TWM596366U - Photomask protection box structure - Google Patents

Abstract

A mask protection box structure includes at least a base, and a mask system can be placed on the base, wherein the base is covered with an upper cover body, and the upper end of the upper cover body is provided with a transparent cover Film, so when the mask protection box structure is used in a DUV mask surface inspection machine, it can penetrate the transparent film through a wavelength of 193 nm to detect whether the surface of the mask body With foreign body.

Description

Photomask protection box structure

This creation relates to a mask protection box structure, especially a method and mask assembly capable of detecting whether there are foreign objects on the surface of the mask body before the EUV lithography process.

According to the current semiconductor device manufacturing technology, the circuit pattern of the semiconductor device is transferred to the surface of the silicon wafer through a lithography process, specifically, a light source of a specific wavelength is projected through a photomask Way, the circuit pattern is transferred to the surface of the silicon wafer. In order to double the number of semiconductor devices such as transistors per unit area, reducing the line width of semiconductor circuits is the main technical solution. At present, deep ultraviolet light (DUV) with a wavelength of 193 nm is used as the exposure light source for the lithography process.

In order to obtain a smaller line width, it is necessary to use a light source with a shorter wavelength for exposure. Therefore, in order to make a finer line width structure, the extreme ultraviolet light source with a wavelength of 13.5 nanometers or EUV for short is the only one in the next stage. Using light sources, according to estimates, the maximum physical limit of the current ArF 193 nanometer light source is a line width of 10 nm. If it is below 7 nm, it is not a EUV extreme ultraviolet light source.

Due to the miniaturization of semiconductor devices, in the manufacturing process of semiconductor devices, defects in the photomask will cause distortion or deformation of the circuit pattern on the surface of the silicon wafer. Even defects of only nanometer size, such as 20 nm to 200 nm, will cause semiconductor circuit pattern defects. damage.

One of the known causes of defects in the photomask is that the surface of the photomask is contaminated with particles (contamination particles); in order to maintain the quality of the photomask during use, a conventional method is to provide a frame with a mask protective film (pellicle) on the surface of the photomask to prevent pollutants from falling on the photomask Contamination particles are formed on the surface.

In addition, the photomask needs to avoid the pollution of the photomask during transportation and storage, and to avoid the impact of particles such as collision or friction on the cleanliness of the photomask, so the photomask must be placed in a light Transport and store in the hood box to protect the hood from contamination.

However, even if the above frame and mask box are used, it may still cause pollution on the surface of the mask, so the inspection of the surface of the mask becomes very important. At present, most of the inspection of the surface of the mask is to use the DUV mask surface inspection machine, mainly When the deep ultraviolet light with a wavelength of 193 nanometers passes through the film on the frame, the surface of the photomask can be irradiated for detection.

However, after transportation and storage of the photomask, the photomask still needs to be taken out for inspection. In this process, there will be a certain risk of pollution. Therefore, if the transparent film sheet can be combined and positioned on the upper end of the structure of the photomask protection box, The mask can be moved into the DUV mask surface inspection machine to detect whether there is foreign matter on the surface of the mask body during transportation. This will avoid accidental contamination caused by the mask removal and detection. Creation should be the best solution.

A mask protection box structure includes at least a base, and a mask system can be placed on the base, characterized in that an upper cover body is used to cover the base, and the upper cover The upper end of the body is provided with a positioning groove, and a penetrating inner frame is provided in the center of the upper cover body; a top cover member is provided with a downward positioning frame strip; and a transparent film piece is disposed on the upper cover body and Between the top cover members, and the positioning frame strip of the top cover member can be attached to the transparent film sheet and inserted downward and fixed in In the positioning groove, so that the transparent film sheet can be stably held between the upper cover body and the top cover member; and the upper cover body is combined with the transparent film sheet and the top cover member and covers the After being mounted on the base, it can penetrate the transparent film through a wavelength of 193 nanometers in a DUV mask surface inspection machine to detect whether there is foreign matter on the surface of the mask body.

More specifically, the transparent film sheet is made of fluorine-containing polymer film material.

More specifically, an EUV mask protection unit can be combined on the mask body. The EUV mask protection unit includes a frame and a non-transparent film attached to the frame, and the DUV light The mask surface inspection machine can penetrate the transparent film through a wavelength of 193 nm to detect whether there is foreign matter on the surface of the non-transparent film of the EUV mask protection unit.

More specifically, the non-transparent thin film of the EUV mask protection unit is made of an inorganic thin film material mainly composed of silicon.

1: pedestal

2: Upper cover body

21: positioning groove

22: Penetrate the inner frame

3: Top cover

31: positioning frame

4: Transparent film

5: Mask body

51: Surface

6: EUV mask protection unit

61: Frame

62: Non-transparent film

7: DUV photomask surface inspection machine

71: Detect laser source

711: DUV detection beam

72: detector

[Figure 1A] This is a schematic exploded view of the structure of the photomask protection box of this creation.

[Figure 1B] This is a schematic diagram of the combined structure of the original photomask protection box structure.

[Figure 1C] This is a schematic diagram of the cross-sectional structure of the original photomask protection box structure.

[Figure 2] It is a schematic diagram of the implementation of the inspection of the surface of the mask of the structure of the creative mask protection box.

[Figure 3] This is a schematic diagram of the implementation of the EUV film surface inspection of the original photomask protection box structure.

For other technical contents, features and functions of this creation, please refer to the following diagrams The detailed description of the preferred embodiment will be clearly presented.

Please refer to Figures 1A~1C, which are the structural schematic diagram, the combined structural schematic diagram and the cross-sectional structural schematic diagram of the creation of the photomask protection box structure. As can be seen from the figure, the photomask protection box structure includes a base 1 and an upper cover body 2 1. A top cover member 3 and a transparent film sheet 4, as shown in FIG. 2, a photomask body 5 is placed on the surface of the base 1.

The upper cover body 2 is used to cover the base to form a box body through the upper cover body 2 and the base 1 to facilitate carrying the photomask body 5, and the upper end of the upper cover body 2 has an upper end system A positioning groove 21 is provided, and a penetrating inner frame 22 is provided in the center of the upper cover body.

The top cover member 3 is an aluminum frame, and the top cover member 3 has a positioning frame 31 facing downward.

The transparent film sheet 4 is made of fluorine-containing polymer film material, and the transparent film sheet 4 is pressed down into the positioning groove 21 through the positioning frame 31 of the top cover 3 to make the transparent film The sheet 4 is sandwiched between the top cover 3 and the mask body 5.

As shown in Fig. 2, after the mask box is transported to a DUV mask surface inspection machine 7, the laser source 71 (Laser Source) of the DUV mask surface inspection machine can be detected by a DUV The light beam 711 (wavelength of 193 nm) penetrates the transparent film sheet 4 at an angle to enter the surface 51 of the reticle body 5 and is reflected to a detector 72 (Detector) to perform on the surface 51 of the reticle body 5 Check for contamination particles.

In addition, if the lithography process is to be performed at a wavelength of 13.5 nanometers, an EUV mask protection unit 6 can also be combined on the surface 51 of the mask body 5, the EUV mask protection unit 6 is shown in FIG. 3 It includes a frame 61 and a non-transparent thin film 62 attached to the frame 61 (the non-transparent thin film 62 is made of an inorganic thin film material mainly composed of silicon). Before the lithography process, it can also The The reticle is transported to the DUV reticle surface inspection machine, and a transparent DUV detection beam 711 (193 nm wavelength) is passed through the transparent film sheet 4 to detect the surface of the non-transparent film sheet 62 for contamination particles.

The EUV mask protection unit 6 is integrated on the surface 51 of the mask body 5 and can be combined with a robotic arm under a vacuum environment, or a robotic arm in the DUV mask surface detection machine The device combines the EUV mask protection unit 6 on the surface 51 of the mask body 5.

The structure of the photomask protection box provided by this creation has the following advantages when compared with other conventional technologies:

(1) This creation can combine the structure of the photomask protection box with the transparent film sheet, so that the photomask can be directly moved into the DUV photomask surface inspection machine to detect whether there are foreign objects on the surface of the photomask body during transportation. In this way, accidental contamination caused by taking out the photomask for inspection can be avoided.

(2) This creation can be transported to the DUV mask surface inspection machine through the mask box before the EUV lithography process to detect whether there is a non-transparent film on the surface of the mask body or the EUV mask protection unit foreign body.

This creation has been disclosed as above through the above-mentioned embodiments, but it is not intended to limit this creation. Anyone who is familiar with this technical field and has general knowledge should understand the aforementioned technical features and embodiments of this creation without departing from this creation. No changes or modifications can be made within the spirit and scope, so the scope of patent protection for this creation is subject to the definition as defined in the claims attached to this specification.

1: pedestal

2: Upper cover body

21: positioning groove

22: Penetrate the inner frame

3: Top cover

4: Transparent film

Claims (4)

A photomask protection box structure includes at least a base, and a photomask system can be placed on the base, characterized in that an upper cover body is used to cover the base, and the upper cover The upper end of the body is provided with a positioning groove, and a penetrating inner frame is provided in the center of the upper cover body; a top cover member is provided with a downward positioning frame strip; and a transparent film piece is disposed on the upper cover body and Between the top cover members, and the positioning frame strip of the top cover member can be attached to the transparent film sheet and inserted downwardly and fixed in the positioning groove, so that the transparent film sheet can be stably held on the upper cover Between the body and the top cover member; and after the upper cover body is combined with the transparent film sheet and the top cover member and covered on the base, it can pass through a 193 nanometer in a DUV photomask surface inspection machine The wavelength of meters penetrates the transparent film sheet to detect whether there is foreign matter on the surface of the photomask body. The mask protection box structure according to claim 1, wherein the transparent film sheet is made of a fluorine-containing polymer film material. The reticle protection box structure according to claim 1, wherein an EUV reticle protection unit can be further combined on the reticle body, and the EUV reticle protection unit includes a frame and a non-transparent attached to the frame The film sheet, in the DUV mask surface inspection machine, can penetrate the transparent film sheet through a wavelength of 193 nm to detect whether there is foreign matter on the surface of the non-transparent film sheet of the EUV mask protection unit. The mask protection box structure according to claim 3, wherein the non-transparent thin film of the EUV mask protection unit is made of an inorganic thin film material mainly composed of silicon.

Images