TWI571698B - Method for manufacturing EUV mask inorganic protective film module - Google Patents

Description

EUV reticle inorganic protective film assembly manufacturing method

The invention relates to a method for manufacturing an EUV mask inorganic protective film assembly, in particular to deposit a tantalum nitride layer on two surfaces of a graphene layer, and the tantalum nitride layer can be used for clamping the graphene. And protecting the graphene layer to increase the structural strength of the graphene layer.

The circuit pattern of the semiconductor element is a transfer of the circuit pattern to the surface of the germanium wafer by a lithography process using a photomask and an exposure technique. The defect of the mask may cause distortion or deformation of the circuit pattern on the surface of the wafer. One of the reasons for the known defect of the mask is that the surface of the mask is contaminated by contamination particles, so that the circuit pattern on the surface of the wafer is Distortion or distortion occurs in the presence of contaminating particles; in order to maintain the quality of the reticle during use, a known method is to provide a reticle protective film module on the surface of the reticle to prevent deposition of contaminating particles. Direct contact with the reticle surface; the construction of the reticle protective film assembly basically comprises a transparent protective film and a frame, and the protective film provides a physical barrier against external pollution for preventing escape from the environment and gas (outgassing) ) or other contaminant particles that contaminate the surface of the reticle.

Depending on the width of the circuit pattern, the wavelength of the light source used in the exposure technique is also different. For different wavelengths of exposure light, the protective film must have sufficient transmission to ensure The yield of the micro-film process, the transmittance of the protective film depends on the thickness of the protective film, the type of anti-reflective coating, the light absorption of the material of the protective film, and the light source used in the wafer exposure machine or stepper. The wavelength of nitrocellulose is the material of the film originally used, and the protective film is used for g-line (436nm) or i-line (365nm), and the fluorinated polymer is used for KrF (248nm). Or ArF (193nm) wafer exposure machine or broadband projection wafer stepper. With the miniaturization of circuit patterns, the lithography process using ultra-ultraviolet light (EUV) with a wavelength of only 13.5 nanometers (nm) as an exposure light source has begun to receive attention and actively develop related technologies, but the aforementioned for manufacturing protection The nitrocellulose material of the film absorbs a light source having a wavelength of less than 350 nm, and the fluorinated polymer absorbs a wavelength of less than 190 nm, so that a lithography process in which the wavelength of the light source is lower than 350 nm or 190 nm cannot be used.

Since the ruthenium crystal film is light for EUV, the light absorption coefficient is relatively low, especially the polycrystalline ruthenium film, which has a lower absorption coefficient than the amorphous ruthenium film or the single crystal ruthenium film, so that it can easily satisfy the EUV. The light transmittance required for the protective film; in particular, the above-mentioned protective film for EUV using a ruthenium crystal film, there is still a problem that the ruthenium crystal film is not easily formed in the technique of ruthenium crystal film formation, and the published US Patent 6,623,893 A protective film made of tantalum material is proposed, which is formed by a chemical vapor deposition (CVD) technique on a gate layer made of a tantalum material such as hafnium oxide. The barrier layer is formed by removing the screen layer by an etching process, but the central portion of the protective film is exposed, but the process is complicated.

Further, in the disclosed Chinese patent CN 101414118 A, a reticle protective film made of a single crystal ruthenium film and a method for producing the same are disclosed, which are produced by thinning an SOI substrate, specifically, thinning. A main surface of the SOI substrate forms a protective film of a single crystal germanium, and in the subsequent process, the SOI substrate is removed by an etching technique to expose the central portion of the single crystal germanium. Become a protective film.

In the disclosed Taiwan patent "Pneumatic film assembly for EUV" (Publication No. 201415157), a dust-proof film assembly for EUV which can reduce the reduction of incident EUV light and has high strength is proposed. Wherein the EUV pellicle is assembled through an EUV permeable film (which is a twin film) reinforced with an auxiliary structure of a mesh shape (for example, a honeycomb structure), but the auxiliary structure and the twin film are not firmly adhered thereto. During the exposure process, the separation of the auxiliary structure from the twin film is caused, which causes damage to the twin film.

Regardless of the exposure of the illuminant protection film assembly, the material of the protective film must have appropriate uniformity, mechanical strength, penetration, and cleanliness to withstand the continual exposure of the reticle pattern to the wafer. Shadow processing, and overcoming the problem of contamination during storage and transportation or damage to the reticle protective film; in addition, the approved invention patent TW I398723 "Protective film assembly and its manufacturing method" has proposed a single crystal film. The pellicle film of the pellicle film comprises an inorganic protective film formed on at least one side of the pellicle film, but since the inorganic protective film is liable to be broken due to movement, how to avoid this situation will be the focus of the present invention.

Therefore, if a tantalum nitride layer can be separately deposited on both surfaces of an inorganic protective film (graphene layer), the tantalum nitride layer can be used to sandwich the graphene layer and protect the graphene layer. In order to increase the structural strength of the graphene layer, it is possible to avoid cracking of the graphene layer during the movement, so the present invention should be an optimum solution.

The invention relates to a method for manufacturing an EUV mask inorganic protective film module, which is capable of depositing a tantalum nitride layer on two surfaces of a graphene layer, and the tantalum nitride layer can be used for clamping The graphene layer is held and used to protect the graphene layer to increase the structural strength of the graphene layer.

The invention relates to a method for manufacturing an EUV mask inorganic protective film assembly, which comprises: taking a copper foil with a flat surface, and covering the top surface of a small frame with a copper foil surface area larger than a top surface of the small frame body And inserting a large frame into the outer surface of the small frame, so that the edge of the copper foil is clamped by the large and small frame; the size frame with the copper foil is placed on a base, and placed In a quartz glass tube, it is heated to 1000 ° C or higher and methane is applied to form a graphene layer on the surface of the copper foil; the large and small frames sandwiching the copper foil and the graphene layer are taken out and the surface of the graphene layer is removed. Depositing a first tantalum nitride layer by a chemical vapor deposition method; forming a perfluoropolymer layer on the surface of the first tantalum nitride layer by spin coating or spraying; and organically coating the surface of the perfluoropolymer layer The colloid adheres to a temporary frame; the copper foil is eluted by a ferric chloride lotion to dissolve the copper foil; and the second surface of the graphene layer is deposited by chemical vapor deposition. a tantalum nitride layer for receiving the graphene layer from the first tantalum nitride layer And clamping the second tantalum nitride layer; on the other surface of the second layer of tantalum nitride layer, a main frame body is adhered by an inorganic colloid; the temporary frame body is removed, and a perfluorocarbon is simultaneously removed The solvent removes the perfluoropolymer layer to form an EUV reticle inorganic protective film module.

More specifically, the first tantalum nitride layer serves to support the graphene layer to prevent cracking of the graphene layer due to movement.

More specifically, when the copper foil is eluted by the ferric chloride lotion, since the perfluoropolymer layer and the graphene layer are both polymer materials, they are not subjected to the iron chloride lotion. Erosion to protect the first tantalum nitride layer from dissolution.

More specifically, the first tantalum nitride layer and the second tantalum nitride layer sandwich the graphene layer to protect the graphene layer and simultaneously increase the structural strength of the graphene layer.

More specifically, the EUV photomask inorganic protective film assembly is irradiated with extreme ultraviolet light having a wavelength of 13.5 nm, and the thickness of the first tantalum nitride layer is 5 nm when the thickness of the graphene layer is 8 nm. The second tantalum nitride layer has a thickness of 5 nm and a light transmittance of 90%.

More specifically, the EUV mask inorganic protective film assembly is irradiated with extreme ultraviolet light having a wavelength of 13.5 nm, and the thickness of the first tantalum nitride layer is 5 nm when the thickness of the graphene layer is 25 nm. The second tantalum nitride layer has a thickness of 5 nm and a light transmittance of 80%.

More specifically, the first tantalum nitride layer and the second tantalum nitride layer can be replaced by a first base metal layer and a second base metal layer, and the thickness of the first base metal and the second base metal is 5nm.

1‧‧‧ copper foil

11‧‧‧graphene layer

12‧‧‧First tantalum layer

13‧‧‧Perfluoropolymer layer

14‧‧‧Second tantalum layer

2‧‧‧Small frame

3‧‧‧ large frame

4‧‧‧Base

5‧‧‧Quartz glass tube

6‧‧‧ Temporary frame

7‧‧‧Main frame

[Fig. 1] is a schematic flow chart showing a method of manufacturing an EUV photomask inorganic protective film module of the present invention.

[Fig. 2A] is a schematic view showing the arrangement of copper foil of the method for producing an EUV photomask inorganic protective film module of the present invention.

[Fig. 2B] is a schematic view showing the arrangement of copper foil of the method for producing an EUV photomask inorganic protective film module of the present invention.

[Fig. 3] Fig. 3 is a schematic diagram showing the graphene layer and formation of the method for producing an EUV mask inorganic protective film module of the present invention.

[Fig. 4] is a schematic view showing the deposition of the first tantalum nitride layer of the EUV mask inorganic protective film module manufacturing method of the present invention and a temporary frame.

[Fig. 5] Fig. 5 is a schematic view showing the formation of a perfluoropolymer layer of the method for producing an EUV photomask inorganic protective film module of the present invention.

[Fig. 6] Fig. 6 is a schematic view showing dissolution of a copper foil of the method for producing an EUV photomask inorganic protective film module of the present invention.

[Fig. 7] is a schematic view showing deposition of a second tantalum nitride layer in the method for producing an EUV photomask inorganic protective film module of the present invention.

[Fig. 8] Fig. 8 is a schematic view showing the main frame of the manufacturing method of the EUV photomask inorganic protective film module of the present invention.

[Fig. 9] is a schematic view showing the removal of the temporary frame and the perfluoropolymer layer in the method for producing the EUV photomask inorganic protective film module of the present invention.

Other details, features, and advantages of the present invention will be apparent from the following description of the preferred embodiments.

Please refer to FIG. 1 , which is a schematic diagram of a decoding and identification process of a method for manufacturing an EUV photomask inorganic protective film module according to the present invention. The method can be seen as follows: taking a copper foil with a flat surface and covering the copper foil with a small one. The top surface of the frame has a surface area larger than the top surface of the small frame, and a large frame is nested on the outer surface of the small frame, so that the edge of the copper foil is sandwiched by the large and small frames. The size frame with the copper foil is placed on a base, placed in a quartz glass tube and heated to above 1000 ° C and passed through methane to form a layer of graphene 102 on the surface of the copper foil; a large and small frame of the copper foil and the graphene layer, and depositing a first tantalum nitride layer 103 on the surface of the graphene layer by a chemical vapor deposition method; using spin coating on the surface of the first tantalum nitride layer Or spraying method to form a perfluoropolymer layer 104; Adhesively adhering a temporary frame 105 to the surface of the perfluoropolymer layer via an organic colloid; the copper foil is washed by a ferric chloride lotion to dissolve the copper foil 106; and the graphene layer is another Depositing a second tantalum nitride layer on the surface by chemical vapor deposition to sandwich the graphene layer from the first tantalum nitride layer and the second tantalum nitride layer; On the other surface of the ruthenium layer, a main frame 108 is adhered by an inorganic colloid; the temporary frame is removed, and the perfluoropolymer layer is removed by a perfluoro solvent to form an EUV. Photomask inorganic protective film assembly 109.

Please refer to FIGS. 2A and 2B , which are schematic diagrams showing the copper foil of the method for manufacturing the EUV photomask inorganic protective film module of the present invention. As can be seen from the figure, a copper foil 1 having a flat surface is first taken, and the copper foil 1 is covered by a copper foil 1 . The top surface of the small frame 2, the surface area of the copper foil 1 is larger than the top surface of the small frame 2, and then the large frame 3 is placed on the outer surface of the small frame 2, so that the edge of the copper foil 1 is subjected to The clamping of the large frame 3 and the small frame 2; please refer to FIG. 3, which is a schematic view showing the formation of a graphene layer in the method for manufacturing the EUV photomask inorganic protective film module of the present invention. The large frame 3 and the small frame 2 of the foil 1 are placed on a base 4, and placed in a quartz glass tube 5 to be heated to 1000 ° C or higher and methane is passed through to form a graphene layer 11 on the surface of the copper foil 1. (Graphene); please refer to FIGS. 4~5, which are schematic diagrams showing the deposition of the first tantalum nitride layer and the formation of the perfluoropolymer layer in the method for manufacturing the EUV mask inorganic protective film module of the present invention, which can be seen from the figure Taking out the large frame 3 and the small frame 2 on the copper foil 1 and the graphene layer 11 and the graphene 11 surface depositing a first tantalum nitride layer 12 via chemical vapor deposition (CVD) to support the graphene layer to avoid cracking of the graphene layer due to movement (see FIG. 2); A perfluoropolymer layer 13 is formed on the surface of the tantalum nitride layer 12 by spin coating or spray coating. Perfluoro polymer, and then, as shown in FIG. 4, a temporary frame 6 is adhered to the surface of the perfluoropolymer layer 13 via an organic colloid, and then, as shown in FIG. 5, the large frame 3 is further The small frame 2 is separated from the copper foil 1 and the graphene layer 11; please refer to FIG. 6 , which is a schematic diagram of the dissolution of the copper foil of the EUV mask inorganic protective film module manufacturing method and a temporary frame arrangement diagram thereof. It can be seen that the copper foil 1 can be dissolved by the ferric chloride detergent to dissolve and disappear the copper foil 1. Since the perfluoropolymer layer 13 and the graphene layer 11 are both polymer materials, they are not subjected to chlorine. Corrosion of iron-iron lotion to protect the first tantalum nitride layer 12; see Figures 7-8, is a schematic diagram of the second tantalum nitride layer deposition method of the EUV mask inorganic protective film module manufacturing method of the present invention A schematic diagram of the frame arrangement, as shown in the figure, a second tantalum nitride layer 14 is deposited on the other surface of the graphene layer 11 by chemical vapor deposition (CVD) to subject the graphene layer 11 to the first tantalum nitride layer. The layer 12 and the second tantalum nitride layer 14 are sandwiched to protect the graphene layer 11 and simultaneously increase the graphene The structural strength of the layer 11, and then, as shown in Fig. 8, another main surface of the second layer of the tantalum nitride layer 14 is adhered via an inorganic colloid 7; see Fig. 9, which is the EUV of the present invention. Schematic diagram of the removal of the temporary frame and the perfluoropolymer layer in the method for manufacturing the reticle inorganic protective film module. As can be seen from the figure, the temporary frame 6 can be removed, and then the perfluoropolymer is polymerized in a perfluoro solvent. The layer 13 is removed to form an EUV reticle inorganic protective film assembly.

And the EUV mask inorganic protective film assembly formed by the above manufacturing step has a thickness of 8 nm of the graphene layer 11 under the irradiation of extreme ultraviolet light (EUV) having a wavelength of 13.5 nm, and the first tantalum nitride layer and The second tantalum nitride layer has a thickness of 5 nm and a light transmittance of 90%.

Further, if the graphene layer 11 has a thickness of 25 nm, the first tantalum nitride layer and the second tantalum nitride layer have a thickness of 5 nm when irradiated with extreme ultraviolet light (EUV) having a wavelength of 13.5 nm, and the light transmittance thereof is 5 nm. It is 80%.

The method for manufacturing the EUV reticle inorganic protective film module provided by the present invention has the following advantages when compared with other conventional techniques: the present invention can deposit a nitriding on both surfaces of an inorganic protective film (graphene layer). In the ruthenium layer, the ruthenium nitride layer can be used to sandwich the graphene layer and to protect the graphene layer to increase the structural strength of the graphene layer, thereby preventing cracking of the graphene layer during movement.

The present invention has been disclosed in the above embodiments, and is not intended to limit the present invention. Any of those skilled in the art can understand the foregoing technical features and embodiments of the present invention without departing from the invention. In the spirit and scope, the scope of patent protection of the present invention is subject to the definition of the claims attached to the present specification.

Claims (9)

The invention relates to a method for manufacturing an EUV mask inorganic protective film assembly, which comprises: taking a copper foil with a flat surface, and covering the top surface of a small frame with a copper foil surface area larger than a top surface of the small frame body And inserting a large frame into the outer surface of the small frame, so that the edge of the copper foil is clamped by the large and small frame; the size frame with the copper foil is placed on a base, and placed After heating into a quartz glass tube to a set temperature value, methane is applied to form a graphene layer on the surface of the copper foil; a large and small frame holding the copper foil and the graphene layer is taken out, and the graphene layer is removed. Depositing a first tantalum nitride layer by a chemical vapor deposition method; forming a perfluoropolymer layer on the surface of the first tantalum nitride layer by spin coating or spraying; forming a surface of the perfluoropolymer layer via the surface The organic colloid adheres to a temporary frame; the copper foil is eluted by a ferric chloride lotion to dissolve the copper foil; and the other surface of the graphene layer is deposited by chemical vapor deposition a layer of tantalum nitride for subjecting the graphene layer to the first nitridation The layer and the second tantalum nitride layer are sandwiched; on the other surface of the second layer of tantalum nitride layer, a main frame body is adhered by an inorganic colloid; the temporary frame body is removed, and at the same time The fluorosolvent removes the perfluoropolymer layer to form an EUV reticle inorganic protective film component. The method for producing an EUV mask inorganic protective film module according to claim 1, wherein the quartz glass tube has a heating temperature of 1000 ° C or higher. The method for manufacturing an EUV mask inorganic protective film assembly according to claim 1, wherein the first tantalum nitride layer is used to support the graphene layer to prevent the graphene layer from being broken due to movement. The method for manufacturing an EUV reticle inorganic protective film assembly according to claim 1, wherein When the copper foil is eluted by the ferric chloride lotion, since the perfluoropolymer layer and the graphene layer are both polymer materials, they are not corroded by the ferric chloride lotion, and are used to protect the first The tantalum nitride layer does not disappear by dissolution. The method for manufacturing an EUV mask inorganic protective film module according to claim 1, wherein the first tantalum nitride layer and the second tantalum nitride layer sandwich the graphene layer to protect the graphene layer and simultaneously increase The structural strength of the graphene layer. The method for manufacturing an EUV mask inorganic protective film module according to claim 1, wherein the EUV mask inorganic protective film assembly has a thickness of 8 nm in the graphene layer after being irradiated with extreme ultraviolet light having a wavelength of 13.5 nm. The thickness of the tantalum nitride layer was 5 nm, and the thickness of the second tantalum nitride layer was 5 nm, and the light transmittance was 90%. The method for manufacturing an EUV mask inorganic protective film module according to claim 1, wherein the EUV mask inorganic protective film assembly has a thickness of 25 nm in the graphene layer after being irradiated with extreme ultraviolet light having a wavelength of 13.5 nm. The thickness of the tantalum nitride layer was 5 nm, and the thickness of the second tantalum nitride layer was 5 nm, and the light transmittance was 80%. The method for manufacturing an EUV mask inorganic protective film assembly according to claim 1, wherein the first tantalum nitride layer and the second tantalum nitride layer can be replaced by a first tantalum metal layer and a second tantalum metal layer. The method for manufacturing an EUV mask inorganic protective film module according to claim 8, wherein the first base metal layer and the second base metal layer have a thickness of 5 nm.