EUV mask blank and photomask produced by using the EUV mask blank

Abstract

Extreme ultraviolet (EUV) mask blank (100) comprising: a substrate (110) having a first surface (110a); a reflective layer (120) having first reflective layers (121) and second reflective layers (122) alternately stacked on the first surface (110a) of the substrate (110); a cover layer (140) on the reflective layer (120); and a hydrogen absorber layer (130) between the reflective layer (120) and the cover layer (140), wherein the hydrogen absorber layer (130) contains a material having a lattice structure configured to dissolve hydrogen therein and is in contact with the cover layer (140), wherein the hydrogen absorber layer (130) comprises at least one of vanadium (V), manganese (Mn), iron (Fe), zirconium (Zr), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), cesium (Cs) or boron carbide (B 4 C).

Description

BACKGROUND

[0001] The present disclosure relates to extreme ultraviolet (EUV) mask blanks and associated photomasks.

[0002] With the rapid development of information media, the functions of semiconductor devices have evolved dramatically. To be competitive, high integration of semiconductor devices with low cost and high quality may be required. For high integration, the distance between the structures of semiconductor devices can be gradually reduced. A photolithography process that uses an ArF excimer laser as a light source may have limitations in realizing a linewidth of 32 nm or less. To realize a linewidth of 32 nm or less, immersion photolithography, double patterning, and the like have been introduced, each with its own limitations.

[0003] US 2016 / 0147139 A1 discloses a substrate having a multilayer reflective film formed on the substrate, comprising a layer containing Si as a high refractive index material and a layer containing a low refractive index material, the layers being periodically laminated; a Ru protective film formed on the multilayer reflective film to protect the multilayer reflective film; and a barrier layer formed between the multilayer reflective film and the Ru protective film to prevent migration of Si to the Ru protective film, wherein the surface layer of the multilayer reflective film facing the substrate is the layer containing Si, and at least a part of the Si is diffused into the blocking layer.

[0004] To address the above and other problems, a photolithography apparatus using extreme ultraviolet (EUV) light as a light source was introduced. However, extreme ultraviolet light can be greatly attenuated by the atmosphere and can be absorbed by many materials, and may be incompatible with a transmissive photomask used in an ArF photolithography process. Accordingly, a photomask having a reflective layer is typically used in an extreme ultraviolet photolithography process. SUMMARY

[0005] Aspects of the present disclosure provide an extreme ultraviolet (EUV) mask blank having a hydrogen absorber layer capable of storing and / or releasing hydrogen. The invention is defined by the appended independent claims. Further embodiments of the invention are subject to the dependent claims.

[0006] Aspects of the present disclosure also provide a photomask that can be used in an EUV lithography process and has a hydrogen absorber layer capable of storing and / or releasing hydrogen.

[0007] Aspects of the present disclosure also provide a method of manufacturing a semiconductor device using a photomask having a hydrogen absorber layer.

[0008] According to embodiments of the present disclosure, an extreme ultraviolet (EUV) mask blank comprises: a substrate having a first surface and a second surface opposite to each other; a reflective layer having first reflective layers and second reflective layers alternately stacked on the first surface of the substrate; a cap layer on the reflective layer; and a hydrogen absorber layer between the reflective layer and the cap layer, wherein the hydrogen absorber layer is configured to store hydrogen and is in contact with the cap layer.

[0009] According to embodiments of the present disclosure, an extreme ultraviolet (EUV) mask blank comprises: a substrate of a low thermal expansion material (LTEM) having a first surface and a second surface opposite each other; a reflective layer comprising a periodic molybdenum (Mo) / silicon (Si) multilayer on the first surface of the LTEM substrate; a first absorber layer on the reflective layer, wherein the first absorber layer is formed of a transition metal and comprises at least one of vanadium (V), manganese (Mn), iron (Fe), zirconium (Zr), palladium (Pd), hafnium (Hf), tantalum (Ta), rhodium (Rh), or gold (Au); a cap layer on the first absorber layer, wherein the cap layer is formed of one of ruthenium (Ru) and a ruthenium compound;and a second absorber layer on the cover layer opposite to the first absorber layer.;

[0010] According to embodiments of the present disclosure, a photomask comprises: a substrate having a first surface and a second surface opposite each other; a reflective layer, which is a periodic molybdenum (Mo) / silicon (Si) multilayer, on the first surface of the substrate; a cap layer on the reflective layer; a hydrogen absorber layer between the reflective layer and the cap layer, the hydrogen absorber layer being configured to store hydrogen and being in contact with the cap layer; a light absorption structure on the cap layer, the light absorption structure having an opening for passing extreme ultraviolet light therethrough; and a conductive coating film on the second surface of the substrate.

[0011] However, aspects of the present disclosure are not limited to those discussed herein. The above and other aspects of the present disclosure will become more apparent to one of ordinary skill in the art to which the present disclosure pertains by reference to the detailed description below. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other aspects and features of the present disclosure will become more apparent by describing embodiments thereof in detail with reference to the accompanying drawings, in which: Fig. 1 is a diagram illustrating an extreme ultraviolet (EUV) mask blank according to some embodiments of the present disclosure; Fig. 2 is a diagram illustrating an EUV mask blank according to some embodiments of the present disclosure; Fig. 3 is a diagram illustrating an EUV mask blank according to some embodiments of the present disclosure; Fig. 4 is a diagram illustrating a photomask according to some embodiments of the present disclosure; Fig. 5 is a diagram illustrating a photomask according to some embodiments of the present disclosure; Fig. 6 schematically illustrates a lithography apparatus according to some embodiments of the present disclosure; Fig. 7A and Fig. 7B are diagrams for explaining problems of a comparative photomask and effects of a hydrogen absorber layer of the photomask according to some embodiments of the present disclosure; and Fig. 8 to 11 are diagrams illustrating intermediate steps of a method of manufacturing a semiconductor device according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS

[0013] Some elements shown in this description may be exaggerated or reduced in size to facilitate understanding. This means that some drawings may not be to scale.

[0014] Fig. 1 is a diagram illustrating an extreme ultraviolet (EUV) mask blank according to some embodiments of the present disclosure. For example, the extreme ultraviolet mask blank 100 may be a substrate for fabricating a photomask that can be mounted in a photolithography apparatus that uses extreme ultraviolet light as a light source.

[0015] Referring to Fig. 1, an EUV mask blank 100 according to some embodiments of the present disclosure includes a mask substrate 110, a reflective layer 120, a hydrogen absorber layer 130, a cap layer 140, a light absorber layer 150, and a conductive coating film 160.

[0016] The mask substrate 120 may be made of a dielectric, glass, a semiconductor, or a metallic material. In some embodiments, the mask substrate 110 may be made of a material having a low thermal expansion coefficient. For example, the mask substrate 110 may have a thermal expansion coefficient of 0 ± 1.0 × 10 -7 / °C at 20 °C.

[0017] Furthermore, the mask substrate 110 may be made of a material having a desired smoothness, flatness, and / or resistance to a cleaning solution. The term "and / or" encompasses any and all combinations of one or more of the associated listed items. For example, the mask substrate 110 may be made of a synthetic quartz glass, fused silica, aluminosilicate glass, soda-lime glass, a low thermal expansion material (LTEM) glass, such as SiO 2 -TiO 2 -based glass (binary (SiO 2 -TiO 2 ) or ternary (SiO 2 -TiO 2 -SnO 2)), crystallized glass obtained by precipitating a solid β-quartz solution, single-crystal silicon, or SiC. The mask substrate 110 included in the EUV mask blank may need to have low thermal expansion characteristics. Accordingly, in some embodiments, the mask substrate 110 may be made of, for example, a multi-component glass material.

[0018] The mask substrate 110 may have a first surface 110a and a second surface 110b that are opposite to each other. For example, the first surface 110a of the mask substrate 110 may have a flatness of approximately 50 nm or less. The second surface 110b of the mask substrate 110 may have a flatness of approximately 500 nm or less. Each of the first surface 110a and the second surface 110b of the mask substrate 110 may have a root mean square (RMS) surface roughness of approximately 0.15 nm or less, but the present disclosure is not limited thereto. As used herein, the terms first, second, third are merely used to distinguish one direction, region, portion, or element from another.

[0019] The reflective layer 120 may be disposed on the first substrate 110a of the mask substrate 110. The reflective layer 120 may reflect extreme ultraviolet (EUV) light. The reflective layer 120 may have a multilayer mirror structure. The reflective layer 120 may have material layers having a high refractive index and material layers having a low refractive index alternately stacked a plurality of times.

[0020] The reflective layer 120 may include first reflective layers 121 and second reflective layers 122 alternately stacked. The reflective layer 120 may include a periodic multilayer including the first reflective layers 121 and the second reflective layers 122. The reflective layer 120 may include the first reflective layers 121 and the second reflective layers 122 alternately and repeatedly formed in approximately 20 to 60 cycles.

[0021] The first reflective layer 121 and the second reflective layer 122 may form a reflection pair 125. The reflective layer 120 may have approximately 20 to 60 reflection pairs 125. However, it should be understood that more or fewer reflection pairs 125 may be used as needed.

[0022] For example, the reflective layer 120 may comprise a periodic molybdenum (Mo) / silicon (Si) multilayer, a periodic Mo compound / Si compound multilayer, a periodic ruthenium (Ru) / Si multilayer, a periodic beryllium (Be) / Mo multilayer, a periodic Si / niobium (Nb) multilayer, a Si / Mo / Ru multilayer, a periodic Si / Mo / Ru / Mo multilayer, or a periodic Si / Ru / Mo / Ru multilayer.

[0023] The material of the reflective layer 120 and the thickness of each reflective layer 120 can be adjusted according to the wavelength band or range of the applied EUV light and / or the reflectivity of the EUV light required in the reflective layer 120.

[0024] In the EUV mask blank 100 according to some embodiments of the present disclosure, the reflective layer 120 is described as comprising a periodic molybdenum (Mo) / silicon (Si) multilayer. For example, the first reflective layer 121 may be formed from molybdenum, and the second reflective layer 122 may be formed from silicon. Alternatively, the first reflective layer 121 may be formed from silicon, and the second reflective layer 122 may be formed from molybdenum.

[0025] Although in Fig. 1 that the number of first reflective layers 121 included in the reflective layer 120 is the same as the number of second reflective layers 122 included in the reflective layer 120, the present disclosure is not limited thereto. In the reflective layer 120, a difference between the number of first reflective layers and the number of second reflective layers 122 may be equal to one. That is, there may be one more of the first reflective layers 121 than the second reflective layers 122 in the stack 120, or vice versa.

[0026] The reflective layer 120 can be formed using DC sputtering, RF sputtering, ion beam sputtering, or the like, but the present disclosure is not limited thereto. For example, in the case of forming a periodic Mo / Si multilayer by ion beam sputtering, a Si film and a Mo film can be alternately formed over a cycle in which a Si film is deposited by using a Si target as a target and an Ar gas as a sputtering gas, and a Mo film is deposited by using a Mo target as a target and an Ar gas as a sputtering gas.

[0027] The hydrogen absorber layer 130 may be formed on the reflective layer 120. The hydrogen absorber layer 130 thus serves or comprises a material configured to absorb hydrogen ions (H + ), which is generated from outside a photomask 200 (see Fig. 6) or hydrogen atoms, which are formed by reducing hydrogen ions (H + ) and to store them in the hydrogen absorber layer 130.

[0028] The hydrogen absorber layer 130 can store the absorbed hydrogen in a lattice structure. The hydrogen in the lattice structure can be located at an interstitial site rather than at a lattice site of the lattice structure.

[0029] The hydrogen absorber layer 130 may comprise a material having a relatively high hydrogen solubility.

[0030] When the hydrogen absorber layer 130 comprises a metal, the hydrogen absorber layer 130 may comprise a metal that has a small change in enthalpy when hydrogen is absorbed in the metal. The hydrogen absorber layer 130 may comprise a metal in which a change in the enthalpy of a hydrogen dissolution reaction is equal to ±0.5 (eV / absorbed hydrogen) or less. The hydrogen absorber layer 130 may comprise at least one of titanium (Ti), vanadium (V), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), molybdenum (Mo), palladium (Pd), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), or cesium (Cs). The metal that may be included or enclosed in the hydrogen absorber layer 130 may be a transition metal or a typical metal.

[0031] As one example, the hydrogen absorber layer 130 may be a single or monolithic film made of one of titanium (Ti), vanadium (V), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), molybdenum (Mo), palladium (Pd), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), or cesium (Cs). As another example, the hydrogen absorber layer 130 may be a multi-metal film comprising a first metal layer and a second metal layer made of different metals.

[0032] When the hydrogen absorber layer 130 comprises a metal alloy, the hydrogen absorber layer 130 may comprise an alloy containing titanium (Ti). For example, the hydrogen absorber layer 130 may comprise an alloy having a body-centered cubic structure. The hydrogen absorber layer 130 may comprise one of a Ti-Fe-based alloy, a Ti-Mn-based alloy, a Ti-Cr-based alloy, or a Ti-Fe-V-based alloy.

[0033] The hydrogen absorber layer 130 may be a ceramic material, for example a film made of boron carbide (B 4 C) is manufactured.

[0034] The hydrogen absorber layer 130 may be formed using, for example, DC sputtering, RF sputtering, ion beam sputtering, or the like, but the present disclosure is not limited thereto.

[0035] In some embodiments, the hydrogen absorber layer 130 may have a thickness of, for example, 5 to 100 Å.

[0036] In an extreme ultraviolet mask blank according to some embodiments of the present disclosure, the hydrogen absorber layer 130 may be in contact with the reflective layer 120 placed thereunder. Herein, the term "contact" may mean that no film exists intervening between the hydrogen absorber layer 130 and the reflective layer 120. In contrast, when an element is referred to as being "on" or "adjacent to" another element (e.g., a layer or structure), it may be touching or contacting the other element, or intervening elements may also be present. Likewise, spatially relative terms such as "below," "under," "lower," "above," "upper," "higher," and the like are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0037] Effects of the hydrogen absorber layer 130 will be described later with reference to the Fig. 6 to 7B are described.

[0038] The cover layer 140 may be disposed on the hydrogen absorber layer 130. The cover layer 140 may be in contact with the hydrogen absorber layer 130. The hydrogen absorber layer 130 may be disposed between the cover layer 140 and the reflective layer 120.

[0039] The cover layer 140 may serve to protect the reflective layer from mechanical damage and / or chemical damage.

[0040] The capping layer 140 may be made of ruthenium (Ru) or a ruthenium compound. The capping layer 140 may be a ruthenium film or a ruthenium compound film. The ruthenium compound may be formed of ruthenium (Ru) and Nb, Zr, Mo, Y, B, or La, or combinations thereof. The capping layer 140 may have a thickness of 5 to 100 Å.

[0041] The light absorber layer 150 may be disposed on the cover layer 140. The light absorber layer 150 may be made of a material that has a relatively low reflectivity of extreme ultraviolet light while absorbing extreme ultraviolet light. The light absorber layer 150 may be made of a material that has a desired chemical resistance. Additionally, the light absorber layer 150 may be made of a material that can be removed by etching or the like.

[0042] The light absorbing layer 150 may be made of a material containing Ta as a main component. In some embodiments, the light absorbing layer 150 may include tantalum (Ta) as a main component and at least one element selected from hafnium (Hf), silicon (Si), zirconium (Zr), germanium (Ge), boron (B), nitrogen (N), or hydrogen (H). For example, the light absorbing layer 150 may be formed of TaN, TaHf, TaHfN, TaBSi, TaBSiN, TaB, TaBN, TaSi, TaSiN, TaGe, TaGeN, TaZr, TaZrN, or combinations thereof.

[0043] The conductive coating film 160 may be disposed on the second surface 110b of the mask substrate 110. The conductive coating film 160 may be used to form the photomask 200 (see Fig. 6), which is manufactured using an extreme ultraviolet mask blank, to a chuck of a lithography apparatus during a photolithography process.

[0044] The conductive coating film 160 may comprise a material including tantalum (Ta) or a material including chromium (Cr) that has conductivity. For example, the conductive coating film 160 may be formed of at least one of Cr, CrN, or TaB.

[0045] Alternatively, the conductive coating film 160 may comprise metal oxide or metal nitride having conductivity. For example, the conductive coating film 160 may comprise at least one of titanium nitride (TiN), zirconium nitride (ZrN), hafnium nitride (HfN), ruthenium oxide (RuO 2 ), zinc oxide (ZnO 2 ) or iridium oxide (IrO 2 ).

[0046] Fig. 2 is a diagram illustrating an EUV mask blank according to some embodiments of the present disclosure. For simplicity of description, a description will be focused on differences from the Fig. 1 can be manufactured.

[0047] Referring to Fig. 2, the EUV mask blank 100 may further comprise a silicide layer 135 located between two surfaces (interface silicide layer 135) according to some embodiments of the present disclosure.

[0048] The interface silicide layer 135 may be disposed between the reflective layer 120 and the hydrogen absorber layer 130. The interlayer silicide layer 135 may comprise a silicide material.

[0049] For example, the interface silicide layer 135 may comprise a material obtained by silicidating the metal contained in the hydrogen absorber layer 130. In one example, if the hydrogen absorber layer 130 comprises a metal (M), the interface silicide layer 135 may comprise M-Si with the silicided metal (M). In another example, if the hydrogen absorber layer 130 comprises a transition metal, the interface silicide layer 135 may comprise a material obtained by silicidating the transition metal.

[0050] Fig. 3 is a diagram illustrating an EUV mask blank according to some embodiments of the present disclosure. For simplicity of description, a description will be made focusing on differences from Fig. 1.

[0051] Referring to Fig. 3, the EUV mask blank 100 may further comprise a low reflectivity layer, referred to herein as low reflectivity layer 170, according to some embodiments of the present disclosure.

[0052] The low-reflective layer 170 may be disposed on the light absorber layer 150. The low-reflective layer 170 may have a relatively low reflectivity in a wavelength band of the inspection light, for example, a wavelength band of approximately 160 to 260 nm, during the inspection of structural elements formed in the photomask 200 (see Fig. 6), which are manufactured using the EUV mask blank 100. Accordingly, the reflective layer 120 can serve to achieve sufficient contrast.

[0053] The low-reflective layer 170 may be made of at least one of, for example, TaBO, TaBNO, TaOH, or TaONH. The low-reflective layer 170 may be formed by a sputtering process, but the present disclosure is not limited thereto.

[0054] Fig. 4 is a diagram illustrating a photomask according to some embodiments of the present disclosure. Fig. 5 is a diagram illustrating a photomask according to some embodiments of the present disclosure.

[0055] The photomask 200 according to some embodiments of the present disclosure may be a reflective photomask that may be used in a photolithographic process that uses an EUV wavelength range, for example, an exposure wavelength of approximately 13.5 nm.

[0056] Furthermore, the photomask 200 according to some embodiments of the present disclosure may be formed by structuring the light absorber layer 150 and / or the low-reflective layer 120 formed in the EUV mask blank 100 of the Fig. 1 to 3. For example, the photomask of the Fig. 4 by structuring the light absorber layer 150 of the Fig. 1 and the photomask of the Fig. 5 can be achieved by structuring the light absorber layer 150 of the Fig. 2 can be produced.

[0057] In the photomask 200 according to some embodiments of the present disclosure, since the mask substrate 110, the reflective layer 120, the hydrogen absorbing layer 130, the cap layer 140, and the conductive coating film 160 are substantially similar to those described with reference to the Fig. 1 to 3 are described, further descriptions thereof are omitted.

[0058] Referring to the Fig. 4 and Fig. 5, the photomask 200 may include the mask substrate 110, the reflective layer 120, the hydrogen absorber layer 130, the cap layer 140, the conductive coating film 160, and a light absorption structure 155 according to some embodiments of the present disclosure.

[0059] The light absorption structure 155 may be disposed on the cover layer 140. The light absorption structure 155 may have an opening 155x for passing extreme ultraviolet light therethrough.

[0060] In Fig. 4, the reflective layer 120 may be in contact with the hydrogen absorber layer 130.

[0061] In Fig. 5, the interface silicide layer 135 may be interposed between the reflective layer 120 and the hydrogen absorber layer 130.

[0062] Although not shown, it is not necessary to say that in the Fig. 4 and Fig. 5 a low-reflective layer structure in which the low-reflective layer 170 (see Fig. 3) is structured, may further be formed on the light absorption structure 155.

[0063] Fig. 6 schematically illustrates a lithography apparatus according to some embodiments of the present disclosure.

[0064] The lithography apparatus according to some embodiments of the present disclosure may be an apparatus used in a photolithography process that uses extreme ultraviolet light as an exposure wavelength.

[0065] The lithography apparatus according to some embodiments of the present disclosure may be an apparatus that forms the photomask of the Fig. 4 and Fig. 5 used.

[0066] In the lithography apparatus according to some embodiments of the present disclosure, the photomask 200 is substantially similar to that described with reference to the Fig. 1 to 5, and further description thereof will be omitted.

[0067] Referring to Fig. 6, a lithography apparatus according to some embodiments of the present disclosure may include a main chamber 1100, a first sub-chamber 1110, a second sub-chamber 1120, a photomask or reticle stage module 1130 (including a reticle stage 1200), a reticle stage power supply 1300, a source 1400 configured to provide exposure light, reflection mirrors 1501 and 1502 for an illumination system, reflection mirrors 1601, 1602, 1603, and 1604 for an optical projection system, and a wafer stage 1700.

[0068] The main chamber 1100 includes the first sub-chamber 1110, the second sub-chamber 1120, the reticle stage module 1130, the illumination system reflection mirrors 1501 and 1502, the projection optical system reflection mirrors 1601, 1602, 1603, and 1604, and the wafer stage 1700. The interior of the main chamber 1100 can be maintained in a vacuum state.

[0069] The first sub-chamber 1110 may be placed in the main chamber 1100. At least one of the illumination system reflection mirrors 1501 and 1502 may be arranged in the first sub-chamber 1110.

[0070] The exposure light from the source 1400, which has passed through the first sub-chamber 1110 after being reflected by the illumination system reflection mirrors 1501 and 1502, can reach the photomask 200 attached to the reticle stage 1200. To increase the reflection efficiency of the exposure light, the interior of the first sub-chamber 1110 can be maintained in a vacuum state.

[0071] The second sub-chamber 1120 may be placed in the main chamber 1100. At least one of the projection optical system reflection mirrors 1601, 1602, 1603, and 1604 may be arranged in the second sub-chamber 1120.

[0072] The exposure light reflected from the surface of the photomask 200 can be reflected by the projection optical system reflection mirrors 1601, 1602, 1603, and 1604 and irradiated onto the wafer on the wafer stage 1700. To increase the reflection efficiency of the exposure light, the interior of the second sub-chamber 1120 can be maintained in a vacuum state.

[0073] The reticle stage module 1130 may be placed in the main chamber 1100 to be spaced apart from the first sub-chamber 1110 and the second sub-chamber 1120. The reticle stage module 1130 may include the reticle stage 1200, the photomask 200, and the like.

[0074] The reticle stage 1200 may be located in an upper portion of the main chamber 1100. The photomask 200 may be mounted on the reticle stage 1200. The reticle stage 1200 may be operable to perform a scanning operation.

[0075] The photomask 200 reflects the exposure light that has passed through the first sub-chamber 1110 toward the second sub-chamber 1120.

[0076] The reticle stage power supply 1300 may be electrically connected to the photomask 200 and the reticle stage 1200. The reticle stage power supply 1300 is connected to the reticle stage 1200 and the photomask 200, so that an electrostatic force is generated between the reticle stage 1200 and the photomask 200. Accordingly, the photomask 200 may be fixed to the reticle stage 1200 by the electrostatic force.

[0077] The source 1400 may be located outside the main chamber 1100. The source 1400 may provide the exposure light used in the photolithography process. The source 1400 may irradiate the exposure light onto the illumination system reflection mirrors 1501 and 1502 in the first sub-chamber 1110.

[0078] The source 1400 may be, but is not limited to, a discharge produced plasma (DPP) EUV light source, a laser produced plasma (LPP) EUV light source, a hybrid EUV light source, a synchrotron EUV light source, or the like.

[0079] The reflection mirrors 1501, 1501, 1601, 1602, 1603, and 1604 may be placed in the first sub-chamber 1110 and the second sub-chamber 1120. One or more of the reflection mirrors 1501, 1502, 1601, 1602, 1603, and 1604 may be formed of an oblique incidence mirror in which the exposure light irradiated from the source 1400 is incident on the reflection surface of the mirror at an oblique incidence angle, or a multi-layer mirror in which the reflection surface is a multi-layer.

[0080] To transfer a fine pattern onto the wafer, the projection optical system reflection mirrors 1601, 1602, 1603, and 1604 may have high resolution. The number of reflection mirrors 1601, 1602, 1601, 1602, 1603, and 1604 may be, for example, 6, but is not limited thereto.

[0081] The wafer stage 1700 may be located in a lower portion of the main chamber 1100. The wafer may be mounted on or otherwise supported by the wafer stage 1700.

[0082] The wafer stage 1700 may be movable for micro-alignment. Additionally, the wafer stage 1700 may be movable in a specific direction for the photolithography process.

[0083] The Fig. 7A and Fig. 7B are diagrams of a comparative photomask 2001 for explaining effects of the hydrogen absorber layer of the photomasks according to embodiments of the present disclosure. For convenience of description, the Fig. 7A and Fig. 7B no individual components contained in a comparison photomask 2001.

[0084] In the Fig. 6 and Fig. 7A there is a hydrogen (H 2 ) flow within the lithography device to transmit extreme ultraviolet light and to reduce or prevent collector contamination. Since the lithography device is placed in a hydrogen atmosphere, hydrogen ions (H + ) by extreme ultraviolet light generated in source 1400.

[0085] The generated hydrogen ions (H+) can penetrate into the comparative photomask 2001 while moving in the lithography device. The penetrated hydrogen ions (H +) can be reduced to hydrogen atoms by acquiring secondary electrons, which are generated in a photolithography process using extreme ultraviolet light.

[0086] Due to the incoming hydrogen ions (H + ) and the reduced hydrogen atoms, a 200cr high hydrogen concentration region can be formed in the comparative photomask 2001. When the hydrogen atoms (H atoms) meet in the 200cr high hydrogen concentration region, hydrogen gas bubbles GB can be generated in the 200cr high hydrogen concentration region.

[0087] In Fig. 7B, the hydrogen gas bubbles GB can be accumulated in the 200cr high hydrogen concentration region in a gaseous state. Due to the accumulation of the hydrogen gas bubbles GB, a hydrogen bubble H_B can be formed in the comparative photomask 2001.

[0088] The hydrogen bubble H_B in the comparison photomask 2001 may render the comparison photomask 2001 unusable, thereby reducing the reliability of the photolithography process. Furthermore, since the comparison photomask 2001 must be remanufactured, the process cost may increase.

[0089] However, the photomask 200 according to some embodiments of the present disclosure includes the distinct hydrogen absorber layer 130 capable of storing hydrogen (or otherwise includes material(s) configured to store hydrogen). The hydrogen reduced in the photomask 200 may be trapped or dissolved in the lattice of the hydrogen absorber layer 130.

[0090] When hydrogen is dissolved in the hydrogen absorber layer 130, hydrogen in the photomask 200 can be prevented or suppressed from being released into a gaseous state. Accordingly, the hydrogen absorber layer 130 can suppress the generation of a hydrogen bubble in the photomask 200.

[0091] Accordingly, the lifetime of the photomask 200 having the hydrogen absorbing layer 130 can be increased, thereby reducing the cost of manufacturing the photomask 200 and the like.

[0092] The Fig. 8 to 11 are diagrams illustrating intermediate steps of methods for manufacturing a semiconductor device according to some embodiments of the present disclosure.

[0093] The semiconductor device manufacturing methods according to some embodiments of the present disclosure may include a manufacturing method using the photomask of the Fig. 4 and Fig. 5.

[0094] Referring to Fig. 8, a mask film 310 may be formed on a substrate.

[0095] The substrate 300 may be a silicon substrate or may include other materials such as silicon-on-insulator (SOI), silicon germanium, silicon germanium-on-insulator (SGOI), indium antimonide, a lead tellurium compound, indium arsenide, indium phosphide, gallium arsenide, or gallium antimonide, but the present disclosure is not limited thereto.

[0096] The substrate 300 may include a circuit element having a conductive pattern and a semiconductor pattern. The substrate 300 may include an insulating film and metal wiring within the insulating film.

[0097] When the substrate 300 includes a circuit element, the circuit element may be, for example, but is not limited to, a fin-type transistor (FINFET) having a channel region having a fin-shaped structure, a tunnel FET, a transistor having a nano-wire, a transistor having a nano-sheet, or a three-dimensional (3D) transistor, a bipolar junction transistor, a laterally double-diffused MOS (LDMOS) transistor, or a planar transistor.

[0098] The mask film 310 may include at least one of an insulating material, a semiconductor material, or a conductive material.

[0099] A photosensitive film 320 may be formed on the mask film 310.

[0100] Referring to the Fig. 9 to 11, the mask film 310 may be formed using a photolithography process 330 using the photomask 200 (see Fig. 6). Accordingly, a mask pattern 315 can be formed on the substrate 300.

[0101] In Fig. 9, a device pattern may be transferred to the photosensitive film 320 by using the photolithography process 330. The photolithography process 330 may utilize the exposure light reflected from the photomask 200.

[0102] In Fig. 10, the device pattern transferred to the photosensitive film 320 may be developed to form a photosensitive pattern 325 on the mask film 310.

[0103] In Fig. 11, the mask film 310 may be etched using the photosensitive structure 325. Accordingly, a mask structure 315 may be formed on the substrate 300. The photosensitive structure 325 may be removed.

[0104] As one example, a portion of the substrate 300 may be etched using the mask structure 315. As another example, the mask structure 315 itself may be used as part of the semiconductor device.

Claims

[1] Extreme ultraviolet (EUV) mask blank (100) comprising: a substrate (110) having a first surface (110a); a reflective layer (120) having first reflective layers (121) and second reflective layers (122) alternately stacked on the first surface (110a) of the substrate (110); a cover layer (140) on the reflective layer (120); and a hydrogen absorber layer (130) between the reflective layer (120) and the cover layer (140), wherein the hydrogen absorber layer (130) contains a material having a lattice structure configured to dissolve hydrogen therein and is in contact with the cover layer (140), wherein the hydrogen absorber layer (130) comprises at least one of vanadium (V), manganese (Mn), iron (Fe), zirconium (Zr), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), cesium (Cs) or boron carbide (B 4 C). [2] The EUV mask blank (100) according to claim 1, wherein the hydrogen absorber layer (130) comprises a metal in which a change in the enthalpy of a hydrogen dissolution reaction is 0.5 (eV / absorbed hydrogen) or less. [3] The EUV mask blank (100) of claim 1, wherein the hydrogen absorber layer (130) is in contact with the reflective layer (120). [4] The EUV mask blank (100) of claim 1, further comprising an interface silicide layer (135) along an interface between the hydrogen absorber layer (130) and the reflective layer (120). [5] The EUV mask blank (100) of claim 4, wherein the hydrogen absorber layer (130) comprises a metal (M) and the interface silicide layer (135) comprises a silicide of the metal. [6] The EUV mask blank (100) of claim 1, wherein the first reflective layers (121) comprise silicon (Si) and the second reflective layer (122) is molybdenum (Mo). [7] The EUV mask blank (100) according to claim 1, wherein the cover layer (140) is a ruthenium (Ru) film or a ruthenium compound film. [8] The EUV mask blank (100) of claim 1, further comprising a light absorber layer (150) on the cover layer (140), wherein the light absorber layer (150) comprises a material configured to absorb extreme ultraviolet light. [9] The EUV mask blank (100) according to claim 1, further comprising a conductive coating film (160) on a second surface (110b) of the substrate (110) which is opposite to the first surface (110a). [10] Extreme ultraviolet (EUV) mask blank (100) comprising: a substrate (110) of a low thermal expansion material (LTEM) having a first surface (110a); a reflective layer (120) comprising a molybdenum (Mo) / silicon (Si) multilayer on the first surface (110a) of the LTEM substrate (110); a first absorber layer on the reflective layer (120), wherein the first absorber layer comprises at least one of vanadium (V), manganese (Mn), iron (Fe), zirconium (Zr), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), cesium (Cs) or boron carbide (B 4 C); a cover layer (140) on the first absorber layer, wherein the cover layer (140) comprises ruthenium (Ru) or a ruthenium compound; and a second absorber layer on the cover layer (140) opposite the first absorber layer. [11] The EUV mask blank (100) of claim 10, wherein the cover layer (140) is in contact with the first absorber layer. [12] The EUV mask blank (100) of claim 10, wherein the first absorber layer is in contact with the reflective layer (120). [13] The EUV mask blank (100) of claim 10, wherein the first absorber layer contains a transition metal, and further comprising an interface silicide layer (135) along an interface between the reflective layer (120) and the first absorber layer, wherein the interface silicide layer (135) comprises a silicide of the transition metal. [14] The EUV mask blank (100) of claim 10, wherein the first absorber layer comprises a material having a lattice structure configured to store hydrogen at interstitial sites thereof, and the second absorber layer comprises a material configured to absorb extreme ultraviolet light. [15] Photomask comprising: a substrate (110) having a first surface (110a) and a second surface (110b) opposite to each other; a reflective layer (120) comprising a molybdenum (Mo) / silicon (Si) multilayer on the first surface (110a) of the substrate (110); a cover layer (140) on the reflective layer (120); a hydrogen absorber layer (130) between the reflective layer (120) and the cover layer (140), the hydrogen absorber layer (130) being configured to store hydrogen and being in contact with the cover layer (140); a light absorption structure on the cover layer (140), the light absorption structure having an opening for the passage of extreme ultraviolet light therethrough; and a conductive coating film (160) on the second surface (110b) of the substrate (110), wherein the hydrogen absorber layer (130) comprises at least one of vanadium (V), manganese (Mn), iron (Fe), zirconium (Zr), hafnium (Hf), tantalum (Ta), rhodium (Rh), gold (Au), potassium (K), cesium (Cs) or boron carbide (B 4 C). [16] The photomask according to claim 15, wherein the hydrogen absorber layer (130) is in contact with the reflective layer (120) and comprises a material having a lattice structure configured to dissolve hydrogen therein, and wherein a change in the enthalpy of a hydrogen dissolution reaction in the hydrogen absorber layer (130) is 0.5 (eV / absorbed hydrogen) or less. [17] The photomask of claim 15, further comprising an interface silicide layer (135) along an interface between the hydrogen absorber layer (130) and the reflective layer (120).

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