JP5754592B2 - Reflective mask manufacturing method and reflective mask - Google Patents

Description

  The present invention relates to a reflective mask manufacturing method and a reflective mask. More specifically, the present invention relates to a semiconductor manufacturing apparatus using EUV lithography that uses extreme ultraviolet (EUV: Extreme Ultra Violet) as a light source. The present invention relates to a reflective mask manufacturing method and a reflective mask.

(Description of EUV lithography)
In recent years, with the miniaturization of semiconductor devices, EUV lithography using EUV having a wavelength of around 13.5 nm as a light source has been proposed. Since EUV lithography has a short light source wavelength and very high light absorption, it needs to be performed in a vacuum. In the EUV wavelength region, the refractive index of most substances is slightly smaller than 1. For this reason, the EUV lithography cannot use a transmission type refractive optical system which has been used conventionally, and becomes a reflection optical system. Accordingly, a conventional transmissive photomask cannot be used as the original photomask, so it is necessary to use a reflective photomask (hereinafter referred to as a reflective mask).

(Description of the structure of the reflective mask and mask blanks)
Such a reflective mask is produced based on a substrate called a mask blank. On the surface of this substrate, a multilayer reflective layer showing a high reflectance with respect to the exposure light source wavelength and an absorption layer of the exposure light source wavelength are sequentially formed on the low thermal expansion substrate. In general, a back surface conductive film for fixing an electrostatic chuck in the exposure machine is formed on the back surface of the substrate. Some have a structure having a buffer layer between the multilayer reflective layer and the absorbing layer.

  When processing from a mask blank to a reflective mask, the absorbing layer is partially removed by electron beam (EB) lithography and etching technology, and in the case of a structure having a buffer layer, the absorbing layer is also removed. A circuit pattern consisting of parts is formed. The light image reflected by the reflection type mask thus created is transferred onto the semiconductor substrate via the reflection optical system.

(Explanation of film thickness and reflectance of the absorption layer of the reflective mask)
In the exposure method using the reflective optical system, irradiation is performed at an incident angle (usually 6 °) inclined by a predetermined angle from the vertical direction with respect to the reflective mask surface. Occurs. Since the reflection intensity in the shadowed portion is smaller than that in the non-shadowed portion, the contrast is lowered, and the edge portion of the transfer pattern may be blurred or deviated from the design dimension. Such a phenomenon is called shadowing and is one of the fundamental problems of the reflective mask.

  In order to prevent such blurring of the pattern edge portion and deviation from the design dimension, it is effective to reduce the thickness of the absorption layer and reduce the height of the pattern. However, when the thickness of the absorbing layer is reduced, the light shielding property in the absorbing layer is lowered, the transfer contrast is lowered, and the accuracy of the transfer pattern is lowered. That is, if the absorption layer is made too thin, the contrast necessary for maintaining the accuracy of the transfer pattern cannot be obtained.

  As described above, since the thickness of the absorption layer is too thick or too thin, it is currently in the range of about 50 to 90 nm, and the reflectance of the EUV light at the absorption layer is 0. It is about 5 to 2%.

(Explanation of multiple exposure of adjacent chips)
On the other hand, when a transfer circuit pattern is formed on a semiconductor substrate such as a silicon wafer using a reflective mask, chips having a plurality of circuit patterns are formed on one semiconductor substrate. There may be a region where the outer periphery of the chip overlaps between the adjacent chips. This is because the chips are arranged at a high density in order to improve productivity to increase the number of chips that can be taken per wafer.

  In this case, the region where the chip outer peripheral portions overlap is exposed (multiple exposure) a plurality of times (up to four times). The chip outer peripheral portion of this transfer pattern is also the outer peripheral portion on the reflective mask, and is usually the absorption layer portion. However, as described above, since the reflectance of EUV light on the absorption layer is about 0.5 to 2%, there is a problem that the outer periphery of the chip is exposed by multiple exposure. For this reason, the chip outer peripheral portion on the mask is required to be a low-reflectance region (hereinafter referred to as a light-shielding frame) where the EUV light shielding property is higher than that of a normal absorption layer and the reflectance is 0.3% or less. Sex came out.

  In order to solve such problems, the reflection of the multilayer reflective layer can be achieved by forming a groove dug from the absorption layer of the reflective mask to the multilayer reflective layer, or by laser irradiation or ion implantation on the reflective mask. A reflective mask provided with a light-shielding frame having a high light-shielding property with respect to the exposure light source wavelength by reducing the rate has been proposed. (For example, see Patent Document 1)

(Explanation of out-of-band effects)
In addition, in multiple exposure, not only exposure with EUV light but also out-of-band light (hereinafter referred to as OoB light (OoB: Out of Band)) to a near infrared region from a vacuum ultraviolet region other than the 13.5 nm band. Similarly, there is a problem that the outer periphery of the chip is exposed to light. The OoB light is reflected by the EUV absorption layer of the mask (a material containing tantalum (Ta) is often used as the main material) and emitted to the wafer. For this reason, light having various wavelengths other than 13.5 nm is irradiated on the resist on the wafer and exposed to light, which has an adverse effect on the pattern size in the vicinity of the chip boundary region.

JP 2009-212220 A

  However, in the method of the above-mentioned patent document, it is necessary to process a total of 80 layers of molybdenum (Mo) and silicon (Si) of different materials when digging the multilayer reflective layer in the area of the light shielding frame after creating the mask pattern. However, it was a very complicated condition to realize in dry etching. In addition to the etching of the main pattern, it is necessary to perform lithography and etching in two steps, which disadvantageously deteriorates throughput.

  Further, even when the light shielding frame is formed by digging and removing all of the absorption layer and the multilayer reflective layer to expose the substrate surface by the method of the above-mentioned patent document, a conductive film is provided on the back surface of the substrate. The conductive film is often made of a material containing chromium (Cr) as the main material, and OoB light entering from the mask surface is transmitted through the substrate, reflected by the conductive film on the back surface, and transmitted through the substrate again. There is an inconvenience of adversely affecting the mask surface.

  An object of the present invention is to provide a manufacturing method of a reflective mask and a reflective mask that have a light-shielding frame that reduces the influence of OoB light.

  The present invention employs the following methods and configurations in order to solve the above problems.

  The present invention relates to a method of manufacturing a reflective mask used in extreme ultraviolet (EUV) lithography. A step of forming a light reflecting layer on one surface of the substrate; a step of forming a light absorbing layer on the light reflecting layer; a step of forming a conductive film on the other surface of the substrate; and a circuit on the light reflecting layer. A step of forming a pattern, a step of forming a light-shielding frame formed by removing the light reflecting layer and the light absorbing layer in the frame-shaped region outside the circuit pattern until one surface of the substrate is exposed, and a conductive film in the frame-shaped region And a step of forming a conductive film removal region that is removed until the other surface of the substrate is exposed.

  In addition, the substrate is transparent, and the light reflecting layer, the light absorbing layer, and the conductive film are irradiated with laser light from one side or the other side of the substrate to emit light. By removing the reflective layer, the light absorption layer, and the conductive film, the step of forming the light shielding frame and the step of forming the conductive film removal region are performed collectively.

  Further, the step of forming the light shielding frame and the step of forming the conductive film removal region are performed before the step of forming the circuit pattern.

  Further, the step of forming the light shielding frame and the step of forming the conductive film removal region are performed after the step of forming the circuit pattern.

Further, the laser light is characterized by using a laser light by a YAG laser or a CO ₂ laser.

  And this invention relates to the reflective mask used for EUV lithography, It was manufactured by the manufacturing method of the reflective mask in any one of said.

  According to the present invention, since it has the above-described features, the following can be achieved.

  That is, a method of manufacturing a reflective mask used in extreme ultraviolet (EUV) lithography, a step of forming a light reflecting layer on one surface of a substrate, and a step of forming a light absorbing layer on the light reflecting layer The one surface of the substrate exposes the step of forming a conductive film on the other surface of the substrate, the step of forming a circuit pattern on the light reflecting layer, and the light reflecting layer and the light absorbing layer in the frame region outside the circuit pattern. A step of forming a light-shielding frame formed by removing the conductive film in a frame-shaped region and a step of forming a conductive film removal region formed by removing the conductive film in the frame-shaped region until the other surface of the substrate is exposed. Reflecting by the conductive film on the other surface, passing through the substrate again, and returning to the mask surface, it is possible to reduce the adverse effect of OoB light.

  In addition, the substrate is transparent, and the light reflecting layer, the light absorbing layer, and the conductive film are irradiated with laser light from one side or the other side of the substrate to emit light. By removing the reflective layer, the light absorption layer, and the conductive film, the process of forming the light shielding frame and the process of forming the conductive film removal region are performed in a lump. Therefore, by dry etching or the like for forming the light shielding frame Throughput is higher than the digging technique. In addition, since the front and back surfaces can be simultaneously removed by the laser, the positional accuracy on the front and back surfaces of the mask can be increased, and the influence of OoB at the conductive film interface between the glass and the other surface can be reduced. By using this reflective mask, a transfer pattern can be formed with high accuracy.

  In addition, since the step of forming the light shielding frame and the step of forming the conductive film removal region are performed before the step of forming the circuit pattern, the circuit can be adjusted while adjusting to the already formed light shielding frame as necessary. A pattern can be formed.

  In addition, since the step of forming the light shielding frame and the step of forming the conductive film removal region are performed after the step of forming the circuit pattern, the light shielding frame is adjusted as necessary according to the already formed circuit pattern. Can be formed.

In addition, since laser light from a YAG laser or CO ₂ laser is used as the laser light, the multilayer reflective layer, the absorption layer, the conductive film, and the like can be reliably removed by the laser light having a short wavelength and high energy.

  Since the reflective mask used in EUV lithography is manufactured by any of the above-described reflective mask manufacturing methods, a highly accurate reflective mask can be obtained.

Schematic sectional view showing the structure of a reflective mask used in an embodiment of the present invention Schematic which shows the principal part of the reflective mask used for embodiment of this invention. Schematic sectional view showing the structure of a reflective mask used in an embodiment of the present invention Schematic which shows the principal part of the reflective mask used for embodiment of this invention. Schematic of a reflective mask in an embodiment of the present invention Schematic of a reflective mask in an embodiment of the present invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Configuration of reflective mask before circuit pattern formation)
First, the configuration of a reflective mask before forming a circuit pattern will be described with reference to FIGS. 1A to 1D are schematic cross-sectional views of a substantially central portion of a reflective mask 100, 200, 300, 400 that is an embodiment of the present invention. 2A is a schematic view of the reflective masks 100, 200, 300, and 400 shown in FIGS. 1A to 1D as viewed from one side, and FIG. FIG. 2C is a schematic view of the reflective masks 300 and 400 viewed from the other surface side. In the following description, the surface of the reflective mask 100, 200, 300, 400 on which the circuit pattern of the substrate 11 is formed is referred to as one surface, and the opposite surface is referred to as the other surface.

In the reflective mask 100 shown in FIG. 1A, a multilayer reflective layer (light reflective layer) 21 is formed on one surface of a substrate 11, and an absorbing layer (light absorbing layer) 51 is formed on the multilayer reflective layer 21. The conductive film 71 is formed on the other surface of the substrate 11.
The reflective mask 200 shown in FIG. 1B has a configuration in which a buffer layer 41 is added between the multilayer reflective layer 21 and the absorption layer 51 of the reflective mask 100, and the multilayer reflective layer is formed on one surface of the substrate 11. 21, the buffer layer 41, and the absorption layer 51 are formed in order. A conductive film 71 is formed on the other surface of the substrate 11.
The reflective masks 300 and 400 shown in FIGS. 1C and 1D are formed such that the conductive film 71 is removed from the other surface of the reflective masks 100 and 200.

  As shown in FIG. 2A, an absorption layer region 80 and a frame-shaped frame region 90 are formed on one surface of the reflective masks 100, 200, 300, and 400. In the frame-shaped region 90, as shown in FIG. 1, the multilayer reflective layer 21 and the absorbing layer 51, or the multilayer reflective layer 21, the buffer layer 41, and the absorbing layer 51 are removed in a groove shape to form the light shielding frame 25. ing. At the bottom of the light shielding frame 25, one surface of the substrate 11 is exposed and exposed.

As shown in FIG. 2B, a conductive film 71 and a frame-shaped conductive film removal region 72 are formed on the other surface of the reflective masks 100 and 200. In the conductive film removal region 72, as shown in FIGS. 1A and 1B, the conductive film 71 in the frame-shaped region 90 is removed in a groove shape. At the bottom of the conductive film removal region 72, the other surface of the substrate 11 is exposed and exposed.
As shown in FIG. 2C, the conductive film 71 is not provided on the other surface of the reflective masks 300 and 400, and the entire other surface of the substrate 11 is exposed and exposed.

  A method of forming the light shielding frame 25 and the conductive film removal region 72 shown in FIGS. 1 and 2 will be described. In the present embodiment, high-energy laser light having a short wavelength by using a YAG laser (using a fourth harmonic of 664 nm of 1064 nm) is used. The laser light is transmitted through the substrate 11, but the multilayer reflective layer 21, the absorption layer 51, the buffer layer 41, and the conductive film 71 are impermeable.

  First, in FIG. 1A, the conductive film 71 is formed on the entire other surface of the substrate 11 of the reflective mask 100, and then the multilayer reflective layer 21 and the absorption layer 51 are formed on the entire one surface of the substrate 11. Next, laser light is irradiated to the range of the frame-shaped region 90 from the one surface side or the other surface side. Then, the multilayer reflective layer 21, the absorption layer 51, and the conductive film 71 are collectively removed, and the light shielding frame 25 and the conductive film removal region 72 are formed.

  In the case of the reflective masks 200, 300, and 400 in FIGS. 1B, 1C, and 1D, the multilayer reflective layer 21, the buffer layer 41, the absorbing layer 51, and the conductive film are similarly irradiated by laser light. 71, or the multilayer reflection layer 21 and the absorption layer 51, or the multilayer reflection layer 21, the buffer layer 41, and the absorption layer 51 are collectively removed, and the light shielding frame 25 and the conductive film removal region 72 or the light shielding frame 25 are formed. The

In the description of this embodiment, the light shielding frame 25 and the conductive film removal region 72 are formed before the circuit pattern is formed, but may be after the formation.
Further, a YAG laser is used as the laser beam, but a CO ₂ laser or the like may be used.

  As described above, in the reflective masks 100 and 200 shown in FIGS. 1A and 1B, the light shielding frame 25 has a groove shape, and one surface of the substrate 11 is exposed at the bottom, and the back side of the substrate is also electrically conductive. Since the film removal region 72 is provided and the other surface of the substrate 11 is exposed, the OoB light that has transmitted through the substrate from the bottom of the light shielding frame 25 is reflected by the conductive film on the other surface, and is transmitted through the substrate again. It does not return to the mask surface, and the influence of OoB light can be reduced.

  In the case of the reflective masks 300 and 400 shown in FIGS. 1C and 1D, the conductive film 71 is not provided on the other surface, and the entire other surface of the substrate 11 is exposed and exposed. Therefore, the OoB light transmitted through the substrate from the bottom of the light shielding frame 25 is not reflected by the conductive film on the other surface, transmitted through the substrate again, and returned to the mask surface. Can be reduced. In this case, the reflective masks 300 and 400 are fixed with a vacuum chuck or the like in an exposure machine (not shown).

  Further, since the multilayer reflection layer 21, the absorption layer 51, the conductive film 71, and the like are collectively removed by laser irradiation, and the light shielding frame 25 and the conductive film removal region 72 are formed, the throughput is higher than the method of dug by dry etching or the like. Is expensive. In addition, since the front and back of the substrate 11 can be simultaneously removed with a laser, the positional accuracy on the front and back is high, and the influence of OoB can be extremely reduced. For these reasons, when forming a transfer circuit pattern on a semiconductor substrate, the transfer pattern can be formed with high accuracy.

(Details of reflective mask configuration: multilayer reflective layer)
The multilayer reflective layer 21 shown in FIGS. 1A and 1C is designed to achieve a reflectivity of about 60% with respect to EUV light in the vicinity of 13.5 nm. The multilayer reflective layer 21 is a laminated film in which 40-50 pairs of molybdenum (Mo) and silicon (Si) are alternately laminated, and the uppermost layer is made of ruthenium (Ru). The layer adjacent to the Ru layer is a Si layer. The reason why Mo and Si are used is that the absorption (extinction coefficient) with respect to EUV light is small and the difference in refractive index between Mo and Si EUV light is large, so that the reflectance at the interface between Si and Mo is high. It is because it can be made high. The uppermost Ru of the multilayer reflective layer plays a role as a stopper in processing of the absorption layer and a protective layer against chemicals during mask cleaning.

  The multilayer reflective layer 21 in FIGS. 1B and 1D is designed to achieve a reflectivity of about 60% with respect to EUV light in the vicinity of 13.5 nm. The uppermost layer is composed of a Si layer. In this case, the uppermost Si of the multilayer reflective layer also plays the same role as Ru described above.

(Details of reflective mask configuration: buffer layer)
The buffer layer 41 in FIGS. 1B and 1D is provided to protect the Si layer, which is the uppermost layer of the multilayer reflective layer 21 adjacent to the buffer layer when the absorbing layer 51 is etched or the pattern is corrected. It is made of a nitrogen compound (CrN) of chromium (Cr).

(Details of reflective mask configuration: Absorbing layer)
The absorbing layer 51 in FIGS. 1A to 1D is made of a tantalum (Ta) nitrogen compound (TaN) having a high absorption rate with respect to EUV near 13.5 nm. As other materials, tantalum boron nitride (TaBN), tantalum silicon (TaSi), tantalum (Ta), and oxides thereof (TaBON, TaSiO, TaO) may be used.

  1A to 1D may be an absorption layer having a two-layer structure in which a low reflection layer having an antireflection function with respect to ultraviolet light having a wavelength of 190 to 260 nm is provided on the upper layer. . The low reflection layer is for increasing the contrast and improving the inspection property with respect to the inspection wavelength of the mask defect inspection machine.

(Details of reflective mask configuration: conductive film)
The conductive film 71 shown in FIGS. 1A and 1B is generally made of CrN, but may be any material made of a metal material as long as it has conductivity.

(Description of reflective mask with circuit pattern)
Next, a reflective mask with a circuit pattern in which a circuit pattern is formed on the above-described reflective mask will be described. 3A to 3D are schematic cross-sectional views of substantially central portions of the reflective masks 101, 201, 301, 401 with circuit patterns in which the circuit pattern 85 is formed on the reflective masks 100, 200, 300, 400. FIG. Show. FIG. 4A is a schematic view of the reflective masks 101, 201, 301, and 401 with circuit patterns as viewed from one side. 4B is a schematic view of the reflective masks 101 and 201 with circuit patterns as viewed from the other side, and FIG. 4C is a schematic view of the reflective masks 301 and 401 as viewed from the other side. .

  In either case, the circuit pattern 85 is formed by digging up the absorption layer 51 or the absorption layer 51 and the buffer layer 41 on the multilayer reflective layer 21 located inside the light shielding frame 25. In the case of this embodiment, since the light shielding frame 25 and the conductive film removal region 72 are already formed, by forming the circuit pattern 85, the frame-shaped region 90 having a sufficiently lower reflectance with respect to the EUV light than the absorption layer region. To obtain a reflective mask.

(Method of forming a circuit pattern)
Now, a method for forming the circuit pattern 85 will be described in detail.
In the case of the reflective mask 100 or 300 shown in FIGS. 1A and 1C, after forming a resist pattern by electron beam lithography, the absorption layer 51 is obtained from fluorocarbon plasma or chlorine plasma, and if necessary, both plasmas. Etch. Thereafter, resist peeling cleaning is performed to obtain a reflective mask 101 or 301 with a circuit pattern shown in FIGS. 3A and 3C in which a circuit pattern 85 is formed on the absorption layer 51.

In the case of the reflective mask 200 or 400 shown in FIGS. 1B and 1D, first, similarly, after forming a resist pattern by electron beam lithography, from fluorocarbon plasma or chlorine plasma, if necessary, from both plasmas. The absorption layer 51 is etched. Next, the buffer layer 41 is etched by chlorine plasma. Thereafter, resist peeling cleaning is performed to obtain a reflective mask 201 or 401 with a circuit pattern shown in FIGS. 3B and 3D in which a circuit pattern 85 is formed on the absorption layer 51 and the buffer layer 41.
In this way, a reflective mask 201 or 401 having a frame-like region whose reflectivity for EUV light is sufficiently smaller than that of the absorbing layer region is obtained.

  The reflective mask manufacturing method and the reflective mask of the present invention are not limited to the above-described embodiments, and various modifications can be made. As an example, in the above-described embodiment, the multilayer reflective layer 21 is formed directly on one surface of the substrate 11. In order to prevent charge-up during exposure between the substrate 11 and the multilayer reflective layer 21. A conductive film may be provided.

  In order to describe the present invention in more detail, examples are given below, but the present invention is not limited to these examples. In the above-described embodiment and the following examples, the process of forming the light shielding frame 25 and the process of forming the circuit pattern 85 are reversed.

(Example of mask blank manufacturing method)
Examples of the method for manufacturing a reflective mask according to the present invention will be described below. First, as shown in FIG. 5A, a substrate 111, which is a low thermal expansion glass substrate used in this example, was prepared. Next, as illustrated in FIG. 5B, a conductive film 171 for electrostatic chucking was formed on the other surface of the substrate 111 using a sputtering apparatus. As shown in FIG. 5C, 40 pairs of reflective layers of molybdenum (Mo) and silicon (Si) designed to have a reflectance of about 64% with respect to EUV light having a wavelength of 13.5 nm. 121 was laminated on the substrate 111. Subsequently, as shown in FIG. 5D, an absorption layer 151 made of TaN was formed on the reflective layer 121 by a sputtering apparatus. The film thickness of the absorption layer 151 at this time was 50 nm. Thus, a mask blank 202 used in the present invention was produced.

(Example of patterning on mask blanks)
The mask blank 202 shown in FIG. 5D manufactured in Example 1 is subjected to electron beam lithography, dry etching, and resist peeling cleaning to form a circuit pattern 185 in the absorption layer 151, whereby FIG. A reflective mask 203 shown in FIG. At this time, for electron beam lithography, a chemically amplified positive resist (manufactured by Fuji Film Electronics Materials, product number: FEP-171) is used, and a dose of 15 μC / second is obtained by a drawing machine (manufactured by JEOL, product number: JBX9000). After drawing in cm, a resist pattern was formed using a TMAH (tetramethylammonium hydroxide) 2.38% developer. Further, Cl ₂ inductively coupled plasma was applied to the etching of the absorption layer 151.

(Example of creation of light shielding frame and conductive film removal region)
The reflective mask 203 shown in FIG. 6A produced in Example 2 is irradiated from the one side with a quadruple laser beam (266 nm) of a YAG laser at a frequency of 2.5 kHz and an output of 18 A to obtain an absorption layer. 151, the multilayer reflective layer 121, and the conductive film 171 were removed at once. In this way, as shown in FIG. 6B, the reflection mask 201 having the light shielding frame 125 and the conductive film removal region 172 was completed.

  The reflectance of EUV light (wavelength: 13.5 nm) on the absorption layer side of the reflective mask 201 shown in FIG. 6B produced in Example 3 was measured. The results are shown in Table 1. The reflectance in the region other than the light shielding frame was 1.24%, whereas the reflectance in the frame-like region was 0.00%. Further, in order to investigate the influence of the OoB light, the reflectance at a wavelength in the near-infrared region from the vacuum ultraviolet ray was measured and found to be 0.00%.

  Using the reflective mask 201 shown in FIG. 6B produced in Example 3, exposure was performed using 13.5 nm EUV as a light source, and four adjacent chips were transferred onto the semiconductor substrate. In the adjacent chip, although a part of the region corresponding to the light shielding frame on the manufactured reflective mask was overlapped, the resist exposure in the region on the semiconductor substrate was not confirmed.

  The present invention makes it easy to manufacture a light shielding frame of a reflective mask used when forming a transfer circuit pattern on a semiconductor substrate such as a silicon wafer while reducing the influence of out-of-band light. Therefore, the present invention can be applied to a reflective mask manufacturing method.

11, 111 Substrate 21, 121 Multi-layer reflective layer 25, 125 Light-shielding frame 41 Buffer layer 51, 151 Absorbing layer 71, 171 Conductive film 72, 172 Conductive film removal area 80 Absorbing layer area 85, 185 Circuit pattern 90 Frame-shaped area 100, 200, 300, 400 Reflective mask 101, 201, 301, 401 Reflective mask with circuit pattern 202 Mask blanks

Claims (6)

A method of manufacturing a reflective mask used in extreme ultraviolet (EUV) lithography,
Forming a light reflecting layer on one surface of the substrate;
Forming a light absorbing layer on the light reflecting layer;
Forming a conductive film on the other surface of the substrate;
Forming a circuit pattern on the light reflecting layer;
Forming a light shielding frame formed by removing the light reflecting layer and the light absorbing layer in the frame-shaped region outside the circuit pattern until one surface of the substrate is exposed;
Forming a conductive film removal region formed by removing the conductive film in the frame-shaped region until the other surface of the substrate is exposed;
A method of manufacturing a reflective mask, comprising: The substrate is transparent, and the light reflecting layer, the light absorbing layer, and the conductive film are irradiated with laser light that is not transmissive from one side or the other side of the substrate. By removing the light reflection layer, the light absorption layer, and the conductive film,
2. The method of manufacturing a reflective mask according to claim 1, wherein the step of forming the light shielding frame and the step of forming the conductive film removal region are collectively performed. 3. The method of manufacturing a reflective mask according to claim 2, wherein the step of forming the light shielding frame and the step of forming the conductive film removal region are performed before the step of forming the circuit pattern. 3. The method of manufacturing a reflective mask according to claim 2, wherein the step of forming the light shielding frame and the step of forming the conductive film removal region are performed after the step of forming the circuit pattern. 3. The method of manufacturing a reflective mask according to claim ₂ , wherein a laser beam by a YAG laser or a CO2 laser is used as the laser beam. A reflective mask manufactured by the method for manufacturing a reflective mask according to claim 1.

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