JP4601941B2 - Method for manufacturing transfer mask for charged particle beam and transfer mask for charged particle beam - Google Patents

Description

  The present invention relates to a charged particle having a stencil mask structure in which a pattern to be transferred is formed on a conductive thin film layer (membrane) composed of an absorber for absorbing a charged particle beam or a scatterer for scattering a charged particle beam. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charged particle beam transfer mask manufacturing method and a charged particle beam transfer mask, and more particularly to a charged particle beam for low energy electron proximity projection lithography LEEPL (Low Energy Electron-Beam Proximity Projection Lithography). The present invention relates to an image transfer mask and a manufacturing method thereof.

  In recent years, there is a strong demand for higher integration of semiconductor device circuits, and the next generation lithography (NGL: Next Generation Lithography), which is currently used for mass production, is an electron beam or soft X-ray (EUV: Extremely Ultra). Research and development of lithography using violet or the like as a light source has been actively conducted.

As the light source using an electron beam, as shown in FIG. 9, an electron projection lithography EPL (Electron-Beam Projection Lithography) in which a mask image is reduced and projected onto a wafer using a high energy electron beam having an acceleration voltage of about 100 KV. ) Method and a LEEPL method that uses a low-energy electron beam with an acceleration voltage of about 2 KV as shown in FIG.
The EPL system differs from the electron beam scanning system in accordance with the PREVAIL (Proposition Exposure with Variable Axis Immersion Lenses) system (HCC Pfeiffer, Journal of Vaccum Science 19 gAol 19 technol. LR Herriott, Journal of Vaccum Science and Technology B15 p.2130 (1997)), but it is common to adopt a scatterer membrane as described later.
Journal of Vaccum Science and Technology B17 p. 2840 (1999) Journal of Vaccum Science and Technology B15 p. 2130 (1997) The LEEPL system is a low-speed electron beam proximity projection transfer system proposed by Utsumi (T. Utsumi, Journal of Vaccum Science and Technology B17 p. 2897 (1999)). Journal of Vaccum Science and Technology B17 p. 2897 (1999)

In the EPL method, the circuit pattern is arranged on a large number of divided small areas (hereinafter referred to as subfields) on the mask, and a 1 mm × 1 mm square electron beam is irradiated to transfer the subfields at one time. It scans in the direction and transfers.
In the LEEPL system, the electron beam is raster-scanned and transferred to the entire transfer area of the mask.
In the case of the EPL method, as shown in FIG. 3, electrons that have passed through the opening 612 of the membrane 611 pass through the opening 641 of the aperture 640 and contribute to image formation, but electrons that have passed through the non-opening 613 of the membrane 611. Are scattered by the scatterer membrane, most of which cannot pass through the aperture 641 of the aperture 640 and do not contribute to image formation.
In the case of the LEEPL system, as shown in FIG. 4, scanning is performed while irradiating an electron beam 720 having a predetermined spot diameter with a gap G between the membrane 711 and the resist 780 being close to 30 μm to 90 μm. The electron beam irradiated to the part 713 is absorbed by the membrane 711 which is an absorber and does not contribute to image formation, and only the electron beam irradiated to the opening 712 of the membrane 711 contributes to image formation.

The mask used here is called a stencil mask. Conventionally, a thin membrane mainly made of silicon, diamond or the like is used as an electron beam absorbing layer or scattering layer, and a pattern is formed by punching it. Is.
Such a stencil mask is different in structure and material from a conventional photomask having a light-shielding layer of chromium or the like, and the manufacturing method is different, so that the conventional photomask manufacturing equipment cannot handle the manufacturing. There was a problem.

Further, as in the method shown in FIG. 7 described in Japanese Patent Laid-Open No. 2003-31480, when the pattern forming region of the base material is perforated, first, dry etching is performed to a predetermined thickness, and then wet etching is performed. A method of etching and penetrating the base material is also used, but this method is dry etching and wet etching, so the work is complicated, workability is poor, and it is not suitable for mass production .
Japanese Patent Laid-Open No. 2003-31480

As described above, the stencil mask is different in structure and material from the conventional photomask having a light shielding layer made of chromium or the like, and the manufacturing method is different. However, it was not possible to cope with the production, and this was required.
The present invention is corresponding to this, and the pattern to be transferred is formed on the conductive thin film layer (membrane) made of the absorber for absorbing the charged particle beam or the scatterer for scattering the charged particle beam. The transfer mask for charged particle beam with the stencil mask structure can be used as much as possible with conventional photomask manufacturing equipment for light transfer using chrome or the like as a light-shielding film. An object of the present invention is to provide a transfer mask for charged particle beam and a manufacturing method thereof.

The method for producing a transfer mask for charged particle beam according to the present invention comprises a pattern to be transferred to a conductive thin film layer (membrane) comprising an absorber for absorbing charged particle beam or a scatterer for scattering charged particle beam. A charged particle beam transfer mask manufacturing method for producing a charged particle beam transfer mask having a stencil mask structure with openings formed therein, in which (a) a charged particle beam is absorbed on one surface of a plate-like substrate in order A thin film layer forming step of disposing a conductive thin film layer comprising an absorber for scattering or a scatterer for scattering charged particle beams, and (b) pattern formation of the substrate from the side of the substrate other than the thin film layer side (C) a transfer pattern forming step of forming a pattern to be transferred to the thin film layer by dry etching or wet etching the thin film layer; The thin portion of the substrate that Tsu, was removed by wet etching, to penetrate the base material of the formation region of the pattern, and, a wet etching process to leave a thin film layer formed of a pattern, which carries out, The plate-like substrate is a glass substrate for a photomask .
Alternatively, the method for producing a transfer mask for charged particle beam according to the present invention transfers the transfer to a conductive thin film layer (membrane) comprising an absorber for absorbing the charged particle beam or a scatterer for scattering the charged particle beam. A charged particle beam transfer mask manufacturing method for producing a charged particle beam transfer mask having a stencil mask structure in which an opening pattern is to be formed, which is not (a1) a plate-like base material on the thin film layer forming side in order A thin film is formed by machining a pattern forming region, and (b1) an electroconductive thin film layer comprising an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams, A thin film layer disposing step disposed on one surface of the substrate not on the machining side; and (c1) a transfer for forming a pattern to be transferred to the thin film layer by dry etching or wet etching of the thin film layer. And (d1) a wet forming process in which a thin portion of the substrate remaining in the thin wall is removed by wet etching to penetrate the substrate in the pattern formation region and leave the thin film layer on which the pattern is formed. An etching step is performed , and the plate-like base material is a glass substrate for a photomask .
And in the method for producing a transfer mask for charged particle beam according to any one of the above, the plate-like base material is not a conductive material (such as glass), and after the wet etching step, A conductive layer disposing step of disposing the conductive layer from the surface (back surface) side that is not the surface on the thin film layer forming side is performed.
When using a conductive material (ceramic, low expansion metal, etc.) as a plate-shaped substrate, it is necessary to dispose the conductive layer from the surface (back surface) side that is not the surface on the thin film layer forming side of the substrate. Absent.
Examples of the conductive ceramic include ZPF manufactured by Nippon Ceratech Co., Ltd.
In addition, in any one of the above-described methods for manufacturing a charged particle beam transfer mask, at least one of a cleaning step, an inspection step, and a correction step is performed as necessary after the transfer pattern forming step and before the wet etching step. It is characterized by this.
Also, in any one of the above-described methods for manufacturing a charged particle beam transfer mask, the machining is performed using any one of cutting processing such as milling and sand blasting.
As an apparatus which performs cutting, NC processing machines, such as a machining center and an end mill, are mentioned.
A method of manufacturing a transfer mask for charged particle beam according to any one of the above, and a method for manufacturing a transfer mask for charged particle beam for low-energy electron proximity projection lithography LEEPL (Low Energy Electron-Beam Proximity Projection Lithography). It is characterized by.
Also, in any one of the above methods for producing a charged particle beam transfer mask, the base material is a photomask substrate such as quartz glass (synthetic quartz) or low expansion glass.
Also, in any one of the above methods for producing a charged particle beam transfer mask, the thin film layer is a Cr single layer or a multilayer having a Cr layer as a main layer.

Here, as the plate-like substrate, the flatness on the side of the thin film layer formation (herein also referred to as the surface) is good at least from the warp and flatness of the thin film layer, and an exposure machine (electron beam drawing) Since the charged particle beam transfer mask is set on the surface (also referred to herein as the back surface) that is not the thin film layer forming side, the back surface has the same flatness as the front surface. .
Quartz, metal, glass, ceramic, etc. can be used as the base material of the mask for electron beam exposure, and the mask is chucked inside the exposure machine to support the image so that no distortion occurs during exposure. It is necessary to have a possible strength, but it is necessary to have a strength that does not cause deflection and distortion on the mask surface.
When the wafer is chucked and used as a mask in the exposure apparatus, a position accuracy of nano units is required.
For this reason, although a thin thing is preferable from the surface of a process, the thickness of a base material cannot be made very thin and is about several hundred micrometers to 10 mm.
In the conventional photomask having a light shielding layer made of Cr or the like, both surfaces of the base material have an overall flatness of several μm or less. It is relatively easy to obtain a large number of photomasks having an overall thickness of 1 μm or less.
Further, in the above, “thin wall” means that it is thinner than the original thickness, but it is a thickness that does not affect the quality of the thin film layer, and is preferably as thin as possible in terms of work productivity.

The charged particle beam transfer mask of the present invention forms an opening to be transferred to a conductive thin film layer (membrane) comprising an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams. A charged particle beam transfer mask having a stencil mask structure, wherein a plate-like base material is a base material of a support base material that supports the thin film layer, and from the side that is not the thin film layer forming side of the plate-like base material, A pattern forming area portion to be transferred by a base material is formed by through-hole processing, and the base material is made of a glass substrate such as quartz glass (synthetic quartz) for photomasks or low expansion glass, and a conductive thin film layer ( The membrane is made of a conductive light shielding film material for a photomask.
The charged particle beam transfer mask is a charged particle beam transfer mask for low-energy electron proximity projection lithography LEEPL (Low Energy Electron-Beam Proximity Projection Lithography).
The charged particle beam transfer mask according to any one of the above, wherein the charged particle beam transfer mask is manufactured by the method for manufacturing a charged particle beam transfer mask according to any one of claims 1 to 7. It is a feature.

(Function)
The manufacturing method of the transfer mask for charged particle beams according to the present invention has such a configuration, so that an electroconductive thin film comprising an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams. A transfer mask for charged particle beam having a stencil mask structure in which a pattern to be transferred to a layer (membrane) is formed, and using a conventional photo transfer photomask manufacturing facility using Cr or the like as a light shielding layer, and It is possible to provide a method of manufacturing a transfer mask for charged particle beam that can be manufactured with high productivity and no problem in quality.
Specifically, in order, (a) a conductive thin film layer made of an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams is disposed on one surface of a plate-like substrate. A thin film layer forming step, and (b) a machining step in which the pattern forming region of the base material is thinly processed from the side that is not on the thin film layer side of the base material, and (c) dry etching or wet etching of the thin film layer. , A transfer pattern forming step for forming a pattern to be transferred to the thin film layer, and (d) removing the thin portion of the substrate remaining in the thin wall by wet etching, penetrating the substrate in the pattern formation region, And a wet etching step that leaves a thin film layer on which a pattern is formed. The plate-like base material is a glass substrate for a photomask , or in order (a1) a plate-like shape. Substrate, thin A pattern forming region that is not on the layer forming side is machined thinly, and a conductive process comprising (b1) an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams A thin film layer disposing step of disposing the thin film layer on one surface of the substrate not on the machining side; and (c1) a transfer pattern for forming a pattern to be transferred to the thin film layer by dry etching or wet etching. And (d1) wet etching that removes the thin portion of the thin base material by wet etching, penetrates the base material in the pattern formation region, and leaves the thin film layer on which the pattern is formed. This is achieved by the fact that the plate-like substrate is a glass substrate for a photomask .
In particular, when the plate-like substrate is not a conductive material (such as glass), a conductive layer is disposed from the surface (back surface) side that is not the surface on the thin film layer forming side of the substrate after the wet etching step. By performing the conductive layer disposing step, the mask can be prevented from being charged up.
When using a conductive material (ceramic, low expansion metal, etc.) as a plate- shaped substrate, it is necessary to dispose the conductive layer from the surface (back surface) side that is not the surface on the thin film layer forming side of the substrate. Absent.

After machining and after the transfer pattern forming step, the thin portion of the substrate that has been machined and remains thin functions as a support for the thin film layer in the pattern formation region, so it is necessary before the wet etching step. Accordingly, it is possible to perform one or more of a cleaning process, an inspection process, and a correction process.
Examples of the machining include cutting such as milling and sand blasting. In particular, NC processing machines such as a machining center and an end mill are used as an apparatus for performing the cutting.
As a cutting device such as a milling machine, a machine with good machining speed and controllability is preferable. Usually, the entire desired pattern forming region is mechanically machined by scanning a machining tooth.
Further, in the case of sandblasting, processing is performed by spraying abrasive grains from an injection port such as a nozzle. However, in terms of accuracy, a milling apparatus is currently preferred.
In particular, in the case of a charged particle beam transfer mask for low-speed electron beam proximity projection lithography LEEPL that performs a close projection by scanning on the mask with a low acceleration voltage and an electron beam as a predetermined spot, an electron beam The entire irradiation region, that is, the entire transfer pattern region, has a pattern-formed thin film layer and does not have a beam, and is easier to machine than a structure having a beam.
As the thin film layer, a thin film layer having good conductivity that does not charge up at the time of transfer is used.
Further, the base material is a plate having good flatness, and quartz glass (synthetic quartz), low expansion glass, metal, ceramic, etc. can be applied.
In particular, when the substrate is a substrate for a photomask with good flatness such as quartz glass (synthetic quartz), low expansion glass, etc., the flatness of the thin film layer forming surface (surface) is overall, It can be relatively easily set to about 1 μm in the conventional technology, and the flatness (flatness) of the surface (back surface) which is not on the thin film layer forming surface side is overall, which can be set to this level in the conventional technology. Therefore, by using such a base material, it is possible to improve the flatness of the thin film layer in the finished pattern formation region in accordance with the good flatness of the base material surface before processing from its production method. Yes.
By using such a base material, it is possible to accurately apply machining such as milling and sandblasting.
In addition, when the thin film layer is a Cr single layer or a multilayer composed mainly of a Cr layer, the thin film layer forming process, the thin film layer patterning process, the wet etching process after machining, and the conventional chromium etc. are shielded. This can be performed using a general-purpose manufacturing facility for a photomask as a film.
In addition, since such a photomask substrate is relatively easy to manufacture and easily available for general use, the method for manufacturing a transfer mask for charged particle beam according to the present invention is a manufacturing method suitable for mass production. I can say that.

In addition, the charged particle beam transfer mask of the present invention has such a configuration, so that a conductive thin film layer comprising an absorber for absorbing a charged particle beam or a scatterer for scattering a charged particle beam. Using the stencil mask structure of charged particle beam transfer mask with an opening for the pattern to be transferred to the membrane, using as much as possible the conventional photomask manufacturing facility for photomasks using Cr or the like as a light-shielding layer. It is possible to provide a charged particle beam transfer mask that can be manufactured with good mass productivity without any problems.
Specifically, glass substrates such as quartz glass (synthetic quartz) and low expansion glass that are used in conventional photomasks are used as base materials for supporting substrates that support thin film layers, and are conventionally used for photomasks. Because the conductive light shielding film material used is a conductive thin film layer (membrane) for transfer pattern formation, the production facilities of conventional photomasks for light transfer using Cr as a light shielding layer are used as much as possible. Further, it is possible to apply the method for manufacturing the transfer mask for charged particle beam according to the present invention described above.

As described above, the present invention provides a stencil in which a pattern to be transferred is formed on a conductive thin film layer (membrane) made of an absorber for absorbing a charged particle beam or a scatterer for scattering a charged particle beam. A charged particle beam transfer mask for charged particle beam with a mask structure can be manufactured with high productivity by using photomask manufacturing equipment that uses conventional chromium as a light-shielding film and phototransferring as much as possible. Transfer mask and manufacturing method thereof can be provided.
In particular, in the method for producing a transfer mask for charged particle beam according to the present invention, when forming a through hole in a substrate, a mechanical processing method is employed instead of a conventional chemical etching processing method. Time can be greatly reduced.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a process sectional view of a first example of an embodiment of a method for manufacturing a transfer mask for charged particle beam according to the present invention, and FIG. 2 is an embodiment of a method for manufacturing a transfer mask for charged particle beam according to the present invention. It is process sectional drawing of the 2nd example of an example.
FIG. 1D and FIG. 2E are examples of the charged particle beam transfer mask of the present invention.
1 and 2, 110 is a base material, 115 is a hole (also referred to as a recess), 116 is a thin portion, 117 is a through-hole (also referred to as an opening), 120 is a thin film layer, 121 is a pattern portion, and 125. Is an opening portion, 127 is a pattern region, 210 is a base material, 215 is a hole portion (also referred to as a recess), 216 is a thin wall portion, 217 is a through-hole portion (also referred to as an opening portion), 220 is a thin film layer, and 221 is a pattern portion. Reference numeral 225 denotes an opening, and 227 denotes a pattern region.

First, a first example of an embodiment of a method for manufacturing a transfer mask for charged particle beam according to the present invention will be described with reference to FIG.
The method for manufacturing a charged particle beam transfer mask of the first example has a stencil mask structure in which a pattern to be transferred is formed on a conductive thin film layer (membrane) made of an absorber for absorbing charged particle beams. This is a charged particle beam transfer mask manufacturing method for producing a charged particle beam transfer mask for low-speed electron beam proximity projection lithography LEEPL. As a substrate 110 for supporting a thin film layer for pattern formation, flatness is all over. After forming a thin film layer 120 made of a Cr single layer for pattern formation on one surface of the base material 110 using a base material made of quartz glass (synthetic quartz) for conventional photomasks of 1 μm or less in order, The substrate 110 is processed and a transfer pattern is formed.
Hereinafter, a first example will be described with reference to FIG.
First, a thin film layer 120 made of a conductive Cr single layer made of an absorber for absorbing an electron beam is disposed on one surface of a plate-like substrate 110 with good flatness. (Fig. 1 (a))
The thin film layer 120 is formed by sputtering or the like.
As in this example, in the production of a charged particle beam transfer mask for low-speed electron beam proximity projection lithography LEEPL, the thickness of the thin film layer 120 made of a Cr single layer is the transferability and quality in the case of the mask. From the viewpoint of workability and the like, those in the range of 30 nm to 300 nm are usually used. Also, as a conventional photomask substrate 110 having good flatness and supporting the thin film layer 120 for pattern formation, quartz glass (synthetic quartz) or low expansion glass is usually used, and flatness is good. Those are preferred.
Incidentally, the flatness of the conventional photomask substrate 110 can be obtained relatively easily with an overall thickness of about 1 μm.
The time required to form the through hole in the base material 110 varies depending on the thickness of the base material, and the thinner one can form the through hole in a short time. However, a general-purpose 6.35 mm thickness is required in terms of strength and quality. Here it is used.
Next, the pattern forming region (see FIG. 1D) of the substrate 110 is machined thinly from the side of the substrate 110 that is not on the thin film layer 120 side. (Fig. 1 (b))
The machining means is preferably one that has a high processing speed, is easy to control, and has good processing quality, and includes milling, but is not particularly limited thereto.
Here, with the NC controlled milling machine (for example, V22 manufactured by Makino Milling Mfg. Co., Ltd.), the pattern formation region of the substrate 110 (see FIG. 1D) from the side that is not on the thin film layer 120 side of the substrate 110, The teeth are scanned and machined to a thin wall.
The thickness of the thin portion 116 of the base material 110 is preferably a thickness that does not affect the quality by machining and is as thin as possible from the viewpoint of processing productivity.
The thickness of the thin portion 116 is preferably 0.5 mm or more from the viewpoint of strength, and is preferably 1.5 mm or less from the viewpoint of quality.

Next, after forming a resist pattern having a predetermined opening corresponding to the pattern to be formed on the thin film layer 120, the thin film layer 120 is dry etched or wet etched to form a pattern to be transferred to the thin film layer. The resist pattern is removed. (Fig. 1 (c))
Etching and the like of the resist pattern can be performed similarly to the pattern formation of the conventional photomask.
Patterning is performed using an electron beam exposure apparatus or the like.
The resist is not particularly limited as long as it has desired resolution and good processability.
Etching is performed using a gas or a liquid suitable for the material of the thin film layer 120.
For example, when the thin film layer 120 is Cr-based, a chlorine-based gas is used for dry etching, and a ceric ammonium nitrate solution is used for wet etching.

Next, after performing cleaning, inspection, correction, etc., if necessary, the thinned portion 116 of the remaining base material 110 is removed by wet etching and penetrates the base material in the pattern formation region. And leave the patterned thin film layer as it is. (Fig. 1 (d))
In this example, since the base material 110 that is not a conductive material made of quartz glass (synthetic quartz) is used, a surface that is not a surface on the thin film layer forming side of the base material (back surface) is formed by sputtering thereafter. A conductive layer such as Cr is disposed from the side.
In the state where the thin layer 116 of the base material 110 under the thin film layer 120 is completely removed by etching, the mask portion has no mechanical strength. Therefore, the process used in the conventional photomask for cleaning, inspection, and correction is the thin film layer. Is damaged and cannot be taken.
Etching is performed using an etching solution suitable for the material of the base material 119.
When the substrate 110 is quartz glass (synthetic glass) or low expansion glass, a fluorine-based liquid is used for wet etching.
In addition, in the through hole forming process of the base material 110, switching from mechanical processing to chemical etching in the middle is because the thin film layer 120 is weak against mechanical impact and easily damaged, and therefore processing after approaching the membrane state Is a process by a wet etching process with less impact, and the thin film layer 120 remains.
As described above, the thin portion 116 of the substrate 110 is wet etched to leave the thin film layer 120, but the etching selectivity of the thin film layer 120 to the thin portion 116 in the wet etching needs to be several tens or more. , Preferably several hundred or more.
As the thin film layer 120, an etching stopper layer that increases the selectivity may be provided on the base 110 side.
In this case, the main layer other than the etching stopper layer of the thin film layer 120 and the substrate 110 may of course be made of the same material.
In the etching, stirring may be performed in consideration of the degree as necessary.
In this manner, an electron beam transfer mask for low-speed electron beam proximity projection lithography LEEPL is manufactured.
The thin film layer 120 in the pattern formation region after processing is kept in a stretched state, and the same level as that of the substrate can be obtained even in terms of flatness.
Although the thin film layer 120 in the pattern formation region is in a stretched state after the processing is finished, the stress control is different from the adjustment of the thin film formation conditions (pressure, temperature, flow rate, etc.) and the main component of the film. This is performed by adding elements (N, C, O, B, P, etc.).
Further, the shape of the mask may be changed according to the convenience of the chuck for fixing the mask of the exposure machine when the outer shape is cut and used after the processing is completed.
Further, when the substrate is penetrated by wet etching alone, it usually takes 10 days or more to penetrate, but in this example, the machining time is about 60 minutes and the wet etching time is about 3 days. The productivity of processing is extremely superior compared to the case of wet etching alone.
Further, as described above, except for the machining process, almost all conventional facilities for manufacturing a photomask for light transfer using Cr or the like as a light shielding layer can be used.
If a wafer is used as a plate-like base material and it is made by dry etching (EPL mask is made by this method), it takes 5 to 6 hours. there is not.
In addition, when a wafer is used as a plate-shaped substrate and the wafer is fabricated by wet etching (LEEPLE mask is being fabricated by this method), it takes about 10 hours. However, when a wafer is used as a plate-shaped substrate, the photomask fabrication process (inspection process, cleaning process, and correction process) cannot be used, resulting in mask accuracy problems.

In the first example, a single layer of Cr is used as the thin film layer 120, but the thin film layer 120 is not limited to this as long as it has good conductivity.
For example, a multilayer having a Cr layer as a main layer, a Ta single layer or a multilayer having a Ta layer as a main layer may be used.
The first example is a method of manufacturing a transfer mask for low-speed electron beam proximity projection lithography LEEPL, but the present invention is not limited to this.
For example, an EPL transfer mask can be formed by the same process by changing the thickness of the thin film layer.

  As described above, the transfer mask for low-speed electron beam proximity projection lithography LEEPL manufactured by the first example is an example of the embodiment of the transfer mask for charged particle beam of the present invention. Instead of the description of the manufacturing method of the first example, the description is omitted here. The transfer mask for this low-speed electron beam proximity projection lithography LEEPL is made of a glass substrate such as quartz glass (synthetic quartz) or low expansion glass, which is used in conventional photomasks, and a base material for a supporting substrate that supports a thin film layer. By using the conductive light-shielding film material used for conventional photomasks as a conductive thin film layer (membrane) for transfer pattern formation, the manufacturing process is as described above except for the machining process. In most cases, a conventional facility for manufacturing a photomask for light transfer using Cr or the like as a light shielding layer can be used.

Next, a second example of the embodiment of the manufacturing method of the charged particle beam transfer mask of the present invention will be briefly described with reference to FIG.
As in the first example, the second example is a stencil mask structure for LEEPL in which a pattern to be transferred is formed in a conductive thin film layer (membrane) made of an absorber for absorbing charged particle beams. Quartz glass for conventional photomasks with good flatness (synthetic quartz) as a base material for supporting a thin film layer for pattern formation in a manufacturing method of charged particle beam transfer masks for producing charged particle beam transfer masks ), But the pattern forming region of the substrate 210 (FIG. 2A) without the thin film layer, which is not on the thin film layer forming side, was machined thinly (FIG. 2). (B)) After that, a conductive thin film layer 220 made of an absorber for absorbing an electron beam is disposed on one surface of the substrate 210 not on the machining side, and then the thin film layer is dry-etched or wet-etched. Thin A pattern to be transferred to the layer is formed (corresponding to the state of FIG. 1B in FIG. 2C). Thereafter, the pattern is formed in the thin film layer 220 in the same manner as in the first example. (FIG. 2D), and further, the thin portion 216 of the substrate 210 is wet-etched to manufacture an electron beam transfer mask for LEEPL. (Fig. 2 (e))
Also in this example, since the base material 110 that is not a conductive material made of quartz glass (synthetic quartz) is used, the surface that is not the surface on the thin film layer formation side (back surface) of the base material is formed by sputtering thereafter. A conductive layer such as Cr is disposed from the side.
The material and thickness of each part, and each processing method are the same as in the first basic example, and the description thereof is omitted here.
The second example is also a method for manufacturing an electron beam transfer mask for low-speed electron beam proximity projection lithography LEEPL, but the present invention is not limited thereto.
Of course, the transfer mask for low-speed electron beam proximity projection lithography LEEPL manufactured according to the second example is also an example of the embodiment of the transfer mask for charged particle beam according to the present invention. Therefore, the description is omitted here.

It is process sectional drawing of the 1st example of embodiment of the manufacturing method of the transfer mask manufacturing method for charged particle beams of this invention. It is process sectional drawing of the 2nd example of embodiment of the manufacturing method of the manufacturing method of the transfer mask for charged particle beams of this invention. It is a figure for demonstrating the exposure in an EPL system. It is a figure for demonstrating the exposure in a LEEPL system.

Explanation of symbols

110 Substrate 115 Hole (also referred to as a recess)
116 Thin-walled portion 117 Through-hole portion (also referred to as opening)
120 Thin film layer 121 Pattern part 125 Opening part 127 Pattern area | region 210 Base material 215 Hole part (it is also called a recessed part)
216 Thin portion 217 Through hole (also referred to as opening)
220 Thin film layer 221 Pattern part 225 Opening part 227 Pattern area 610 EPL mask (Stencil mask for EPL system)
611 membrane (scatterer)
612 Opening 613 Non-opening 620 Electron beam 621 Image forming electron 625 Scattered electron beam 630, 635 Projection lens system 640 Aperture 641 Opening 650 Wafer 660 Resist 710 LEEPL mask (Stencil mask for LEEPL system)
711 membrane (absorber)
712 Opening 713 Non-opening 715 Support 720 (Spot-shaped) electron beam 750 Wafer 760 Resist

Claims (11)

Transfer mask for charged particle beam with stencil mask structure in which pattern to be transferred is formed in conductive thin film layer (membrane) consisting of absorber for absorbing charged particle beam or scatterer for scattering charged particle beam The method for producing a transfer mask for charged particle beam, comprising, in order, (a) an absorber for absorbing a charged particle beam on one surface of a plate-like substrate or scattering for scattering a charged particle beam A thin film layer forming step of disposing a conductive thin film layer comprising a body; and (b) a machining step of thinly machining a pattern forming region of the base material from a side that is not on the thin film layer side of the base material; c) a transfer pattern forming step of forming a pattern to be transferred to the thin film layer by dry etching or wet etching of the thin film layer; and (d) wet etching of the thin portion of the substrate remaining in the thin wall. Removed Te, passed through the base of the formation region of the pattern, and, a wet etching process to leave a thin film layer formed of a pattern, which carries out the plate-like substrate is a glass substrate for a photomask A method for producing a transfer mask for charged particle beams, wherein: Transfer mask for charged particle beam with stencil mask structure in which pattern to be transferred is formed in conductive thin film layer (membrane) consisting of absorber for absorbing charged particle beam or scatterer for scattering charged particle beam A method of manufacturing a transfer mask for charged particle beam, in which (a1) a machining step of thinly machining a pattern formation region of a plate-like substrate that is not on the thin film layer forming side; and (B1) A thin film layer arrangement in which a conductive thin film layer made of an absorber for absorbing charged particle beams or a scatterer for scattering charged particle beams is disposed on one surface of a substrate not on the machining side. And (c1) a transfer pattern forming step of forming a pattern to be transferred to the thin film layer by dry etching or wet etching of the thin film layer; and (d1) a thin substrate remaining on the thin wall And it is removed by wet etching, to penetrate the base material of the formation region of the pattern, and, a wet etching process to leave a thin film layer formed of a pattern, which carries out the plate-like substrate Photos A method for producing a transfer mask for charged particle beams, which is a glass substrate for a mask . 3. The method for manufacturing a transfer mask for charged particle beam according to claim 1, wherein the plate-like base material is not a conductive material, and the thin film of the base material is formed after the wet etching step. A method for producing a transfer mask for charged particle beam, comprising performing a conductive layer disposing step of disposing a conductive layer from a surface side that is not a surface on the layer forming side.   The method for manufacturing a transfer mask for charged particle beam according to any one of claims 1 to 3, wherein a cleaning process, an inspection process, and a correction process are performed as necessary after the transfer pattern forming process and before the wet etching process. A method for producing a transfer mask for charged particle beam, comprising performing one or more of the following:   The method for manufacturing a transfer mask for charged particle beam according to any one of claims 1 to 4, wherein the machining is performed using any one of cutting processing such as milling and sandblasting. A charged particle beam transfer mask manufacturing method.   6. A charged particle beam transfer mask according to claim 1, wherein the charged particle beam transfer mask is used for low-energy electron proximity projection lithography LEEPL (Low Energy Electron-Beam Proximity Projection Lithography). A method for producing a transfer mask for charged particle beam, characterized in that:   The method for producing a transfer mask for charged particle beam according to any one of claims 1 to 6, wherein the base material is a photomask substrate such as quartz glass (synthetic quartz) or low expansion glass. Manufacturing method of charged particle beam transfer mask.   The charged particle beam transfer mask manufacturing method according to any one of claims 1 to 7, wherein the thin film layer is a Cr single layer or a multilayer having a Cr layer as a main layer. Method for manufacturing a transfer mask for lines.   Transfer mask for charged particle beam with stencil mask structure in which pattern to be transferred is formed in conductive thin film layer (membrane) consisting of absorber for absorbing charged particle beam or scatterer for scattering charged particle beam The plate-like base material is used as a base material for the supporting base material that supports the thin film layer, and the formation region portion of the pattern to be transferred from the base material is not the side where the thin film layer is formed on the plate-like base material. It is a through-hole processed, and the substrate is made of a glass substrate such as quartz glass (synthetic quartz) for photomasks or low expansion glass, and the conductive thin film layer (membrane) is made of conductive light shielding for photomasks. A charged particle beam transfer mask comprising a film material.   The charged particle beam transfer mask according to claim 9, which is a charged particle beam transfer mask for low-energy electron proximity projection lithography LEEPL (Low Energy Electron-Beam Proximity Projection Lithography). Line transfer mask.   The charged particle beam transfer mask according to any one of claims 9 to 10, which is produced by the method for producing a charged particle beam transfer mask according to any one of claims 1 to 8. A charged particle beam transfer mask.