JP5183183B2 - Static eliminator - Google Patents

Description

  The present invention relates to a static eliminator that removes static electricity from, for example, a charged semiconductor wafer or glass substrate, or neutralizes a clean room.

  Semiconductor wafers and glass substrates are prone to static electricity due to contact with rollers during transportation, and fine dust or the like tends to adhere to the surface due to static electricity. For this reason, although the static elimination bar has been used conventionally, sparks are generated and the product yield is reduced. In view of this, Patent Documents 1 to 5 propose to remove charges by bringing a charged fine water droplet into contact with a charged object.

  Patent Document 1 describes that ionized water droplets having a size of 0.5 to 50 μm are generated by adjusting the vibration frequency of the vibrator, and the minute water droplets are used for static elimination of a charged substance. Yes.

  In Patent Document 2, high-purity water is supplied to a two-fluid nozzle and ejected together with pressurized air or pressurized nitrogen to form charged fine water droplets. These fine water droplets are brought into contact with a charged substance to eliminate static electricity. It is described to do.

  Japanese Patent Application Laid-Open No. 2003-228561 discloses a content in which a minute water droplet is charged by disposing an annular dielectric electrode at the tip of a two-fluid nozzle and passing the minute water droplet through the annular dielectric electrode.

  Patent Document 4 discloses the contents of performing the generation and charging of the micro mist simultaneously using the ultrasonic atomization phenomenon and discharging the obtained micro mist to the charged body.

Patent Document 5 describes that a charged micro mist having an average particle diameter of 1 to 10 μm is generated using a two-fluid nozzle. In particular, it is described that when the spray particle size is very small such as 1 to 10 μm, the charged body is not wetted when the charge of the charged body is removed.
JP-A-8-78136 Japanese Patent Laid-Open No. 10-149893 JP 2001-332398 A JP 2005-71899 A JP 2005-78980 A

  In the case of performing static elimination with charged fine water droplets, there is a possibility that water droplets contributing to static elimination may adhere to the static elimination object and wet the surface of the static elimination object.

  According to Patent Document 5, it is described that if the spray particle size is very small (1 to 10 μm), the charged body is not wetted, but it is difficult to always make the spray particles having the above particle size. In addition, when forming a film or a circuit on the surface of a glass substrate for liquid crystal or a semiconductor wafer, it is not preferable that some water droplets remain, and it is not reliable to rely only on the size of the water droplets. .

  In order to solve the above-described problems, the static eliminator according to the present invention performs static elimination by ejecting fine water droplets having a charge from a part of the nozzle that ejects toward a charged object or in the vicinity of the nozzle. A suction means for sucking water droplets was provided.

  The water droplets are not limited to pure water, and may be added with a solvent that easily volatilizes.

  The fine water droplets may be ejected and sucked through the same pipe. Further, the nozzle may be a slit nozzle in addition to a normal nozzle. As an arrangement example, it is conceivable that the nozzle and suction means are set as a set and disposed above and below the static elimination object.

  Further, the nozzle may be movable. As the movement pattern, reciprocation within a certain range can be considered. By setting it as such a pattern, it can prevent that a water droplet concentrates and is supplied to one place.

According to the static eliminator according to the present invention, there is no possibility of generating sparks as compared with the conventional static eliminator bar, and fine water droplets after static elimination do not remain on the surface of the static elimination object. There is no need to add it as a process.

  Embodiments for carrying out the present invention will be described below with reference to the drawings. 1 is a plan view of a glass substrate transfer line to which the static eliminator according to the present invention is applied, FIG. 2 is a side view of the transfer line, FIG. 3 is an enlarged view of the static eliminator, and FIG. 4 is an arrow AA in FIG. FIG. 5 is an enlarged sectional view of a nozzle constituting the static eliminator.

  The glass substrate transport line supports a plurality of shafts 2 in a direction orthogonal to the transport direction between the frames 1 and 1 so as to be rotatable at equal intervals. A pulley 3 is provided at one end of these shafts 2 via a chain or gear (not shown). Thus, the plurality of shafts 2... Rotate in synchronization.

  Each shaft 2 is provided with a roller 4 that contacts the lower surface of the glass substrate W and conveys the glass substrate W.

  By adjusting the length of the predetermined axis 2 among the plurality of axes 2..., A blank area 5 that does not have an axis that is oblique to the transport direction in plan view is provided, and an air knife 6 is provided in the blank area 5 portion. It is arranged to remove water droplets remaining on the back surface of the glass substrate W during cleaning. Note that water droplets remaining on the surface of the glass substrate W can be removed by an air knife (not shown) provided above the glass substrate W.

  And the static elimination apparatus 7 of this invention is arrange | positioned between the shafts 2 and 2 in the downstream of the said air knife 6. FIG. The static eliminator 7 is configured by arranging nozzles 8 having slit-like openings whose longitudinal direction is a direction orthogonal to the transport direction above and below the glass substrate W.

  In the present embodiment, the slit-shaped opening is divided into two by the separation plate 9, and one side is used as a jet port 10 for fine water droplets m charged, and the other is used as a suction port 11 for water droplets m after static elimination. It is said.

  Incidentally, an ultrasonic vibration device that generates water droplets having a particle diameter of 10 μm or less and an electrode for charging fine water droplets generated by the ultrasonic vibration device are disposed on the upstream side of the ejection port 10.

  Moreover, as shown in FIG. 6, you may arrange | position the ejection opening 10 of the water drop m, and the suction opening 11 of the water drop m separately. However, in this case, the distance between the ejection port 10 and the suction port 11 is set to a distance at which water droplets can be sucked. Further, it is desirable to arrange the ejection port 10 on the upstream side and the suction port 11 on the downstream side with respect to the conveyance direction of the glass substrate W.

  FIG. 7 is a plan view of a cool plate to which the static eliminator according to the present invention is applied, and FIG. 8 is an enlarged sectional view of a suction hole portion of the cool plate. In this embodiment, a suction and jet nozzle is formed on the surface of the cool plate 20. 21 is opened at a predetermined interval.

  The suction and ejection nozzle 21 is connected to a vacuum pump and a supply source of charged fine water droplets, and these are switched by a valve. That is, when a glass substrate is sucked, it is connected to a vacuum pump, and when it is neutralized, it is connected to a supply source of water droplets, and fine charged water droplets are sprayed from the suction and jet nozzle 21 toward the lower surface of the glass substrate. Yes.

  However, at the time of the above-mentioned static elimination, all the suction and ejection nozzles 21 do not eject the charged fine water droplets, but the water droplets are ejected from one of the adjacent nozzles 21, and the other nozzle is connected to a vacuum pump to complete the neutralization. Soaked water droplets.

The top view of the glass substrate conveyance line which applied the static elimination apparatus which concerns on this invention Side view of the transfer line Enlarged view of the static eliminator AA arrow view of FIG. Enlarged cross-sectional view of the nozzle constituting the static elimination device The same figure as FIG. 5 which shows another Example of a static elimination apparatus. The top view of the cool plate to which the static elimination apparatus which concerns on this invention is applied Enlarged sectional view of the suction hole part of the cool plate

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Frame of conveyance line, 2 ... Shaft, 3 ... Pulley, 4 ... Roller, 5 ... Blank area, 6 ... Air knife, 7 ... Static elimination device, 8 ... Nozzle, 9 ... Separation plate, 10 ... Fine charged water droplet , 11 ... Water droplet suction port after static elimination, 20 ... Cool plate, 21 ... Suction and jet nozzle, m ... Water droplet, W ... Glass substrate.

Claims (2)

In a static eliminator that discharges charged fine water droplets from a nozzle toward a charged object and makes contact with the object to remove static electricity, this static eliminator ejects fine charged water droplets and performs static elimination. A plurality of suction and ejection nozzles for sucking water droplets, these suction and ejection nozzles being connected to a vacuum pump and a source of charged fine water droplets, and the suction and ejection nozzles are adjacent to one suction and ejection nozzle by a valve. A neutralizing device characterized in that the ejection nozzle is connected to a vacuum pump, and the other adjacent suction and ejection nozzle is connected to a source of charged fine water droplets . 2. The static eliminator according to claim 1, wherein the suction and ejection nozzle is provided on a cool plate .

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