Production and treatment method for foreign matter attached to Pellicle film of mask

Abstract

The invention relates to mask production, in particular to a method for producing and processing foreign matters attached to a Pellicle film of a mask, which comprises the following steps of: constructing a Pellicle film foreign matter exposure projection model, fitting the Pellicle film foreign matters and illumination spots on the basis of the Pellicle film foreign matter exposure projection model, and determining a foreign matter diameter tolerance threshold according to a fitting result. The actually generated mask is processed according to the foreign matter diameter tolerance threshold value; according to the technical scheme provided by the invention, the defect that foreign matters attached to the Pellicle film in the mask production process cannot be effectively judged and treated in the prior art can be effectively overcome.

Description

Technical Field

[0001] The invention relates to mask production, and in particular to a production and processing method for foreign matter attached to a mask Pellicle film. Background Art

[0002] In the production process of the mask, in order to improve the cleanliness of the product, it is required to attach a layer of dust-proof film, namely Pellicle film, to the surface of the mask substrate. Pellicle film can not only greatly improve the cleanliness of the mask, but also significantly extend the service life of the mask. For downstream panel manufacturers, the use of Pellicle film can effectively guarantee the yield and stability of their production. However, for upstream mask research and development, design and production companies, extremely high cleanliness needs to be ensured during the Pellicle film bonding process. The conventional cleanliness level must meet level 10, and high-standard operating requirements must be met during operation to eliminate all possibilities of introducing foreign matter, so as to ensure the success rate of Pellicle film bonding.

[0003] At present, there are relatively few Pellicle film manufacturers available for mask production (only three suppliers in the world), and the quality of their supplies varies greatly. In addition, suppliers mainly use manual visual inspection to check whether there are foreign objects attached to the Pellicle film before shipment, which poses a high risk of missed inspections and brings great risk factors to the quality of mask production. During the use of Pellicle film, the most serious problem is foreign objects on the film surface. The attachment of foreign objects not only brings the possibility of contamination to the mask substrate, but also affects the chrome layer pattern of the mask when the panel customer is exposed.

[0004] How to effectively avoid the above problems, identify and deal with foreign matter attached to the Pellicle film during the mask production process, and ensure the quality of mask production is a challenge for the entire mask production and manufacturing industry. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a production and processing method for foreign matter attached to the plecle film of a mask, which can effectively overcome the defect of the prior art that it is unable to effectively determine and process foreign matter attached to the plecle film during the mask production process.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] A production and processing method for foreign matter attached to a plecle film of a mask plate, constructing an exposure projection model for foreign matter on the plecle film, fitting the foreign matter on the plecle film and the illumination spot based on the exposure projection model for foreign matter on the plecle film, determining a foreign matter diameter tolerance threshold according to the fitting result, and processing the actually generated mask plate according to the foreign matter diameter tolerance threshold.

[0010] Preferably, the construction of the Pellicle film foreign body exposure projection model comprises:

[0011] In the Pellicle film foreign body exposure projection model, the diameter is The foreign matter on the Pellicle film is exposed and projected onto the mask substrate to form a dot-shaped object with a size of D, namely the illumination spot.

[0012] Preferably, the fitting of the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model comprises:

[0013] Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign body with a unit diameter is fitted to obtain the following formula:

[0014]

[0015] Among them, δ is the δ value of the lighting system, which is fixed at 1.0. NA is the lens aperture coefficient, NA = 0.1; β is the lens magnification, β = 1.0; H is the pellicle film thickness, in mm; n is the medium refractive index, n = 1.0; is the diameter of foreign matter on the pellicle membrane, in μm.

[0016] Preferably, the fitting of the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model comprises:

[0017] Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body Fitting the illumination spot size D formed by its exposure projection gives the following formula:

[0018]

[0019] Where D is the diameter The illumination spot size formed by the exposure projection of foreign matter on the Pellicle film is in nm.

[0020] Preferably, determining the foreign body diameter tolerance threshold according to the fitting result includes:

[0021] According to the diameter of foreign matter on the Pellicle membrane The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign matter per unit diameter is fitted, and the diameter of the Pellicle film foreign matter is The corresponding fitting curve is obtained by fitting the fitting relationship with the illumination spot size D formed by the exposure projection, and the fitting curve is comprehensively analyzed to determine the tolerance threshold of the foreign body diameter;

[0022] Among them, the foreign body diameter tolerance threshold is 20μm.

[0023] Preferably, the processing of the actually generated mask according to the foreign matter diameter tolerance threshold comprises:

[0024] In the actual production of the mask, the actual diameter of the foreign matter on the Pellicle film is obtained by using the detection equipment and compared with the foreign matter diameter tolerance threshold;

[0025] If the actual diameter of the foreign body on the Pellicle membrane is smaller than the tolerance threshold of the foreign body diameter, it is considered as a qualified product, otherwise it is considered as an unqualified product and is rejected.

[0026] (III) Beneficial effects

[0027] Compared with the prior art, the present invention provides a production and processing method for foreign matter attached to the Pellicle film of a mask plate, constructs an exposure projection model for foreign matter on the Pellicle film, and analyzes the impact of foreign matter on the customer's use of the Pellicle film with different diameters based on the exposure projection model of foreign matter on the Pellicle film. At the same time, the diameter of the foreign matter on the Pellicle film is fitted with the illumination spot formed by the exposure projection of the foreign matter on the Pellicle film with a unit diameter, and the diameter of the foreign matter on the Pellicle film is fitted with the illumination spot size formed by its exposure projection. By obtaining the corresponding fitting curve and performing a comprehensive analysis, the tolerance threshold of the foreign matter diameter is determined, which can be directly used for the judgment of foreign matter attached to the Pellicle film, so that industry personnel can quickly evaluate and respond to the impact caused by the exposure projection of foreign matter on the Pellicle film, and effectively improve the production quality and efficiency of the mask plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a schematic diagram of the process of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of the mask substrate and the Pellicle film;

[0031] Figure 3 It is a schematic diagram of the projection model of foreign matter exposure of Pellicle film in the present invention;

[0032] Figure 4 It is a fitting curve diagram obtained by fitting the diameter of foreign matter on the Pellicle film and the illumination spot formed by the exposure projection of foreign matter on the Pellicle film with a unit diameter in the present invention;

[0033] Figure 5 This is a fitting curve diagram obtained by fitting the diameter of foreign matter on the Pellicle film and the illumination spot size formed by its exposure projection in the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] A production and processing method for foreign matter attached to a mask pellicle film, such as Figure 1 As shown, ① construct a Pellicle film foreign matter exposure projection model, fit the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model, determine the foreign matter diameter tolerance threshold according to the fitting result, and process the actually generated mask according to the foreign matter diameter tolerance threshold.

[0036] ①Construct the Pellicle film foreign body exposure projection model, such as Figure 3 As shown, including:

[0037] In the Pellicle film foreign body exposure projection model, the diameter is The foreign matter on the Pellicle film is exposed and projected onto the mask substrate to form a dot-shaped object with a size of D, namely the illumination spot.

[0038] ②1) Fitting the Pellicle film foreign matter and illumination spot based on the Pellicle film foreign matter exposure projection model, including:

[0039] Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign body with a unit diameter is fitted to obtain the following formula:

[0040]

[0041] Among them, δ is the δ value of the lighting system, which is fixed at 1.0. NA is the lens aperture coefficient, NA = 0.1; β is the lens magnification, β = 1.0; H is the thickness of the Pellicle film, only 5.9mm and 7mm; n is the medium refractive index, n = 1.0; is the diameter of foreign matter on the pellicle membrane, in μm.

[0042] 2) Fitting the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model, including:

[0043] Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body Fitting the illumination spot size D formed by its exposure projection gives the following formula:

[0044]

[0045] Where D is the diameter The illumination spot size formed by the exposure projection of foreign matter on the Pellicle film is in nm.

[0046] like Figure 2 As shown in the figure, the function of Pellicle film is to improve the cleanliness of the mask and extend the service life of the mask. Currently, there are only two thicknesses of Pellicle film in use. One is 5.9mm, which is used in very small quantities and is only used for a small amount of special materials; the other is 7mm, which is the mainstream product design in production and is used in large quantities.

[0047] ③ Determine the foreign body diameter tolerance threshold based on the fitting results, including:

[0048] According to the diameter of foreign matter on the Pellicle membrane The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign matter per unit diameter is fitted, and the diameter of the Pellicle film foreign matter is The corresponding fitting curve is obtained by fitting the fitting relationship with the illumination spot size D formed by the exposure projection, and the fitting curve is comprehensively analyzed to determine the tolerance threshold of the foreign body diameter;

[0049] Among them, the foreign body diameter tolerance threshold is 20μm.

[0050] like Figure 4 The figure shows the diameter of foreign matter on the Pellicle membrane. The fitting curve is obtained by fitting the illumination spot ΔE formed by the exposure projection of the Pellicle film foreign body with a unit diameter. Based on theoretical analysis, it can be obtained that when the diameter of the Pellicle film foreign body is After that, the illumination spot ΔE (%) shows a sharp upward trend. Therefore, in the production process of the mask, it is necessary to ensure that the diameter of the foreign matter on the Pellicle film is Otherwise, the production quality of the mask will be greatly affected.

[0051] like Figure 5 The figure shows the diameter of foreign matter on the Pellicle membrane. The fitting curve diagram obtained by fitting the illumination spot size D formed by its exposure projection. Figure 5 The illumination spot ΔE (%) is converted into a more obvious illumination spot size D (nm). This conversion can show in a more intuitive way how large the illumination spot will be when the Pellicle film foreign matter is projected on the chrome layer of the mask. Figure 4 Same, foreign body diameter in Pellicle membrane When it reaches 20μm, the illumination spot size D increases sharply, so the diameter of the Pellicle film foreign matter needs to be strictly controlled during the production process of the mask.

[0052] ④ Process the actually generated mask according to the foreign body diameter tolerance threshold, including:

[0053] In the actual production of the mask, the actual diameter of the foreign matter on the Pellicle film is obtained by using the detection equipment and compared with the foreign matter diameter tolerance threshold;

[0054] If the actual diameter of the foreign body on the Pellicle membrane is smaller than the tolerance threshold of the foreign body diameter, it is considered as a qualified product, otherwise it is considered as an unqualified product and is rejected.

[0055] The technical solution of the present application can, on the one hand, provide guidance for the actual production of mask plates, and on the other hand, provide a definite quality indicator when purchasing raw materials of Pellicle films, namely, the diameter of foreign matter in Pellicle films. Pellicle film is unacceptable in the mask production process.

[0056] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A production and processing method for foreign matter attached to a mask pellicle film, characterized in that: An exposure projection model for foreign matter on the Pellicle film is constructed. Foreign matter on the Pellicle film and the illumination spot are fitted based on the exposure projection model. The tolerance threshold of foreign matter diameter is determined according to the fitting result. The actually generated mask is processed according to the tolerance threshold of foreign matter diameter.

2. The method for producing and treating foreign matter attached to the mask pellicle film according to claim 1, characterized in that: The method of constructing a Pellicle film foreign body exposure projection model comprises: In the Pellicle film foreign body exposure projection model, the diameter is The foreign matter on the Pellicle film is exposed and projected onto the mask substrate to form a dot-shaped object with a size of D, namely the illumination spot.

3. The method for processing foreign matter attached to the mask pellicle film according to claim 1, characterized in that: The fitting of the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model includes: Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign body with a unit diameter is fitted to obtain the following formula: Among them, δ is the δ value of the lighting system, which is fixed at 1.

0. NA is the lens aperture coefficient, NA = 0.1; β is the lens magnification, β = 1.0; H is the pellicle film thickness, in mm; n is the medium refractive index, n = 1.0; is the diameter of foreign matter on the pellicle membrane, in μm.

4. The method for producing and treating foreign matter attached to the mask pellicle film according to claim 3, characterized in that: The fitting of the Pellicle film foreign matter and the illumination spot based on the Pellicle film foreign matter exposure projection model includes: Based on the Pellicle film foreign body exposure projection model, the diameter of the Pellicle film foreign body Fitting the illumination spot size D formed by its exposure projection gives the following formula: Where D is the diameter The illumination spot size formed by the exposure projection of foreign matter on the Pellicle film is in nm.

5. The method for processing foreign matter attached to the mask pellicle film according to claim 4, characterized in that: Determining the foreign body diameter tolerance threshold according to the fitting result includes: According to the diameter of foreign matter on the Pellicle membrane The illumination spot ΔE formed by the exposure projection of the Pellicle film foreign matter per unit diameter is fitted, and the diameter of the Pellicle film foreign matter is The corresponding fitting curve is obtained by fitting the fitting relationship with the illumination spot size D formed by the exposure projection, and the fitting curve is comprehensively analyzed to determine the tolerance threshold of the foreign body diameter; Among them, the foreign body diameter tolerance threshold is 20μm.

6. The method for processing foreign matter attached to the mask pellicle film according to claim 1, characterized in that: The processing of the actually generated mask according to the foreign matter diameter tolerance threshold comprises: In the actual production of the mask, the actual diameter of the foreign matter on the Pellicle film is obtained by using the detection equipment and compared with the foreign matter diameter tolerance threshold; If the actual diameter of the foreign body on the Pellicle membrane is smaller than the tolerance threshold of the foreign body diameter, it is considered as a qualified product, otherwise it is considered as an unqualified product and is rejected.

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