Phase shift mask and method of manufacturing the same

Abstract

The application provides a phase shift mask and a manufacturing method thereof. The phase shift mask comprises: a light-transmitting substrate; a light-blocking layer, which is covered on the light-transmitting substrate to form a light-blocking area, the light-blocking layer is removed and stopped on the area of the surface of the light-transmitting substrate to form a light-transmitting area, the light-blocking layer is removed and the light-transmitting substrate below is partially removed to form a first phase shift area; a phase shift layer, which is covered on the light-transmitting area to form a second phase shift area and covered on the first phase shift area to form a third phase shift area, the phase shift layer makes the exposure light passing through the phase shift layer to produce phase conversion or / and light attenuation. The application can avoid the generation of "ghost line", so that the contrast and resolution of the photoresist pattern obtained by using the phase shift mask for exposure are greatly improved, and on the other hand, the function of the phase shift mask can be effectively widened, so that it can meet the needs of various application scenarios.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit manufacturing, and in particular relates to a phase-shifting mask and its fabrication method. Background Technology

[0002] With the continuous advancement of integrated circuit manufacturing methods and the shrinking linewidths, the area of ​​semiconductor devices is becoming increasingly smaller. Semiconductor layout has evolved from simple, single-function discrete devices to integrated, high-density, multi-functional integrated circuits. From the initial IC (Integrated Circuit), to LSI (Large-Scale Integration), VLSI (Very Large-Scale Integration), and finally to today's ULSI (Ultra-Large-Scale Integration), the device area has further decreased. Considering the complexity, long development time, and high cost of process development, how to further improve the integration density of devices based on existing technologies to obtain as many effective chips as possible on a single silicon wafer, thereby improving overall profitability, is receiving increasing attention from chip manufacturers. Photolithography plays a crucial role in this process, and for photolithography technology, photolithography equipment, processes, and mask technology are of paramount importance.

[0003] For photomasks, phase-shifting mask technology is one of the most practical techniques for improving lithography resolution. The principle of this technology is to reverse the phase of adjacent regions by 180 degrees so that the interference effects cancel each other out. This cancels out the negative impact of the optical proximity effect on the lithography quality of adjacent feature regions on the pattern as the linewidth continues to shrink. The key point of this technology is that the phase-shifting layer can precisely control the phase of the photomask pattern.

[0004] like Figure 1 As shown, a conventional phase-shifting mask includes a quartz substrate 11 and a chromium layer 12. After the chromium layer 12 on the phase-shifting mask is patterned, the phase shift is provided by the channel depth d on the quartz substrate 11.

[0005] like Figure 2 As shown, another type of phase-shifting mask includes a quartz substrate 21, a phase-shifting layer 23 and a chromium layer 22. After the chromium layer 22 and the phase-shifting layer 23 on the phase-shifting mask are patterned, the amount of phase shift and the amount of attenuation are determined by the thickness d of the phase-shifting layer 23.

[0006] For the two phase-shifting mask schemes mentioned above, there are positions with zero intensity due to the diffraction of transmitted light and 180° phase-shifted light. Although this can enhance the contrast of the image pattern, it may also cause "ghost lines" to appear on the positive photoresist pattern on the wafer, which is not conducive to the exposure accuracy of the positive photoresist.

[0007] To achieve better mask fabrication performance, phase-shifting masks can also contain multiple layers of materials. By controlling the thickness relationship between the multiple layers, regions with different phase-shifting angles can be formed on the mask, thereby avoiding "ghosting lines" on the positive photoresist pattern after exposure on the wafer. However, this approach has high requirements for the thickness of each layer and the process is very complex, which will significantly increase the cost of chip manufacturing. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a phase-shifting mask and its manufacturing method, so as to solve the problem that phase-shifting masks in the prior art are prone to ghosting lines or that the process difficulty and cost increase significantly in order to eliminate ghosting lines.

[0009] To achieve the above and other related objectives, the present invention provides a phase-shifting mask comprising: a light-transmitting substrate; a light-shielding layer covering the light-transmitting substrate to form a light-shielding region, wherein a region where the light-shielding layer is removed and stops at the surface of the light-transmitting substrate forms a light-transmitting region, and a region where the light-shielding layer is removed and the light-transmitting substrate below it is partially removed forms a first phase-shifting region; and a phase-shifting layer covering the light-transmitting region to form a second phase-shifting region and covering the first phase-shifting region to form a third phase-shifting region, wherein the phase-shifting layer causes phase transition and / or light attenuation of the exposure light transmitted through the phase-shifting layer.

[0010] Optionally, the material of the light-transmitting substrate includes quartz glass, and the material of the light-shielding layer includes chromium, chromium oxide, or chromium nitride.

[0011] Optionally, the material of the phase-shifting layer includes one of molybdenum oxide silicon, molybdenum oxynitride silicon, molybdenum oxynitride silicon carbide, chromium oxide silicon, chromium oxynitride silicon, and chromium oxynitride silicon carbide.

[0012] Optionally, the phase transition of the exposure light transmitted through the first phase-shifting region can be controlled by controlling the trench depth in the light-transmitting substrate in the first phase-shifting region.

[0013] Optionally, the phase conversion and / or light attenuation ratio of the exposed light transmitted through the phase shift layer can be controlled by controlling the thickness of the phase shift layer and its material composition.

[0014] Optionally, the phase-shifting layer causes the exposure light transmitted through it to undergo a phase transition by an amount between 0 and 180 degrees.

[0015] Optionally, the phase-shifting layer causes the light attenuation of the exposure light transmitted through the phase-shifting layer to be between 0% and 80%.

[0016] Optionally, the phase-shifting mask includes a plurality of the light-transmitting regions, and the phase-shifting layer covers a portion of the plurality of light-transmitting regions.

[0017] Optionally, the phase-shifting mask includes a plurality of first phase-shifting regions, and the phase-shifting layer covers a portion of the plurality of first phase-shifting regions.

[0018] The present invention also provides a method for manufacturing a phase-shifting mask, comprising the steps of: providing a light-transmitting substrate; depositing a light-shielding layer on the light-transmitting substrate; etching the light-shielding layer and stopping at the surface of the light-transmitting substrate to form a light-transmitting region; etching a portion of the light-transmitting region to form a trench in the light-transmitting substrate to form a first phase-shifting region; covering the light-transmitting region with a phase-shifting layer to form a second phase-shifting region and covering the first phase-shifting region with a phase-shifting layer to form a third phase-shifting region, wherein the phase-shifting layer causes phase conversion and / or light attenuation of the exposure light transmitted through the phase-shifting layer.

[0019] The present invention also provides a phase-shifting mask, the phase-shifting mask comprising: a light-transmitting substrate; a first phase-shifting layer covering the light-transmitting substrate to form a first phase-shifting region, wherein a region where the first phase-shifting layer is partially removed and stops at the surface of the light-transmitting substrate forms a light-transmitting region, and a region where the first phase-shifting layer is removed and the light-transmitting substrate below it is partially removed forms a second phase-shifting region, wherein the first phase-shifting layer causes phase shifting and / or light attenuation of the exposure light transmitted through the first phase-shifting layer; a second phase-shifting layer covering the light-transmitting region to form a third phase-shifting region, and covering the second phase-shifting region to form a fourth phase-shifting region, wherein the second phase-shifting layer covers a portion of the first phase-shifting region to form a light-shielding region, and causing phase shifting and / or light attenuation of the exposure light transmitted through the second phase-shifting layer.

[0020] Optionally, the material of the light-transmitting substrate includes quartz glass, and the materials of the first phase-shifting layer and the second phase-shifting layer include one of molybdenum oxide silicon, molybdenum oxynitride silicon, molybdenum oxynitride silicon carbide, chromium oxide silicon, chromium oxynitride silicon, and chromium oxynitride silicon carbide.

[0021] Optionally, the phase transition of the exposure light transmitted through the second phase-shifting region can be controlled by controlling the trench depth in the light-transmitting substrate in the second phase-shifting region.

[0022] Optionally, the first phase-shifting layer causes the exposure light transmitted through the first phase-shifting layer to undergo a phase transition of between 0 and 180 degrees, and the second phase-shifting layer causes the exposure light transmitted through the second phase-shifting layer to undergo a phase transition of between 0 and 180 degrees.

[0023] Optionally, the first phase shifting layer causes the light attenuation of the exposure light transmitted through the first phase shifting layer to be between 0% and 80%, and the second phase shifting layer causes the light attenuation of the exposure light transmitted through the second phase shifting layer to be between 0% and 80%.

[0024] Optionally, the phase-shifting mask includes a plurality of the light-transmitting regions, and the second phase-shifting layer covers a portion of the plurality of light-transmitting regions.

[0025] Optionally, the phase-shifting mask includes a plurality of second phase-shifting regions, and the second phase-shifting layer covers a portion of the plurality of second phase-shifting regions.

[0026] The present invention also provides a method for manufacturing a phase-shifting mask, comprising the steps of: providing a light-transmitting substrate; depositing a first phase-shifting layer on the light-transmitting substrate; etching the first phase-shifting layer and forming a light-transmitting region in the area where the first phase-shifting layer stops at the surface of the light-transmitting substrate; retaining the first phase-shifting layer to form a first phase-shifting region; the first phase-shifting layer causing phase transition and / or light attenuation of the exposure light transmitted through the first phase-shifting layer; etching a portion of the light-transmitting region to form a trench in the light-transmitting substrate to form a second phase-shifting region; forming a second phase-shifting layer; the second phase-shifting layer covering the light-transmitting region to form a third phase-shifting region; the second phase-shifting layer covering the second phase-shifting region to form a fourth phase-shifting region; the second phase-shifting layer covering a portion of the first phase-shifting region to form a light-shielding region; the second phase-shifting layer causing phase transition and / or light attenuation of the exposure light transmitted through the second phase-shifting layer.

[0027] As described above, the phase-shifting mask and its manufacturing method of the present invention have the following beneficial effects:

[0028] The phase-shifting mask of the present invention can form multiple regions with different phase shifts and attenuations, and the optical characteristics of each region can be controlled and adjusted to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask, so that it can meet the needs of various application scenarios. Attached Figure Description

[0029] Figure 1 The diagram shown is a schematic of a phase-shifting mask.

[0030] Figure 2 The diagram shows another type of phase-shifting mask and its mechanism.

[0031] Figures 3-6 The diagram shows the structural schematics of each step in the fabrication method of the phase-shifting mask in Embodiment 1 of the present invention, wherein... Figure 6 The diagram shown is a schematic diagram of the phase-shifting mask according to Embodiment 1 of the present invention.

[0032] Figures 7-10 The diagram shows the structural schematics of each step in the fabrication method of the phase-shifting mask in Embodiment 2 of the present invention, wherein... Figure 10 The diagram shown is a schematic diagram of the phase-shifting mask of Embodiment 2 of the present invention.

[0033] Component designation explanation

[0034] 101 Transparent substrate

[0035] 102 Light-shielding layer

[0036] 103 Shading Area

[0037] 104 Transparent Area

[0038] 105 First Phase Shift Region

[0039] 106 Second Phase Shift Region

[0040] 107 Third Phase Shift Region

[0041] 108 Phase Shifting Layer

[0042] 201 Transparent substrate

[0043] 202 First Phase Shifting Layer

[0044] 203 First Phase Shift Region

[0045] 204 Transparent Area

[0046] 205 Second Phase Shift Region

[0047] 206 Third Phase Shift Region

[0048] 207 Fourth Phase Shift Region

[0049] 208 Shading Area

[0050] 209 Second Phase Shifting Layer Detailed Implementation

[0051] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0052] In the detailed description of embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged and not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0053] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0054] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0055] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0056] Example 1

[0057] This embodiment provides a method for fabricating a phase-shifting mask, the method comprising the following steps:

[0058] like Figures 3-4 As shown, step 1) is performed first, a light-transmitting substrate 101 is provided, a light-shielding layer 102 is deposited on the light-transmitting substrate 101, and the light-shielding layer 102 is etched and stopped on the surface of the light-transmitting substrate 101 to form a light-transmitting region 104.

[0059] The light transmittance of the light-transmitting substrate 101 is preferably above 80%. In this embodiment, the material of the light-transmitting substrate 101 can be quartz glass, which has high light transmittance and can ensure the intensity of the exposure light transmitted through the light-transmitting substrate 101. Of course, in other embodiments, the light-transmitting substrate 101 can also be made of other materials with good light transmittance, and is not limited to the examples listed here.

[0060] For example, a light-shielding layer 102 can be deposited on the light-transmitting substrate 101 using methods such as magnetron sputtering. The material of the light-shielding layer 102 can be chromium, chromium oxide, or chromium nitride. Then, the light-shielding layer 102 can be etched using processes such as photolithography and etching, with the etching depth stopping at the surface of the light-transmitting substrate 101, to form a light-transmitting region 104, wherein the region blocked by the light-shielding layer 102 is the light-shielding region 103.

[0061] like Figure 5 As shown, then step 2) is performed, etching a portion of the light-transmitting area 104 to form a trench in the light-transmitting substrate 101 to form a first phase-shifting region 105.

[0062] For example, a portion of the light-transmitting area 104 that needs to be etched can be etched using photolithography and etching processes to form trenches in the light-transmitting substrate 101. By controlling the trench depth in the light-transmitting substrate 101 in the first phase-shifting region 105, the phase transition of the exposure light transmitted through the first phase-shifting region 105 can be controlled.

[0063] like Figure 6 As shown, in step 3), a phase-shifting layer 108 is covered in the light-transmitting region 104 to form a second phase-shifting region 106 and a phase-shifting layer 108 is covered in the first phase-shifting region 105 to form a third phase-shifting region 107. The phase-shifting layer 108 causes phase conversion and / or light attenuation of the exposure light transmitted through the phase-shifting layer 108.

[0064] Specifically, a phase-shifting layer 108 can be deposited on the light-transmitting substrate 101 using a process such as chemical vapor deposition or physical vapor deposition (e.g., magnetron sputtering). Then, the phase-shifting layer 108 in the areas where it is not necessary to deposit the phase-shifting layer 108 can be removed by photolithography and etching processes.

[0065] The material of the phase-shifting layer 108 includes one of molybdenum silicon oxide, molybdenum silicon oxynitride, molybdenum silicon carbide oxynitride, chromium silicon oxide, chromium silicon oxynitride, and chromium silicon carbide oxynitride. The phase-shifting layer 108 causes phase transition and / or light attenuation of the exposure light transmitted through it, wherein the components of the phase-shifting layer 108 can vary and determine the degree of phase transition and / or light attenuation.

[0066] By controlling the thickness and material composition of the phase shift layer 108, the phase transition and / or light attenuation ratio of the exposure light transmitted through the phase shift layer 108 can be controlled. Depending on the composition or structure of different phase shift layers 108, the amount of phase transition caused by the phase shift layer 108 is between 0 and 180 degrees, for example, 90 degrees, 180 degrees, etc. The light attenuation ratio of the exposure light transmitted through the phase shift layer 108 is between 0 and 80%, for example, 20%, 30%, 50%, 60%, etc.

[0067] In this embodiment, as Figure 6 As shown, the phase-shifting mask includes a plurality of light-transmitting regions 104, and the phase-shifting layer 108 covers a portion of the plurality of light-transmitting regions 104. The phase-shifting mask also includes a plurality of first phase-shifting regions, and the phase-shifting layer 108 covers a portion of the plurality of first phase-shifting regions.

[0068] Specifically, such as Figure 6 As shown, this embodiment can form multiple regions with different phase transition and / or light attenuation properties, including a light-transmitting region 104, a light-shielding region 103, a first phase-shifting region 105, a second phase-shifting region 106, and a third phase-shifting region 107; wherein, the light-shielding region 103 includes a light-shielding layer 102, the light-transmitting region 104 is the exposed surface of the light-transmitting substrate 101, the first phase-shifting region 105 is a trench in the light-transmitting substrate 101, the second phase-shifting region 106 is a phase-shifting layer 108 covering the light-transmitting substrate 101, and the third phase-shifting region 107... The phase-shifting region 107 is a trench in the light-transmitting substrate 101 and a phase-shifting layer 108 covering the inner surface of the trench. Each of these regions has a different structure, which can control and adjust the optical characteristics of each region to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask so that it can meet the needs of various application scenarios.

[0069] like Figure 6As shown, this embodiment also provides a phase-shifting mask, which includes: a light-transmitting substrate 101; a light-shielding layer 102 covering the light-transmitting substrate 101 to form a light-shielding region 103, wherein the area where the light-shielding layer 102 is removed and stops on the surface of the light-transmitting substrate 101 forms a light-transmitting region 104, and the area where the light-shielding layer 102 is removed and the light-transmitting substrate 101 below it is partially removed forms a first phase-shifting region 105; and a phase-shifting layer 108 covering the light-transmitting region 104 to form a second phase-shifting region 106 and covering the first phase-shifting region 105 to form a third phase-shifting region 107, wherein the phase-shifting layer 108 causes phase conversion and / or light attenuation of the exposure light transmitted through the phase-shifting layer 108.

[0070] The light transmittance of the light-transmitting substrate 101 is preferably above 80%. In this embodiment, the material of the light-transmitting substrate 101 can be quartz glass, which has high light transmittance and can ensure the intensity of the exposure light transmitted through the light-transmitting substrate 101. Of course, in other embodiments, the light-transmitting substrate 101 can also be made of other materials with good light transmittance, and is not limited to the examples listed here.

[0071] The material of the light-shielding layer 102 includes chromium, chromium oxide, or chromium nitride.

[0072] like Figure 6 As shown, by controlling the trench depth in the light-transmitting substrate 101 in the first phase-shifting region 105, the phase transition of the exposure light transmitted through the first phase-shifting region 105 can be controlled.

[0073] The material of the phase-shifting layer 108 includes one of molybdenum silicon oxide, molybdenum silicon oxynitride, molybdenum silicon carbide oxynitride, chromium silicon oxide, chromium silicon oxynitride, and chromium silicon carbide oxynitride. The phase-shifting layer 108 causes phase transition and / or light attenuation of the exposure light transmitted through it, wherein the components of the phase-shifting layer 108 can vary and determine the degree of phase transition and / or light attenuation.

[0074] In this embodiment, the phase transition and / or light attenuation ratio of the exposure light transmitted through the phase shift layer 108 can be controlled by controlling the thickness and material composition of the phase shift layer 108. Depending on the composition or structure of different phase shift layers 108, the change in phase transition of the exposure light transmitted through the phase shift layer 108 is between 0 and 180 degrees, for example, 90 degrees, 180 degrees, etc. The light attenuation ratio of the exposure light transmitted through the phase shift layer 108 is between 0 and 80%, for example, 20%, 30%, 50%, 60%, etc.

[0075] In this embodiment, as Figure 6As shown, the phase-shifting mask includes a plurality of light-transmitting regions 104, and the phase-shifting layer 108 covers a portion of the plurality of light-transmitting regions 104. The phase-shifting mask also includes a plurality of first phase-shifting regions, and the phase-shifting layer 108 covers a portion of the plurality of first phase-shifting regions.

[0076] Specifically, such as Figure 6 As shown, this embodiment can form multiple regions with different phase transition and / or light attenuation properties, including a light-transmitting region 104, a light-shielding region 103, a first phase-shifting region 105, a second phase-shifting region 106, and a third phase-shifting region 107; wherein, the light-shielding region 103 includes a light-shielding layer 102, the light-transmitting region 104 is the exposed surface of the light-transmitting substrate 101, the first phase-shifting region 105 is a trench in the light-transmitting substrate 101, the second phase-shifting region 106 is a phase-shifting layer 108 covering the light-transmitting substrate 101, and the third phase-shifting region 107... The phase-shifting region 107 is a trench in the light-transmitting substrate 101 and a phase-shifting layer 108 covering the inner surface of the trench. Each of these regions has a different structure, which can control and adjust the optical characteristics of each region to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask so that it can meet the needs of various application scenarios.

[0077] Example 2

[0078] like Figures 7-10 As shown, this embodiment provides a method for fabricating a phase-shifting mask, the method comprising the following steps:

[0079] like Figures 7-8 As shown, step 1) is performed first, a light-transmitting substrate 201 is provided, a first phase-shifting layer 202 is deposited on the light-transmitting substrate 201, the first phase-shifting layer 202 is etched and the area where it stops on the surface of the light-transmitting substrate 201 is formed to form a light-transmitting region 204, the retained first phase-shifting layer 202 forms a first phase-shifting region 203, and the first phase-shifting layer 202 causes the exposure light transmitted through the first phase-shifting layer 202 to undergo phase conversion and / or light attenuation.

[0080] For example, the light transmittance of the light-transmitting substrate 201 is preferably 80% or higher. In this embodiment, the material of the light-transmitting substrate 201 can be quartz glass, which has high light transmittance and can ensure the intensity of the exposure light transmitted through the light-transmitting substrate 201. Of course, in other embodiments, the light-transmitting substrate 201 can also be made of other materials with good light transmittance, and is not limited to the examples listed here.

[0081] For example, the first phase-shifting layer 202 can be deposited on the light-transmitting substrate 201 using methods such as magnetron sputtering. Then, photolithography and etching processes are used to etch the first phase-shifting layer 202, forming a light-transmitting region 204 at the area stopping on the surface of the light-transmitting substrate 201. The remaining first phase-shifting layer 202 forms the first phase-shifting region 203. The first phase-shifting layer 202 causes phase transitions and / or light attenuation in the exposure light transmitted through it. The material of the first phase-shifting layer 202 includes one of molybdenum silicon oxide, molybdenum silicon oxynitride, molybdenum silicon oxynitride, chromium silicon oxide, chromium silicon oxynitride, and chromium silicon oxynitride, wherein each component can vary and determine the degree of phase transition and / or light attenuation. By controlling the thickness of the first phase-shifting layer 202, different phase transitions of the exposure light can be achieved. For example, the first phase shifting layer 202 causes the exposure light transmitted through the first phase shifting layer 202 to undergo a phase shift change of between 0 and 180 degrees, and the first phase shifting layer 202 causes the exposure light transmitted through the first phase shifting layer 202 to undergo a light attenuation of between 0 and 80%.

[0082] like Figure 9 As shown, then step 2) is performed, etching a portion of the light-transmitting region 204 to form a trench in the light-transmitting substrate 201 to form a second phase-shifting region 205.

[0083] For example, a portion of the light-transmitting area 204 that needs to be etched can be etched using photolithography and etching processes to form trenches in the light-transmitting substrate 201, thereby forming a second phase-shifting region 205. By controlling the trench depth in the light-transmitting substrate 201 within the second phase-shifting region 205, the phase transition of the exposure light transmitted through the second phase-shifting region 205 can be controlled.

[0084] like Figure 10 As shown, step 3) is performed last to form a second phase-shifting layer 209. The second phase-shifting layer 209 covers the light-transmitting area 204 to form a third phase-shifting area 206. The second phase-shifting layer 209 covers the second phase-shifting area 205 to form a fourth phase-shifting area 207. The second phase-shifting layer 209 covers a portion of the first phase-shifting area 203 to form a light-shielding area 208. The second phase-shifting layer 209 causes phase conversion and / or light attenuation of the exposure light transmitted through the second phase-shifting layer 209.

[0085] Specifically, a second phase-shifting layer 209 can be deposited on the light-transmitting substrate 201 using a process such as chemical vapor deposition or physical vapor deposition (e.g., magnetron sputtering). Then, the second phase-shifting layer 209 in the areas where it is not necessary to deposit the second phase-shifting layer 209 can be removed by photolithography and etching processes.

[0086] The material of the second phase-shifting layer 209 includes one of molybdenum silicon oxide, molybdenum silicon oxynitride, molybdenum silicon carbide oxynitride, chromium silicon oxide, chromium silicon oxynitride, and chromium silicon carbide oxynitride. The second phase-shifting layer 209 causes phase transition and / or light attenuation of the exposure light transmitted through it, wherein the components of the second phase-shifting layer 209 can vary and determine the degree of phase transition and / or light attenuation.

[0087] By controlling the thickness and material composition of the second phase-shifting layer 209, the phase transition and / or light attenuation ratio of the exposure light transmitted through the second phase-shifting layer 209 can be controlled. Depending on the different compositions or structures of the second phase-shifting layer 209, the amount of phase transition caused by the second phase-shifting layer 209 is between 0 and 180 degrees, for example, 90 degrees, 180 degrees, etc. The light attenuation ratio of the exposure light transmitted through the second phase-shifting layer 209 is between 0 and 80%, for example, 20%, 30%, 50%, 60%, etc.

[0088] In this embodiment, as Figure 10 As shown, the phase-shifting mask includes a plurality of light-transmitting regions 204, and the second phase-shifting layer 209 covers a portion of the plurality of light-transmitting regions 204. The phase-shifting mask also includes a plurality of second phase-shifting regions 205, and the second phase-shifting layer 209 covers a portion of the plurality of second phase-shifting regions 205. Simultaneously, the second phase-shifting layer 209 covers a portion of the first phase-shifting region 203 to form a light-blocking region 208. Specifically, by controlling the phase transition and / or light attenuation between the second phase-shifting layer 209 and the first phase-shifting layer 202, the overlapping second phase-shifting layer 209 and the first phase-shifting layer 202 become opaque.

[0089] Specifically, such as Figure 10As shown, this embodiment can form multiple regions with different phase transition and / or light attenuation properties, including a light-transmitting region 204, a light-blocking region 208, a first phase-shifting region 203, a second phase-shifting region 205, a third phase-shifting region 206, and a fourth phase-shifting region 207; wherein, the light-blocking region 208 includes overlapping first phase-shifting layers 202 and second phase-shifting layers 209, the light-transmitting region 204 is the exposed surface of the light-transmitting substrate 201, the first phase-shifting region 203 is a single layer of the first phase-shifting layer 202, the second phase-shifting region 205 is a trench in the light-transmitting substrate 201, and the third phase-shifting region 206 is... A second phase-shifting layer 209 is covered on the light-transmitting substrate 201. The fourth phase-shifting region 207 is a trench in the light-transmitting substrate 201 and the second phase-shifting layer 209 covering the inner surface of the trench. Each of the above regions has a different structure, which can control and adjust the optical characteristics of each region to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask so that it can meet the needs of various application scenarios.

[0090] like Figure 10 As shown, this embodiment also provides a phase-shifting mask, which includes: a light-transmitting substrate 201; a first phase-shifting layer 202 covering the light-transmitting substrate 201 to form a first phase-shifting region 203; a region where the first phase-shifting layer 202 is partially removed and stops at the surface of the light-transmitting substrate 201 to form a light-transmitting region 204; and a region where the first phase-shifting layer 202 is removed and the light-transmitting substrate 201 below it is partially removed to form a second phase-shifting region 205. The first phase-shifting layer 202 allows light to pass through the first phase-shifting layer. The exposed light in layer 202 undergoes phase shift and / or light attenuation; a second phase-shifting layer 209 covers the light-transmitting area 204 to form a third phase-shifting area 206, the second phase-shifting layer 209 covers the second phase-shifting area 205 to form a fourth phase-shifting area 207, the second phase-shifting layer 209 covers a portion of the first phase-shifting area 203 to form a light-shielding area 208, and the second phase-shifting layer 209 causes the exposed light transmitted through the second phase-shifting layer 209 to undergo phase shift and / or light attenuation.

[0091] The light transmittance of the light-transmitting substrate 201 is preferably above 80%. In this embodiment, the material of the light-transmitting substrate 201 can be quartz glass, which has high light transmittance and can ensure the intensity of the exposure light transmitted through the light-transmitting substrate 201. Of course, in other embodiments, the light-transmitting substrate 201 can also be made of other materials with good light transmittance, and is not limited to the examples listed here.

[0092] The first phase-shifting layer 202 causes phase transition and / or light attenuation of the exposure light transmitted through it. The material of the first phase-shifting layer 202 includes one of molybdenum oxide silicon, molybdenum oxynitride silicon, molybdenum oxynitride silicon carbide, chromium oxide silicon, chromium oxynitride silicon, and chromium oxynitride silicon carbide, wherein each component can vary and determine the degree of phase transition and / or light attenuation. By controlling the thickness of the first phase-shifting layer 202, different phase transitions of the exposure light can be achieved. For example, the amount of phase transition caused by the first phase-shifting layer 202 is between 0 and 180 degrees, and the proportion of light attenuation caused by the first phase-shifting layer 202 is between 0 and 80%.

[0093] By controlling the trench depth in the light-transmitting substrate 201 in the second phase-shifting region 205, the phase transition of the exposure light transmitted through the second phase-shifting region 205 can be controlled.

[0094] The material of the second phase-shifting layer 209 includes one of molybdenum silicon oxide, molybdenum silicon oxynitride, molybdenum silicon carbide oxynitride, chromium silicon oxide, chromium silicon oxynitride, and chromium silicon carbide oxynitride. The second phase-shifting layer 209 causes phase transition and / or light attenuation of the exposure light transmitted through it, wherein the components of the second phase-shifting layer 209 can vary and determine the degree of phase transition and / or light attenuation.

[0095] By controlling the thickness and material composition of the second phase-shifting layer 209, the phase transition and / or light attenuation ratio of the exposure light transmitted through the second phase-shifting layer 209 can be controlled. Depending on the different compositions or structures of the second phase-shifting layer 209, the amount of phase transition caused by the second phase-shifting layer 209 is between 0 and 180 degrees, for example, 90 degrees, 180 degrees, etc. The light attenuation ratio of the exposure light transmitted through the second phase-shifting layer 209 is between 0 and 80%, for example, 20%, 30%, 50%, 60%, etc.

[0096] In this embodiment, as Figure 10As shown, the phase-shifting mask includes a plurality of light-transmitting regions 204, and the second phase-shifting layer 209 covers a portion of the plurality of light-transmitting regions 204. The phase-shifting mask also includes a plurality of second phase-shifting regions 205, and the second phase-shifting layer 209 covers a portion of the plurality of second phase-shifting regions 205. Simultaneously, the second phase-shifting layer 209 covers a portion of the first phase-shifting region 203 to form a light-blocking region 208. Specifically, by controlling the phase transition and / or light attenuation between the second phase-shifting layer 209 and the first phase-shifting layer 202, the overlapping second phase-shifting layer 209 and the first phase-shifting layer 202 become opaque.

[0097] Specifically, such as Figure 10 As shown, this embodiment can form multiple regions with different phase transition and / or light attenuation properties, including a light-transmitting region 204, a light-blocking region 208, a first phase-shifting region 203, a second phase-shifting region 205, a third phase-shifting region 206, and a fourth phase-shifting region 207; wherein, the light-blocking region 208 includes overlapping first phase-shifting layers 202 and second phase-shifting layers 209, the light-transmitting region 204 is the exposed surface of the light-transmitting substrate 201, the first phase-shifting region 203 is a single layer of the first phase-shifting layer 202, the second phase-shifting region 205 is a trench in the light-transmitting substrate 201, and the third phase-shifting region 206 is... A second phase-shifting layer 209 is covered on the light-transmitting substrate 201. The fourth phase-shifting region 207 is a trench in the light-transmitting substrate 201 and the second phase-shifting layer 209 covering the inner surface of the trench. Each of the above regions has a different structure, which can control and adjust the optical characteristics of each region to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask so that it can meet the needs of various application scenarios.

[0098] As described above, the phase-shifting mask and its manufacturing method of the present invention have the following beneficial effects:

[0099] The phase-shifting mask of the present invention can form multiple regions with different phase shifts and attenuations, and the optical characteristics of each region can be controlled and adjusted to produce different degrees of phase shift and attenuation of the exposed light. On the one hand, it can avoid the generation of "ghost lines", thereby greatly improving the contrast and resolution of the photoresist pattern exposed by the phase-shifting mask. On the other hand, it can effectively broaden the function of the phase-shifting mask, so that it can meet the needs of various application scenarios.

[0100] Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0101] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A phase-shifting mask, characterized in that, The phase-shifting mask includes: Transparent substrate; A light-shielding layer is applied to the light-transmitting substrate to form a light-shielding area. The area where the light-shielding layer is removed and stops on the surface of the light-transmitting substrate forms a light-transmitting area. The area where the light-shielding layer is removed and the light-transmitting substrate below it is partially removed forms a first phase-shifting area. A phase-shifting layer covers the light-transmitting area to form a second phase-shifting area and covers the first phase-shifting area to form a third phase-shifting area. The phase-shifting layer causes phase shifting and / or light attenuation of the exposed light transmitted through it. The light-transmitting area, the first phase-shifting area, the second phase-shifting area, and the third phase-shifting area have different structures to control and adjust the optical characteristics of each area to produce different degrees of phase shifting and attenuation of the exposed light. The amount of phase shifting caused by the phase-shifting layer is between 0 and 180 degrees. The proportion of light attenuation caused by the phase-shifting layer is between 0 and 80%.

2. The phase-shifting mask according to claim 1, characterized in that: The material of the light-transmitting substrate includes quartz glass, and the material of the light-shielding layer includes chromium, chromium oxide, or chromium nitride.

3. The phase-shifting mask according to claim 1, characterized in that: The material of the phase-shifting layer includes one of molybdenum oxide silicon, molybdenum oxynitride silicon, molybdenum oxynitride silicon carbide, chromium oxide silicon, chromium oxynitride silicon, and chromium oxynitride silicon carbide.

4. The phase-shifting mask according to claim 1, characterized in that: The phase transition of the exposure light transmitted through the first phase-shifting region is controlled by controlling the trench depth in the light-transmitting substrate in the first phase-shifting region.

5. The phase-shifting mask according to claim 1, characterized in that: By controlling the thickness and material composition of the phase-shifting layer, the phase conversion and / or light attenuation ratio of the exposed light transmitted through the phase-shifting layer can be controlled.

6. The phase-shifting mask according to claim 1, characterized in that: The phase-shifting mask includes a plurality of light-transmitting regions, and the phase-shifting layer covers a portion of the plurality of light-transmitting regions.

7. The phase-shifting mask according to claim 1 or 6, characterized in that: The phase-shifting mask includes a plurality of first phase-shifting regions, and the phase-shifting layer covers a portion of the plurality of first phase-shifting regions.

8. A method for manufacturing a phase-shifting mask as described in any one of claims 1 to 7, characterized in that, Including the following steps: A light-transmitting substrate is provided, a light-shielding layer is deposited on the light-transmitting substrate, and the light-shielding layer is etched and stopped on the surface of the light-transmitting substrate to form a light-transmitting area; The light-transmitting area is etched to form trenches in the light-transmitting substrate to form a first phase-shifting region; A phase-shifting layer is covered in the light-transmitting area to form a second phase-shifting area, and a phase-shifting layer is covered in the first phase-shifting area to form a third phase-shifting area. The phase-shifting layer causes phase shifting and / or light attenuation of the exposed light transmitted through the phase-shifting layer. The light-transmitting area, the first phase-shifting area, the second phase-shifting area, and the third phase-shifting area have different structures to control and adjust the optical characteristics of each area so that they produce different degrees of phase shifting and attenuation of the exposed light.

9. A phase-shifting mask, characterized in that, The phase-shifting mask includes: Transparent substrate; A first phase-shifting layer is applied to the light-transmitting substrate to form a first phase-shifting region. The area where the first phase-shifting layer is partially removed and stops on the surface of the light-transmitting substrate forms a light-transmitting region. The area where the first phase-shifting layer is removed and the light-transmitting substrate below it is partially removed forms a second phase-shifting region. The first phase-shifting layer causes phase conversion and / or light attenuation of the exposure light transmitted through the first phase-shifting layer. A second phase-shifting layer covers the light-transmitting area to form a third phase-shifting area, and the second phase-shifting layer covers the second phase-shifting area to form a fourth phase-shifting area. The second phase-shifting layer partially covers the first phase-shifting area to form a light-shielding area. The second phase-shifting layer causes phase shifting and / or light attenuation of the exposed light transmitted through it. The light-transmitting area, the first phase-shifting area, the second phase-shifting area, the third phase-shifting area, and the fourth phase-shifting area have different structures to control and adjust the optical characteristics of each area to produce different degrees of phase shifting and attenuation of the exposed light. The change in phase shift caused by the first phase-shifting layer is between 0 and 180 degrees, and the change in phase shift caused by the second phase-shifting layer is between 0 and 180 degrees. The proportion of light attenuation caused by the first phase-shifting layer is between 0 and 80%, and the proportion of light attenuation caused by the second phase-shifting layer is between 0 and 80%.

10. The phase-shifting mask according to claim 9, characterized in that: The material of the light-transmitting substrate includes quartz glass, and the materials of the first phase-shifting layer and the second phase-shifting layer include one of molybdenum oxide silicon, molybdenum oxynitride silicon, molybdenum oxynitride silicon carbide, chromium oxide silicon, chromium oxynitride silicon, and chromium oxynitride silicon carbide.

11. The phase-shifting mask according to claim 9, characterized in that: The phase transition of the exposure light transmitted through the second phase-shifting region is controlled by controlling the trench depth in the light-transmitting substrate in the second phase-shifting region.

12. The phase-shifting mask according to claim 9, characterized in that: The phase-shifting mask includes a plurality of light-transmitting regions, and the second phase-shifting layer covers a portion of the plurality of light-transmitting regions.

13. The phase-shifting mask according to claim 9 or 12, characterized in that: The phase-shifting mask includes a plurality of second phase-shifting regions, and the second phase-shifting layer covers a portion of the plurality of second phase-shifting regions.

14. A method for manufacturing a phase-shifting mask as described in any one of claims 9 to 13, characterized in that, Including the following steps: A light-transmitting substrate is provided, a first phase-shifting layer is deposited on the light-transmitting substrate, the first phase-shifting layer is etched and the area where it stops on the surface of the light-transmitting substrate forms a light-transmitting region, the retained first phase-shifting layer forms a first phase-shifting region, and the first phase-shifting layer causes phase conversion and / or light attenuation of the exposed light transmitted through the first phase-shifting layer; The light-transmitting area is etched to form trenches in the light-transmitting substrate to form a second phase-shifting region; A second phase-shifting layer is formed, which covers the light-transmitting area to form a third phase-shifting area. The second phase-shifting layer covers the second phase-shifting area to form a fourth phase-shifting area. The second phase-shifting layer covers a portion of the first phase-shifting area to form a light-shielding area. The second phase-shifting layer causes phase shifting and / or light attenuation of the exposed light transmitted through it. The light-transmitting area, the first phase-shifting area, the second phase-shifting area, the third phase-shifting area, and the fourth phase-shifting area have different structures to control and adjust the optical characteristics of each area so that they produce different degrees of phase shifting and attenuation of the exposed light.

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