TWI422966B - Multitone photomask, photomask blank, method of manufacturing the multitone photomask, and pattern transfer method - Google Patents

Description

Multi-modulation reticle, reticle substrate, multi-module reticle manufacturing method, and pattern transfer method

The present invention relates to a multi-tone mask used in the manufacture of a flat panel display (hereinafter referred to as FPD) such as a liquid crystal display device, a photomask substrate for manufacturing the multi-tone mask, and the like. A method of manufacturing a modulated mask and a pattern transfer method using the multi-mode mask.

A TFT (Thin Film Transistor) substrate used for, for example, a liquid crystal display device is a photomask having a transfer pattern including a light-shielding portion and a light-transmitting portion formed on a transparent substrate, for example, 5 to 6 times of light lithography. The steps are made. In recent years, in order to reduce the number of photolithography steps, a multi-tone mask having a transfer pattern including a light-shielding portion, a semi-transmissive portion, and a light-transmitting portion is gradually formed on a transparent substrate (refer to Japanese Patent Laid-Open No. 2007-249198). Bulletin).

For the FPD manufacturer of the multi-mode mask, the in-plane distribution of the line width (CD (critical dimension)) of the transfer pattern formed on the multi-tone mask is reduced to achieve an excellent FPD. Performance is extremely important. Therefore, in the manufacture of a multi-mode mask, for example, for design values, it is necessary to strictly control the line width non-uniformity. For example, for the design line width, it is necessary to achieve a center value of ±0.1 μm, more preferably ±0.05 μm, and an in-plane distribution of 0.1 μm, more preferably an in-plane distribution of 0.05 μm.

In order to manufacture the above-mentioned multi-mode mask, for example, a step of preparing a reticle substrate having a semi-transparent film and a light-shielding film sequentially formed on the transparent substrate; and forming a predetermined region covering the light-shielding portion on the reticle substrate a first photoresist pattern, wherein the first photoresist pattern is used as a mask, and the light shielding film is etched to form a light shielding film pattern; and the first photoresist pattern is removed to form at least a cover on the mask substrate The semi-transmissive portion forms a second photoresist pattern in a predetermined region, and the light-shielding film pattern and the second photoresist pattern are used as a mask, and the semi-transmissive film is etched to form a semi-transmissive film pattern.

The reticle for FPD manufacturing has a large size, for example, a square having a side of 300 mm or more, or a mask having a manufacturing efficiency that is required to improve the panel manufacturing efficiency is a square having a side of 1000 mm or more. Therefore, as the etching method of the light shielding film, it is advantageous to perform wet etching without vacuum etching the chamber. However, the inventors have found that in the above-described method of manufacturing a multi-tone mask, if wet etching of a light-shielding film is performed, even if one portion of the in-plane etching is finished, and other portions reach a specific line width. (CD) etching is not yet finished, resulting in unevenness in the plane of the line width. In this case, it will be difficult to determine the end point of the etching. That is, if the etching is completed at the etching end time of the portion where the etching speed is faster, the other portion may cause a problem that the line width of the light-shielding pattern is larger than the design value. Further, if the etching time is extended corresponding to the portion where the etching rate is slow, the side portion is further etched to a portion where the etching rate is faster, resulting in the CD being smaller than the design value.

In other words, the inventors have found that in the above-described method of manufacturing a multi-tone mask, it is difficult to suppress a local change in the etching rate in the plane of the mask base. As a result of detailed investigation, it has been found that the shape of the transfer pattern to be formed tends to change on the side where the etching rate of the light-shielding film is large, or the side where the etching rate of the light-shielding film is small changes. As a result, there is a case where the difference between the line width and the design value of the light-shielding film pattern (CD Shift) is increased, or the etching of the light-shielding film is locally generated (the removal of the light-shielding film is poor), so that the quality of the multi-tone mask is lowered. Manufacturing yield has deteriorated.

An object of the present invention is to provide a multi-tone mask which can improve the quality of a multi-mode mask and improve the manufacturing yield regardless of the shape of the transfer pattern. A reticle substrate for manufacturing the multi-mode reticle, and a method of manufacturing the multi-mode reticle. Further, an object of the present invention is to provide a pattern transfer method which can improve the manufacturing yield of FPD or the like by using the above-described multi-tone mask.

A first aspect of the present invention is a multi-mode mask in which a specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on a transparent substrate, and the light shielding portion is electrically conductive. The etched equalizer film, the semi-transmissive film, and the light shielding film are sequentially laminated on the transparent substrate, and the semi-transmissive portion is sequentially laminated on the transparent layer by the etching equalizer film and the semi-transmissive film. The transparent portion is formed by exposing the transparent substrate.

A second aspect of the present invention is a multi-mode mask, characterized in that a specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on a transparent substrate, and the light shielding portion is provided. The conductive equalizer film, the semi-transmissive film, and the light shielding film are sequentially laminated on the transparent substrate, and the semi-transmissive portion is sequentially formed by the etching equalizer film and the semi-transparent film. Laminated on the transparent substrate, wherein the light transmitting portion exposes at least a portion of the etching equalizer film formed on the transparent substrate Made out.

A third aspect of the present invention is the multi-mode mask of the first or second aspect, wherein the etching equalizer film has conductivity of a sheet resistance of 10 k?/? or less.

A fourth aspect of the invention is the multi-mode mask of any one of the first to third aspects, wherein the etching equalizer film comprises a metal or a metal compound.

A fifth aspect of the invention is the multi-mode mask of any one of the first to fourth aspects, wherein the etch equalizer film has a transmittance for exposure light of 60% or more.

According to a sixth aspect of the invention, the multi-tone mask of any one of the first to fifth aspects, wherein a pattern line width of the light shielding portion included in the transfer pattern and a design value of the light shielding portion are The difference is 50 nm or less.

According to a seventh aspect of the present invention, in the aspect of the first aspect, the semi-transmissive film of the semi-transmissive portion has a film thickness smaller than that of the light shielding portion. The film thickness of the above semi-transmissive film is included.

The eighth aspect of the invention is the multi-modulation reticle of any one of the first to seventh aspects, wherein the semi-transmissive portion comprises: a first semi-transmissive portion, which is etched by the etching equalizer The film and the semi-transmissive film are sequentially laminated on the transparent substrate, and the second semi-transmissive portion is formed by exposing the etching equalizer film formed on the transparent substrate.

A ninth aspect of the present invention is a reticle substrate, wherein a semi-transmissive film and a light-shielding film are sequentially laminated on a transparent substrate, and the semi-transmissive film and the light-shielding film are respectively patterned. A specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on the transparent substrate, and a conductive etching is formed between the semi-transmissive film and the transparent substrate. Equalizer membrane.

A tenth aspect of the invention is the reticle substrate of the ninth aspect, wherein the etch equalizer film has a sheet resistance of 10 kΩ/□ or less.

The eleventh aspect of the invention is the reticle substrate of the ninth or tenth aspect, wherein the etch equalizer film comprises a metal or a metal compound.

According to a twelfth aspect of the present invention, in a method of manufacturing a multi-tone mask, a multi-tone mask having a specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on a transparent substrate. And a manufacturing method of the multi-modular reticle, comprising: preparing a reticle substrate, wherein the reticle substrate is sequentially laminated with a conductive etchant film, a semi-transparent film, and And a light shielding film; the first etching step of etching the light shielding film by using the first photoresist pattern formed on the mask base as a mask; and the second etching step of removing the first After the photoresist pattern, a second photoresist pattern is formed on the mask substrate that has been subjected to the first etching, and at least the second photoresist pattern is used as a mask to etch the light shielding film or the semi-transmissive film; In the first etching step, the in-plane potential distribution of the formed light-shielding film pattern is uniformized by the etching of the equalizer film.

According to a thirteenth aspect of the present invention, there is provided a method of manufacturing a multi-tone mask according to the twelfth aspect, comprising: a first etching step of forming a predetermined surface covering the light shielding portion on the photomask substrate a first photoresist pattern in the region, wherein the first photoresist pattern is used as a mask, the light shielding film is etched to form a light shielding film pattern, and a second etching step is performed to remove the first light After the pattern is formed, a second photoresist pattern covering at least a predetermined region of the semi-transmissive portion is formed on the mask base of the first etching, and at least the second photoresist pattern is used as a mask. The light transmissive film is etched to form a semi-transmissive film pattern.

A fourteenth aspect of the present invention is a pattern transfer method comprising the steps of: using a multi-tone mask according to any of the first to eighth aspects, using the ninth to eleventh aspects a multi-mode mask manufactured by any one of the mask bases, or a multi-mode mask obtained by the manufacturing method of the twelfth or thirteenth aspect, irradiating the object to be transferred with exposure light, and transferring the transfer pattern It is printed on a photoresist film formed on the above-mentioned transfer target.

According to the multi-modulation reticle, the reticle substrate, and the multi-module reticle manufacturing method of the present invention, the etch rate of the light-shielding film can be made uniform in the surface regardless of the shape of the transfer pattern, thereby improving the multi-tone mask The quality of the line width accuracy and the like improves the manufacturing yield. Further, according to the pattern transfer method of the present invention, the manufacturing yield of the FPD or the like can be improved by using the above-described multi-tone mask.

<Embodiment of the Invention>

Hereinafter, an embodiment of the present invention will be described with reference mainly to Figs. 1A, 1B, 2, and 6.

1A is a partial cross-sectional view (schematic diagram) of the multi-mode mask of the embodiment, and FIG. 1B is a partial portion of the photoresist pattern formed on the object to be transferred by using the pattern transfer step of the multi-mode mask. Sectional view. Fig. 2 is a schematic view showing the flow of a manufacturing process of the multi-tone mask of the embodiment. Fig. 6 is a schematic view showing a state in which the etching rate of the light-shielding film is made uniform by etching the equalizer film in the manufacturing process of the multi-mode mask of the embodiment.

(1) Composition of multi-tone mask

The multi-mode mask 100 shown in FIG. 1A is used for manufacturing a thin film transistor (TFT) such as an LCD (Liquid Crystal Display), a color filter, a PDP (plasma display panel), and the like. use. In addition, FIG. 1A exemplifies a laminated structure of a photomask, and the actual pattern is not necessarily the same.

The multi-mode mask 100 has a transfer pattern including: a light blocking portion 121 that blocks exposure light (having a light transmittance of about 0%) when the multi-mode mask 100 is used; and reduces transmittance of exposure light The semi-transmissive portion 122 of, for example, 5% to 60% (when the transmittance of the light-transmitting portion is sufficiently wide) is 100%; and the light-transmitting portion 123 that transmits 100% of the exposure light. The term "sufficiently broad" as used herein means that the resolution of the exposure optical system is sufficiently broad, that is, the change in the line width of the pattern does not affect the broadness of the transmittance, for example, a width of 20 μm square or more.

The light shielding portion 121 is formed by sequentially depositing a conductive etching equalizer film 111, a semi-transmissive film 112, and a light shielding film 113 on the transparent substrate 110. Further, the semi-transmissive portion 122 is sequentially laminated on the transparent substrate 110 by the etching equalizer film 111 and the semi-transmissive film 112, and the upper surface of the semi-transmissive film 112 is exposed. Further, the light transmitting portion 123 is formed by exposing the transparent substrate 110. Here, other films may be present between and above the films without departing from the effects of the present invention. It is not limited to the case where the upper surface of the light shielding film 113 constituting the light shielding portion 121 is exposed, and another film may be formed on the light shielding film 113. Further, as described below, the etching equalizer film 111 having a high transmittance may remain in the light transmitting portion 123 instead of exposing the upper surface of the transparent substrate 110. Further, the case where the etching equalizer film 111, the semi-transmissive film 112, and the light shielding film 113 are patterned is described below.

The transparent substrate 110 is configured to include, for example, quartz (SiO ₂ ) glass or a flat plate containing low-expansion glass such as SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , RO, R ₂ O, or the like. The main surface (surface and back surface) of the transparent substrate 110 is flat and smooth by polishing or the like. The transparent substrate 110 can be, for example, a square having a side of 300 mm or more, and can be, for example, a rectangle having a side of 1000 mm to 2400 mm. The thickness of the transparent substrate 110 may be, for example, 3 mm to 20 mm.

The etching equalizer film 111 is formed to have a film having a sheet resistance of, for example, 10 kΩ/□ or less, preferably 5 kΩ/□ or less, more preferably 2 kΩ/□ or less. The film thickness of the etching equalizer film 111 can be, for example, 20 Å to 500 Å, preferably 50 Å to 300 Å. The etching equalizer film 111 may be configured as a film containing a metal or a metal compound. As the metal, Cr, Al, CoW, Ni, Mo, or the like can be used, and as the metal compound, an oxide, a nitride, a carbide, an oxynitride, a carbonitride, a oxycarbonitride, or the like of the above metal can be used. However, if the metal content is too small, it is difficult to ensure the above conductivity, and therefore, it is preferable to secure a composition of a specific metal content. Further, it is preferable that the etching liquid (or etching gas) for etching the semi-transmissive film 112 has etching resistance. At this time, the etching equalizer film 111 can function as an etching stopper layer when the semi-transmissive film 112 is etched in the following manner.

The exposure light transmittance of the film for etching the equalizer film 111 is not particularly limited. Further, the etching equalizer film 111 is formed by patterning the light shielding film 113 and the semi-transmissive film 112, respectively, and after completing the function as an etching equalizer, the portion remaining in the light transmitting portion 123 can be removed. On the other hand, at least a portion of the etched equalizer film 111 remaining in the light transmitting portion 123 may be left as a part of the multi-tone mask 100. In such a case, it is preferable that the film used for etching the equalizer film 111 has an exposure light transmittance of 60% or more. For example, the etching equalizer film 111 may be left or a portion of the thinned portion may be left and used as the light transmitting portion 123 of the multi-tone mask 100. At this time, it is preferable to use the film which has an exposure light transmittance of 80% or more with respect to the transparent substrate 110 by etching the equalizer film 111. As a film material having a high transmittance which can be used at this time, for example, ITO (Indium Tin Oxide), ATO (Antimony Tin Oxide), zinc oxide, antimony tin alloy, magnesium hydroxide can be used. , tin oxide, etc. In such a case, it is more preferable that the transmittance of the etching equalizer film 111 with respect to the exposure light is 85% or more with respect to the transparent substrate.

Further, in the present embodiment, the transparent substrate 110 includes a light shielding portion 121 in which an etching equalizer film 111, a semi-transmissive film 112, and a light shielding film 113 are laminated; an etching equalizer film 111 and a semi-transmissive film are laminated. The semi-transmissive portion 122 of the 112; and the light-transmitting portion 123 of the transparent substrate 110 are exposed, but the second semi-transmissive portion in which at least a part of the etching equalizer film 111 remains may be included on the transparent substrate 110. That is, as described below, if the exposure light transmittance of the etching equalizer film 111 is appropriately selected, it can be used as a fourth-order photomask, and the transmittance can be adjusted by selecting the film thickness. The transmittance of the etching equalizer film 111 at this time is determined by the processing conditions of the elements to be manufactured using the multi-mode mask 100, but can be selected, for example, in the range of 5% to 80%.

The semi-transmissive film 112 includes a chromium compound and a compound containing at least cerium and molybdenum, and may include, for example, CrO, CrN, CrC, MoSix, MoSiN, MoSiON, MoSiCON, or the like. The semi-transmissive film 112 is configured to be etchable using a fluorine (F)-based etching liquid (or an etching gas). Further, it is preferable that the semi-transmissive film 112 has etching resistance to the etching liquid (or etching gas) for chromium. In this case, the semi-transmissive film 112 can function as an etching stopper layer when the light-shielding film 113 is etched using the etching solution for chromium as follows. Further, the thickness of the semi-transmissive film 112 constituting the semi-transmissive portion 122 may be reduced to be smaller than the thickness of the semi-transmissive film 112 constituting the light shielding portion 121. Thereby, the transmittance of the semi-transmissive portion 122 can be precisely adjusted to a desired value.

The film transmittance of the semi-transmissive film 112 to the exposure light is preferably 5% to 80%. More preferably 7% to 70%. By such a transmittance, the processing yield at the time of forming a display device such as an FPD can be improved. The film transmittance can be obtained by the selection of the above materials and the selection of the film thickness.

The light shielding film 113 is substantially composed of chromium (Cr) as a main component. Further, when a layer of a Cr compound (CrO, CrC, CrN, or the like) is provided on the surface of the light-shielding film 113, the surface can have a reflection suppressing function. The light shielding film 113 is configured to be etched using, for example, an etching solution containing chromium (ammonium nitrate) ((NH ₄ ) ₂ Ce(NO ₃ ) ₆ ) and perchloric acid (HClO ₄ ).

In FIG. 1B, a partial cross-sectional view of the photoresist pattern 4p formed on the transfer target 1 by the pattern transfer step using the multi-tone mask 100 is exemplified. The photoresist pattern 4p is formed by irradiating the positive-type resist film 4 formed on the to-be-transferred body 1 with the exposure light and developing it through the multi-mode mask 100. The transfer target 1 includes a substrate 2, and any of the processed layers 3a to 3c such as a metal thin film, an insulating layer, and a semiconductor layer which are sequentially laminated on the substrate 2, and the positive resist film 4 is formed in a uniform thickness. On the layer 3c to be processed. Further, it is possible to make the processed layer 3b resistant to the etching of the processed layer 3c, and the processed layer 3a is resistant to the etching of the processed layer 3b.

When the positive-type resist film 4 is irradiated with the exposure light through the multi-mode mask 100, the light-shielding portion 121 does not transmit the exposure light, and the amount of the light of the exposure light is in the order of the semi-transmissive portion 122 and the light-transmitting portion 123. Increase in stages. Further, in the region corresponding to each of the light blocking portion 121 and the semi-light transmitting portion 122, the film thickness of the positive resist film 4 is sequentially thinned, and is removed in a region corresponding to the light transmitting portion 123. Thereby, a photoresist pattern 4p having a different film thickness stepwise is formed on the transfer target 1 .

After the photoresist pattern 4p is formed, the processed layer 3c to 3a exposed in the region not covered by the photoresist pattern 4p (the region corresponding to the light transmitting portion 123) can be sequentially removed from the surface side (first etching) ). Then, the photoresist pattern 4p is ashed (thinned), and the thinnest region (the region corresponding to the semi-transmissive portion 122) is removed, thereby sequentially etching the newly exposed processed layers 3c, 3b (the first) 2 etching). By using the photoresist pattern 4p having different film thicknesses in this manner, the previous steps corresponding to two masks can be performed, thereby reducing the number of masks and simplifying the photolithography step.

(2) Method for manufacturing multi-tone mask

Next, a method of manufacturing the multi-tone mask 100 of the present embodiment will be described with reference to Fig. 2 .

(Photomask substrate preparation step)

First, as illustrated in FIG. 2(a), a mask base 100b formed by sequentially depositing a conductive etching equalizer film 111, a semi-transmissive film 112, and a light shielding film 113 on a transparent substrate 110 is prepared. In this manner, the mask base 100b of the present embodiment includes conductive portions of materials having a certain degree of conductivity (here, a semi-transmissive film 112 including a compound containing at least bismuth and molybdenum and Cr as a main component). The contact surface of the light shielding film 113).

The first photoresist film 131 is formed on the light shielding film 113. The first photoresist film 131 may be composed of a positive photoresist material or a negative photoresist material. In the following description, it is assumed that the first photoresist film 131 is formed of a positive photoresist material. The first photoresist film 131 can be formed by, for example, a spin coating or a slit coater.

(first etching step)

Next, the image is exposed by a laser scanner or the like, and a portion of the first photoresist film 131 is exposed to light, and the developer is supplied onto the first photoresist film 131 by a method such as a spray method to develop the film to form a light-shielding portion. The first photoresist pattern 131p of the predetermined region is formed at 121. A state in which the first photoresist pattern 131p is formed is exemplified in FIG. 2(b).

Then, the formed first photoresist pattern 131p is used as a photomask, and the light shielding film 113 is etched to form a light shielding film pattern 113p, and the upper surface of the semi-transmissive film 112 is partially exposed. A state in which the light shielding film pattern 113p is formed is exemplified in FIG. 2(c). The etching is performed by the above etching solution for chromium containing cerium ammonium nitrate ((NH ₄ ) ₂ Ce(NO ₃ ) ₆ ) and perchloric acid (HClO ₄ ). The etching liquid has electrical conductivity and functions as an electrolyte.

Furthermore, as the etching of the light shielding film 113 proceeds, if the semi-transparent film is exposed In the case of 112, the heterogeneous metal (the metal contained in each of the light-shielding film 113 and the semi-transmissive film 112) is immersed in the electrolytic solution (etching liquid) in a state of having a joint portion with each other.

Furthermore, as described above, when a conventional photomask substrate (a photomask substrate having a semi-transmissive film and a light-shielding film sequentially laminated on a transparent substrate and having no etching equalizer film) is used, there is an etching rate of the light-shielding film. Inconsistent in-plane. In particular, it has been found that the etching rate is locally lowered or increased due to the shape of the transfer pattern. According to the results of studies conducted by the inventors, etc., it has been confirmed that the wet etching behavior of the light-shielding film 113 from the start of etching to the exposure of the semi-transmissive film 112 is thereafter generated by etching, and the semi-transmissive film 112 is exposed. Variety. That is, it is considered that the etching behavior is shifted to a different state due to a new factor (change in the supply state of electrons) caused by the formation of the battery generated from the time point when the semi-transmissive film 112 is exposed. The so-called new state refers to a difference in the shape of the pattern in the plane, a difference in density, or a difference in the ratio of the area ratio of the light shielding portion to the semi-light transmission portion.

Further, the inventors think that there is a case where the line width of the light-shielding film pattern is partially different from the design value due to the above influence, or the etching of the light-shielding film locally is poor (the removal of the light-shielding film is poor), thereby making the multi-tone type The quality of the mask is lowered, and the manufacturing yield is deteriorated.

On the other hand, the mask base 100b of the present embodiment includes an etching equalizer film 111 having conductivity on the lower layer side of the semi-transmissive film 112. Thereby, regardless of the shape of the transfer pattern, the etching rate of the light-shielding film 113 is always maintained stable and uniform (the local variation of the etching rate of the light-shielding film 113 is suppressed). Thereby, if the etching end point is appropriately selected, it is possible to prevent the line width of the light-shielding film pattern 113p from being partially localized with the design value or locally causing etching failure of the light-shielding film 113 (defective removal of the light-shielding film 113). Further, the effect of etching the equalizer film 111 on the etch rate uniformity will be described later.

After the formation of the light shielding film pattern 113p is completed, the first photoresist pattern 131p is peeled off. Next, a second photoresist film 132 that covers the remaining light-shielding film 113 (light-shielding film pattern 113p) and the upper surface of the exposed semi-transmissive film 112 is formed. The second photoresist film 132 may include a positive photoresist material or a negative photoresist material. In the following description, it is assumed that the second photoresist film 132 is formed of a positive photoresist material. The second photoresist film 132 can be formed by a method such as spin coating or a slit coater. A state in which the second photoresist film 132 is formed is exemplified in FIG. 2(d).

(2nd etching step)

Next, the drawing exposure is performed by a laser drawing machine or the like, and a part of the second resist film 132 is exposed to light, and the developing solution is supplied to the second resist film 132 by a method such as a spray method to perform development, thereby forming at least a half. The light transmitting portion 122 forms a second photoresist pattern 132p of a predetermined region. A state in which the second photoresist pattern 132p is formed is exemplified in FIG. 2(e). Further, as illustrated in FIG. 2(e), the second photoresist pattern 132p may be formed not only to cover a predetermined region in which the semi-transmissive portion 122 is formed but also to cover a part or the entire portion of the light-shielding film pattern 113p.

Next, the formed light shielding film pattern 113p and the second photoresist pattern 132p are used as a mask, and the semi-transmissive film 112 and the etching equalizer film 111 are sequentially etched to form a semi-transmissive film pattern 112p and an etch equalizer film. The pattern 111p is formed, and the light-transmitting substrate 110 is partially exposed. Further, the etching of the semi-transmissive film 112 can be performed using the above-described fluorine (F)-based etching liquid (or etching gas). Further, the etching of the etching equalizer film 111 can be performed by an etching liquid (or etching gas) appropriately selected depending on the material constituting the etching equalizer film 111.

Next, the second photoresist pattern 132p is removed and removed, and the method of manufacturing the multi-mode mask 100 of the present embodiment is completed.

(3) Effect of etching the equalizer film

As described above, when the first etching step is performed, the etching is continued, and the light shielding film 113 is partially removed, whereby the semi-transmissive film 112 is partially exposed, whereby the light shielding film 113 and the semi-transmissive film 112 are bonded to each other. Part of the state is immersed in the state of the electrolyte (etching solution). Here, the light-shielding film 113 and the semi-transmissive film 112 are materials containing different metals and have a certain degree of conductivity. Therefore, the light-shielding film immersed in the electrolyte is similar to the semi-transmissive film, for example. A chemical battery such as a galvano battery, and from this point of time, the etching behavior of the light-shielding film 113 is governed by the electron transfer of the formed battery. Further, as a result, there is a case where the etching rate is lowered or increased. The effect of the heterogeneous metal having the joint portion immersed in the electrolytic solution on the etching rate (also referred to as a battery effect) will be described with reference to FIG.

Fig. 11(a) shows a measurement system for an etching rate, and shows a Cr-Mo laminate in which a Cr single-plate containing Cr, a Mo single-plate containing Mo, and a Cr-plate and a Mo-plate are overlapped (heterometal contact, The conduction is immersed in the above etching liquid for chromium.

Fig. 11 (b) is a graph showing the measurement results of the etching rates of the Cr single crystal plate, the Cr-Mo laminated plate, and the Mo single plate. According to FIG. 11(b), it is understood that the etching rate of Cr in the Cr-Mo laminate is reduced to less than half of the etching rate of Cr of the Cr single-plate. Further, it is understood that the etching rate of Mo in the Cr-Mo laminate is more increased than the etching rate of Mo in the Mo single plate. In other words, it is understood that when the heterogeneous metal that is electrically connected to each other is immersed in the electrolytic solution, the etching rate is affected, and the etching rate of the metal having a small ionization tendency (here, Cr) is lowered, and the ionization tendency is lowered. The etching rate of the large metal (here, molybdenum) increases. It can be understood from the above results that, in the wet etching of the multi-mode mask 100, the light shielding film 113 and the semi-transmissive film 112 including the mutually different metals have specific conductivity, respectively, and in a state in which the two are turned on. When it comes into contact with the etching liquid, an etching behavior different from that when only the light shielding film 113 is immersed in the etching liquid is generated, so that the etching rate changes.

Here, the exposed area in which the semi-transmissive film 112 is exposed by performing the first etching step is partially different depending on the shape of the transfer pattern. That is, the area of the exposed semi-transmissive film 112 is large or small due to the shape of the transfer pattern. According to the inventors' knowledge, in the manufacturing steps of the conventional multi-tone mask, the ratio of the exposed area of the semi-transmissive film 112 to the area of the pattern of the light-shielding film 113 in the middle of etching, the mutual distance, and the respective shape differences result in the above-mentioned The battery effect is strong, whereby the etching rate of the light-shielding film 113 cannot be made uniform in the plane. In other words, the shape of the transfer pattern has a portion where the etching rate of the light-shielding film 113 is largely changed, and a portion where the etching rate of the light-shielding film 113 is small is small, and the end point of the etching cannot be fixed in the plane. Regarding the phenomenon involved, the model examined by the inventors and the like is shown in FIG.

Fig. 7 is a schematic view showing a state in which the etching rate of the light-shielding film 113 is locally changed according to the shape of the transfer pattern in the manufacturing process of the conventional multi-tone mask. In FIG. 7, the semi-transmissive film 112 containing MoSi and the light-shielding film 113 containing Cr are sequentially laminated on the transparent substrate 110 without etching the equalizer film 111. Further, the photoresist pattern 131p formed on the light-shielding film 113 is used as a photomask, and the light-shielding film 113 is etched using the above-described etching solution (electrolyte solution) for chromium to form a light-shielding film pattern 113p, and the semi-transmissive film 112 is formed thereon. The surface is partially exposed. Further, in the right side of the figure, the exposed area of the semi-transmissive film 112 is large, and on the left side in the drawing, the exposed area of the semi-transmissive film 112 is small.

As shown in FIG. 7, since the semi-transmissive film 112 is exposed to contact the etching liquid (electrolyte), the Mo forming the semi-transmissive film 112 is ionized, for example, Mo is generated. Mo3 ⁺ +3e ^- equal reaction. Compared with the semi-transmissive film 112 on the left side in the smaller exposed area, more electrons are generated in the semi-transmissive film 112 on the right side in the larger exposed area. Electrons (e ^- ) generated by ionization of Mo are supplied from the semi-transmissive film 112 to the light shielding film 113. That is, more electrons are supplied to the light shielding film 113 (light shielding film pattern 113p) on the right side in the drawing than the light shielding film 113 (light shielding film pattern 113p) on the left side in the drawing. As a result, it is difficult to carry out the ionization reaction of Cr. At this time, the electron supply state from the Mo to the respective light-shielding film patterns 113p is different. Therefore, the potential of each of the light-shielding patterns 113P becomes uneven, and the etching rate of the light-shielding film 113 is partially uneven. For example, the decrease in the etching rate of the right side light-shielding film 113 in the drawing becomes more remarkable than the decrease in the etching rate of the light-shielding film 113 on the left side in the drawing.

Therefore, the inventors have actively studied how to reduce the potential of the battery effect generated by the shape of the transfer pattern, that is, the potential difference of the light-shielding film pattern 113p, and the potential difference of the light-shielding film pattern 113p is based on This is caused by the size of the exposed area of the semi-transmissive film 112 in the vicinity of the area of the light shielding film 113 to be etched. As a result, it has been found that the etched equalizer film 111 having conductivity can be disposed on the lower layer side of the semi-transmissive film 112, and the potentials of the formed light-shielding film patterns 113p can be made uniform, thereby suppressing etching of the light-shielding film 113. Local change in rate. That is, it has been found that by providing the etching equalizer film 111, the potentials of any portions in the plane of the light shielding film 113 are substantially equal, and the tendency of ionization when etching Cr is uniformized.

FIG. 6 shows a model in which the etching rate of the light-shielding film 113 is uniformized by etching the equalizer film 111 in the manufacturing process of the multi-mode mask 100 of the present embodiment (the potential of the light-shielding film pattern 113p is etched by the equalizer film). 111 and the case of uniformity). In FIG. 6, an etching equalizer film 111 containing a metal or a metal compound having a specific conductivity, a semi-transmissive film 112 containing MoSi, and a light shielding film 113 containing Cr as a main component are sequentially laminated on the transparent substrate 110. . In the same manner as in FIG. 7, the photoresist pattern 131p formed on the light-shielding film 113 is used as a mask, and the light-shielding film 113 is etched using the etching liquid (electrolyte solution) for chromium to form a light-shielding film pattern 113p. Further, the upper surface of the semi-transmissive film 112 is partially exposed as the etching progresses. Further, similarly to Fig. 7, in the right side of the figure, the exposed area of the semi-transmissive film 112 is large, and in the left side of the figure, the exposed area of the semi-transmissive film 112 is small.

As shown in FIG. 6, since the semi-transmissive film 112 is exposed and contacts the etching liquid (electrolyte), Mo which forms the semi-transmissive film 112 is ionized, for example, Mo is generated. Mo3 ⁺ +3e ^- equal reaction. Compared with the semi-transmissive film 112 on the left side in the smaller exposed area, more electrons are generated in the semi-transmissive film 112 on the right side in the larger exposed area. Electrons (e ^- ) generated by ionization of Mo flow from the semi-transmissive film 112 to the light shielding film 113. Here, since the etching equalizer film 111 has conductivity, the electrons generated in the right side of the drawing not only flow into the light shielding film 113 (light shielding film pattern 113p) on the right side in the drawing, but also pass through the etching equalizer film 111, the left side in the drawing. The semi-transmissive film 112 flows into the light shielding film 113 (light shielding film pattern 113p) on the left side in the drawing. Thereby, the potentials of the formed light-shielding film patterns 113p are uniformized, so that the etching rate of the light-shielding film 113 is locally uniformized.

The measurement results confirming the above effects will be described with reference to Figs. 8 to 10 .

FIG. 8 is a schematic view showing a state in which the exposed area of the semi-transmissive film 112 generated during etching is small with respect to the area of the light-shielding film to be etched when the light-shielding film 113 is etched, and FIG. 8(a) The sample 1 (the sample having the same laminated structure as the mask base 100b of the present embodiment) in which the etching equalizer film 111, the semi-transmissive film 112, and the light shielding film 113 are sequentially laminated on the transparent substrate 110 is etched. In the case, FIG. 8(b) shows that the sample 2 having the semi-transmissive film 112 and the light-shielding film 113 sequentially laminated on the transparent substrate 110 (having a sample having the same laminated structure as the previous multi-tone mask substrate) is etched. In the case, FIG. 8(c) shows a case where the sample 3 on which the light-shielding film 113 is formed on the transparent substrate 110 (the sample having the same laminated structure as the previous binary mask substrate) is etched. Further, etching is performed by applying a photoresist film to the surface of each sample to form a photoresist pattern in which only the photoresist is removed in the etching portion, and then supplying the Cr etching solution to the exposed light shielding film 113.

Further, FIG. 9 is a view showing a mode in which a semi-transmissive film 112 (a portion indicated by a symbol 201 in the figure) having an area larger than the area of the etching portion is exposed in the vicinity of the etching portion when the light shielding film 113 is etched. 9(a) shows a sample 4 having an etching equalizer film 111, a semi-transmissive film 112, and a light shielding film 113 sequentially laminated on a transparent substrate 110 (having the same layer as the mask substrate 100b of the present embodiment). FIG. 9(b) shows a sample 5 in which a semi-transmissive film 112 and a light-shielding film 113 are sequentially laminated on a transparent substrate 110 (having the same pattern as the conventional multi-tone mask substrate). In the case where the sample of the laminated structure is etched, FIG. 9(c) shows that the sample 6 on which the light-shielding film 113 is formed on the transparent substrate 110 (the sample having the same laminated structure as the previous binary reticle substrate) is etched. The situation. Further, in the same manner as in FIG. 8, the etching is performed by applying a photoresist film to the surface of each sample to form a photoresist pattern in which only the etching portion removes the photoresist, and then supplying the Cr etching solution to the exposed light shielding film 113.

Further, in the present measurement, in order to clearly grasp the action of the etching equalizer film 111, the etching conditions and patterns were designed. In other words, the etching time is longer than the actual etching time, and the pattern is arranged as shown in Figs. 8 and 9, whereby the condition for distinguishing the following CD Shift due to the presence or absence of the etching equalizer film 111 is selected. .

FIG. 10 is a graph showing the difference between the line width (the line width of the etching portion in FIGS. 8 and 9) and the design value (referred to as CD shift) in the measurement unit 200 of the light shielding film pattern 113p for the samples 1 to 6. In Fig. 10, the ◇ mark, the Δ mark, and the □ mark respectively indicate the CD shift (μm) in the samples 1, 2, and 3 of Fig. 8. Further, the ◆ mark, the ▲ mark, and the ? mark in Fig. 11 respectively indicate the CD shift (μm) in the samples 4, 5, and 6 of Fig. 9.

As shown in FIG. 10, each of the samples 1 to 6 was subjected to verification of etching of the light-shielding film 113 three times, and CD shift (μm) was measured for each verification. As a result, in the sample 1 (◇ mark) and sample 4 (◆ mark) having the same laminated structure as the mask base 100b of the present embodiment, the CD shift is always the same regardless of the exposed area of the semi-transmissive film 112. Dropped below 0.100 (μm). On the other hand, in the sample 2 (Δ mark) and the sample 5 (▲ mark) including the same laminated structure as the previous multi-tone mask substrate having no etching equalizer film 111, the semi-transmissive film 112 is known. As the exposed area becomes larger, the CD shift increases from 0.0500 (μm) to 0.300 (μm). Further, it can be seen that in the sample 3 (□ mark) and the sample 6 (■ mark) having the same laminated structure as the previous binary reticle base, since the battery effect is not generated, the CD shift is always reduced to 0.1000 (μm). )the following.

In addition, as described above, in the measurement, it was confirmed that the CD shift can be controlled to 0.1 μm or less. However, it is understood that the actual TFT manufacturing mask can have a CD Shift of 0.05 μm or less, and it is also possible to manufacture more. A reticle with a CD Shift of 0.03 μm or less.

As described above, according to the present embodiment, the etching equalizer film 111 can be provided regardless of the shape of the transfer pattern, and the change in the etching rate of the light shielding film 113 can be made uniform, thereby improving the quality of the multi-tone mask 100. Increase manufacturing yield. Moreover, according to the pattern transfer method using the multi-tone mask 100 of the present embodiment, the manufacturing yield of the FPD or the like can be improved.

Further, the effect of the present embodiment is remarkably exhibited in the case where the semi-transmissive film 112 and the light-shielding film 113 each have a certain degree of conductivity. This is because, in this case, the battery is formed by the first etching step (wet etching step). For example, when the semi-transmissive film 112 and the light-shielding film 113 each include a conductive material of 10 kΩ/□ or less and further 5 kΩ/□ or less, the effects of the embodiment can be remarkably obtained.

In addition, the etching equalizer film 111 of the present embodiment may have electrical conductivity to such an extent as to have an electron transporting action or a supply action for uniformizing the etching behavior in the plane. Further, it is more preferable to have higher conductivity (low sheet resistance value) than that of the semi-transmissive film 112 and the light-shielding film 113. Further, it is preferable to have a sheet resistance value of 1/5 or less of the sheet resistance value of each of the semi-transmissive film 112 and the light-shielding film 113. Thereby, even if the transfer pattern has various shape distributions and density distributions in the plane, the effect of smoothly supplying electrons can be sufficiently achieved, and the potential difference in the plane of the entire transfer pattern can be reduced.

<Another embodiment of the present invention>

The multi-mode mask 100' of the present embodiment is different from the above embodiment in that it is configured as a fourth-order photomask.

3A is a partial cross-sectional view (schematic view) of the multi-mode mask 100' of the present embodiment, and FIG. 3B is formed on the object to be transferred 1 by a pattern transfer step using the multi-mode mask 100'. A partial cross-sectional view of the photoresist pattern. Fig. 4 is a schematic view showing a flow of a manufacturing process of the multi-tone mask 100' of the embodiment.

(1) Composition of multi-tone mask

The multi-mode mask 100' of the present embodiment has a transfer pattern including: a light blocking portion 121 for blocking exposure light (transmittance of about 0%) when the multi-mode mask 100' is used; When the transmittance of light is reduced to 5% or more and 70% or less (when the transmittance of the sufficiently wide transparent portion 123 is 100%, the same applies hereinafter), it is preferable to reduce the first half to about 5% or more and 50% or less. The light transmitting portion 122a; the transmittance of the exposure light is reduced to 5% or more and 80% or less, preferably to the second semi-light transmitting portion 122b which is reduced to about 7% or more and 70% or less; and the transmission light is 100% transmitted. Light portion 123. In the above description, the term "sufficiently broad" means that the resolution of the exposure optical system is sufficiently wide, that is, the change in the line width of the pattern does not affect the broadness of the transmittance, for example, a width of 20 μm square or more.

Similarly to the above-described embodiment, the light-shielding portion 121 is formed by sequentially depositing a conductive etching equalizer film 111, a semi-transmissive film 112, and a light-shielding film 113 on the transparent substrate 110. Further, the first semi-transmissive portion 122a is formed in the same manner as the semi-transmissive portion 122 of the above-described embodiment, and the etching equalizer film 111 and the semi-transmissive film 112 are sequentially laminated on the transparent substrate 110. The second semi-transmissive portion 122b is formed by exposing the etching equalizer film 111 formed on the transparent substrate 110. Further, the light transmitting portion 123 is formed by partially exposing the transparent substrate 110 in the same manner as in the above embodiment. Here, not only the upper surface of the light shielding film 113 constituting the light shielding portion 121 but also the other film may be formed on the light shielding film 113. Further, the case where the etching equalizer film 111, the semi-transmissive film 112, and the light shielding film 113 are patterned is described below.

The configurations of the transparent substrate 110, the etching equalizer film 111, the semi-transmissive film 112, and the light shielding film 113 are the same as those of the above embodiment. Further, the thickness of the etching equalizer film 111 constituting the second semi-transmissive portion 122b may be reduced to be smaller than the thickness of the etching equalizer film 111 constituting the light shielding portion 121 and the first semi-light transmitting portion 122a. Thereby, the transmittance of the second semi-transmissive portion 122b can be precisely adjusted to a desired value.

Formed on the transferred by using the pattern transfer step of the multi-tone mask 100' A partial cross-sectional view of the photoresist pattern 4p' of the printed body 1 is exemplified in Fig. 3(b). The photoresist pattern 4p' is formed by irradiating the positive resist film 4 formed on the object to be transferred 1 with exposure light through the multi-mode mask 100'. The transfer target 1 includes a substrate 2, and any of the processed layers 3a to 3c such as a metal thin film, an insulating layer, and a semiconductor layer which are sequentially laminated on the substrate 2. The positive resist film 4 can be formed in advance in a uniform thickness. On the layer 3c to be processed. Further, it is possible to make the processed layer 3b resistant to etching by the processed layer 3c, and the processed layer 3a is resistant to etching by the processed layer 3b.

When the exposure light is irradiated to the positive-type resist film 4 via the multi-mode mask 100', the light-shielding portion 121 does not transmit the exposure light, and the amount of light of the exposure light is the first semi-transmissive portion 122a and the second semi-transparent portion. The order of the light portion 122b and the light transmitting portion 123 is increased stepwise. Further, the positive-type resist film 4 is thinned in the region corresponding to the light-shielding portion 121, the first semi-transmissive portion 122a, and the second semi-transmissive portion 122b, respectively, and corresponds to the light-transmitting portion 123. The area is removed. In this manner, a photoresist pattern 4p' having a different film thickness stepwise is formed on the transfer target 1.

When the photoresist pattern 4p' is formed, the processed layer 3c to 3a exposed in the region not covered by the photoresist pattern 4p' (the region corresponding to the light transmitting portion 123) can be sequentially removed from the surface side (the first) 1 etching). Next, the photoresist pattern 4p' is ashed (thinned), the thinnest region (the region corresponding to the second semi-transmissive portion 122b) is removed, and the newly exposed processed layers 3c, 3b are sequentially etched. Remove (second etching). Then, the photoresist pattern 4p' is further ashed (thinned), the film thickness is removed second only to the thinnest region (the region corresponding to the first semi-transmissive portion 122a), and the newly exposed processed layer 3c is Order etching removal (third etching). By In this manner, by using the photoresist pattern 4p' having a different film thickness step, the previous steps corresponding to the three masks are performed, so that the number of masks can be reduced, so that the photolithography step can be simplified.

(2) Method for manufacturing multi-tone mask

Next, a method of manufacturing the multi-tone mask 100' of the present embodiment will be described with reference to Fig. 4 .

(Photomask substrate preparation step)

First, as illustrated in FIG. 4(a), a mask base 100b formed by sequentially depositing a conductive etching equalizer film 111, a semi-transmissive film 112, and a light shielding film 113 on a transparent substrate 110 is prepared. The first photoresist film 131 is formed on the light shielding film 113.

(first etching step)

Then, the image is exposed by a laser scanner or the like, and a portion of the first photoresist film 131 is exposed to light, and the developer is supplied to the first photoresist film 131 by a method such as a spray method to develop the film to form a light-shielding portion 121. The first photoresist pattern 131p of the predetermined region is formed. A state in which the first photoresist pattern 131p is formed is exemplified in FIG. 4(b).

Next, the formed first photoresist pattern 131p is used as a photomask, and the light shielding film 113 is etched to form a light shielding film pattern 113p, and the upper surface of the semi-transmissive film 112 is partially exposed. A state in which the light shielding film pattern 113p is formed is exemplified in FIG. 4(c). The etching is performed by the above etching solution for chromium. This etching liquid has electrical conductivity and functions as an electrolytic solution.

Then, after the first photoresist pattern 131p is removed by lift-off or the like, the remaining light-shielding film 113 and the exposed upper surface of the semi-transmissive film 112 are formed. The second photoresist film 132. A state in which the second photoresist film 132 is formed is exemplified in FIG. 4(d).

(2nd etching step)

Next, the image is exposed by a laser scanner or the like, and a portion of the second resist film 132 is exposed to light, and the developer is supplied to the second resist film 132 by a method such as a spray method to develop the image, thereby forming at least the first portion. The semi-transmissive portion 122a forms a second photoresist pattern 132p of a predetermined region. A state in which the second photoresist pattern 132p is formed is exemplified in FIG. 4(e). Further, as illustrated in FIG. 4(e), the second photoresist pattern 132p may be formed not only to cover a predetermined region in which the first semi-transmissive portion 122a is formed but also to cover a part or the entire portion of the light-shielding film pattern 113p.

Next, the formed light shielding film pattern 113p and the second photoresist pattern 132p are used as a mask, and the semi-transmissive film 112 is etched to form a semi-transmissive film pattern 112p, and the upper surface of the etching equalizer film 111 is partially exposed. .

Next, after the second photoresist pattern 132p is removed by lift-off or the like, the third photoresist film 133 which covers the remaining light-shielding film 113, the semi-transmissive film 112, and the exposed upper surface of the etching equalizer film 111 is formed. A state in which the third photoresist film 133 is formed is exemplified in FIG. 4(f).

(3rd patterning step)

Next, the image is exposed by a laser scanner or the like, and a portion of the third photoresist film 133 is exposed to light, and the developer is supplied to the third photoresist film 133 by a method such as a spray method to develop the image, thereby forming at least the second portion. The third light-resistance pattern 133p of the predetermined area is formed in the semi-transmissive portion 122b. A state in which the third photoresist pattern 133p is formed is exemplified in FIG. 4(g). Furthermore, as shown in Figure 4(g) The third photoresist pattern 133p may be formed not only to cover a predetermined region in which the second semi-transmissive portion 122b is formed but also to cover a portion or an entire portion of the light-shielding film pattern 113p and the semi-transmissive film pattern 112p.

Next, the formed third photoresist pattern 133p is used as a mask, and the etching equalizer film 111 is etched to form an etching equalizer film pattern 111p, and the upper surface of the transparent substrate 110 is partially exposed. Then, the third photoresist pattern 133p is removed by lift-off or the like, thereby completing the method of manufacturing the multi-mode mask 100' of the present embodiment.

According to this embodiment, the same effects as those of the above embodiment can be exhibited. That is, regardless of the shape of the transfer pattern, the etching equalizer film 111 can be provided to uniformize the change in the etching rate of the light shielding film 113, thereby improving the quality of the multi-tone mask 100' and improving the manufacturing yield. . Further, according to the pattern transfer method using the multi-tone mask 100' of the present embodiment, the manufacturing yield of the FPD or the like can be improved.

<Another embodiment of the present invention>

The embodiment of the present invention has been specifically described above, but the present invention is not limited to the embodiment described above, and various modifications can be made without departing from the spirit and scope of the invention.

For example, as illustrated in FIG. 5, the light transmitting portion 123 of the multi-mode mask 100 may be configured to expose the etching equalizer film 111 formed on the transparent substrate 110.

1. . . Transferred body

2. . . Substrate

3a, 3b, 3c. . . Processed layer

4. . . Positive photoresist film

4p, 4p'. . . Resistive pattern

100, 100'. . . Multi-tone mask

100b. . . Photomask base

110. . . Transparent substrate

111. . . Etched equalizer film

111p. . . Etched equalizer film pattern

112. . . Semi-transparent film

112p. . . Semi-transparent film pattern

113. . . Sunscreen

113p. . . Sun mask pattern

121. . . Shading

122. . . Semi-transparent part

122a. . . First semi-transmission section

122b. . . Second semi-transmission section

123. . . Translucent part

131. . . First photoresist film

131p. . . First photoresist pattern

132. . . Second photoresist film

133. . . Third photoresist film

200. . . Measurement department

201. . . The semi-transmissive film 112 having a larger area than the area of the etched portion

1A is a partial cross-sectional view (schematic diagram) of a multi-mode mask according to an embodiment of the present invention, and FIG. 1B is a pattern transfer step by using the multi-tone mask. A partial cross-sectional view of the photoresist pattern formed on the transfer target.

2(a) to 2(f) are schematic diagrams showing the flow of a manufacturing process of a multi-tone mask according to an embodiment of the present invention.

3A is a partial cross-sectional view (schematic diagram) of a multi-mode mask according to another embodiment of the present invention, and FIG. 3B is a photoresist formed on the object to be transferred by using a pattern transfer step of the multi-mode mask. A partial section of the pattern.

4(a) to 4(h) are schematic diagrams showing the flow of a manufacturing step of a multi-tone mask according to another embodiment of the present invention.

Fig. 5 is a partial cross-sectional view (schematic diagram) of a multi-mode mask according to still another embodiment of the present invention.

Fig. 6 is a schematic view showing a state in which the etching rate of the light-shielding film is made uniform by etching the equalizer film in the manufacturing process of the multi-mode mask according to the embodiment of the present invention.

Fig. 7 is a schematic view showing a state in which the etching rate of the light-shielding film is locally changed by the shape of the transfer pattern in the manufacturing process of the conventional multi-tone mask.

8 is a schematic view showing a state in which the exposed area of the semi-transmissive film is small when the light-shielding film is etched, and FIG. 8(a) shows that an etching equalizer film, a semi-transmissive film, and the like are sequentially laminated on the transparent substrate. When the sample 1 of the light-shielding film is etched, FIG. 8(b) shows a case where the sample 2 in which the semi-transmissive film and the light-shielding film are sequentially laminated on the transparent substrate is etched, and FIG. 8(c) shows the case of the transparent substrate. The sample 3 on which the light-shielding film was formed was etched.

9 is a schematic view showing a state in which the exposed area of the semi-transmissive film is large when the light-shielding film is etched, and FIG. 9(a) shows that an etching equalizer film, a semi-transmissive film, and the like are sequentially laminated on the transparent substrate. When the sample 4 of the light-shielding film is etched, FIG. 9(b) shows a case where the sample 5 in which the semi-transmissive film and the light-shielding film are sequentially laminated on the transparent substrate is etched, and FIG. 9(c) shows the case of the transparent substrate. The sample 6 on which the light shielding film was formed was etched.

Fig. 10 is a graph showing the measurement results of the difference between the line width of the light-shielding film pattern and the design value.

Fig. 11 is a schematic view showing an effect of bonding of a heterogeneous metal immersed in an electrolytic solution to affect an etching rate, wherein Fig. 11(a) shows a measurement system for an etching rate, and Fig. 11(b) shows a Cr single plate and a Cr-constituting composition. The measurement results of the etching rates of the Cr plate of the Mo laminate, the Mo plate constituting the Cr-Mo laminate, and the Mo single plate.

100‧‧‧Multi-mode mask

110‧‧‧Transparent substrate

111‧‧‧ Etched Equalizer Film

112‧‧‧ Semi-transparent film

113‧‧‧Shade film

121‧‧‧Lighting Department

122‧‧‧ semi-transmission department

123‧‧‧Transmission Department

Claims (14)

A multi-modular reticle is characterized in that a specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on a transparent substrate, and the light shielding portion is etched by conductivity The equalizer film, the semi-transmissive film, and the light shielding film are sequentially laminated on the transparent substrate, and the semi-transmissive portion is sequentially laminated on the transparent substrate by the etching equalizer film and the semi-transmissive film. The light transmitting portion is formed by exposing the transparent substrate. A multi-modular reticle is characterized in that a specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed on a transparent substrate, and the light shielding portion is etched by conductivity The equalizer film, the semi-transmissive film, and the light shielding film are sequentially laminated on the transparent substrate, and the semi-transmissive portion is sequentially laminated on the transparent substrate by the etching equalizer film and the semi-transmissive film. The light transmitting portion is formed by exposing at least a part of the etching equalizer film formed on the transparent substrate. The multi-modulation reticle of claim 1 or 2, wherein the etch equalizer film has a sheet resistance of 10 kΩ/□ or less. A multi-modular reticle of claim 1 or 2, wherein said etch equalizer film comprises a metal or a metal compound. The multi-modulation reticle of claim 1 or 2, wherein the etch equalizer film has a transmittance for exposure light of 60% or more. The multi-mode mask of claim 1 or 2, wherein a difference between a line width of the light-shielding portion included in the transfer pattern and a line width of a design value of the light-shielding portion is 50 nm or less. The multi-mode mask of claim 1 or 2, wherein a thickness of the semi-transmissive film included in the semi-transmissive portion is smaller than a thickness of the semi-transmissive film included in the light-shielding portion. The multi-transmission mask of claim 1 or 2, wherein the semi-transmissive portion comprises: a first semi-transmissive portion, which is sequentially laminated on the transparent substrate by the etching equalizer film and the semi-transmissive film. And the second semi-transmissive portion is formed by exposing the etching equalizer film formed on the transparent substrate. A reticle substrate, characterized in that a semi-transmissive film and a light-shielding film are sequentially laminated on a transparent substrate, and the semi-transmissive film and the light-shielding film are respectively patterned to be processed on the transparent substrate A specific transfer pattern including a light shielding portion, a light transmitting portion, and a semi-light transmitting portion is formed thereon, and a conductive equalizer film is formed between the semi-transmissive film and the transparent substrate. The reticle substrate of claim 9, wherein the etch equalizer film has a sheet resistance of 10 kΩ/□ or less. The reticle substrate of claim 9 or 10, wherein the etch equalizer film comprises a metal or a metal compound. A method for manufacturing a multi-modular reticle, characterized in that it is transparent A method of manufacturing a multi-tone mask including a light-shielding portion, a light-transmitting portion, and a specific transfer pattern of the semi-transmissive portion is formed on the substrate, and the method for manufacturing the multi-tone mask includes the steps of preparing a mask base. The mask base is formed by sequentially laminating a conductive etching equalizer film, a semi-transmissive film, and a light shielding film on the transparent substrate; and a first etching step of forming the first layer on the mask substrate The photoresist pattern is used as a mask to etch at least the light-shielding film, and a second etching step is performed after the first photoresist pattern is removed, and a second photoresist pattern is formed on the mask substrate via the first etching And etching the light shielding film or the semi-transmissive film at least the second photoresist pattern as a mask; and forming the above-described etching equalizer film in the first etching step The in-plane potential distribution of the light-shielding film pattern is uniform. The method of manufacturing a multi-mode mask according to claim 12, further comprising: a first etching step of forming a first photoresist pattern covering the predetermined region of the light shielding portion on the mask substrate, and Using the first photoresist pattern as a mask, etching the light shielding film to form a light shielding film pattern, and a second etching step of removing the first photoresist pattern and then performing the first Forming a second photoresist pattern covering at least a predetermined region of the semi-transmissive portion on the etched mask base, and etching the semi-transmissive film to form a semi-transparent film by using at least the second resist pattern as a mask Light film pattern. A pattern transfer method comprising the steps of: using a multi-tone mask as claimed in claim 1 or 2, or using a multi-tone mask manufactured by the reticle substrate of claim 9 or 10, or by The multi-mode mask obtained by the method of claim 12 or 13, wherein the transfer target is irradiated with an exposure light, and the transfer pattern is transferred to a photoresist film formed on the transfer target.