JP2000019721A - Reticule container, exposure method and manufacture of device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform exposure in a state of inert gas being filled at high purity in a reticule and its peripheral part by conveying in a state of inert gas being filled inside a container enclosing the reticule with a pellicle. SOLUTION: A reticule 1 is placed on a cassette tray 11 and supported by a positioning face 12 and a placing face 13. A cassette cover 14 and the tray 11 are engaged at an engaging part 15. A transport container is provided with a body 16 and a cover 17, and these members are engaged by an engaging thread part 18. The body 16 of the transport container is engaged with the cassette cover 14 at a face 19. A tube 21 leads gas into a female side joint 22 from an inert gas cylinder. A male side joint 23 is engaged with the female side joint 22. When a knob 25 for opening/closing the conduit of a throttle valve 24 is opened, inert gas flows in from the cylinder. The throttle valve 24, a tube 27, a filter 28, a tube 31 and the transport container body 16 are respectively connected by connectors 26, 29, 30, 32. The filter 28 captures refuse in a gas conduit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of placing a reticle with a pellicle used in a semiconductor exposure apparatus in an inert gas atmosphere throughout the entire exposure process.

[0002]

2. Description of the Related Art Conventionally, a reticle with a pellicle not filled with an inert gas is simply placed in a reticle storage container, and the reticle is mounted on a stepper. Only the excimer laser and the illumination optical system were filled with the inert gas in the stepper, and the inert gas was not filled around the reticle mounting portion. Known documents disclosing such a technique include JP-A-3-18852, JP-A-5-243116, and JP-A-6-26.
0386 and JP-A-9-246140.

[0003]

In a stepper using an excimer laser beam as the exposure light, unless an inert gas is filled in the illumination optical system, a compound such as ammonium sulfate adheres to an optical element in the optical system, resulting in "cloudy". "State. Then, the exposure light is scattered and absorbed by the ammonium sulfate, so that the light transmittance in the illumination optical system is reduced. Due to the structure of the stepper, it is easy to fill the inert gas with the illumination optical system as a closed structure. On the other hand, the reticle, which is also an optical element, and its periphery should be originally made to have a sealed structure and filled with an inert gas. However, since the reticle has to be replaced, it is very difficult to make it a sealed structure.

Further, if a space formed by a pellicle film, a pellicle frame and a reticle is not filled with an inert gas at the stage of attaching the pellicle film, this space will not be in an inert gas atmosphere. . However, the reticle is also one of the optical elements, and it is naturally preferable to place the reticle in an inert gas atmosphere in order to avoid the attachment of a compound such as ammonium sulfate. However, there is a problem that if the inert gas is left alone in ordinary air in a state filled with the inert gas, the external air is mixed through the pellicle film and the purity of the inert gas is reduced.

SUMMARY OF THE INVENTION In view of the above-mentioned problems in the prior art, it is a main object of the present invention to perform exposure in a state where a highly pure inert gas is filled in and around a reticle with a pellicle.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to provide:
This was achieved by the reticle container and exposure method described below. That is, the reticle container of the present invention is a container for storing and transporting a reticle with a pellicle, and has a structure capable of transporting a reticle with an inert gas filled therein.

[0007] The reticle container of the present invention has a structure such that a reticle with a pellicle can be transported in a state where the inside of the container is filled with an inert gas. As such a structure, it is only necessary that the container has a closed structure and that there is a space in which a reticle with a pellicle can be stably stored and transported, and it is preferable that a gas introduction port and an exhaust port are further provided.

It is preferable that the space between the pattern surface of the reticle and the pellicle stretched thereon is filled with an inert gas. The pellicle is usually stretched over the pattern surface of the reticle via a frame as shown in FIG.

Further, in the exposure method of the present invention, a reticle with a pellicle is housed in a reticle container of the present invention filled with an inert gas, transported to an exposure apparatus, and a reticle with a pellicle is mounted to perform exposure. It is characterized by.

The order of filling the inert gas is as follows. First, the reticle is filled with the inert gas at the stage of attaching the pellicle to the reticle, and the reticle is stored in a reticle container. Then, the air in the container is replaced with the inert gas. Is preferred, while
A reticle with a pellicle that is not filled with an inert gas is first housed in a reticle container, and then an inert gas is passed through the container. It is also conceivable to replace the air.

According to the method of the present invention, a reticle with a pellicle filled with an inert gas can be placed in an inert gas space while being transported to an exposure apparatus (stepper) and also during a standby time until the reticle is mounted. As a result, the purity of the inert gas filled in the reticle with a pellicle can be maintained.

In the exposure method of the present invention, it is desirable that the reticle with a pellicle is placed in an inert gas even during exposure. In particular, in the stepper, it is desirable to fill both the periphery of the reticle surface and the space between the wafer surface and the final element on the projection lens side with an inert gas. Also,
Exposure is preferably performed using excimer laser light.

Further, the present invention relates to a device manufacturing method characterized by manufacturing a device by a manufacturing process including the exposure method of the present invention.

[0014]

EXAMPLES First Embodiment FIG. 1 is a partial cross-sectional view of a reticle container of the present invention for containing and conveying the pellicle reticle with. In the figure, 1
Is a reticle, 2 is a pellicle frame, 3 is a pellicle, and these three parts are mutually bonded. 4 is a space surrounded by these parts.

The reticle is mounted on a cassette tray 11 and is supported by a positioning surface 12 and a mounting surface 13. Reference numeral 14 denotes a cassette lid, which is engaged with the tray 11 by an engaging portion 15.

The transport container of the present invention has a main body 16 and a lid 17, and these members are engaged by an engaging screw portion 18. The body 16 of the transport container is engaged with the cassette lid 14 at the surface 19. Reference numeral 20 denotes a handle of the lid 17 of the transport container.

Next, an inert gas introduction system will be described. 21 is a tube for introducing the same gas into the female joint 22 from an inert gas cylinder (not shown), 23 is a male joint that engages with the female joint 22, 24 is a throttle valve, and 25 is an open / close pipe of a throttle valve 24. This is a handle for opening, and the inert gas flows from the cylinder when opened, and stops when closed.

Reference numeral 26 denotes a connector for connecting the throttle valve 24 and the tube 27. The connector 26 is engaged with the throttle valve 24 by a thread. Reference numeral 28 denotes a filter for capturing dust in the inert gas pipe. 29 and 30 are connectors, each of which is a tube 2
7 and 31 are connected to the filter 28. Reference numeral 32 denotes a connector for connecting the tube 31 and the transport container main body 16.
6 is engaged with a screw portion.

Next, the gas discharge system will be described. 41
Is a connector for connecting the transport container main body 16 and the tube 42, and is engaged with the main body 16 by a screw portion. Reference numeral 43 denotes a connector for connecting the tube 42 and the throttle valve 44, and the throttle valve 44 is engaged with a screw portion. Reference numeral 45 denotes a handle for opening and closing the pipeline of the throttle valve 44, and is opened when the air in the transport container is replaced with an inert gas. When transporting after filling with the inert gas, the handle 25 on the inflow side and the handle 45 on the ejection side are closed, and the female joint 22 is separated from the male joint 23 for transportation. Injection side handle 45
Is closed to prevent air from flowing into the container. 46 is a substrate. Since the throttle valve 24 is lightweight, it may be transported without the substrate 46, or may be transported together with this substrate.

Second Embodiment FIG. 2 is a schematic view showing an entire stepper used in the exposure method of the present invention. Reference numeral 50 denotes an illumination optical system, 51 denotes a reticle unit, 52 denotes a reticle transport unit, 53 denotes an electrical box, Reference numeral 54 denotes a projection lens, 55 denotes a wafer transfer system, and 56 denotes an XY stage and mount. In this figure,
In particular, an inert gas injection port is provided between the illumination optical system and the reticle unit, between the reticle unit and the projection lens, and between the projection lens and the XY stage to fill the inert gas. In this figure, the route is not shown.

Third Embodiment Next, an embodiment of a device manufacturing method utilizing the above-described exposure method will be described. FIG. 3 shows a micro device (IC
1 shows a flow of manufacturing semiconductor chips such as LSIs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, and the like. In step 1 (circuit design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. Step 3
In (wafer manufacture), a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process and uses the prepared mask and wafer to
An actual circuit is formed on a wafer by a lithography technique. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and an assembly process (dicing,
Bonding), a packaging step (chip encapsulation), and the like. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 4 shows the wafer process (step 4).
The detailed flow of is shown. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. In step 15 (resist processing), a resist is applied to the wafer. In step 16 (exposure), the circuit pattern of the mask (reticle) is arranged in a plurality of shot areas of the wafer and printed by the above-described exposure method of the present invention. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of this embodiment, it is possible to manufacture a large-sized device, which was conventionally difficult to manufacture, with high efficiency.

[0024]

As described above, according to the present invention,
The reticle with the pellicle filled with the inert gas can be placed in the inert gas space while being transported to the exposure apparatus (stepper), and also during the waiting time until the reticle is mounted. It is no longer said that the air is mixed and the inert gas purity is reduced. Therefore,
Irradiation with exposure light such as excimer laser light does not cause impurities such as ammonium sulfate to adhere to the pellicle, so that the exposure light is no longer scattered or absorbed by the pellicle portion.

Further, by filling the space between the wafer surface and the final element on the projection lens side with an inert gas, the exposure light is not scattered or absorbed in the final element portion on the projection lens side. Was. Therefore, a highly integrated device can be manufactured with high efficiency.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a reticle container storing a reticle with a pellicle according to a first embodiment.

FIG. 2 is an overall schematic view of a stepper according to a second embodiment.

FIG. 3 is a flowchart of a device manufacturing method according to a third embodiment.

FIG. 4 is a detailed flowchart of a wafer process of a device manufacturing method according to a third embodiment.

[Explanation of symbols]

1: Reticle, 2: Frame, 3: Ricle, 16: Storage container body, 17: Storage container lid, 22: Female joint, 23:
Male fitting, 24: throttle valve, 25: handle, 28:
Filter, 44: throttle valve, 45: handle.

Claims (6)

[Claims] 1. A reticle container for storing and transporting a reticle with a reticle, wherein the reticle container has a structure capable of transporting a reticle with an inert gas filled therein. 2. The container according to claim 1, wherein an inert gas is filled between a pattern surface of the reticle and the pellicle placed on the reticle. 3. A reticle with a pellicle is housed in the reticle container according to claim 1 filled with an inert gas, transported to an exposure apparatus, and mounted with the reticle with the pellicle to perform exposure. Characteristic exposure method. 4. The exposure method according to claim 3, wherein the reticle with a pellicle is placed in an inert gas even during exposure. 5. The exposure method according to claim 3, wherein the exposure is performed using an excimer laser beam. 6. A device manufacturing method, wherein a device is manufactured by a manufacturing process including the exposure method according to claim 3.