted via the link mechanism 30 and the oscillation shaft 16 to the oscillation arm 14, causing the washing member 12 to oscillate so as cross a semiconductor substrate in an approximately diametral direction to wash the substrate. The oscillation of the motor shaft 26 is transmitted via the link mechanism 30 to the oscillation shaft 16 in the washing apparatus. These shafts 16 and 26 and the drive link member 31 and the driven link member 34 or the link members 32 and 34 and a connecting link member 36 are so constituted as not to give rise to shaking therebetween and, therefore, the washing member 12 may be smoothly oscillated along the surface of the substrate with the good accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oscillating mechanism suitable for use in a cleaning apparatus for cleaning a substrate requiring a high degree of cleanliness, such as a semiconductor substrate, a glass substrate, and a liquid crystal panel.

[0002]

2. Description of the Related Art In recent years, as the degree of integration of semiconductor devices has increased, the wiring of circuits on a semiconductor substrate has become finer, and the distance between the wirings has become smaller. Accordingly, when a circuit is formed by optical lithography or the like, the depth of focus becomes shallow, so that a higher flatness of the imaging surface of the stepper is required. As means for flattening the surface of a semiconductor wafer, FIG.
And a polishing cloth (polishing cloth) 5 on the upper surface as shown in FIG.
0, and a chemical / mechanical polishing apparatus (CMP) P including a polishing table 52 to which the semiconductor wafer W is held and pressed against the polishing table 52 while holding the semiconductor wafer W. Used. For this, a nozzle 58 for supplying the polishing liquid Q to the polishing cloth 50 is provided above the polishing table.
Dressing device 6 for regenerating (dressing) polishing cloth
0 is attached.

FIG. 8 shows a CMP unit constituted as a unit including such a CMP apparatus P and its auxiliary equipment. The CMP apparatus P is provided at one end of a substantially rectangular floor, and the polishing apparatus is provided at the other end. Load and unload units 64a and 64 for accommodating cassettes accommodating semiconductor wafers to be accommodated
b are provided between the transfer robots 66a and 66.
b is provided so as to be able to run. Transfer robot 66a,
On both sides of the traveling path 66b, reversing machines 68a and 68b for reversing wafers and cleaning machines 70a and 7 for cleaning are provided.
0b and 70c are provided.

By the way, in a process such as polishing of a semiconductor substrate, particles such as fine particles, dust, and crystal projections of a semiconductor piece may adhere thereto. If particles larger than the distance between the wirings exist on the semiconductor substrate, problems such as short-circuiting of the wirings occur. Therefore, the particles existing on the substrate must be sufficiently smaller than the distance between the wirings. Such a situation is the same in the process of processing a glass substrate used as a mask or the like or a substrate such as a liquid crystal panel. With such demands, a cleaning technique for dropping finer submicron-level particles from a semiconductor substrate or the like is required.

FIG. 4 shows the structure of a cleaning machine 70b shown in FIG. 8, which holds a semiconductor substrate W to be cleaned by a spin chuck (clamp) 10 and rotates the semiconductor substrate W horizontally at a predetermined speed. The cleaning member 12 is slid on the surface to be cleaned of the substrate W to scrub the surface to be cleaned. The cleaning member 12 is attached to the tip of a swing arm 14 supported by a swing shaft 16 and can swing over the surface to be cleaned of the substrate W, and rotates by a driving mechanism built in the swing arm 14. It is possible.

Since a predetermined moment acts on the oscillating arm 14 and the oscillating shaft 16 supporting the oscillating arm 14 by a reaction force from the substrate W, the oscillating arm 14 itself has sufficient rigidity, and the oscillating shaft 16 has a sufficient strength. It is supported by a bearing structure having a high rigidity. A driving source such as a motor is provided adjacent to the swing shaft, and transmits power via a transmission mechanism having a gear, a timing belt, and the like provided between the two.

FIGS. 5 and 6 show an example in which a gear is used. A fan-shaped driven gear 22 is fixed to a swing shaft 16 rotatably supported on a bracket 20 via a bearing 18, and a step motor is provided. A drive gear 28 meshing with the driven gear 22 is fixed to an output shaft (motor shaft) 26 of the motor 24. As a result, the forward / reverse rotation of the step motor 24 at a predetermined rotation angle is transmitted to the swing shaft 16 via the gears 22 and 28, and the swing arm 14 swings within a predetermined range.

[0008]

However, backlash is essentially inevitable in a gear as a power transmission means. In particular, at the time of reversal where the forward and reverse rotations are reversed, a deviation occurs between the rotation of the motor shaft and the rotation of the swing shaft, and it has been difficult to smoothly swing the swing arm.
As a result, there is a problem that it is not possible to strictly control the movement trajectory of the cleaning member, or it is difficult to perform uniform cleaning over the entire surface of the object to be cleaned. Such a problem similarly occurs when a timing belt is used as the power transmission means due to belt extension or the like.

As means for reducing the backlash, the distance between the motor shaft and the oscillating shaft can be adjusted so that the distance between the motor shaft and the oscillating shaft can be adjusted according to the variation in the size of the gears. ,
It is known that a double gear is used to absorb backlash by its phase difference, but in each case, not only is the structure complicated, but also adjustment work is required during assembly. It is cumbersome and not practical.

The present invention has been made in view of the above circumstances, and has as its object to provide a swing mechanism that can swing a swing arm accurately and smoothly with a relatively simple structure.

[0011]

According to a first aspect of the present invention, there is provided a swing shaft having a swing arm attached thereto, and an output shaft provided adjacent to the swing shaft in parallel with the swing shaft. And a link mechanism for transmitting the rotation of the output shaft to the swing arm.

With this structure, the rotation of the output shaft of the rotary drive source can be transmitted to the swing shaft accurately with a relatively simple structure.
The swing arm can be smoothly and accurately swung.

According to a second aspect of the present invention, there is provided a cleaning apparatus including the swing mechanism according to the first aspect, wherein a cleaning member is attached to a tip of the swing arm.

According to a third aspect of the present invention, there is provided a dressing apparatus comprising the swing mechanism according to the first aspect, wherein a dressing tool is attached to a tip of the swing arm.

According to a fourth aspect of the present invention, there is provided a polishing apparatus comprising the swing mechanism according to the first aspect.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a first embodiment of the present invention in which the swing mechanism of the present invention is applied to the cleaning apparatus shown in FIG. 4, and FIG. The same members as in the example will be described with the same reference numerals.

In this cleaning apparatus, a semiconductor substrate W to be cleaned is held by a spin chuck (clamp) 10 and horizontally rotated at a predetermined speed. A cleaning member 12 for scrub-cleaning the surface to be cleaned and a cleaning liquid nozzle provided at a predetermined location are provided. The cleaning member 12 is attached to the tip of a swing arm 14 supported by a swing shaft 16 and can swing over the surface to be cleaned of the substrate W, and rotates by a driving mechanism built in the swing arm 14. It is possible.

The oscillating arm 14 and the oscillating shaft 16 supporting the oscillating arm 14 are formed with sufficient rigidity by themselves, and the oscillating shaft 16 includes a bearing 18 and a bracket 20 having sufficient rigidity. It is rotatably supported by the bearing structure. Further, although not shown,
The oscillating shaft 16 is moved up and down, and the cleaning member 12 is moved to the substrate W.
An elevating / lowering / pressing device such as an air cylinder for pressing with a predetermined pressure is provided thereon.

Adjacent to the oscillating shaft 16, a step motor 24 whose rotation angle can be easily controlled is connected to the motor shaft 2.
6 are provided in parallel with each other, and a link mechanism 30 is provided between the oscillating shaft 16 and the motor shaft 26 to rotate the two in synchronization. This link mechanism 30
Drive link member 3 having its base end fixed to motor shaft 26
2, a driven link member 34 having a base end fixed to the swing shaft 16, and a connecting link member rotatably connected to the free ends of the link members 32 and 34 to form a parallel link structure therewith. 36.

The drive link member 32 and the motor shaft 26
The driven link member 34 and the oscillating shaft 16 have a width that allows the motor shaft 26 and the oscillating shaft 16 to pass through mounting holes formed in the link members 32 and 34, respectively, and to be fitted into key grooves formed therein. It is fixed without play by inserting the key. Further, the drive link member 32, the driven link member 34, and the connection link member 36
Is connected without any play by inserting a pin 38 having a size that fits into a pin hole provided at the end of each of the link members 32 and 34. In addition, you may make it support a pin via a bush, a bearing, etc. In addition, as long as a play-free state can be achieved without using a key or a pin, a friction joint (trade name: positive lock) may be used.

Next, the operation of this embodiment will be described. The semiconductor substrate W to be cleaned is transferred onto the cleaning device by an arm of a robot or the like, and is held by the spin chuck 10 (see FIG. 4) with the surface to be cleaned facing upward. And
The substrate W is rotated at a predetermined number of revolutions, and at the same time, the cleaning liquid is supplied from the cleaning liquid nozzle toward the substantially center of the substrate W as needed. The lifting / lowering / pressing device of the oscillating shaft 16 is operated to press the cleaning member 12 against the substrate W surface at a predetermined pressure.

In this state, when the cleaning member 12 is rotated and the stepping motor 24 as a driving source is driven, the motor shaft 26 swings within a predetermined angle range, and the swing is caused by the link mechanism 30 and the swing shaft. Swing arm 1 through 16
The cleaning member 12 is oscillated so as to cross the semiconductor substrate W in a substantially diametrical direction and scrub-cleans the surface to be cleaned.

In this cleaning device, the swing of the motor shaft 26 is transmitted to the swing shaft 16 via the link mechanism 30, and these shafts 16, 26, the drive link member 32 and the driven link member 34, or these Is not so loose between the link members 32 and 34 and the connecting link member 36 that there is no problem of backlash as in a gear mechanism or belt elongation as in a belt mechanism. Can be smoothly and accurately swung along the surface of the substrate W.

When the substrate W is dried after the scrub cleaning operation is completed, the liquid supply from the nozzle is stopped, the swing shaft 16 is raised, and the spin chuck 10 is rotated at high speed to perform spin drying. When the next cleaning step is performed, the substrate W is transported to the next step so as not to dry the surface to be cleaned.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, a cleaning liquid nozzle 40 capable of jetting a cleaning liquid at a predetermined pressure is used as a cleaning member. In this embodiment, the cleaning liquid is jetted from the tip of the cleaning liquid nozzle 40 toward the substrate while the rocking arm 14 is oscillated, and the substrate W is cleaned with the injection pressure. Other configurations are the same as in the first embodiment.

Although the example in which the swing mechanism of the present invention is applied to a washing machine has been described above, the application of the present invention is not limited to this. For example, in the polishing apparatus P shown in FIGS. 7 and 8, the swing mechanism of the present invention can be used for the swing arm 54 of the top ring 56. In the polishing apparatus P, the semiconductor wafer W is held on the lower surface of the top ring 56, and the swing arm 54 is swung while pressing the semiconductor wafer W against the polishing cloth 50 on the upper surface of the polishing table 52 by the lifting cylinder. At the same time, the polishing liquid Q is supplied from the polishing liquid nozzle 58. Thereby, the top ring 56 swings smoothly on the polishing table surface, and the polishing is stably performed.

A swing arm 72 of a dressing device 60 for dressing the polishing cloth 50.
Alternatively, the swing mechanism of the present invention may be used. The dressing device swings smoothly on the cloth 50 surface of the polishing table 52 to perform dressing.
4.

[0028]

As described above, according to the present invention,
With a relatively simple structure, the rotation of the output shaft of the rotary drive source can be accurately transmitted to the swing shaft, and the swing arm can be smoothly and accurately swung. Alternatively, by applying the present invention to a dressing device for a tool, it is possible to achieve excellent effects such as improvement of each function and controllability and reduction of equipment and operation costs.

[Brief description of the drawings]

FIG. 1 is a plan view showing a main part of a cleaning apparatus according to a first embodiment of the present invention.

FIG. 2 is a front view showing a part of FIG.

FIG. 3 is a partially cutaway front view showing a cleaning apparatus according to a second embodiment of the present invention.

FIG. 4 is a perspective view of a cleaning device.

FIG. 5 is a front view showing a part of a conventional cleaning device in a cutaway manner.

FIG. 6 is a sectional view taken along the line AA of FIG. 5;

FIG. 7 is a view showing a polishing apparatus according to a third embodiment of the present invention.

FIG. 8 is a plan view showing the overall configuration of the polishing unit.

[Explanation of symbols]

 12, 40 Cleaning member 14 Oscillating arm 16 Oscillating shaft 24 Step motor (rotary drive source) 26 Motor shaft (output shaft) 30 Link mechanism 32 Drive link member 34 Driven link member 36 Connection link member

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Kenichi Shigeta 72 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Kawasaki Plant (72) Inventor Takeshi Watanabe 72-72 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Company F Toshiba Kawasaki Office F-term (reference) 3B116 AA02 AA03 AB34 AB42 BA02 BA08 BA13 BA34 BB22 BB45 BB62 CC03 3C058 AA07 AA09 AA11 AA19 AC01 AC05 DA17

Claims (4)

[Claims] 1. A swing shaft to which a swing arm is attached; a rotation drive source provided adjacent to the swing shaft with an output shaft parallel to the swing shaft; A swing mechanism for transmitting the swing mechanism to the swing arm. 2. A cleaning apparatus comprising the swing mechanism according to claim 1, wherein a washing member is attached to a tip of the swing arm. 3. A dressing apparatus comprising the swing mechanism according to claim 1, wherein a dressing tool is attached to a tip of the swing arm. 4. A polishing apparatus comprising the swing mechanism according to claim 1.