Lithographic apparatus, patterning system and method for patterning layered structures

Abstract

Embodiments of the invention include a lithographic apparatus, patterning system and method for patterning a layered structure. The patterning system includes an image forming device and a reaction layer. The patterning system allows the creation of a lithographic pattern in a single operation. A lithographic apparatus includes a patterning system and an optical system. A lithographic apparatus uses light of multiple wavelengths with an image forming device to create multiple color patterns on a reactive layer. The patterning method includes exposing the reactive layer to light of a plurality of wavelengths. According to the wavelength of the light emitted to the different areas, the light can react with the different areas of the reaction layer differently. The methods and apparatus disclosed herein require only one image forming device and one lithographic operation.

Description

[0001] This invention application is a divisional application of the invention patent application with application number 202080076833.X, application date November 18, 2020, and name “Photolithography equipment, patterning system and method for patterned layered structure”. Technical Field

[0002] Embodiments of the present disclosure relate to an apparatus and method, and more particularly, to a lithographic apparatus, patterning system, and method for patterning layered structures.

[0003] Description of the Prior Art

[0004] Photolithography plays a vital role in the fabrication of integrated circuit (IC) chips. Continuous improvements in optical projection lithography technology have enabled the printing of finer integrated circuit features. This, in turn, has enabled the IC industry to produce more powerful and cost-effective semiconductor devices.

[0005] In the field of optical lithography, a photosensitive material is applied to a substrate and then dried. An exposure tool exposes the photosensitive material-coated substrate in an appropriate geometric pattern through a mask using a light source or radiation source. After exposure, the wafer is processed to develop the mask image transferred to the photosensitive material. These mask patterns are then used to form the device features of the circuit.

[0006] When the pattern resolution requirements for a single design layer exceed the capabilities of the exposure tool, these limitations can be addressed by splitting the patterning into multiple photolithography passes. However, many photolithography patterns use multiple masks across multiple steps. This requires acquiring the substrate and adding a second mask after the first patterning, slowing the photolithography process and increasing user costs. Furthermore, the second mask placement step requires careful alignment. Misalignment errors can result in misaligned patterns, wasting resources and requiring additional time to correct.

[0007] Therefore, improved photolithographic methods are needed, and reducing the number of patterning steps required would be valuable. Summary of the Invention

[0008] Embodiments of the present invention include lithographic apparatus, patterning systems, and methods for patterning layered structures. The apparatus and methods provided herein can perform enhanced-resolution lithographic processes in a single lithographic operation, eliminating the need for multiple photoresist applications, development steps, etching processes, or the need for multiple masks.

[0009] In one embodiment, a photolithography apparatus is provided, comprising: a substrate support configured to support a layered structure; a light source system capable of emitting light of two or more wavelengths; and an image forming device capable of receiving light of two or more wavelengths generated by the light source system and generating two or more light images at the two or more wavelengths received from the light source system.

[0010] In another embodiment, a patterning system is provided, comprising an image forming device and a photosensitive reactive layer. The reactive material comprises a first region and a second region. The image forming device is configured to allow light of a first wavelength to reach the first region, and the image forming device is configured to allow light of a second wavelength to reach the second region.

[0011] In yet another embodiment, a method for patterning a layered structure is provided, comprising the steps of: disposing a reactive layer on the layered structure; and exposing the reactive layer to light of multiple wavelengths using an image forming device. The reactive layer comprises a reactive material. The reactive material comprises a first region and a second region. Exposing the reactive layer comprises exposing the first region to light of a first wavelength and exposing the second region to light of a second wavelength. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Thus, the manner in which the above-described features of the present invention may be understood in detail, the present invention will be described in more detail by reference to the embodiments, the detailed description of which is briefly described above, and some embodiments of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of the scope, as other equally effective embodiments may be admitted.

[0013] Figure 1 The diagram illustrates a lithographic apparatus according to one or more embodiments described and discussed herein.

[0014] Figure 2 is a flow chart illustrating method operations for patterning a layered structure in accordance with one or more embodiments described and discussed herein.

[0015] Figure 3A The figure illustrates a top view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0016] Figure 3B The figure illustrates a cross-sectional side view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0017] Figure 3C The figure illustrates a top view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0018] Figure 3DThe figure illustrates a cross-sectional side view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0019] Figure 3E The figure illustrates a top view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0020] Figure 3F The figure illustrates a cross-sectional side view of a portion of a reaction layer according to one or more embodiments described and discussed herein.

[0021] Figures 4A to 4C The diagram illustrates light having a first wavelength incident on a reactive layer according to one or more embodiments described and discussed herein.

[0022] Figures 5A-5B The figure illustrates a cross-sectional side view of a portion of a workpiece including a reacted layer at various stages of processing according to one or more embodiments described and discussed herein.

[0023] Figure 5C The diagram shows a schematic diagram of a device according to one or more embodiments described and discussed herein. Figure 5B A top view of a portion of the workpiece.

[0024] Figure 6 The figure illustrates a top view of a portion of a workpiece including a reacted layer at a processing stage according to one or more embodiments described and discussed herein.

[0025] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0026] Embodiments of the present invention include a photolithography apparatus, a patterning system, and a method for patterning a layered structure. The patterning system includes a multi-wavelength light source, an image forming device, and a reaction layer, the reaction layer having multiple behaviors corresponding to light of multiple wavelengths. The patterning system allows two or more different photolithography patterns to be created at two or more different wavelengths. The photolithography apparatus includes a patterning system and an optical system. The photolithography apparatus uses multiple wavelengths of light that can be discretely guided by the image forming device to form multiple patterns and / or images on the reaction layer. The patterning method includes exposing the reaction layer to light of multiple wavelengths. Light of different wavelengths is exposed to different areas of the reaction layer. Different areas of the reaction layer react differently depending on the wavelength of the exposed light. The methods and apparatus disclosed in the present invention require only one photolithography operation. In addition, the use of a single illumination operation reduces the need to align multiple masks in multiple steps, thereby reducing photolithography time. Embodiments of the present invention can be used for, but are not limited to, a photolithography apparatus configured to provide light of multiple wavelengths to two different parts of a reaction layer.

[0027] Figure 1 The figure shows a lithographic apparatus 100 according to one or more embodiments described and discussed herein. The lithographic apparatus 100 is configured to transmit multiple images of different wavelengths onto an underlying layered structure 117. The lithographic apparatus 100 can be any lithographic tool used in the art, such as, but not limited to, a mask-based lithographic tool, or a maskless (direct write) lithographic tool with a multi-beam array architecture or a grating beam architecture.

[0028] As shown, the lithographic apparatus 100 includes an optical system 103, a patterning system 150, a substrate support 116, and a controller 190. The substrate support 116 is configured to support a layered structure 117. The substrate support 116 is attached to a support actuator 118. The support actuator 118 is configured to move the substrate support 116 to any position in three-dimensional space. For example, the substrate support 116 can be lowered to receive the layered structure 117 from a robot (not shown) outside the lithographic apparatus 100.

[0029] Layered structure 117 is used as a workpiece for various semiconductor devices, printed circuit boards, flat panel displays, and / or other MEMS, optical devices, and the like. As shown, layered structure 117 includes substrate 115. Substrate 115 can be any substrate used in the art. For example, substrate 115 includes a semiconductor material such as silicon (Si), germanium (Ge), silicon germanium (SiGe), and / or a III-V semiconductor such as gallium arsenide (GaAs). In another example, substrate 115 includes a transparent material such as glass and / or plastic. Substrate 115 can have any number of insulating layers, semiconductor layers, or metal layers on substrate 115.

[0030] The optical system 103 is configured to emit and control multiple discrete wavelength images of light onto the underlying layered structure 117. As shown, the optical system 103 includes one or more projection lenses 105 and a light source system 130. The light source system 130 is configured to emit light of multiple wavelengths, for example, two wavelengths. The wavelengths emitted by the light source system can be any wavelength in the electromagnetic system, such as ultraviolet (UV), visible light, or infrared (IR). According to one or more embodiments described and discussed herein, the light source system emits light having a first wavelength of about 240 nm to about 250 nm (e.g., deep ultraviolet (DUV) light) and light having a second wavelength of about 300 nm to about 375 nm (e.g., UV or i-ray light). The wavelength of the light is selected by one skilled in the art based on the photosensitive reactants within the reaction layer, as described in more detail below.

[0031] The light source system 130 may include a single light source or a plurality of light sources, for example, a first light source and a second light source. According to one or more embodiments described and discussed herein, the first and second light sources are configured to emit light of a first and a second wavelength. According to one or more embodiments described and discussed herein, the light source system 130 includes a single light source that sequentially emits light of these wavelengths. The light source may be any light source used in the art, such as a light emitting diode (LED), a laser diode, a vertical cavity surface emitting laser diode (VCSEL), an excimer laser (such as a krypton fluoride (KrF) or argon fluoride (ArF) laser), a frequency-doubled laser (such as a neodymium-doped yttrium aluminum garnet (Nd:Y3A) laser with a frequency of 1.06 μm), a laser diode (such as a laser diode ... l5 O 12 )[Nd:YAG] laser), with a frequency three times that of 353 nm, or four times that of 266 nm, a conventional mercury halide lamp with a bandpass filter alternating between about 365 nm and about 405 nm, or other light source combinations that match the behavior of the various photosensitive reactants within the reaction layer.

[0032] The one or more projection lenses 105 can be any projection lens used in the art (e.g., spherical, cylindrical), and can include any suitable layers or coatings on the one or more projection lenses 105. The optical system 103 can further include a beam splitter (not shown) to focus the light source system 130 onto the patterning system 150 below. According to one or more embodiments described and discussed herein, the beam splitter focuses light emitted from multiple light sources onto a single projection lens, and the projection lens focuses the light onto the patterning system 150. According to one or more embodiments described and discussed herein, light emitted from multiple light sources is focused by the one or more projection lenses 105, and the projection lens focuses the light onto the patterning system 150.

[0033] The patterning system 150 is configured to pattern a desired pattern onto the layered structure 117. As shown, the patterning system 150 includes an image forming device 120 and a reactive layer 110. The image forming device 120 can be any device used in the art for photolithography. The image forming device 120 is configured to allow light to pass through a predetermined area. The image forming device 120 can include any mask used in the art for photolithography, such as a photomask, a virtual mask, and / or a digital mask (e.g., a spatial light modulator such as a digital micromirror device (DMD)). The image forming device 120 can include any number of masks or a combination of masks, such as one mask or two photomasks having two different color blocking patterns.

[0034] The image forming device 120 is operable to receive two or more wavelengths of light generated by the light source system 130 and generate two or more light images having the two or more received wavelengths. The image forming device 120 may include any number of regions, and each region is configured to allow light to be incident on a specific portion of the reactive layer 110. In some embodiments, the image forming device 120 includes multiple photomasks, and each photomask is configured to receive light of a different wavelength. In some embodiments, the image forming device 120 includes a multi-color mask, and the multi-color mask absorbs certain wavelengths at certain portions of the mask while allowing other wavelengths to be transmitted at the same portions of the mask. In some embodiments, the image forming device 120 includes multiple photomask layers, and each photomask layer is configured to transmit light of a different wavelength.

[0035] According to one or more embodiments described and discussed herein, the image forming device 120 includes one or more digital micromirror devices (DMDs). The one or more DMDs are configured to form a virtual mask. In some embodiments, multiple color images are combined to form one or more composite images.

[0036] In some embodiments, one or more additional projection lenses (not shown) are disposed between the image forming device 120 and the reactive layer 110. The one or more additional projection lenses further focus the light passing through the image forming device 120 onto the reactive layer 110 disposed below the image forming device.

[0037] In one or more embodiments, the lithography apparatus 100 includes an image forming device 120 including two photomasks, a light source system 130 including two light sources, a beam splitter, and projection lenses, wherein the beam splitter focuses light emitted from the two light sources onto these projection lenses.

[0038] In one or more embodiments, the lithography apparatus 100 includes: an image forming device 120 including two photomasks; a light source system 130 including two light sources; and two projection lenses, wherein light emitted from the two light sources is respectively focused onto one of the projection lenses.

[0039] In one or more embodiments, the lithography apparatus 100 includes an image forming device 120 including two virtual masks (e.g., two DMDs); a light source system 130 including two light sources; a beam splitter; and a projection lens, wherein the beam splitter focuses light from the two light sources onto the projection lens.

[0040] In one or more embodiments, the lithography apparatus 100 includes an image forming device 120 including two virtual masks (e.g., two DMDs); a light source system 130 including two light sources; and two projection lenses, wherein light emitted from the two light sources is respectively focused onto one of these projection lenses.

[0041] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 including a virtual mask (eg, a DMD); and a light source system 130 including a single light source that sequentially emits light of multiple wavelengths.

[0042] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 including a multi-color mask, an optical device 104 , and a light source system 130 including a single light source that sequentially emits light of multiple wavelengths.

[0043] Controller 190 is configured to control and automate lithographic apparatus 100. As shown, controller 190 includes a central processing unit (CPU) (not shown), memory (not shown), and auxiliary circuitry (or I / O) (not shown). A CPU is any form of computer processor used in industrial settings to control various programs and hardware (e.g., pattern generators, motors, and other hardware), as well as to monitor processes (e.g., processing time and substrate positioning or location). Memory (not shown) is connected to the CPU and is one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, or any other form of local or remote digital storage. Software instructions and data can be encoded and stored in the memory for use in directing the CPU. Auxiliary circuitry (not shown) is also connected to the CPU to assist with the processing in a conventional manner. Auxiliary circuitry includes conventional cache memory, power supplies, clock circuits, input / output circuits, subsystems, and the like. Programs (or computer instructions) readable by controller 190 determine which tasks the lithographic apparatus 100 can perform.

[0044] The reactive layer 110 is configured to react to light of different wavelengths. In some embodiments, different portions of the reactive layer 110 can be configured to react to light of different wavelengths. According to one or more embodiments described and discussed herein, the reactive layer 110 has a first region configured to react to light of a first wavelength and a second region configured to react to light of a second wavelength. According to one or more embodiments described and discussed herein, the first region and the second region at least partially overlap.

[0045] In other embodiments, reactive layer 110 comprises a uniform material. In these embodiments, different portions of reactive layer 110 are exposed to light of different wavelengths. Consequently, different portions of reactive layer 110 (e.g., the first and second regions) react differently to the wavelengths of light to which they are exposed, even though each portion is made of the same material. According to one or more embodiments described and discussed herein, the first region and the second region at least partially overlap.

[0046] Reactive layer 110 may include any material that is photosensitive at a specific wavelength. For example, reactive layer 110 may include a first metal that is more photosensitive at a first wavelength, and reactive layer 110 may include a second metal that is more photosensitive at a second wavelength. In another example, reactive layer 110 may include a first polymer that is more photosensitive at a first wavelength, and reactive layer 110 may include a second polymer that is more photosensitive at a second wavelength.

[0047] The light incident on the reaction layer 110 can have an intensity gradient, such as a Gaussian distribution. Therefore, different portions of the reaction layer 110 can receive different doses of light. The material of the reaction layer 110 can change its water solubility depending on the applied light dose. Thus, the material can have soluble, partially soluble, or insoluble regions depending on the applied light dose.

[0048] In some embodiments, the solubility of the material does not change until a treatment process, such as a post-exposure bake, is applied to the reactive layer 110. The treatment process may include heating the reactive layer 110 to a temperature of about 70°C to about 200°C for a time of about 10 seconds to about 300 seconds.

[0049] Reactive layer 110 may include one or more photoacid generators (PAGs) and / or photobase generators (PBGs). PAGs include functional groups, such as hydrogen and / or protons, that generate acids upon absorption of light of a specific wavelength. PAGs generate strong acids due to photodissociation and / or proton dissociation upon photoassociation (e.g., a closed loop). PBGs include functional groups that generate alkali ions (e.g., amine compounds) upon absorption of light of a specific wavelength. PAGs and PBGs may be photosensitized at the same or different wavelengths.

[0050] Additionally, PAGs and PBGs that become photosensitized at the same wavelength can have different acid and base formation rates and / or acid and base concentrations. Similarly, PAGs and PBGs that become photosensitized at the same wavelength can have acid and base formation rates and / or acid and base concentrations that depend on the dose of light absorbed. Thus, a material that includes both PAGs and PBGs that are sensitive at approximately the same wavelength can have acidic, basic, or neutral regions, depending on the dose and wavelength of light applied to the region.

[0051] The solubility of a material can vary depending on the acidity / alkalinity of the material. For example, a material may include a polymer containing a water-soluble retardant or protecting group. When enough PAG is activated, the soluble groups are cleaved or deprotected by the acidic molecules, and the acid unwinds the polymer chains of the material, making the material more soluble. If PBG is also activated, the alkaline molecules neutralize the acidic molecules, thereby protecting the soluble groups, preventing the polymer from unwinding, and the material remains insoluble or poorly soluble. PBG can also induce polymer crosslinking in the material, thereby reducing the effectiveness of the acid deprotection. Therefore, depending on the dose of light and the wavelength of the applied light, a material containing both PAG and PBG that are sensitive at approximately the same wavelength can have soluble, partially soluble, or insoluble regions.

[0052] Light incident on the reaction layer 110 may have an intensity gradient, such as a Gaussian distribution. Therefore, different portions of the reaction layer 110 may receive different doses of light. Consequently, different portions of the reaction layer 110, including both PAGs and PBGs sensitive at the same wavelength, may be acidic, basic, or neutral, depending on the dose of light received.

[0053] In one or more embodiments, the reactive layer 110 includes a first PAG and a first PBG. The first PAG and the first PBG are photosensitive to light of a first wavelength.

[0054] Under a high dose of light of the first wavelength, the PBG produces more basic molecules than the acidic molecules produced by the PAG, and a high-dose region is generated in the first region. The higher basicity of the high-dose region can make the high-dose region more soluble or less soluble than the unreacted first region. As a result, the high-dose region can be easier or more difficult to etch away as an unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion. According to one or more embodiments described and discussed herein, the high-dose region has at least about 10% to 20% net basic molecules compared to acidic molecules.

[0055] In one or more embodiments, the high dose regions will have a net base concentration that will not result in deprotection of the poly-t-BOC after the post-exposure bake and thus remain insoluble in aqueous base developers, such as tetramethylammonium hydroxide (TMAH).

[0056] Under a medium dose of light of the first wavelength, the PAG produces more acidic molecules than the PBG produces basic molecules, resulting in a medium-dose region within the first region. The higher acidity of the medium-dose region can make the medium-dose region more or less soluble compared to the unreacted first region. Consequently, the medium-dose region may be more difficult or easier to etch away, resulting in an unreacted portion. According to one or more embodiments described and discussed herein, the medium-dose region has a net acidic molecule content of at least approximately 10% to 20% relative to the basic molecule content.

[0057] In one or more embodiments, the mid-dose region has a net acid concentration that will cause net deprotection of poly-t-BOC after a post-exposure bake and will be soluble in an aqueous base developer (eg, TMAH).

[0058] Under a low dose of light of the first wavelength, PAG produces few acidic molecules and PBG produces few basic molecules, resulting in a low-dose region within the first region. The neutral molecules in the low-dose region have approximately the same solubility as the unreacted first region. Therefore, the low-dose region is approximately as difficult to etch as the unreacted portion.

[0059] In one or more embodiments, the low dose areas will not undergo deprotection of the poly-t-BOC after the post-exposure bake and therefore remain insoluble in aqueous alkaline developers (eg, TMAH).

[0060] In one or more embodiments applicable with the embodiments described below, above, or separately, the first PBG is also photosensitive to light of the second wavelength, while the first PAG is not photosensitive to light of the second wavelength. Under high doses of light of the second wavelength, the first PBG generates basic molecules. The higher basicity of the high-dose region can make the high-dose region more soluble or less soluble than the unreacted first region. Therefore, the high-dose region can be easier or more difficult to etch away, resulting in an unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion.

[0061] In one or more embodiments applicable with the embodiments described below, above, or separately, the reactive layer 110 further includes a second PBG that is also photosensitive to light of a second wavelength, while the first PBG is not photosensitive to light of the second wavelength. Under high doses of light of the second wavelength, the PBG generates basic molecules. The higher basicity of the high-dose region can make the high-dose region more or less soluble than the unreacted first region. Therefore, the high-dose region can be easier or harder to etch away, resulting in an unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion.

[0062] In one or more embodiments applicable with the embodiments described below, above, or separately, the reactive layer 110 includes a first PAG and a first PBG. The first PAG and the first PBG are photosensitized to light of a first wavelength. The reactive layer 110 also includes a second PBG photosensitized to light of a second wavelength. The dose of light of the second wavelength in a portion of the reactive layer 110 is sufficiently large that the second PBG generates a large number of basic molecules. When this portion receives light of the first wavelength, the first PAG generates acidic molecules, but the number of acidic atoms is less than the number of basic molecules generated by the first and second PBGs. Therefore, the solubility of this portion is not reduced. The reactive layer 110 exhibits a bitonic behavior (e.g., a dose of light received at a given portion of the reactive layer 110 results in either a soluble portion (first hue) or an insoluble portion (second hue)). In other embodiments, multiple ranges of solubility are generated, resulting in the reactive layer 110 exhibiting a multitonal behavior.

[0063] In other embodiments, the reactive layer 110 includes photocrosslinking groups in addition to or without the PBG. In other embodiments, the material includes additional PAGs and PBGs, allowing for more than two photosensitive wavelengths. In other embodiments, the first PBG is also photosensitive to light of a second wavelength.

[0064] In some embodiments, the solubility of the reactive layer 110 does not change until the reactive layer 110 undergoes a treatment process. In these embodiments, the first and second wavelengths can be applied in any order, as long as the portion containing the first and / or second PBGs receives the second wavelength prior to the treatment process. The treatment process can include a thermal bake process. The bake process provides thermal energy to the acidic molecules, allowing them to diffuse into the polymer protecting groups, while the bake provides the reaction energy to drive the deprotection reaction. In the presence of the PBG, the thermal bake provides activation energy to cause the basic molecules to diffuse, allowing them to contact and neutralize the acid.

[0065] In one or more embodiments, the material of the reaction layer 110 includes one or more novolac resins and a cross-linking compound, wherein the cross-linking compound includes naphthoquinone diazide (C 10H6N2O) [DNQ] and bis(azide). Exemplary novolac resins may be or include one or more phenolic resins (PF) having a molar ratio of formaldehyde to phenol of less than 1. When DNQ is photoactivated, the solubility of the phenolic resin increases. When the bis(azide) is photoactivated, the bis(azide) crosslinks the novolac resin, and the novolac resin becomes insoluble or poorly soluble. DNQ is photosensitized to light of a first wavelength of about 350 nm to about 425 nm, while the bis(azide) is photosensitized to light of a second wavelength of less than about 350 nm or greater than about 425 nm. The material of the reaction layer 110 becomes more soluble at the first wavelength and becomes less soluble or insoluble at the second wavelength.

[0066] In other embodiments, the material comprises a polymer resin, such as poly-t-BOC (poly(tert-butyloxycarbonyloxystyrene)), the first region comprises a PAG (e.g., iodonium triflate), and the second region comprises a PBG (e.g., nitroformyloxycarbonyl (NVOC) piperidine). When exposed to light of a first wavelength of approximately 240 nm to approximately 250 nm, the reactive layer 110 exhibits one behavior because both the PAG (iodonium triflate) and the PBG (NVOC piperidine) are reactive to the first wavelength. When exposed to light of a second wavelength of approximately 300 nm to approximately 375 nm, the reactive layer 110 exhibits a second reactive behavior because only the PBG (NVOC piperidine) is reactive within this wavelength band. Under the first wavelength, both the PAG and the PBG are photosensitized, thereby creating a dual-tuning behavior. Under the second wavelength of light, only the PBG generator is photosensitive and will neutralize any acid attempting to deprotect the poly-t-BOC photoresist.

[0067] Figure 2 is a flow chart of a method 200 including operations for patterning a layered structure according to one or more embodiments described and discussed herein. Figure 2 、 Figures 3A to 3F 、 Figures 4A to 4C 、 Figures 5A to 5C and Figure 6 The method operations are described, but one skilled in the art will understand that any system configured to perform the method operations in any order falls within the scope of the embodiments described herein. Method 200 may be stored or accessed by controller 190 as a computer-readable medium containing instructions that, when executed by a processor of controller 190, cause lithographic apparatus 100 to perform method 200.

[0068] The method 200 begins at operation 210, where a reactive layer 110 is disposed on a substrate to create a layered structure. In one or more embodiments, the reactive layer 110 is disposed on a layered structure 117. The reactive layer 110 can be disposed using any standard method. For example, the reactive layer 110 can be deposited by wet coating deposition, a spin coating process, and / or the like.

[0069] In one or more embodiments, the reactive layer 110 comprises a premixed photoresist, wherein the PAG and PBG are mixed into the photoresist. The photoresist is spin-coated onto the layered structure. The photoresist is baked at a temperature of about 50° C. to about 150° C. for a period of about 30 seconds to about 300 seconds. The baking evaporates the solvent, thereby forming a polymer thin film photoresist.

[0070] Figure 3A The figure illustrates a top view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figure 3B The figure illustrates a cross-sectional side view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figures 3A-3B The figure shows the reaction layer 110 after it is disposed on a substrate 115. As shown, the reaction layer 110 includes one or more photosensitive chemical compounds (reaction materials 300) designed to produce different reaction results under different wavelengths of light.

[0071] In one or more embodiments, the reactive material 300 includes a first PAG (e.g., iodonium triflate) and a first PBG (e.g., nitroformyloxycarbonyl (NVOC) piperidine), and the first PAG and the first PBG are photosensitive at a first wavelength of 240 nm to about 250 nm. The first PBG is also photosensitive at a second wavelength of about 300 nm to about 375 nm.

[0072] As shown, the reactive material 300 includes a first region 301, two second regions 302, and two overlapping regions 305. The first region 301 is the region of the reactive material 300 to be exposed to light of a first wavelength. The second region 302 is the region of the reactive material 300 to be exposed to light of a second wavelength. The overlapping region 305 is the region of the reactive material 300 to be exposed to light of both the first and second wavelengths. Figures 3A to 3F The figure illustrates a reactive material having one first region, two second regions, and two overlapping regions, but the present invention is not limited thereto and may include any number of first regions, second regions, and / or overlapping regions, depending on the pattern desired by the operator. Furthermore, the first, second, and overlapping regions may have any desired shape. In some embodiments, the first and second regions do not overlap, and thus, there is no overlapping region. In some embodiments, a third region is included that receives light of a third wavelength.

[0073] In operation 220, the reactive layer 110 is exposed to light of multiple wavelengths. For example, the light source system 130 exposes the reactive layer 110 to light of first and second wavelengths. The image forming device 120 directs the light such that light of the first wavelength is incident on the first region 301, light of the second wavelength is incident on the second region 302, and the light of the first wavelength and the light of the second wavelength are incident on the overlapping region 305.

[0074] Figures 4A to 4C The diagram illustrates light having a first wavelength incident on the reactive layer 110 according to one or more embodiments described and discussed herein. Figures 4A to 4C The figure shows a first region 301 of the reaction layer 110 . Figure 4A The diagram shows the first region 301 when the waveform 401 is only incident on the reactive layer 110 , but before the material of the active layer starts to react from the light. Figure 4A The waveform 401 shown in FIG. 4 has a Gaussian shape, but waveforms of other shapes are contemplated.

[0075] As shown, waveform 401 includes a high-dose region 411, two medium-dose regions 412, and two low-dose regions 413. High-dose region 411 has a higher intensity than medium-dose region 412. Medium-dose region 412 has a higher intensity than low-dose region 413. Waveform 401 is divided into high-dose region 411, medium-dose region 412, and low-dose region 413, depending on the desired effect of light incident on the underlying reaction layer 110. High-dose region 411, medium-dose region 412, and low-dose region 413 are incident on high-dose region 311, medium-dose region 312, and low-dose region 313 of first region 301, respectively.

[0076] In some embodiments, the average intensity of the medium-dose region 412 is about 60% to about 70% of the average intensity of the high-dose region 411. In some embodiments, the average intensity of the low-dose region 413 is about 30% to about 40% of the average intensity of the high-dose region 411. The combined width of the medium-dose region 412 is about the same as the width of the high-dose region 411. The combined width of the low-dose region 413 is about the same as the width of the high-dose region 411. The width of the high-dose region 411 is about 50 nm to about 1 μm.

[0077] Figure 4B The figure shows the first region 301 when the waveform 401 is incident on the reactive layer 110 and the material of the reactive layer 110 is affected by the waveform 401. Figure 4BIn the illustrated embodiment, high-dose region 311 and low-dose region 313 do not significantly react to the first wavelength of light. However, medium-dose region 312 reacts to the first wavelength of light, converting the material in medium-dose region 312 into reacted material 320.

[0078] In one or more embodiments, in high-dose region 311, the first PBG generates more basic molecules than the acidic molecules generated by the first PAG. The higher basicity of high-dose region 311 allows the high-dose region to have the same solubility as the unreacted portion. The base covers the acid, so there is no net acid available to deprotect the photoresist during the post-exposure bake.

[0079] In mid-dose region 312, the first PAG generates more acidic molecules than the basic molecules generated by the first PBG. The higher acidity of mid-dose region 312 makes it more soluble than the unreacted first region. When the post-exposure bake drives acid diffusion and reaction kinetics to deprotect the photoresist (e.g., cleave protecting groups from the polymer), the higher acidity of the mid-dose region makes the polymer more soluble (e.g., in TMAH aqueous developer).

[0080] In low-dose region 313, the first PAG produces few acidic molecules, and the first PBG produces few basic molecules. The neutrality in low-dose region 313 has approximately the same solubility as the unreacted first region. Therefore, medium-dose region 312 is more easily etched than the unreacted portion. High-dose region 311 and low-dose region 313 have slower dissolution rates, thus leaving the reacted layer 110 after pattern development.

[0081] Figure 3C The figure illustrates a top view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figure 3D The figure illustrates a cross-sectional side view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figure 3C and 3D The diagram shows the reactive layer 110 after it has been exposed to light of a first wavelength and light of a second wavelength. Edge region 360 is located at overlap region 305. Although overlap region 305 was exposed to both the first and second wavelengths of light, the material in the overlap region remained unreacted. However, mid-dose region 312 was converted to reacted material 320.

[0082] In one or more embodiments, the first region 301 and the second region 302 at least partially overlap in an overlap region 305. The dose of the second wavelength light in the overlap region 305 is sufficiently high to cause the first PBG to generate a large number of basic molecules. When the overlap region receives the first wavelength light, the first PBG generates acidic molecules, but the number of acidic atoms is less than the number of basic molecules generated by the first and / or second PBGs. Therefore, the solubility in the overlap region 305 is not reduced.

[0083] At operation 230, the reaction layer is exposed to a treatment process. The treatment process may include any treatment process known in the art. In one or more embodiments, the reaction layer 110 is exposed to a treatment process. According to one or more embodiments described and discussed herein, the treatment process includes heating the reaction layer 110 to a temperature of about 70°C to about 200°C for a time of about 10 seconds to about 300 seconds. According to one or more embodiments described and discussed herein, the treatment process includes exposing the reaction layer 110 to a positive developer solution, such as a developer solution containing about 2% to about 5% TMAH. According to one or more embodiments described and discussed herein, the treatment process includes exposing the reaction layer 110 to a negative developer solution, such as a developer solution containing toluene.

[0084] Figure 3E The figure illustrates a top view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figure 3F The figure illustrates a cross-sectional side view of a portion of a reaction layer 110 according to one or more embodiments described and discussed herein. Figure 3E and Figure 3F The diagram shows the reaction layer 110 after it has undergone a treatment process. Figure 4C The figure shows the first region 301 after treatment. The medium dose region 312 has been removed to form one or more trenches 350. The trenches 350 may have a thickness of about 1 nm to about 100 nm and a width of about 50 nm to about 1 μm.

[0085] After the method 200 is completed, a metal layer may be deposited in the trench 350 and the reactive material 300 removed. Thus, the method 200 may be used to form a circuit comprising a metal layer of a desired shape determined by the method 200.

[0086] Although method 200 is described using a positive photoresist process (e.g., method 200 causes the reacted material 320 to become more soluble), the same method 200 can be applied to a negative photoresist process. In these embodiments, the mid-dose region 312 becomes less soluble after exposure to light of the first wavelength, and the treatment process removes the remaining portion of the reacted layer 110. For example, the reacted layer 110 is exposed to toluene for a period of about 30 seconds to about 300 seconds to remove the reacted layer 110 and retain the reacted material 320. Method 200 can also be performed using a dual tone lithography method, including both positive and negative photoresist methods.

[0087] While the above-described method 200 includes receiving light of two different wavelengths in different regions of the reactive layer 110, other methods are contemplated. In one or more embodiments, the reactive layer 110 includes two or more different regions, each region including a different photosensitive material. The different photosensitive materials are photosensitive to light of different wavelengths. The entire reactive layer can be exposed to light of different wavelengths, so that the materials of the reactive layer react to form a desired pattern.

[0088] According to one or more embodiments described and discussed in this case, Figures 5A-5B The figure shows a cross-sectional side view of a portion of a workpiece 500 including a reaction layer 110 at different stages of processing, and Figure 5C The figure shows Figure 5B A top view of a portion of the workpiece 500 described in FIG. Figure 5A As shown, the workpiece 500 includes a reactive layer 110 comprising a reactive material disposed on a substrate 115. As described and discussed herein, a method of patterning a layered structure on the workpiece 500 may be performed on the lithographic apparatus 100.

[0089] In one or more embodiments, the reactive material comprises one or more polymeric photoresist materials, one or more PAGs, and one or more PBGs. The PAGs are sensitive to or activated by light having a first wavelength, while the PBGs are sensitive to or activated by light having a second wavelength different from the first wavelength. The first wavelength is about 240 nm to about 250 nm, and the second wavelength is about 350 nm to about 410 nm.

[0090] In one or more instances, the polymer photoresist material is or includes one or more polymer resins (e.g., poly-t-BOC). In one or more instances, the PAG is or includes one or more trifluoromethanesulfonate compounds (e.g., iodonium trifluoromethanesulfonate). In one or more instances, the PBG is or includes a cyanoacrylate chromophore and a bicyclic nitrogenous base. An example of a cyanoacrylate chromophore includes a (E)-3-(2,2'-bithiophene-5-yl)-2-cyanoacrylate chromophore. Examples of bicyclic nitrogenous bases can include 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD).

[0091] like Figure 5B As shown by the arrows in FIG, the workpiece 500 is exposed to a first light 512 having a first wavelength and a second light 514 having a second wavelength. When exposed to the first light 512 of the first wavelength, a first pattern region 502 ( Figure 5A ). The first pattern area 502 may be or may include grooves, vias, contact vias, channels, and / or other openings that may have any shape, size, geometry, or pattern. Similarly, when exposed to the second light 514 of the second wavelength, the second pattern area 504 ( Figure 5A ). The second pattern area 504 can be a negative of the first pattern area 502. In some examples, the first pattern area 502 remains unexposed to the second light 514 having the second wavelength, while the second pattern area 504 remains unexposed to the first light 512 having the first wavelength. The exposure of the first pattern area 502 and the second pattern area 504 to the first light 512 and the second light 514, respectively, occurs simultaneously. For example, an acid is generated in one of the first pattern area 502 or the second pattern area 504 of the reactive material, while a base is generated in another pattern area different from the pattern area containing the generated acid. In this way, an acid is generated in the first pattern area 502 and a base is generated in the second pattern area 504. Alternatively, a base is generated in the first pattern area 502 and an acid is generated in the second pattern area 504.

[0092] In one or more embodiments, Figure 5B As shown, the acid generated by the PAG is marked as 522 in the first pattern area 502, and the base generated by the PBG is marked as 524 in the second pattern area 504. In other embodiments not shown, the acid generated from the PAG can be located in the second pattern area 504, and the base generated from the PBG can be located in the first pattern area 502.

[0093] In any example, neutralization zone 508 is produced by the reaction of acid and alkali at the interface between first pattern area 502 and second pattern area 504. Neutralization zone 508 comprises one or more salts produced by acid and alkali at the interface of pattern area 502,504. Neutralization zone 508 (such as between pattern area 502,504) provides the feature of sharp and clear edge, compared to traditional photolithography, and this and then provide enhanced resolution in the photolithography of this case description and discussion. Neutralization zone 508 provides the region between the blocking of the forward reaction that occurs in a region (such as pattern area 502 or 504) and the forward reaction that occurs in adjacent region. For example, there is the acid in the reaction material of pattern area 502 or 504, removed the protecting group on the polymer photoresist material, and the alkali of the reaction material in another pattern area 502 or 504 prevents the deprotection of the protecting group on the polymer photoresist material.

[0094] As described and discussed above at operation 230, the workpiece 500 including the first patterned area 502 and the second patterned area 504 can be exposed to a treatment process. During the treatment process, the first patterned area 502 and the second patterned area 504 are exposed to one or more developer solutions. In one or more embodiments, the first patterned area 502 of reactive material is removed during the treatment process, while the second patterned area 504 of reactive material remains. The developer solution can be a positive developer solution including one or more developer bases. Alternatively, the developer solution can be a negative developer solution including one or more developer acids.

[0095] In some embodiments, a method of patterning a layered structure includes the steps of: simultaneously exposing a first patterned region 502 of a reactive material to a first light 512 of a first wavelength and a second patterned region 504 of the reactive material to a second light 514 of a second wavelength; generating an acid in the first patterned region 502 of the reactive material and a base in the second patterned region 504 of the reactive material; and generating a neutralized region 508 at an interface between the first patterned region 502 and the second patterned region 504 from the generated acid and the generated base. The method further includes the step of exposing the first patterned region 502 and the second patterned region 504 of the reactive material to a developer solution (e.g., a positive developer solution) during a treatment process, such that the first patterned region 502 of the reactive material is removed during the treatment process while the second patterned region 504 of the reactive material is retained. In other examples, the developer solution is a negative developer solution, such that the first patterned region 502 of the reactive material is retained during the treatment process while the second patterned region 504 of the reactive material is removed.

[0096] In one or more embodiments, the reactive material in the reactive layer comprises one or more polymeric photoresist materials, one, two, or more crosslinking inhibitors, and optionally one or more quenchers. In some examples, the reactive material comprises one or more polymeric photoresist materials, a first crosslinking inhibitor, and a second crosslinking inhibitor. In other examples, the reactive material comprises one or more polymeric photoresist materials, a crosslinking inhibitor, and one or more quenchers.

[0097] In one or more embodiments, a method for patterning a layered structure includes the steps of: disposing a reactive material on the layered structure and / or substrate. The reactive material includes a polymer photoresist material, a first cross-linking inhibitor, and a second cross-linking inhibitor. The first cross-linking inhibitor is sensitive at a first wavelength, and the second cross-linking inhibitor is sensitive at a second wavelength different from the first wavelength. The method also includes the following steps: simultaneously exposing a first pattern area of ​​the reactive material to a first light of a first wavelength and exposing a second pattern area of ​​the reactive material to a second light of a second wavelength, thereby generating a first activated cross-linking inhibitor in the first pattern area of ​​the reactive material and simultaneously generating a second activated cross-linking inhibitor in the second pattern area of ​​the reactive material; and, generating a neutralization zone from the first activated cross-linking inhibitor and the second activated cross-linking inhibitor at the interface between the first pattern area and the second pattern area.

[0098] Figure 6 The figure shows a top view of a portion of a workpiece 600 including a reactive layer 110 at a processing stage according to one or more embodiments described and discussed herein. The workpiece 600 is similar to the workpiece 500, but the workpiece 600 also has a third patterned area 506 of reactive material that is exposed to both the first light and the second light, as shown in FIG. Figure 6 The third pattern region 506 may be a cut area or region on the workpiece 600. Thus, during the treatment process of operation 230, after the reactive material in the first pattern region 502 is removed, the reactive material in the third pattern region 506 may remain on the workpiece 600 along with the reactive material in the second pattern region 504.

[0099] In one or more embodiments, the workpiece 600 includes a reactive layer 110 comprising a reactive material disposed on a layered structure or substrate. The reactive material comprises one or more polymer photoresist materials, one or more PAGs, and one or more PBGs. The PAGs are sensitive at a first wavelength, and the PBGs are sensitive at a second wavelength different from the first wavelength. The method includes the steps of simultaneously exposing a first patterned area 502 of the reactive material to a first light of a first wavelength, exposing a second patterned area 504 of the reactive material to a second light of a second wavelength, and exposing a third patterned area 506 of the reactive material to the first light of the first wavelength and the second light of the second wavelength. In some instances, the third patterned area 506 is a portion of the first patterned area 502, such as Figure 6 In other examples, the third pattern area 506 is a portion of the second pattern area 504 (not shown). In other examples, the third pattern area 506 is a portion of both the first pattern area 502 and the second pattern area 504 (not shown).

[0100] The method further includes the steps of generating an acid from the PAG in the first patterned area 502 of the reactive material, and generating a base from the PBG in the second patterned area 504 and the third patterned area 506 of the reactive material. A neutralization zone 508 is disposed at the interface between the first patterned area 502 and the second patterned area 504, and between the first patterned area 502 and the third patterned area 506. In one or more examples, the first patterned area 502 remains unexposed to the second light having the second wavelength, the second patterned area 504 remains unexposed to the first light having the first wavelength, and the third patterned area 506 is exposed to both the first light having the first wavelength and the second light having the second wavelength.

[0101] As described above, a photolithography apparatus, patterning system, and method for patterning a layered structure are provided. The patterning system includes an image forming device and a reactive layer. The patterning system allows for the creation of a photolithographic pattern. The photolithography apparatus includes a patterning system and an optical system. The photolithography apparatus and the image forming device use light of multiple wavelengths to form multiple different color images and / or patterns on the reactive layer. The patterning method includes exposing the reactive layer to light of multiple different wavelengths. The reactive layer reacts differently to light of different wavelengths, thereby enabling the formation of multiple color images and / or one or more composite images in a single photolithography step.

[0102] The disclosed method and apparatus require a single lithography step that produces a net composite image that would otherwise require multiple lithography steps and multiple masks. Furthermore, the use of an image forming device reduces the need for multiple mask alignment, thereby reducing lithography time.

[0103] Although the foregoing is directed to the embodiments of the present invention, other and further embodiments may be designed without departing from the basic scope of the present invention, and the scope of the present invention is determined by the scope of the claims. All documents described in the present invention are incorporated herein by reference, including any priority documents and / or test procedures that are not inconsistent with the present invention. It is apparent from the general description and specific embodiments above that, although the forms of the present invention have been shown and described, various modifications may be made without departing from the spirit and scope of the present invention. Therefore, there is no intention to limit the present invention in this manner. Similarly, for legal purposes, the term "comprising" shall be considered synonymous with the term "including". Similarly, whenever the transitional term "comprising" is added before a composition, an element, or a group of elements, it shall be understood as having the transitional term "essentially consisting of," "consisting of," "selected from a combination consisting of," or "is" before the description of the composition, element, or multiple elements, and vice versa.

[0104] As used herein, the term "about" refers to a variance of + / - 10% from the nominal value. It should be understood that such variance is included in any value provided herein.

[0105] Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It should be understood that, unless otherwise indicated, ranges including combinations of any two values ​​are contemplated, e.g., any lower value combined with any higher value, any two lower values ​​combined, and / or any two higher values ​​combined. Certain lower limits, upper limits, and ranges are shown in one or more claims below.

Claims

1. A lithographic apparatus comprising: a substrate support configured to support the layered structure; a light source system configured to emit light having two or more wavelengths, the wavelengths including a first wavelength and a second wavelength; as well as An image forming device is configured to project two or more different color images into the photoresist corresponding to two or more different sets of device geometries.

2. The lithographic apparatus of claim 1 , wherein The light source system includes a light source configured to emit light having the two or more wavelengths, The image forming device includes a mask, and The mask is configured to project a light pattern having the two or more wavelengths.

3. The lithographic apparatus of claim 2, wherein: The mask includes at least one spatial light modulator, wherein the mask is configured to sequentially project the light images having the two or more wavelengths.

4. The lithographic apparatus of claim 3, wherein: The at least one spatial light modulator is a digital micromirror device (DMD).

5. The lithographic apparatus according to claim 2, wherein: The mask comprises: a first spatial light modulator configured to project light having the first of the two or more wavelengths, and A second spatial light modulator is configured to project light having the second wavelength of the two or more wavelengths.

6. The lithographic apparatus of claim 5, wherein: The first spatial light modulator is a first digital micromirror device (DMD), and the second spatial light modulator is a second DMD.

7. The lithographic apparatus of claim 2, wherein: The mask includes a first photomask and a second photomask, The first photomask is configured to project light having the first wavelength of the two or more wavelengths, and The second photomask is configured to project light having the second wavelength of the two or more wavelengths.

8. A lithographic apparatus comprising: a substrate support configured to support the layered structure; a light source system capable of emitting light having two or more wavelengths, the wavelengths including a first wavelength and a second wavelength; as well as An image forming apparatus comprising a mask operable to: generating a first light pattern having the first wavelength to be projected onto a first region of the layered structure; as well as A second light pattern having the second wavelength is generated to be projected onto a second region of the layered structure, the first light pattern and the second light pattern having different doses.

9. The lithographic apparatus of claim 8, wherein a portion of the second light image projected onto the second region at least partially overlaps with the first light image projected onto the first region.

10. The lithographic apparatus of claim 8, wherein the mask comprises at least one spatial modulator configured to project a light pattern having the two or more wavelengths.

11. The lithographic apparatus of claim 10, wherein The first spatial modulator includes a first digital micromirror device (DMD), and the second spatial modulator includes a second DMD, The first DMD is configured to project light having the first wavelength of the two or more wavelengths, and The second DMD is configured to project light having the second wavelength of the two or more wavelengths.

12. A method for patterning a layered structure, comprising the steps of: providing a reaction layer on the layered structure; and The reaction layer is exposed to light of multiple wavelengths by an image forming device, wherein the reaction layer includes a reaction material, and the reaction material includes a first region and a second region. The step of exposing the reaction layer includes the following steps: generating a first light pattern having a first wavelength to the first region of the reactive layer; and A second light pattern having a second wavelength is generated to the second region of the reactive layer, the first light pattern and the second light pattern having different doses.

13. The method of claim 12, wherein the reaction layer is exposed by the image forming device comprising the following device regions: a first device region capable of generating the first light pattern having the first wavelength to be projected onto the first region of the reactive layer; and The second device region is capable of generating the second light pattern having the second wavelength, so as to be projected onto the second region of the reactive layer.

14. The method of claim 12, wherein the image forming device comprises a photomask, and the first light image and the second light image are projected through the photomask. 15 . The method of claim 12 , wherein the image forming device comprises a first photomask and a second photomask, and the first light image is projected through the first photomask and the second light image is projected through the second photomask.

16. The method of claim 12, wherein the reactive layer comprises photoresist and the image forming device comprises a spatial modulator comprising one or more digital micromirror devices (DMDs).

17. The method of claim 12, wherein the reactive material comprises a first photoacid generator (PAG), a first photobase generator (PBG), and a second PBG, wherein each of the first PAG and the first PBG is sensitive at the first wavelength, and the second PBG is sensitive at the second wavelength.

18. The method of claim 12, wherein the step of exposing the first region and the step of exposing the second region occur simultaneously.

19. The method of claim 12, wherein the step of exposing the first region and the step of exposing the second region occur sequentially, and the step of exposing the first region and the step of exposing the second region are repeated one or more times.

20. The method of claim 12, wherein the first region at least partially overlaps the second region.

Images