JP2889449B2 - Cleaning equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for removing dust adhering to a protective film called a pellicle film formed on a reticle used in an exposure process in a process of manufacturing a semiconductor device or a liquid crystal display device.

[0002]

2. Description of the Related Art FIG. 10 shows a reticle 1 on which a pellicle film 2 is formed. FIG. 10A is a sectional view of the reticle 1, and FIG. 10B is a plan view thereof. The reticle 1 is a so-called mask in which a wiring pattern 4 is formed on a glass substrate using a light-shielding material, for example, chromium. On both surfaces of the reticle 1, a thickness of several tens μm
A pellicle film 2 made of, for example, nitrocellulose is arranged. The pellicle film 2 is disposed so as to cover the entire surface on which the wiring pattern 4 is formed, that is, over the hatched portion shown in FIG. Further, the pellicle film 2 is arranged at a distance of about several mm from the reticle 1 by the metal frame 3. By providing the pellicle film 2 as described above, dust is prevented from directly adhering to the surface of the reticle 1 on which the wiring pattern 4 is formed, and the wiring pattern generated by the transfer of the dust as a wiring pattern during exposure is provided. Can be reduced.

FIG. 11 is a diagram for explaining the role of the pellicle film 2 during exposure. FIG. 11A shows a case where the pellicle film 2 is not used, and FIG. 11B shows a case where the pellicle film 2 is used. As shown in FIG. 11A, when dust 5 adheres to the surface of the reticle 1 on which the wiring pattern 4 is formed, when exposure is performed using the lens 6, the image forming point S due to the dust 5 is It is formed on the lens-side surface 7a of the substrate 7 formed by transfer. For this reason, the wiring pattern is short-circuited by the dust 5 and the substrate 7 becomes defective, thereby reducing the productivity of the semiconductor device and the liquid crystal display device.

On the other hand, when a pellicle film 2 is used as shown in FIG.
The dust 5 adheres to the pellicle film 2 over the entire surface on which the wiring pattern 4 is formed. When exposure is performed in such a state, an image forming point S due to dust 5 is formed at a point beyond the substrate 7. For this reason, the bad influence by the dust 5 can be reduced, and the productivity can be improved.

However, depending on the size of the dust 5 adhering to the pellicle film 2, even if the pellicle film 2 is provided, the wiring pattern 4 may be short-circuited. Generally, there is no effect when the thickness is several tens to several hundreds μm, but a short circuit occurs when it is several hundreds μm or more. Therefore, dust having a size of several hundred μm or more needs to be removed.

The removal of dust having a size of several hundred μm or more is performed by using an air gun 8 as shown in FIG. From the air gun 8, for example, nitrogen (N ₂ ) gas from which dust has been removed by a filter is injected. An operator takes out the reticle 1 on which the pellicle film 2 is formed from the inside of the exposure apparatus, and blows a dust (N ₂ ) gas to a portion where dust is adhered or an entire pellicle film 2 with an air gun 8 to remove the dust. All of these operations are performed manually.

[0007]

As described above, all dust removal operations are performed manually, and the exposure process is temporarily interrupted, which is troublesome and reduces the work efficiency. The problem arises. Moreover, since the pellicle film 2 is formed by hand, the very thin pellicle film 2 may be damaged by the air gun 8 or the hand. When the pellicle film 2 is damaged, it can be replaced when it is damaged, but there is a problem that it takes time and cost. Furthermore, since the removal is performed by taking out the inside of the exposure apparatus having a high degree of cleaning, there arises a problem that floating dust adheres at the time of entering and exiting, and the removed dust adheres again.

[0008] An object of the present invention is to provide a cleaning apparatus capable of efficiently removing deposits on the surface without damaging the protective film.

[0009]

According to the present invention, there is provided a housing having an opening formed on one side wall, and a wiring pattern formed of a light-shielding material on a surface of a substrate made of a light-transmitting material. Conveying means for loading and unloading the reticle having a protective film formed at an interval from the surface into and out of the housing from the opening, and angularly displacing the reticle carried by the conveying means between a vertical state and a horizontal state. And a gas flow jetting means for jetting a gas flow onto a surface of the reticle held in the vertical state.

[0010] Further, the cleaning apparatus of the present invention is characterized in that the cleaning apparatus further comprises an exhaust means provided in the housing for exhausting the gas injected from the gas flow injection means.

[0011]

According to the present invention, a reticle on which a protective film called a pellicle film is formed is carried in from the opening formed in the housing by the carrying means, and is held horizontally by the holding means. The reticle held horizontally is
The vertical position is held by the angular displacement of the holding means, and a gas flow is jetted from the gas flow jetting means to the surface of the reticle, and the deposits attached to the protective film surface of the reticle are blown off and removed. When the injection of the gas flow is completed, the holding means for holding the reticle is angularly displaced, and the reticle is held in a horizontal state again. The reticle held in the horizontal state is carried out of the housing by the carrying means. Therefore, the removal of the deposit is mechanically and efficiently performed, and the breakage of the very thin protective film can be reduced, and the cost and time required for replacing the protective film can be reduced.

Further, since the injected gas is exhausted by the exhaust means, the removed deposits are also sucked and discharged to the outside of the housing, so that re-adhesion to the protective film can be prevented.

Further, by integrating the cleaning apparatus with the exposure apparatus, it is possible to remove deposits without taking out the reticle from the exposure apparatus having a high degree of cleaning, and it is possible to further reduce the adhesion of dust.

[0014]

FIG. 1 shows a cleaning apparatus 11 according to one embodiment of the present invention.
FIG. 2 is a side view of the cleaning device 11, and FIG. 2 is a plan view of the cleaning device 11. The cleaning device 11 is configured to be covered by a housing 12. Housing 12
A transfer port 12a, which is an opening, is formed on the inner surface of the housing 12. An air shower 14 described later and nitrogen (N ₂ ) injected from the air shower 14 are formed on an inner surface 12b of the housing 12.
An exhaust port 13 for exhausting gas is formed. further,
Inside the housing 12, holding means for holding the reticle 51 and performing angular displacement is formed.

The holding means includes a stage 15 having a plurality of stoppers 16 and 17 provided to prevent a reticle 51 described later from falling. Stage 15
Is fixed to the shaft 18, and the rotation of the shaft 25 is transmitted to the shaft 18 by a driving mechanism described later, and the stage 15 is angularly displaced. The shafts 18 and 25 are rotatably inserted into the insertion holes 19 a of the frame 19. Two stages 15 are provided as shown in FIG. 2 to securely support the reticle 51. The cleaning device 11 having such a configuration is formed integrally with an exposure device 31 described later.

FIG. 3 is a plan view showing a schematic configuration of the exposure apparatus 31, and FIG. 4 is a side view thereof. Exposure device 31
A work storage unit 34 including a work cassette 32 for storing a work, that is, a substrate on which a wiring pattern is transferred and formed, and a transfer arm 33 for transferring the work, an XY stage 35, dust detection Device 37, reticle case 38, cleaning device 11 described above, reticle 5
1, a transfer arm 21, a projection lens 39,
And exhaust means 40.

The exhaust means 40 of the exposure apparatus 31 is provided with, for example, a HEPA (High Efficiency Particle Air) filter, and the inside of the apparatus 31 is kept at an optimum cleanliness. The work stored in the work cassette 32 is set on the XY stage 35. The installation of the work is performed by the transfer arm 33. XY
The stage 35 is moved in the direction X by motors 36X and 36Y.
And the direction Y can be moved in two directions, and fine adjustment is performed by this adjustment.

Above the XY stage 35, the above-described cleaning device 11, dust detection device 37, reticle case 38, projection lens 39, and transfer arm 21 for transferring the reticle 51 are arranged. . Dust detector 37
Is a means for detecting whether dust adheres to the pellicle film 52 formed on the reticle 51 by, for example, a light scattering method. The reticle case 38 holds the reticle 5
1 is a case for storing the same. The projection lens 39 is
This is a lens used when transferring the wiring pattern formed on the reticle 51 onto the work set on the XY stage 35. Focusing is performed by moving this lens 39 in the vertical direction. Transfer the wiring pattern. Reticle case 38, dust detection device 37,
And the reticle 51 in and out of the cleaning device 11,
The transport between these apparatuses and the transport on the exposure path are performed by scanning the transport path T with the transport arm 21.

As shown in FIG. 2, the transfer arm 21 has two elongated rod-shaped tips 22. In addition, a projection 23 is formed at the tip of the tip 22. The reticle 51 is set on such a transfer arm 21 and transferred. Since the two tip portions 22 of the transfer arm 21 are formed with a space therebetween, the reticle 51
The pellicle film 52 formed on the substrate is not damaged, and the exposure process can be performed without any problem. Also,
The removal of the reticle 51 held on the stage 15 can be performed without any problem by pulling out the reticle 51 by the projection 23.

FIG. 5 is a perspective view showing the stoppers 16 and 17 for holding the reticle 51 on the stage 15 provided in the above-described cleaning apparatus 11. FIG. 5A shows the stopper 16 formed on the stage 15, and FIG. 5B shows the stopper 17. The reticle 51 carried into the cleaning device 11 by the transfer arm 21 is
And one stage 16 of the stopper 16 and one surface 17 of the stopper 17
a contacts one side surface 51 a of the reticle 51. Therefore, the reticle 51 is prevented from dropping from the stage 15 due to vertical and horizontal vibrations.
Further, the other side surface 51 b of the reticle 51 is in contact with the other surface 16 b of the stopper 16. Therefore, the stopper 16
The reticle 51 does not slide down even when the stage 15 is tilted with the other surface 16b of the other side down, and is held by the stage 15.

FIG. 6 is a perspective view schematically showing an angular displacement mechanism of the stage 15. As shown in FIG. The shaft 18 is fixed to the stage 15, and the shaft 25 is connected to the motor 20. Shaft 18, 2
5 is rotatably inserted into the insertion hole 19 a of the frame 19. The rotational force of the shaft 25 generated by driving the motor 20 is transmitted to the shaft 18 by the belt 24 and angularly displaces the stage 15 fixed to the shaft 18 between a horizontal state and a vertical state. Further, a sensor 26 for controlling the rotation of the shaft 25 is formed on the shaft 25. When the shaft 25 is angularly displaced by an angle required for the stage 15 to be angularly displaced in a horizontal state or a vertical state, the angular displacement becomes Set to stop. This angular displacement mechanism is moved up and down by a lifting means (not shown).

FIG. 7 is a perspective view showing the structure of the air shower 14. As shown in FIG. FIG. 7A is a perspective view showing one surface 27 a of the housing 27 covering the entire air shower 14, and FIG. 7B is a perspective view showing the other surface 27 b of the housing 27. The housing 27 has a plurality of insertion holes 28.
Are formed, and tubes 29 each having a diameter of about 5 mm are inserted into the insertion holes 28, respectively. A gas which is pressurized to an appropriate pressure and from which dust is removed, for example, a nitrogen (N ₂ ) gas is injected from the pipe 29.

FIG. 8 is a view showing the reticle 51 on which the pellicle film 52 is formed. FIG. 8A is a cross-sectional view of the reticle 51, and FIG. 8B is a plan view thereof. The reticle 51 is a so-called mask in which a wiring pattern 54 is formed on a glass substrate using, for example, chrome as a light-shielding material. On both surfaces of the reticle 51, pellicle films 52 having a thickness of several tens of μm and made of, for example, nitrocellulose are arranged. The pellicle film 52 is disposed so as to cover the entire surface of the wiring pattern 54, that is, over the entire hatched portion shown in FIG. Further, the pellicle film 52 is several m from the reticle 51 by the metal frame 53.
They are arranged at intervals of about m. By providing the pellicle film 52 in this manner, dust is prevented from directly adhering to the surface of the reticle 51 on which the wiring pattern 54 is formed, and a short circuit of the wiring pattern caused by transfer of dust during exposure is reduced. can do.

FIG. 9 is a side view for explaining the cleaning process of the cleaning device 11 step by step. When the dust detection device 37 determines that dust is attached, the cleaning device 1
In step 1, the attached dust is removed. As shown in FIG. 9A, the reticle 51 installed on the transfer arm 21 is carried in from the transfer port 12 a of the cleaning device 11 and is held on the stage 15. When the reticle 51 is completely held on the stage 15, the transfer arm 21 goes out of the cleaning device 11. Next, the motor 20 is driven to angularly displace the stage 15 in the direction A shown in FIG.

Stage 15 holding reticle 51
Means that nitrogen (N ₂ ) gas ejected from the air shower 14 together with the frame 19 is supplied to the pellicle film 5 on the reticle 51.
2, for example, in the direction B shown in FIG. Next, nitrogen (N
₂ ) The gas is blown out for 10 seconds, for example, and the reticle 51
The dust attached to the upper pellicle film 52 is blown off. At this time, the pellicle films 52 formed on both surfaces of the reticle 51 may be processed simultaneously by the plurality of air showers 14, or may be processed one by one. The removed dust is exhausted from the exhaust port 13 together with nitrogen (N ₂ ) gas. Therefore, the removed dust is prevented from re-adhering to the pellicle film 52. This exhaust may be started at the same time as the operation of the air shower 14 or may be started after the air shower 14 stops. The evacuation time is, for example, 10 seconds or 12 seconds. When the dust removal is completed in this way, the stage 15 is moved together with the frame 19 as shown in FIG.
It rises in the direction C shown in (4).

Subsequently, the motor 15 is driven to angularly displace the stage 15 by approximately 90 ° in the direction D shown in FIG. The reticle 51 from which dust has been removed is carried out of the cleaning device 11 by the transfer arm 21.
The unloaded reticle 51 is, for example, a dust detection device 37.
It is determined whether or not dust is attached to the sheet. When dust is attached, the above-described cleaning process is repeated, and when dust is not attached, the next process, for example, an exposure process is performed.

As described above, according to this embodiment, the cleaning device 11 is provided with the air shower 14 and the exhaust port 13.
The reticle 51 on which the pellicle film 52 has been formed
The stage 1 is carried into the housing 12 from the stage 2a.
5 and is subjected to a cleaning process. Further, the cleaning device 11
Are integrated with the exposure device 31. Therefore, dust can be removed mechanically and without damaging the pellicle film 52. Further, the pellicle films 52 disposed on both surfaces of the reticle 51 are simultaneously processed by the plurality of air showers 14 provided inside the housing 12, so that dust can be efficiently removed.

Further, the removed dust is discharged from the exhaust port 13 and the cleaning device 11 is integrated with the exposure device 31 having a high degree of cleaning. Waste dust does not adhere again.

[0029]

As described above, according to the present invention, the reticle on which the protective film is formed is carried into the housing from the opening of the housing by the carrying means, and is held by the holding means. A gas flow is jetted from the gas jetting means to the held reticle to remove the deposits attached to the protective film. Therefore, it is possible to mechanically and efficiently remove the attached matter, and to reduce damage to the protective film.

Further, according to the present invention, the removed deposits are discharged to the outside of the housing by the exhaust means, so that reattachment to the protective film can be prevented, and efficient and reliable removal can be achieved. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a side view in which a side surface of a cleaning apparatus 11 according to an embodiment of the present invention is cut off.

FIG. 2 is a plan view in which an upper surface of the cleaning device 11 is cut away.

FIG. 3 is a plan view showing a schematic configuration of an exposure apparatus 31.

FIG. 4 is a side view showing a schematic configuration of the exposure apparatus 31.

FIG. 5 is a perspective view showing stoppers 16 and 17 for holding the reticle 51 on the stage 15.

FIG. 6 is a perspective view schematically showing an angular displacement mechanism of a stage 15;

FIG. 7 is a perspective view showing the air shower 14;

FIG. 8 is a view showing a reticle 51 on which a pellicle film 52 is formed.

FIG. 9 is a side view for explaining a cleaning process of the cleaning device 11 step by step.

FIG. 10 is a view showing a reticle 1 on which a pellicle film 2 is formed.

FIG. 11 is a diagram for explaining the role of the pellicle film 2 during exposure.

FIG. 12 is a cross-sectional view illustrating a conventional cleaning method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cleaning device 12 Housing 12a Transport port 13 Exhaust port 14 Air shower 15 Stage 21 Transport arm 51 Reticle 52 Pellicle film

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/027 B08B 5/00 G03F 1/08

Claims (2)

(57) [Claims] 1. A housing having an opening formed on one side wall surface, a wiring pattern formed of a light-shielding material on a surface of a substrate made of a light-transmitting material, and a light-transmitting protective film spaced from the surface. Transport means for loading and unloading the reticle into and out of the housing from the opening; holding means for angularly holding the reticle loaded by the transport means between a vertical state and a horizontal state; and A gas flow jetting means for jetting a gas flow to a surface of the reticle held in a vertical state. 2. The cleaning apparatus according to claim 1, further comprising an exhaust unit provided in the housing and configured to exhaust the gas injected from the gas flow injection unit.