JP2014116362A - Dry etching device, dry etching method and photomask manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dry etching device capable of shortening the required time of a process, a dry etching method and a photomask manufacturing method.SOLUTION: The dry etching device which performs etching by irradiating a material 10 to be etched placed on a cathode 22 with plasma from an anode 23 opposing the material 10 to be etched, comprises: as a shield disposed between the material 10 to be etched and the anode 23 and capable of arbitrarily setting at least a shape or a size of an opening for transmitting plasma therethrough, at least one of an expanding/contracting shield 40 which is supported in the center of the anode 23 and can be expanded/contracted from the center towards an edge of the opening and a spacer 52; and a restrictor 30 which can be expanded/contracted from the edge of the opening towards the center. Etching processing is performed by irradiating the material 10 to be etched only in a region of which at least the shape or the area has been arbitrarily set, with plasma.

Description

  The present invention relates to a dry etching apparatus, a dry etching method, and a photomask manufacturing method, and more particularly, to a dry etching apparatus, a dry etching method, and a photomask manufacturing method suitable for etching only an arbitrary region.

In the etching process in the dry etching, a material to be etched other than a region covered with a resist or the like and serving as an etching mask is dug.
Therefore, in the case where only an arbitrary region is dry-etched, the material to be etched must be covered with an etching mask such as a resist and patterned after being patterned by electron beam drawing.

A conventional technique for forming a light shielding frame relating to the production of a reflective mask will be described with reference to FIG.
FIG. 1A to FIG. 1F are schematic cross-sectional views of a reflective mask blank for sequentially explaining each process of forming a light shielding frame in conventional reflective mask manufacturing. FIG. 1A shows a reflective mask blank in which a synthetic quartz substrate 16, a multilayer reflective layer 15, a protective layer 14, an absorption layer 13, a low reflective layer 12, and a resist film 11 are sequentially laminated on a back conductive layer 17. .

FIG. 1B shows a step of forming a pattern by exposing the resist film 11 by electron beam drawing and performing development processing. The resist film 11 patterned by the process shown in FIG. 1B is used as an etching mask. Next, in the step shown in FIG. 1C, the low reflection layer 12 and the absorption layer 13 are etched, and the resist film is also removed.
Next, in the step shown in FIG. 1D, second surfaces are formed on the upper surface of the low reflective layer film 12, the etched portions of the low reflective layer film 12 and the absorption layer 13, and the exposed surface of the protective layer 14 exposed by the etching. A resist film 18 is applied. Thereafter, the second resist film 18 is exposed by electron beam drawing, development processing is performed, and a pattern is formed by the process shown in FIG.

Thereafter, using the patterned second resist film 18 as an etching mask, in the step shown in FIG. 1F, the low reflective layer 12, the absorption layer 13, the protective layer 14, and the multilayer reflective layer 15 are etched to form a second layer. The resist film 18 is removed. By this step, the light shielding property of the EUV light is increased in the region dug up to the multilayer reflective film 15, and a light shielding frame is formed.
Thus, the manufacturing process in the conventional reflective mask manufacturing is longer than the manufacturing process in which the light shielding frame is not formed.

  Therefore, Patent Document 1 discloses a dry etching method capable of controlling pattern dimensions. The technique disclosed in Patent Document 1 is a plasma apparatus including a shutter (hereinafter referred to as a diaphragm) that can change the contact area between the inner wall surface of the chamber and the plasma. The reaction product generated from the inner wall surface is controlled to perform etching with an optimum pattern dimension.

JP-A-10-233386

However, in the dry etching method described in Patent Document 1, additional steps such as resist coating, electron beam drawing, and development are required in order to etch the multilayer reflective layer in the process of forming the light shielding frame for manufacturing the reflective mask. , The time required for the process becomes longer.
Accordingly, the present invention is intended to solve the above-described problems of the prior art, and a dry etching apparatus, a dry etching method, and a method that can shorten the time required for the process by etching only an arbitrary region. An object of the present invention is to provide a photomask manufacturing method.

  In order to achieve the above object, the invention according to claim 1 of the present invention provides an anode facing the material to be etched (10) with respect to the material to be etched (10) placed on the cathode (22). (23) In the dry etching apparatus for etching by irradiating with plasma, at least the shape or size of the opening arranged between the material to be etched (10) and the anode (23) and allowing the plasma to pass therethrough is arbitrary. At least one of the expansion shield (40) and the spacer (52) supported by the center of the anode (23) and capable of expanding from the center toward the edge of the opening is provided as a shield that can be set to And a diaphragm (30) that can expand and contract from the edge of the opening toward the center, and has at least a shape or an area with respect to the material to be etched (10). And irradiating the plasma region only to set the will, characterized in that a configuration which is etched (FIG. 2).

According to a second aspect of the present invention, in the dry etching apparatus according to the first aspect, the diaphragm (30) is arranged so as to be movable in a direction perpendicular to a direction in which the diaphragm (30) moves away from and approaches the material to be etched (10). A plurality of plates (30a), a diaphragm support (31) for movably supporting the plates (30a), and first moving means (301) for moving the plates (30a). (FIG. 2).
According to a third aspect of the present invention, in the dry etching apparatus according to the second aspect, the diaphragm (30) includes the plate (30a), the diaphragm support (31), and the first moving means (301). A second moving means (302) for moving the material to be etched (10) in a direction toward and away from the material to be etched (10) is further provided (FIG. 2).

According to a fourth aspect of the present invention, in the dry etching apparatus according to the first aspect, the expansion shield (40) is movable in a direction orthogonal to a direction in which the material to be etched (10) is separated and approached. A plurality of plates (40a) disposed on the plate, a shield support (41) for movably supporting the plates (40a), and third moving means (401) for moving the plates. (FIG. 2).
According to a fifth aspect of the present invention, in the dry etching apparatus according to the fourth aspect, the third moving means (401) includes the shield support (40) to which the expansion shield (40) and the spacer (52) are connected. 41) is provided with a detachable mechanism (Z) (FIG. 2).

According to a sixth aspect of the present invention, in the dry etching apparatus according to the fourth or fifth aspect, the expansion shield (40) includes the plate (40a), the shield support (41), and the third moving means (401). ) Is further provided with a fourth moving means (402) that moves in a direction approaching and separating from the material to be etched (10) (FIG. 2).
A seventh aspect of the present invention is the dry etching apparatus according to the sixth aspect, wherein the fourth moving means (402) includes a mechanism (X) that can be attached to and detached from the anode (23), and the third moving means (401). And a detachable mechanism (Y) (FIG. 2).

  The invention of claim 8 is the dry etching apparatus according to claim 7, wherein the expansion shield (40), the spacer (52), the shield support (41), the third moving means (401), and the The arrangement mechanism (Q) of the fourth moving means (402) further includes the expansion shield (40), the plurality of spacers (52), the shield support (41), A storage shelf (50) for storing the third moving means (401) and the fourth moving means (402), and the expansion shield (40) and one of the plurality of spacers (52) from the storage shelf (50). And the fourth moving means (402), the third moving means (401), the shield support (41), the expansion shield (40), and the spacer (52) are appropriately connected. Said A moving mechanism (51) that can be placed on the door (23), the moving mechanism (51) including the expansion shield (40), the spacer (52), the shield support (41), the first The third moving means (401) and the fourth moving means (402) can be appropriately returned to the storage shelf (50) (FIG. 2).

According to a ninth aspect of the present invention, in the dry etching apparatus according to the eighth aspect, the aperture (30), the expansion shield (40), the spacer (52), and the first to fourth moving means (301, 302). , 401, 402) includes either anodized or yttria (FIGS. 2 to 6).
A tenth aspect of the present invention is a dry etching method using the dry etching apparatus according to any one of the first to ninth aspects, wherein the shape and size of the aperture of the diaphragm (30) through which the plasma passes are determined. It is characterized in that at least one of the shape and area of the region irradiated with the plasma to the material to be etched (10) is changed by changing at least one of them.

The invention of claim 11 is a photomask manufacturing method characterized in that the material to be etched (10) is etched using the dry etching method of claim 10.
A twelfth aspect of the present invention is the photomask manufacturing method according to the eleventh aspect, comprising a step of forming a light shielding frame of a reflective mask by etching the material to be etched (10), and the light shielding. In the step of forming the frame, the light shielding frame is formed without applying a resist (FIG. 1).

  According to the present invention, it is possible to provide a dry etching apparatus, a dry etching method, and a photomask manufacturing method capable of reducing the time required for the process by etching only an arbitrary region.

It is a schematic cross-sectional view of a reflective mask blank for sequentially explaining each process of forming a light shielding frame in conventional reflective mask manufacturing. 1 is a schematic cross-sectional view showing a dry etching apparatus with a diaphragm, a stretch shield, and a spacer according to an embodiment of the present invention. It is a top view for demonstrating operation | movement of the aperture_diaphragm | restriction of the dry etching apparatus which concerns on embodiment of this invention. It is explanatory drawing for demonstrating operation | movement of the expansion / contraction shield of the dry etching apparatus which concerns on Example 1 of this invention. It is a top view for demonstrating operation | movement of the aperture_diaphragm | restriction and expansion / contraction shield of the dry etching apparatus based on Example 1 of this invention. It is a top view for demonstrating operation | movement of the aperture_diaphragm | restriction and spacer of the dry etching apparatus which concerns on Example 2 of this invention. It is a figure which shows the etching process result of light shielding frame formation by a prior art. It is a figure which shows the etching process result of light-shielding frame formation by the dry etching apparatus with an aperture_diaphragm | restriction and expansion / contraction shield based on embodiment of this invention. It is a figure which shows the etching process result of shading frame formation by the dry etching apparatus with a aperture_diaphragm | restriction and spacer which concerns on embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
First, a dry etching apparatus with a diaphragm and a stretch shield according to an embodiment of the present invention will be described in detail with reference to FIGS.

  FIG. 2 is a schematic sectional view showing a dry etching apparatus with a diaphragm, a stretch shield, and a spacer according to an embodiment of the present invention. As shown in FIG. 2, a dry etching apparatus 20 with a diaphragm and a stretch shield includes a chamber 21 having a gas supply port 24 and an exhaust port 25, and an anode ( An anode) 23 and a cathode (cathode) 22; an RF (high frequency) power source (high frequency oscillator) 28 connected between the cathode 22 and ground via a blocking capacitor 26 and an impedance matching unit (MB) 27; The aperture 30 is disposed between the material to be etched 10 and the anode 23, and includes a diaphragm 30 and a spread shield 40 that can change the size of the opening through which the plasma from the anode 23 passes.

  That is, in a dry etching apparatus that etches the material to be etched 10 placed on the cathode 22 by irradiating plasma from the anode 23 facing the material to be etched 10. As a shield that is disposed between and can arbitrarily set at least the shape or size of the opening through which the plasma passes, it is supported at the center of the anode 23 and can be expanded and contracted from the center toward the edge of the opening. The expansion / contraction shield 40 or the spacer 52 and the diaphragm 30 that can expand / contract from the edge of the opening toward the center are provided. The dry etching apparatus 20 has a configuration in which etching is performed by irradiating plasma only to a region whose shape or area is arbitrarily set with respect to the material to be etched 10 (FIG. 2).

  FIG. 3 is a plan view for explaining the operation of the aperture of the dry etching apparatus according to the embodiment of the present invention. FIG. 3A shows a state in which the diaphragm is fully opened, and FIG. 3B shows a state in which the diaphragm has a reduced opening area. As shown in FIG. 2 and FIG. 3, the diaphragm is a plurality of, for example, four plates 30 a, which are arranged so as to be movable in a direction orthogonal to the direction of approaching and separating from the material to be etched 10. A diaphragm support 31 that supports the movable body 30a and a first moving unit 301 that moves the plate 30a are provided.

Further, the diaphragm 30 includes a plate 30 a, a diaphragm support 31, and second moving means 302 that moves the first moving means 301 in a direction toward and away from the material to be etched 10.
That is, the diaphragm 30 includes a plurality of plates 30a that are arranged so as to be movable in a direction orthogonal to the direction in which the material to be etched 10 is separated and approached, and a diaphragm support 31 that supports each plate 30a so as to be movable. And first moving means 301 for moving the plate 30a (FIG. 2). The diaphragm 30 further includes second moving means 302 for moving the plate 30a, the diaphragm support 31 and the first moving means 301 in a direction approaching and separating from the material to be etched 10 (FIG. 2).

Next, Embodiment 1 of the present invention will be described with reference to FIGS.
FIG. 4 is an explanatory diagram for explaining the operation of the stretch shield of the dry etching apparatus according to the first embodiment of the present invention. FIG. 4A is a plan view showing a state in which the expansion / contraction shield is nearly fully closed with the light shielding area widened. FIG. 4B is a plan view showing a state where the expansion shield has narrowed the light shielding area. FIG. 4C is a perspective view for schematically explaining the relationship between the expansion / contraction shield and the third moving means for adjusting the light shielding area. As shown in FIGS. 2 and 4, the expansion shield 40 includes a plurality of, for example, four plates 40 a, which are arranged so as to be movable in a direction perpendicular to the direction of separating and approaching the material to be etched 10. A shield support 41 for movably supporting each plate 40a and a third moving means 401 for moving the plate 40a are provided, which are configured as shown in FIG.

Further, the expansion shield 40 includes a fourth moving unit 402 that moves the plate 40a, the diaphragm shield support 41, and the third moving unit 401 toward and away from the material to be etched 10. .
That is, the expansion / contraction shield 40 includes a plurality of plates 40a arranged so as to be movable in a direction perpendicular to the direction of separating and approaching the material 10 to be etched, and a shield support that supports each plate 40a so as to be movable. 41 and third moving means 401 for moving the plate (FIG. 2). The expansion shield 40 further includes fourth moving means 402 for moving the plate 40a, the shield support 41, and the third moving means 401 in a direction toward and away from the material to be etched 10 (FIG. 5). Moreover, the 4th moving means 402 is provided with the mechanism X which can be attached or detached to the anode 23, and the mechanism Y which can attach or detach the 3rd moving means 401 (FIG. 2). Furthermore, the 3rd moving means 401 is provided with the mechanism Z which can attach or detach the shield support body 41 to which the expansion / contraction shield 40 and the spacer 52 were connected (FIG. 2).

The dry etching apparatus 20 further includes an arrangement mechanism Q for the expansion shield 40, the spacer 52, the aperture support 31, the third moving unit 401, and the fourth moving unit 402. The arrangement mechanism Q includes a storage shelf 50 and a moving mechanism 51.
The storage shelf 50 stores the expansion shield 40, the plurality of spacers 52, the shield support 41, the third moving unit 401, and the fourth moving unit 402.

  The moving mechanism 51 selects the storage shelf 50, the expansion / contraction shield 40 and one of the plurality of spacers 52 from the storage shelf 50, the fourth movement unit 402, the third movement unit 401, the shield support 41, the expansion / contraction The shield 40 and the spacer 52 can be appropriately connected and placed on the anode 23. The moving mechanism 51 can appropriately return the expansion shield 40, the spacer 52, the shield support 41, the third moving means 401, and the fourth moving means 402 to the storage shelf 50 (FIG. 2).

In the dry etching apparatus 20, the material of the diaphragm 30, the expansion shield 40, the spacer 52, and the first to fourth moving means 301, 302, 401, 402 includes either alumite or yttria (FIGS. 3 to 3). 6).
In the dry etching apparatus 20 configured as described above, after the chamber 21 is evacuated to a predetermined degree of vacuum, the reactive gas is supplied from the gas supply port 24, and the reactive gas is exhausted through the exhaust port 25. Thereby, the inside of the chamber 21 is controlled to a predetermined pressure (about 0.1 mTorr to several hundreds mTorr). The material to be etched 10 is placed on the cathode 22. RF (high frequency) power is supplied to the cathode 22 from the RF (high frequency) power source 28 through the impedance matching unit 27 and the blocking capacitor 26 into the gas in the chamber 21.

  FIG. 5 is a plan view for explaining the operation of the aperture and expansion shield of the dry etching apparatus according to the first embodiment of the present invention. As shown in FIG. 5, before the plasma treatment, the area of the opening 30b formed by the four plates 30a is adjusted by the first moving means 301 so that only an arbitrary region of the material to be etched 10 can be etched. By adjusting the area of the expansion / contraction shield 40 formed by the four plates 40a by the third moving means 401, an opening 40d (see FIG. 5) excluding the region of the expansion / contraction shield 40 from the opening 30b is formed. The distance (height) between the plate 30a from the material to be etched 10 by the second moving means 302 and the plate 40a from the material to be etched 10 is adjusted by the fourth moving means 402.

  As described above, the plasma contact area can be freely varied with respect to the material to be etched by adjusting the distance (height) and opening area of the aperture 30 and the expansion shield 40 with respect to the material to be etched 10 before the plasma treatment. Thus, only an arbitrary region of the material to be etched can be etched.

  As described above, in the dry etching method using the dry etching apparatus 20, the shape and area of the region in which the material to be etched 10 is irradiated by changing at least one of the shape and the size of the opening of the aperture 30 through which the plasma passes. At least one of them was changed. Preferably, there is a photomask manufacturing method in which the material to be etched 10 is etched using this dry etching method. That is, it is preferable that the light shielding frame of the reflective mask is formed by etching the material to be etched 10 and that the light shielding frame is formed without applying a resist in the step of forming the light shielding frame. .

  The photomask manufacturing method according to the embodiment of the present invention does not perform steps such as resist coating, electron beam drawing, and development in the formation of a light-shielding frame for manufacturing a reflective mask. By adjusting the opening area, the plasma contact area is varied with respect to the material to be etched, and only an arbitrary region is etched. As a result, the etching area can be easily varied according to process requirements, and the productivity of the photomask can be improved.

As shown in FIG. 2, the etching apparatus 20 according to the first embodiment is a method for etching only an arbitrary region using a diaphragm 30 and a spread shield 40 that can move between the material to be etched 10 and the anode 23. explain.
Further, the etching apparatus 20 includes a retractable shield 40, a shield support 41, a storage shelf 50 for storing the third moving unit 401 and the fourth moving unit 402, and a fourth moving unit 402, which are provided in the chamber 21. The third moving means 401, the shield support 41, and the expansion shield 40 are sequentially connected, and they are taken out from the storage shelf 50 and placed on the anode 23, or those placed on the anode 23 are placed on the storage shelf 50. The moving mechanism 51 to carry in is provided. Hereinafter, a method of etching only an arbitrary region using the etching apparatus 20 including these will be described.

FIG. 3A shows a state where the area of the opening 30 b formed by the four plates 30 a is maximized by the first moving means 301. FIG. 3B shows a state where the area of the opening 30 b formed by the four plates 30 a is reduced by the first moving means 301.
FIG. 4A shows a state in which the plasma shielding region formed by the four plates 40 a is maximized by the third moving unit 401. FIG. 4B shows a state in which the area of the plasma shielding region formed by the four diaphragm plates 40 a is reduced by the third moving unit 401. The plates 40a overlap each other, and the minimum shielding area is the area of one plate 40a.

Since the plate 30a and the diaphragm support 31 of the diaphragm 30, the plate 40a of the expansion shield 40, the shield support 41, the third moving means 401, and the fourth moving means 402 are exposed to plasma during the etching process, they are resistant to plasma. Manufactured from anodized materials such as anodized or yttria.
The material to be etched 10 is similar to the case shown in FIG. 1B in which the synthetic quartz substrate 16, the multilayer reflective layer 15, the protective layer 14, the absorption layer 13, and the low reflective layer 12 are patterned on the back surface conductive layer 17. A reflective mask was used.

  When the expansion shield 40 is not used, the etching apparatus 20 etches the entire surface of the material to be etched in the state where the area of the opening 30b of the diaphragm 30 is maximum. Further, if the plate 30a is operated by the first moving means 301 and the area of the opening 30b of the diaphragm 30 is reduced, the area of the opening through which plasma passes through the material to be etched 10 can be freely changed.

  When the expansion shield 40 is used, the entire surface of the material to be etched is shielded from plasma when the plate 40a of the expansion shield 40 is operated by the third moving means 401 and the area of the plasma shield region of the expansion shield 40 is maximum. Is not etched. Further, the plate 30a is operated by the first moving means 301 to adjust the area of the opening 30b of the diaphragm 30, and the plate 40a is operated by the third moving means 401 to adjust the area of the plasma shielding region of the expansion shield 40. Thus, the opening area can be freely changed, and a desired frame width can be etched.

Further, by adjusting the height of the diaphragm 30 by the second moving means 302 and adjusting the height of the expansion shield 40 by the fourth moving means 402, the opening area through which the plasma with respect to the material to be etched 10 passes. It is also possible to make fine adjustments.
As described above, by adjusting the opening area through which the plasma passes through the material to be etched 10 by the diaphragm 30 and the expansion shield 40, only an arbitrary region can be etched.

As described above, by using the present etching apparatus 20, it is possible to vary the etching area according to the process requirements. For example, without performing steps such as resist coating, electron beam drawing, and development necessary for the formation of a light shielding frame in the production of a reflective mask, the height and opening area of the diaphragm 30 and the expansion shield 40 are adjusted before plasma processing, so It becomes possible to etch only an arbitrary region by changing the opening area through which the plasma passes through the etching material 10.
FIG. 7 shows the result of etching the light shielding frame in the conventional process (FIGS. 1A to 1F) in the light shielding frame forming process for manufacturing the reflective mask using a conventional dry etching apparatus. The positional shift shown in FIG. 7 indicates a shift amount between the main pattern area and the light shielding frame area.

In the light shielding frame forming process for manufacturing the reflective mask using the dry etching apparatus 20 having the diaphragm 30 of the present embodiment shown in FIG. 2, the diaphragm shown in FIG. 5 is used instead of the processes of FIGS. 1 (d) and (e). 30 and the expansion shield 40 are used to adjust the opening area 40d through which the plasma for the material to be etched passes. FIG. 8 shows the result of the etching process of FIG.
As is apparent from FIG. 8, the result of etching using the diaphragm 30 and the expansion shield 40 by the process of the present embodiment is the same as that of the conventional process. As a result, the etching area can be easily changed according to process requirements, and the productivity of the photomask can be improved.

In the second embodiment, a case where a spacer 52 is used instead of the expansion shield 40 shown in the first embodiment will be described.
FIG. 6 is a plan view for explaining the operation of the aperture and the spacer of the dry etching apparatus according to the second embodiment of the present invention. As shown in FIGS. 2 and 6, the spacer 52 has a quadrangular shape, and a quadrangular shape that shields the plasma irradiated to the material to be etched 10 is formed. Further, a plurality of such spacers 52 are provided, and the sizes of the spacers 52 are different. Since the spacer 52 is exposed to plasma during the etching process, the spacer 52 is manufactured from alumite or yttria, which is a plasma-resistant material.

The material to be etched 10 is similar to the case shown in FIG. 1B in which the synthetic quartz substrate 16, the multilayer reflective layer 15, the protective layer 14, the absorption layer 13, and the low reflective layer 12 are patterned on the back surface conductive layer 17. A reflective mask was used.
The etching apparatus 20 prepares a plurality of spacers 52, selects one of them, and sequentially connects the fourth moving means 402, the third moving means 401, the shield support 41, and the spacer 52 to the anode 23. Set up. During the etching process, the plasma is cut off in a region other than the region between the diaphragm 30 and the spacer 52, and the plasma contact area with the material to be etched 10 is limited. Moreover, the 4th moving means 402 which adjusts the height of the spacer 52 from the to-be-etched material 10 is provided. By adjusting the height of the spacer 52 with respect to the material to be etched 10 by the fourth moving means 402, it is possible to finely adjust the opening area through which the plasma passes through the material to be etched 10.

As described above, by adjusting the opening area through which the plasma passes through the material to be etched 10 by the spacer 52, only an arbitrary region can be etched.
By using the etching apparatus 20, the etching area can be varied according to the process requirements. For example, the material to be etched is adjusted by adjusting the height and opening area of the diaphragm 30 and the spacer 52 before the plasma treatment without performing the steps such as resist coating, electron beam drawing, and development necessary for the formation of the light-shielding frame in the production of the reflective mask. On the other hand, it is possible to etch only an arbitrary region by changing the opening area through which the plasma passes.

  In the characteristic process of Example 2, that is, in the light shielding frame forming process of manufacturing the reflective mask using the dry etching apparatus 20 having the spacer 52 shown in FIG. 2, as an alternative process of FIGS. 1 (d) and (e), The aperture area 52a through which the plasma for the material to be etched 10 passes is adjusted using the diaphragm 30 and the spacer 52 shown in FIG. FIG. 9 shows the result of the etching process up to the completed state shown in FIG.

As is apparent from FIG. 9, the result of etching using the diaphragm 30 and the spacer 52 is equivalent to that of the conventional process. As a result, the etching area can be easily changed according to process requirements, and the productivity of the photomask can be improved.
As described above, according to the present embodiment, it is possible to provide a dry etching apparatus, a dry etching method, and a photomask manufacturing method capable of reducing the time required for the process by etching only an arbitrary region. Is possible.

  DESCRIPTION OF SYMBOLS 10 ... Material to be etched, 11 ... Resist film, 12 ... Low reflection layer, 13 ... Absorption layer, 14 ... Protective layer, 15 ... Multilayer reflection layer, 16 ... Synthetic quartz substrate, 17 ... Back surface conductive layer, 18 ... Second resist DESCRIPTION OF SYMBOLS 20 ... Etching apparatus, 21 ... Chamber, 22 ... Cathode, 23 ... Anode, 24 ... Gas supply port, 25 ... Exhaust port, 26 ... Blocking capacitor, 27 ... Impedance matching device, 28 ... RF (high frequency) power supply, 301 DESCRIPTION OF SYMBOLS 1st moving means, 302 ... 2nd moving means, 30 ... Diaphragm, 30a ... Plate, 30b ... Opening, 31 ... Diaphragm support body, 401 ... 3rd moving means, 402 ... 4th moving means, 40 ... Expansion / contraction shield 40a ... Plate, 40d ... Opening, 41 ... Shield support, 50 ... Storage shelf, 51 ... Moving mechanism, 52 ... Spacer, 52 (a) ... Opening, Q ... Placement mechanism, X, Y, Z ... Detachable mechanism

Claims (12)

In a dry etching apparatus that etches a material to be etched placed on a cathode by irradiating plasma from an anode facing the material to be etched,
As a shield that is arranged between the material to be etched and the anode and can arbitrarily set at least the shape or size of the opening through which the plasma passes,
At least one of a stretch shield or a spacer supported by the center of the anode and capable of contracting from the center toward the edge of the opening;
A diaphragm capable of expanding and contracting from the edge of the opening toward the center;
A dry etching apparatus characterized in that an etching process is performed by irradiating the plasma only to a region whose shape or area is arbitrarily set with respect to the material to be etched.   The diaphragm includes a plurality of plates arranged so as to be movable in a direction perpendicular to the direction of separating and approaching the material to be etched, a diaphragm support that supports each of the plates so as to be movable, and the plate. The dry etching apparatus according to claim 1, further comprising first moving means for moving.   The said aperture | diaphragm | restriction is further provided with the 2nd moving means to move the said plate, the said aperture_diaphragm | restriction support body, and the said 1st moving means to the direction which approaches and leaves | separates with respect to the said to-be-etched material. Dry etching equipment.   The expansion and contraction shield includes a plurality of plates arranged to be movable in a direction orthogonal to a direction of separating and approaching the material to be etched, a shield support for movably supporting the plates, and The dry etching apparatus according to claim 1, further comprising third moving means for moving the plate. 5. The dry etching apparatus according to claim 4, wherein the third moving unit includes a mechanism that can attach and detach the shield support to which the expansion shield and the spacer are connected.   5. The expansion / contraction shield further includes fourth moving means for moving the plate, the shield support, and the third moving means in a direction approaching and separating from the material to be etched. Or the dry etching apparatus of 5.   The dry etching apparatus according to claim 6, wherein the fourth moving unit includes a mechanism that can be attached to and detached from the anode, and a mechanism that can attach and remove the third moving unit. An arrangement mechanism for arranging the expansion shield, the plurality of spacers, the shield support, the third moving unit, and the fourth moving unit;
The arrangement mechanism includes a storage shelf for storing the expansion shield, the plurality of spacers, the shield support, the third moving unit, and the fourth moving unit,
Select the expansion shield and one of the plurality of spacers from the storage shelf, and appropriately connect the fourth moving means, the third moving means, the shield support, the expansion shield, and the spacer. A moving mechanism that can be placed on the anode,
The moving mechanism can return the expansion shield, the spacer, the shield support, the third moving unit, and the fourth moving unit to the storage shelf as appropriate. The dry etching apparatus as described.   The dry etching apparatus according to claim 8, wherein a material of the diaphragm, the expansion shield, the spacer, and the first to fourth moving means includes any one of alumite and yttria. A dry etching method using the dry etching apparatus according to any one of claims 1 to 9,
By changing at least one of the shape and size of the aperture of the diaphragm through which the plasma passes, at least one of the shape and area of the region where the plasma is irradiated onto the material to be etched is changed. Dry etching method.   11. A photomask manufacturing method, comprising: etching a material to be etched using the dry etching method according to claim 10. It is a photomask manufacturing method of Claim 11, Comprising:
Forming a light shielding frame of a reflective mask by etching the material to be etched;
In the step of forming the light shielding frame, the light shielding frame is formed without applying a resist.

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