JP3103997B2 - Tray cleaning equipment in in-line type film forming 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 tray cleaning apparatus used in a mass production type film forming apparatus such as an in-line type plasma CVD apparatus and a sputtering apparatus.

[0002]

2. Description of the Related Art Conventionally, for example, in-line plasma CV
In the D apparatus, a large number of trays as shown in FIG. 1 are prepared, a substrate is mounted on each tray, and sequentially sent to a plurality of film forming chambers of the apparatus to form a film on the substrate. In the illustrated example, the tray a is suspended by a carrier d having wheels c moving along an upper rail b, and a pinion gear f engaged with a rack e provided on the carrier d is driven by a motor (not shown). ), The carrier d moves together with the tray a. The rails b are laid in each of the film forming chambers arranged in the in-line type, and a loading chamber and an unloading chamber provided before and after the film forming chambers. A pinion gear f is also provided in each of these chambers for moving the carrier d. A substrate g is attached to the tray a by an appropriate means, and a thin film is formed on the surface of the substrate g.

[0003] Since the tray a mounts the substrate g and enters the film forming chamber, a thin film adheres to the surface of the tray a. Since there is an inconvenience of deteriorating the film quality, it is necessary to periodically clean and remove it. Conventionally, for this removal, the tray a is removed from the carrier d and moved to another place, where the unnecessary thin film on the tray a is removed by glass bead blasting (glass particle spraying method), liquid honing or pickling. After the removal, the work of attaching the tray a to the carrier d was performed again.

[0004]

According to the method for removing a thin film described above, a thick film can be removed relatively easily, but mechanical pressure is applied to the surface of the tray a in glass bead blasting or liquid honing. Therefore, the tray a is easily deformed, and the SiO ₂ and SiNx films can be removed by pickling.
There is a disadvantage that Si and poly-Si films cannot be easily removed. In particular, in the case of a large-sized plasma CVD apparatus, the position of the substrate is not accurately determined due to the deformation of the tray, and the film thickness distribution of the film formed on the substrate changes largely due to the deformation. It was necessary to give due consideration to the situation. Further, since the tray of the large-sized plasma CVD apparatus is generally formed of a thin plate or a frame, the tray may be deformed when it is removed from the carrier and moved. Therefore, it is desired that a force in the direction perpendicular to the surface of the tray is not applied in a series of tray cleaning steps.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tray cleaning apparatus for an in-line type film forming apparatus which can perform cleaning without applying a force for deforming the surface of the tray and has good workability.

[0006]

According to the present invention, in an in-line type film forming apparatus for forming a film on a substrate by sequentially moving a tray on which the substrate is mounted in a plurality of film forming chambers, the substrate on which the film is formed is formed. A cleaning unit that accommodates the detached tray, a movable unit that accommodates the entire tray that accommodates the tray, and a cleaning chamber that includes a vacuum exhaust unit, an etching gas introduction unit, and a plasma generation unit or a tray and a carrier heating unit. By doing so, the above object is achieved.

[0007]

When the thin film accompanying the film formation on the substrate adheres to the tray to the extent that it has to be removed, the tray from which the substrate has been removed is transferred together with the carrier to a movable trolley waiting near the in-line type film forming apparatus. A large number of trays and carriers are used in the in-line type film forming apparatus. When some of the trays are accommodated, the movable cart is moved into the cleaning room as it is, and the cleaning room is sealed. After the cleaning chamber is evacuated to a vacuum by means of vacuum evacuation means, an etching gas suitable for removing the film adhered to the tray by etching is introduced from the etching gas introduction means, and this is turned into plasma by the plasma generation means, and the plasma is generated on the tray. The attached thin film is removed by etching. Further, depending on the type of the etching gas, the tray and the carrier are heated by a heating means instead of the plasma generating means, and the thin film attached to these is removed by chemical etching. The movable trolley transports the tray together with the carrier into the washing chamber and cleans the tray as it is, so that there is no need to apply a force to deform the surface of the tray, and it is not necessary to remove the tray from the carrier, thus improving workability. .

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 2 shows a schematic plan view of an embodiment of the present invention, and FIG. 3 shows a side view of FIG.
1 shows an in-line type film forming apparatus in which two film forming chambers 3 and 4 and an extraction chamber 5 are linearly connected via a partition valve 6. Rails 7 are laid above the insides of these chambers 2, 3, 4, and 5, and the rails 7 are also laid at the same height position in front of the charging chamber 2 and behind the unloading chamber 5. Thus, the rail 7 behind the unloading chamber 5 is circulated to the side of the charging chamber 2.
A tray 8 having substantially the same configuration as that shown in FIG. 1 is suspended from the rail 7 via a carrier 9 and moved by a driving pinion gear 10 provided above the rail 7.

The tray 8 is, for example, 800 mm thick and 8 mm thick.
It was formed of a square metal such as SUS or graphite having a size of 800 mm, or graphite, and was hung by a hanger 11 on a carrier 9 provided with a rack 12 on the upper surface and wheels 13 on the side surface. One or a plurality of substrates 14 to be subjected to a film forming process are mounted on the tray 8, and the mounting is performed by forming holes 30 in the tray 8, for example, as shown in FIG. After the substrate 14 was fitted therein, the back plate 16 was fitted and fixed. The substrate 14 is attached to the tray 8 in front of the loading chamber 2,
After leaving the in-line type film forming apparatus 1, it is removed at an appropriate place, for example, behind the extraction chamber 5. In the case shown in the drawing, a SiNx film is formed on the substrate 14 by plasma CVD in the film forming chamber 3.
And an a-Si film is formed on the film in the next film forming chamber 4 by plasma CVD.

When the film adhered to the tray 8 becomes thick due to the film formation on the substrate 14 and is to be removed, the carrier 9 is placed on a movable carriage 15 in which the tray 8 from which the substrate 14 has been removed stands by at the end of the rail 7. And carried into a washing room 16 provided at another location. The movable trolley 15 is a frame-shaped frame 1 having four legs 18 provided with casters 17.
9, a plurality of rails 20 are provided in parallel above the space of the frame 19 at the same height as the rails 7. As shown in FIG. 3, the movable cart 15 receives a plurality of trays 8 which are manually moved while moving little by little at the end of the rail 7 in the direction of the arrow.

The details of the cleaning chamber 16 are as shown in FIG. 5. The cleaning chamber 16 is connected to a hermetic chamber 24 having a vacuum exhaust port 22 connected to a vacuum pump and an etching gas inlet 23, and a high frequency power supply 25 inside the chamber. The movable carriage 15 is carried into the room through a door 27 shown in FIG. 2 which is closed in an airtight manner. As shown in FIG. 5, a plurality of the high-frequency electrodes 26 are provided at positions interposed between the plurality of trays 8 suspended on the movable cart 15 and are preferably opposed to the surfaces of the respective trays 8. As described above, the tray 8 may be provided between the two high-frequency electrodes 26 and perpendicular to them. The distance between the surface of the tray 8 and the high-frequency electrode 26 is about 20 mm.
Reference numeral 28 denotes an insulator, and reference numeral 29 denotes a grounding plate for preventing the plasma and radicals from flowing around the carrier 9 provided with a bearing or the like. When the SiNx and a-Si film are formed on the substrate 14, SF is used as an etching gas.
_Six gases are used. In addition, the transport system of the tray 8 is not limited to the above-mentioned hanging system, and the carrier may be run on a rail, and the tray may be placed on the carrier and transported.

The six trays 8 to be cleaned are
At the same time, when the vehicle is loaded on the movable carriage 15 waiting at the end of the rail 7, the movable carriage 15 is moved and carried into the washing room 16 installed at an appropriate place, and the room is evacuated to a vacuum. After introducing the etching gas and adjusting the pressure in the room,
When power is supplied from the high frequency power supply 25, plasma discharge occurs between the tray 8 and the ground potential, and radicals and ions generated in the plasma enter the surface of the tray 8 and the thin film attached thereto is deformed into the tray 8. And the surface of the tray 8 facing the electrode 26 is selectively washed. When the thin film attached to the 800 × 800 mm tray 8 is a laminated film of SiNx and a-Si film and has a thickness of 30 μm,
Adjust to 0.4 Torr by introducing SF ₆ etching gas,
When power of 13.56 MHz and 2 kW was introduced from the high frequency power supply 25, it was completely removed in about 3 hours. The following table compares the amount of deformation of the tray when the film attached to the tray is removed by glass bead blasting and the amount of deformation of the tray when the film is removed using the apparatus of the present invention. * Numbers indicate the maximum and minimum deformation of 6 trays. The processing of glass bead blasting was performed by removing the tray from the carrier and transporting the tray side by side. As is apparent from the results, in the case of glass bead blasting, the amount of deformation of the tray is so large that the position of the substrate is disturbed.

In the above embodiment, the cleaning is performed by the plasma generating means comprising the plate-like high-frequency electrode 26 connected to the high-frequency power supply 25. However, depending on the type of etching gas, for example, DC or AC is used instead of the plasma generating means. It is also possible to provide a heating means such as a surface heater connected to a power supply, and clean the thin film adhered to the tray and the carrier by chemical etching. For example, as described above, when a SiNx film is formed on the substrate 14 by the plasma CVD in the film forming chamber 3 and an a-Si film is formed on the film by the plasma CVD in the next film forming chamber 4, By introducing ClF ₃ as an etching gas from the etching gas inlet 23, the thin film adhered to the tray 8 and the carrier 9 heated by the heating means can be removed by chemical etching. In this case, the pressure in the cleaning chamber 16 is adjusted to about 30 Torr with a partial pressure of ClF ₃ and the tray is heated to 250 ° C., and when the film thickness of SiNx and a-Si is 100 to 300 μm, about 2 to 6 Cleaning was completed in a short time, and the amount of deformation of the tray after this treatment was 0.1 mm or less.

[0014] When the etching gas of ClF ₃ 100%, the pressure in the cleaning chamber 16 _{1~50Torr, N 2, Ar, ClF} 3 in He, etc.
1 to 760 Torr depending on the degree of dilution
Adjust to In addition, when the heating temperature of the tray is increased, the etching rate is increased, and it is preferable to heat the tray in the range of room temperature to 350 ° C.

[0015]

As described above, according to the present invention, a cleaning apparatus for a tray used in an in-line type film forming apparatus is provided with a movable carriage for accommodating the tray and a carrier, and the entire movable carriage for accommodating the tray and the carrier. And a cleaning chamber provided with a vacuum exhaust unit, an etching gas introducing unit, and a plasma generating unit or a heating unit, so that various thin films adhered to the tray can be removed without deforming the tray. Since it is not necessary to remove the carrier from the carrier, the cleaning operation is simplified.

[Brief description of the drawings]

FIG. 1 is an overall side view of a conventional tray and carrier.

FIG. 2 is an overall schematic plan view of an embodiment of the present invention.

FIG. 3 is an overall schematic side view of FIG. 2;

FIG. 4 is an enlarged sectional view of a tray.

FIG. 5 is an enlarged cut-away side view of the cleaning room.

FIG. 6 is a schematic cutaway plan view of a modified example of the cleaning chamber.

[Explanation of symbols]

1 In-line type film forming equipment 7, 20 rails
8 tray 9 carrier 13 wheels
14 Substrate 15 Moving trolley 16 Cleaning room
22 Vacuum exhaust port 23 Etching gas inlet 26 Plasma generator

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuyuki Ito 523 Yokota, Yamatake-cho, Yamatake-gun, Chiba Japan Vacuum Engineering Co., Ltd. (72) Inventor Takeshi Yonezaki 523 Yokota, Yamatake-cho, Yamatake-gun, Chiba Chiba Super Materials Laboratory Co., Ltd. (72) Inventor Masanori Hashimoto 523, Yamatake-cho, Yamatake-gun, Chiba Prefecture Japan Vacuum Engineering Co., Ltd. Inside Chiba Super Materials Laboratory Co., Ltd. (72) Inventor Hisazo Nakamura 523 Yokota, Yamatake-cho, Yamatake-gun, Chiba Prefecture Japan Vacuum Engineering Co., Ltd. Chiba Super Materials Laboratory Co., Ltd. (56) References JP-A-3-166373 (JP, A) Kaihei 5-217975 (JP, A) JP-A 3-14148 (JP, U) JP-A 63-32689 (JP, U) (58) Fields surveyed (In t.Cl. ⁷ , DB name) C23F 4/00 C23C 14/00 C23C 16/50 H01L 21/304 648

Claims (3)

(57) [Claims] In an in-line type film forming apparatus for forming a film on a substrate by sequentially moving a tray on which a substrate is mounted in a plurality of film forming chambers by a carrier, the tray from which the film is formed is removed together with the carrier. An in-line type film forming apparatus comprising: a movable carriage for housing therein; and a cleaning chamber for accommodating the entire movable carriage for housing the tray and the carrier, and including a vacuum exhaust unit, an etching gas introducing unit, and a plasma generating unit. Tray cleaning device in equipment. 2. The apparatus for cleaning a tray in an in-line type film forming apparatus according to claim 1, further comprising means for heating a tray and a carrier in place of said plasma generating means. 3. The tray is attached to a carrier having wheels running on rails provided in a film forming apparatus and moves.
2. The tray cleaning apparatus according to claim 1, wherein the movable trolley has a plurality of rails, each of which carries a carrier having a tray mounted thereon and moves into the cleaning chamber.