JP2715756B2 - Substrate cleaning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate cleaning apparatus,
In particular, the present invention relates to an apparatus for cleaning an insulating substrate having a thin film transistor such as an active element for a liquid crystal display formed on a surface in a completed or semi-finished state.

[0002]

2. Description of the Related Art In a manufacturing process of an active matrix substrate for a liquid crystal display, it is necessary to perform a brush cleaning in order to remove adhered particles of about 10 μm and residues after a dry etching process.

FIG. 3 is a sectional view showing a conventional cleaning apparatus of this kind. The substrate 3 is transported by a transport roller 1 driven by a shaft 2. A brush 6 for cleaning the substrate 3 is supported by a bearing member 9 and is directly connected to a rotating shaft 7 driven by a motor 11. Bearing member 9
A bearing 10 is provided in the inside for smooth rotation of the rotating shaft 7.
The screw is carved so that it can move up and down. The table 8 is moved up and down by the feed screw 4. At this time, the amount of movement of the brush 6 in the direction of the substrate 3 is detected by the dial gauge 6 fixed to the apparatus wall 13.

Prior to cleaning, the contact point between the brush and the substrate is adjusted by raising and lowering the bearing member 9 for each brush.
That is, the position of the bearing member 9 is adjusted so that the brush 6 comes into contact with the substrate with zero contact pressure. Next, the feed screw 4 is turned, and the table 8 is lowered to a point where a predetermined pushing amount is obtained. Here, the pushing amount refers to the distance that the brush descends from the zero contact point. In this state, the surface active agent is supplied to the surface of the substrate 3 and the brush 6 is rotated by the motor 11 to perform cleaning.

[0005]

In the conventional cleaning apparatus described above, adjustment of the zero point of contact between the brush and the substrate depends on the sense of the individual. For this reason, there are problems such as individual differences in the adjustment position of the contact zero point, and the contact zero point of each brush does not match. As a result, there is a problem that a uniform cleaning effect cannot be obtained between and within the substrates, and a product of uniform quality cannot be obtained.

[0006] In the stage of mass production, the substrates may move irregularly, such as overlapping or riding on conveying rollers. However, in the conventional example, there is a problem that the substrate cracks in such a case. Also happened.

[0007]

In order to solve the above-mentioned problems, in the substrate cleaning apparatus according to the present invention, a torque limiter is provided between each brush rotating shaft and the motor.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention. The substrate 3 is transported by a transport roller 1 driven by a shaft 2. A brush 6 for cleaning the substrate 3 is directly connected to a rotating shaft 7 and is rotated by a motor 11. A torque limiter 12 is provided between the motor 11 and the rotating shaft 7, so that the torque of the torque limiter does not apply a predetermined torque to the substrate 3.

All brushes are supported via a bearing member 9 on a table 8 which is moved up and down by a feed screw 4.
The brush position with respect to the table 8 is adjusted by the bearing member 9. The amount by which the brush 6 is pushed into the substrate 3 is detected by the dial gauge 5.

Using the cleaning apparatus of this embodiment, cleaning was performed in the following manner. Substrate: 400mm (substrate flow direction) x 300mm Inverted stagger type TFT substrate (no passivation film) Brush: 3 pieces with a diameter of 60φ, made of 0.2φ nylon Brush position: perpendicular to the substrate flow direction, from the edge of the substrate 7
5mm, 150mm, 225mm arranged in a row Brush rotation speed: 200rpm Detergent: Surfactant (NCW-601; manufactured by Wako Pure Chemical Industries) Substrate transfer speed: 0.3m / min Zero adjustment: limit the torque limiter with a brush Is set to the lowest point that can rotate without load. The bearing member 9 is lowered and fixed at the point where the limiter starts operating. Push-in amount: 2.0 mm Torque limiter set value: Set to operate with a load five times that of the load during normal washing (push-in amount 2.0 mm)

After brush cleaning, the product is washed with pure water of 18.1 MΩ · cm, drained with an air knife, and then washed with an air knife.
Oven drying was performed at ℃. After this operation, a passivation film was applied, and the TFT substrate was assembled into a module.

At 50 ° C. for the assembled module
While aging, were measured V _G ^OFF. here,
The V _G ^OFF, and that the gate voltage when where the TFT serving as the TFT and the off-state which is turned mixed, in the applied state of the voltage, the display unevenness on the panel is observed. FIG. 2 shows the measurement results. As shown in FIG. 2, in the cleaning area by the present embodiment (area ~), through aging time, V _G ^OFF range is small. That is, according to the present embodiment, uniform substrate cleaning is performed in the plane, and as a result, the degree of deterioration of the TFT off characteristic is uniformed in the plane.

[0013]

As described above, according to the present invention, the torque limiter is installed between the brush and the drive motor.
The effect is obtained that the zero point disagreement for each brush can be solved at once. As a result, uniform cleaning effect across substrate and the substrate is obtained, it is possible in the operation of the color LCD module, to suppress the variation due to aging V _G ^OFF characteristics.

Further, even if the substrate moves irregularly such as riding on the transport roller during cleaning, there is also a secondary effect that the substrate can be suppressed from cracking because the torque limiter works.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a graph showing the effect of the embodiment of FIG.

FIG. 3 is a sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveyance roller 2 Shaft 3 Substrate 4 Feed screw 5 Dial gauge 6 Brush 7 Rotating shaft 8 Table 9 Bearing member 10 Bearing 11 Motor 12 Torque limiter 13 Device wall

Claims (1)

(57) [Claims] An apparatus for cleaning a substrate having a thin film transistor formed on a surface thereof in a completed or semi-finished state, comprising: a rotating brush in contact with a substrate surface; a driving shaft directly connected to the rotating brush; A substrate cleaning apparatus comprising: a mechanism for moving the brush vertically; a motor for rotating the rotary brush; and a torque limiter disposed between the motor and the drive shaft.