Lithographic apparatus, patterning system, and method for patterning a laminated structure

Abstract

To provide a lithography apparatus that can perform enhanced resolution lithography processes in a single lithography operation, a patterning system, and a method of patterning a layered structure.SOLUTION: A patterning system 150 includes an image formation device 120 and a reactive layer 110, and allows for creating lithography patterns in a single operation. A lithography apparatus 100 includes the patterning system and an optical system 103, and uses a plurality of wavelengths of light, along with the image formation device, to create a plurality of color patterns on the reactive layer. A method of patterning includes exposing the reactive layer to a plurality of wavelengths of light. The light reacts differently with different regions of the reactive layer, depending on the wavelength of light emitted onto the different regions. The method and apparatuses disclosed herein require only one image formation device and one lithography operation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001]

[0001] Embodiments of the present disclosure relate to apparatus and methods, and more particularly to lithographic apparatus, patterning systems, and methods for patterning layered structures. [Background technology]

[0002]

[0002] Photolithography technology plays a key role in the manufacture of integrated circuit (IC) chips. Continuing improvements in optical projection lithography have made it possible to print ever-smaller integrated circuit features, enabling the integrated circuit industry to produce more powerful and cost-effective semiconductor devices.

[0003]

[0003] In the field of optical lithography processing, a photosensitive material is applied to a substrate and then dried. An exposure tool is utilized to expose the photosensitive material-coated substrate with an appropriate geometric pattern through a mask using a light or radiation source. After exposure, the wafer is processed to develop the mask image transferred to the photosensitive material. These masking patterns are then used to form device features of a circuit.

[0004]

[0004] When the pattern resolution requirements for a single design layer exceed the capabilities of an exposure tool, the limitation can sometimes be circumvented by dividing the pattern into multiple lithographic iterations. One drawback of this approach is that many photolithographic patterns require the use of multiple masks in multiple steps, removing the substrate after the first patterning and adding a second mask, slowing the lithographic process and increasing costs for the user. Furthermore, placing the second mask requires careful alignment. Alignment errors can result in misaligned patterns, wasting resources and requiring additional time for correction.

[0005]

[0005] Therefore, improved lithographic methods are needed, and it would be beneficial to reduce the number of patterning steps required. Summary of the Invention

[0006]

[0006] Embodiments herein include a lithography apparatus, a patterning system, and a method for patterning a layered structure. The apparatus and methods provided herein are capable of performing a resolution-enhanced lithography process in a single lithography step, without requiring multiple photoresist application, development, and etching steps, or requiring multiple masks.

[0007]

[0007] In one embodiment, a lithographic apparatus is provided, which includes a substrate support configured to support a laminated structure, a light source system capable of emitting light at two or more wavelengths, and an image forming device capable of receiving light at 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.

[0008] In another embodiment, a patterning system is provided that includes an imaging device and a photosensitive reactive layer. The reactive material includes first regions and second regions. The imaging device is configured to allow light of a first wavelength to the first regions and the imaging device is configured to allow light of a second wavelength to the second regions.

[0009] In yet another embodiment, a method of patterning a laminate structure is provided, the method including disposing a reactive layer over the laminate structure and exposing the reactive layer to multiple wavelengths of light through an imaging device. The reactive layer includes a reactive material. The reactive material includes first regions and second regions. Exposing the reactive layer includes exposing the first regions to light at the first wavelength and exposing the second regions to light at the second wavelength.

[0010]

[0010] So that the above-mentioned features of the present disclosure can be understood in detail, a more particular description of the present disclosure briefly summarized above can be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings depict only exemplary embodiments and therefore should not be considered to limit the scope of the present disclosure, which may also admit of other equally effective embodiments. [Brief explanation of the drawings]

[0011] [Figure 1] 1 depicts a lithographic apparatus according to one or more embodiments described and illustrated herein; [Figure 2] FIG. 1 is a flow diagram of method steps for patterning a layered structure according to one or more embodiments described and illustrated herein. [Figure 3A] 1 shows a top view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 3B] 1 shows a cross-sectional side view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 3C] 1 shows a top view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 3D] 1 shows a cross-sectional side view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 3E] 1 shows a top view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 3F] 1 shows a cross-sectional side view of a portion of a reactive layer according to one or more embodiments described and illustrated herein. [Figure 4A] 1 shows light at a first wavelength incident on a reactive layer according to one or more embodiments described and illustrated herein. [Figure 4B] 1 shows light at a first wavelength incident on a reactive layer according to one or more embodiments described and illustrated herein. [Figure 4C] 1 shows light at a first wavelength incident on a reactive layer according to one or more embodiments described and illustrated herein. [Figure 5A-B] 1A-1D illustrate cross-sectional side views of a portion of a workpiece including a reactive layer at different stages during processing according to one or more embodiments described and illustrated herein. [Figure 5C] 5C illustrates a top view of a portion of the workpiece shown in FIG. 5B according to one or more embodiments described and illustrated herein. [Figure 6] 1 illustrates a top view of a portion of a workpiece including a reactive layer at one stage of processing according to one or more embodiments described and illustrated herein. DETAILED DESCRIPTION OF THE INVENTION

[0012]

[0023] For ease of understanding, where possible, identical reference numerals have been used to designate identical elements common to the figures. It is intended that elements and features of one embodiment may be beneficially incorporated in other embodiments without further description.

[0013]

[0024] Embodiments of the present disclosure include a lithography apparatus, a patterning system, and a method for patterning a layered structure. The patterning system includes a multi-wavelength light source, an imaging device, and a reactive layer having multiple behaviors corresponding to the multiple wavelengths of light. The patterning system enables the generation of two or more distinct lithography patterns at two or more distinct wavelengths. The lithography apparatus includes a patterning system and an optical system. The lithography apparatus uses multiple wavelengths of light, which can be individually directed by the imaging device to form multiple patterns and / or images in the reactive layer. The patterning method includes exposing the reactive layer to multiple wavelengths of light. Different wavelengths of light are exposed to different regions of the reactive layer. The different regions of the reactive layer react differently depending on the wavelength of the exposed light. The methods and apparatus disclosed herein require only a single lithography process. Furthermore, the use of a single irradiation operation reduces the need for multiple mask alignment steps, shortening lithography time. Although not limited to this, embodiments herein may be useful in a lithographic apparatus configured to provide multiple wavelengths of light to two different portions of a reactive layer.

[0014]

[0025] 1 shows a lithographic apparatus 100 according to one or more embodiments described and illustrated herein. The lithographic apparatus 100 is configured to emit images of multiple different wavelengths onto an underlying stack structure 117. The lithographic apparatus 100 may be any lithographic tool used in the art, such as, but not limited to, a mask-based lithography tool or a maskless (direct-write) lithography tool, in either a raster beam configuration or a multi-beam array configuration.

[0015]

[0026] 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 stack 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 anywhere in three-dimensional space. For example, the substrate support 116 may be lowered to receive the stack structure 117 from a robot (not shown) external to the lithographic apparatus 100.

[0016]

[0027] The laminated structure 117 is used as a workpiece for various semiconductor devices, printed circuit boards, flat panel displays, and / or other MEMS, optical devices, etc. As shown, the laminated structure 117 includes a substrate 115. The substrate 115 can be any substrate used in the art. For example, the substrate 115 includes a semiconductor material (e.g., silicon (Si), germanium (Ge), silicon germanium (SiGe), and / or a III-V semiconductor such as gallium arsenide (GaAs)). In another example, the substrate 115 includes a transparent material (e.g., glass and / or plastic). The substrate 115 may have any number of insulating, semiconductor, or metal layers thereon.

[0017]

[0028] The optical system 103 is configured to project and control images of multiple discrete wavelengths of light onto the underlying laminate 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 at multiple wavelengths (e.g., two wavelengths). The wavelengths emitted by the light source system can be anywhere in the electromagnetic range (e.g., ultraviolet (UV) light, visible light, or infrared (IR) light). According to one or more embodiments described and illustrated herein, the light source system emits light at a first wavelength of about 240 nm to about 250 nm (e.g., deep ultraviolet (DUV) light) and a second wavelength of about 300 nm to about 375 nm (e.g., UV or i-line light). The wavelengths of light are selected by one skilled in the art depending on the photosensitive reactants within the reactive layer, as described in more detail below.

[0018]

[0029] The light source system 130 may include a single light source or multiple light sources (e.g., a first light source and a second light source). The first light source and the second light source are configured to emit light at a first wavelength and a second wavelength, according to one or more embodiments described and illustrated herein. The light source system 130 may include a single light source that sequentially emits wavelengths of light, according to one or more embodiments described and illustrated herein. The light source may be any light source used in the art (e.g., 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 an argon fluoride (ArF) laser), a frequency doubled laser (such as a 1.06 μm frequency neodymium-doped yttrium aluminum garnet (Nd:YAlO) laser), or a laser with a wavelength of 1.06 μm. 12 ) [Nd:YAG] laser, frequency tripled to 353 nm or frequency tripled to 4x266 nm, a conventional mercury halogen lamp with an alternate bandpass filter alternating between about 365 nm and about 405 nm, or other light source combinations that match the behavior of multiple photosensitive reactants in the reactive layer.

[0019]

[0030] The one or more projection lenses 105 may be any projection lens used in the art (e.g., spherical lens, cylindrical lens) and may include any suitable layers or coatings thereon. The optical system 103 may further include a beam splitter (not shown) to focus the light source system 130 onto the patterning system 150 below. The beam splitter, according to one or more embodiments described and illustrated herein, focuses light emitted from the multiple light sources onto a single projection lens, which focuses the light onto the patterning system 150. The light emitted from the multiple light sources is focused by the one or more projection lenses 105, according to one or more embodiments described and illustrated herein, which focuses the light onto the patterning system 150.

[0020]

[0031] Patterning system 150 is configured to pattern a desired pattern onto laminate structure 117. As shown, patterning system 150 includes an image-forming device 120 and a reactive layer 110. Image-forming device 120 may be any used in the art for photolithography. Image-forming device 120 is configured to allow light to pass through predetermined areas. Image-forming device 120 may include any mask used in the art for lithography, such as a photomask, a virtual mask, and / or a digital mask (e.g., a spatial light modulator such as a Digital Micro Mirror Device (DMD)). Image-forming device 120 may include any number or combination of masks, for example, one mask with two different color-blocking patterns or two photomasks.

[0021]

[0032] The image-forming device 120 is operable to receive light of two or more wavelengths generated by the light source system 130 and generate two or more light images at the received wavelengths. The image-forming device 120 can include any number of regions, each configured to allow light to reach a specific portion of the reactive layer 110. In some embodiments, the image-forming device 120 includes multiple photomasks, each configured to receive light of a different wavelength. In some embodiments, the image-forming device 120 includes a multi-color mask, which absorbs specific wavelengths in specific portions of the mask while allowing other wavelengths to be transmitted through the same portions of the mask. In some embodiments, the image-forming device 120 includes multiple photomask layers, each configured to transmit light of a different wavelength.

[0022]

[0033] Image forming device 120, according to one or more embodiments described and illustrated herein, 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 create one or more composite images.

[0023]

[0034] In some embodiments, one or more additional projection lenses (not shown) are positioned 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, which is positioned below the image-forming device.

[0024]

[0035] In one or more embodiments, the lithographic apparatus 100 includes an image-forming device 120 that includes two photomasks, and a light source system 130 that includes two light sources, a beam splitter, and a projection lens, where the beam splitter focuses light emitted from the two light sources onto the projection lens.

[0025]

[0036] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 including two photomasks, and a light source system 130 including two light sources and two projection lenses, where light emitted from the two light sources is each focused onto one of the projection lenses.

[0026]

[0037] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 including two virtual masks (e.g., two DMDs), and a light source system 130 including two light sources, a beam splitter, and a projection lens, where the beam splitter focuses light emitted from the two light sources onto the projection lens.

[0027]

[0038] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 including two virtual masks (e.g., two DMDs), and a light source system 130 including two light sources and two projection lenses, where light emitted from the two light sources is each focused onto one of the projection lenses.

[0028]

[0039] In one or more embodiments, the lithographic apparatus 100 includes an image forming device 120 that includes a virtual mask (e.g., a DMD), and a light source system 130 that includes a single light source that sequentially emits light of different wavelengths.

[0029]

[0040] 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, which includes a single light source that sequentially emits light of different wavelengths.

[0030]

[0041] The controller 190 is configured to control and automate the lithographic apparatus 100. The illustrated controller 190 includes a central processing unit (CPU) (not shown), memory (not shown), and support circuits (or I / O) (not shown). The CPU may be one of any form of computer processor used in industrial environments to control various processes and hardware (e.g., pattern generators, motors, and other hardware) and monitor processes (e.g., processing time and substrate position or location). The memory (not shown) is connected to the CPU and may be one or more of readily available memory, 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 may be coded and stored in the memory for instructing the CPU. Support circuits (not shown) are further connected to the CPU for assisting the processor in a conventional manner. The support circuits may include conventional cache, power supplies, clock circuits, input / output circuits, subsystems, etc. A program (or computer instructions) readable by controller 190 determines which tasks are performable by lithographic apparatus 100 .

[0031]

[0042] The reactive layer 110 is configured to respond to different wavelengths of light. In some embodiments, different portions of the reactive layer 110 may be configured to respond to different wavelengths of light. The reactive layer 110 has a first region configured to respond to a first wavelength of light and a second region configured to respond to a second wavelength of light, according to one or more embodiments described and illustrated herein. The first region and the second region at least partially overlap, according to one or more embodiments described and illustrated herein.

[0032]

[0043] In other embodiments, the reactive layer 110 comprises a homogeneous material. In these embodiments, various portions of the reactive layer 110 are exposed to different wavelengths of light. Thus, various portions of the reactive layer 110 (e.g., first and second regions) react differently depending on the wavelength of light to which they are exposed, even though the material in each portion is the same. The first and second regions at least partially overlap, according to one or more embodiments described and illustrated herein.

[0033]

[0044] The reactive layer 110 can include any material that is photoactive in a particular light spectrum. For example, the reactive layer 110 includes a first metal that is more photoactive at a first wavelength, and the reactive layer 110 includes a second metal that is more photoactive at a second wavelength. In another example, the reactive layer 110 includes a first polymer that is more photoactive at a first wavelength, and the reactive layer 110 includes a second polymer that is more photoactive at a second wavelength.

[0034]

[0045] Light incident on the reactive layer 110 may have an intensity gradient, e.g., a Gaussian pattern. Thus, different portions of the reactive layer 110 may receive different doses of light. The material of the reactive layer 110 may change in water solubility depending on the dose of light applied. Thus, the material may have regions that are either soluble, partially soluble, or insoluble depending on the dose of light applied.

[0035]

[0046] In some embodiments, the solubility of the material does not change until a treatment process, such as a post-exposure bake, is performed on 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 about 10 seconds to about 300 seconds.

[0036]

[0047] The reactive layer 110 may include one or more photoacid generators (PAGs) and / or photobase generators (PBGs). PAGs include functional groups that generate acids, such as hydrogen and / or protons, upon absorption of light of a specific wavelength. PAGs generate strong acids due to photodissociation and / or dissociation of protons (e.g., ring closure) upon photoassociation. PBGs include functional groups that generate base ions (e.g., amine compounds) upon absorption of light of a specific wavelength. The PAGs and PBGs may be photoactive at the same wavelength or different wavelengths.

[0037]

[0048] Furthermore, PAGs and PBGs that are photoactivatable at the same wavelength may have different acid and base formation rates and / or acid-base concentrations. Furthermore, PAGs and PBGs that are photoactivatable at the same wavelength may have acid and base formation rates and / or acid-base concentrations that depend on the dose of light absorbed. Thus, a material containing both a PAG and a PBG that are active at approximately the same wavelength may have regions that are either acidic, basic, or neutral, depending on the dose and wavelength of light applied to the regions.

[0038]

[0049] The solubility of a material can vary depending on the material's acidity / basicity. For example, a material may contain a polymer containing a water-soluble blocker or protecting group. When a sufficient number of PAGs are activated, the solubilizing groups are cleaved or deprotected by acidic molecules, and the acid unwinds the polymer chains of the material, making the material more soluble. If the PBG is also activated, the basic molecules neutralize the acidic molecules, protecting the solubilizing groups, preventing the polymer from unwinding, leaving the material insoluble or less soluble. The PBG can also induce polymer crosslinking in the material, reducing the effectiveness of acid deprotection. Thus, a material containing both a PAG and a PBG active at approximately the same wavelength may have regions that are either soluble, partially soluble, or insoluble, depending on the applied light dose and wavelength.

[0039]

[0050] Light incident on reactive layer 110 may have an intensity gradient, e.g., a Gaussian pattern. Thus, different portions of reactive layer 110 may receive different doses of light. Thus, different portions of reactive layer 110 that contain both PAG and PBG active at the same wavelength may be acidic, basic, or neutral, depending on the dose of light they receive.

[0040]

[0051] In one or more embodiments, the reactive layer 110 includes a first PAG and a first PBG, the first PAG and the first PBG being active with light at a first wavelength.

[0041]

[0052] At a high dose of light of a first wavelength, the PAG generates more basic molecules than the PAG generates acidic molecules, resulting in a high-dose region in the first region. The higher basicity of the high-dose region can make the high-dose region more or less soluble than the unreacted first region. Thus, the high-dose region can be easier or more difficult to etch away, like the unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion. The high-dose region has at least about 10% to 20% more net basic molecules than acidic molecules, according to one or more embodiments described and illustrated herein.

[0042]

[0053] In one or more embodiments, the high dose regions, when post-exposure baked, will have a net base concentration that does not result in deprotection of the poly-t-BOC and thus remains insoluble in aqueous base developers such as tetramethylammonium hydroxide (TMAH).

[0043]

[0054] At a medium dose of light at a first wavelength, the PAG generates more acidic molecules than the PBG generates basic molecules, resulting in a medium dose region in the first region. The greater acidity of the medium dose region may make the medium dose region more or less soluble than the unreacted first region. Thus, the medium dose region may be more or easier to etch away, as may the unreacted portion. The medium dose region, according to one or more embodiments described and illustrated herein, has at least about 10% to 20% more net acidic molecules than basic molecules.

[0044]

[0055] In one or more embodiments, the medium dose region has a net acid concentration that, upon post-exposure baking, causes net deprotection of poly-t-BOC and is soluble in an aqueous base developer such as TMAH.

[0045]

[0056] At low doses of light at the first wavelength, PAG produces very few acidic molecules and PBG produces very few basic molecules, creating a low-dose region in the first region. The neutrals in the low-dose region have nearly the same solubility as the unreacted first region. Therefore, the low-dose region is nearly as difficult to etch away as the unreacted portion.

[0046]

[0057] In one or more embodiments, the low dose regions, upon post-exposure baking, do not result in deprotection of the poly-t-BOC and thus remain insoluble in aqueous base developers such as TMAH.

[0047]

[0058] In the embodiments described below, above, or alone, the first PBG is also photoactive at the second wavelength of light, but the first PBG is not photoactive at the second wavelength of light. At high doses of light at the second wavelength, the first PBG generates basic molecules. The higher basicity of the high-dose region may make the high-dose region more or less soluble than the unreacted first region. Thus, the high-dose region may be easier or more difficult to etch away like the unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion.

[0048]

[0059] In one or more embodiments that may be used with the embodiments described below, above, or alone, the reactive layer 110 further includes a second PBG that is photoactive at a second wavelength of light, but the first PBG is not photoactive at the second wavelength of light. At high doses of light at the second wavelength, the PBG generates basic molecules. The higher basicity of the high-dose region may make the high-dose region more or less soluble than the unreacted first region. Thus, the high-dose region may be easier or more difficult to etch away like the unreacted portion. In some embodiments, the high-dose region has the same solubility as the unreacted portion.

[0049]

[0060] In one or more embodiments that may be used with the embodiments described below, above, or independently, the reactive layer 110 includes a first PAG and a first PBG. The first PAG and the first PBG are active with light at a first wavelength. The reactive layer 110 further includes a second PBG that is photoactive with light at a second wavelength. The dose of light at the second wavelength in a portion of the reactive layer 110 is large enough to cause the second PBG to generate a large number of basic molecules. When this portion receives light at 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 PBG and the second PBG. Therefore, the solubility of this portion is not reduced. The reactive layer 110 has dual-tone behavior (e.g., the dose of light received at a given portion of the reactive layer 110 results in either a soluble portion (first tone) or an insoluble portion (second tone)). In other embodiments, multiple ranges of solubility occur, and thus the reactive layer 110 has multi-tone behavior.

[0050]

[0061] In other embodiments, the reactive layer 110 further includes a photo cross-linker in addition to or instead of the PBG. In other embodiments, additional PAGs and PBGs are included in the material, allowing for more than two photoactive wavelengths. In other embodiments, the first PBG is also photoactive at a second wavelength of light.

[0051]

[0062] 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 may be applied in either order, as long as the portion containing the first PBG and / or second PBG receives the second wavelength before the treatment process. The treatment process may include a thermal baking process. The baking process provides thermal energy for the diffusion of acidic molecules into the polymer protecting groups, and the baking provides reaction energy to drive the deprotection reaction. If a PBG is present, the thermal baking provides activation energy for the diffusion of basic molecules, allowing them to contact the acid and neutralize it.

[0052]

[0063] In one or more embodiments, the material of the reactive layer 110 may comprise one or more novolac resins, as well as diazonaphthoquinone (C 10 The novolac resin includes a crosslinking compound including (HNO)[DNQ] and a bis(azide). An exemplary novolac resin can be or include one or more phenol-formaldehyde (PF) resins having a molar ratio of formaldehyde to phenol less than 1. When the DNQ is photoactivated, the solubility of the novolac resin increases. When the bis(azide) is photoactivated, the bis(azide) crosslinks the novolac resin, making it insoluble or less soluble. The DNQ is photoactive to light at a first wavelength between about 350 nm and about 425 nm, and the bis(azide) is photoactive to light at a second wavelength either less than about 350 nm or greater than about 425 nm. The material of the reactive layer 110 becomes more soluble at the first wavelength and less soluble or insoluble at the second wavelength.

[0053]

[0064] In another embodiment, the material includes a polymer resin such as poly-t-BOC (poly(tert-butoxycarbonyloxystyrene)) having a first region containing a PAG (e.g., iodonium triflate) and a second region containing a PBG (e.g., nitroveratryloxycarbonyl (NVOC) piperidine). When exposed to light at a first wavelength of about 240 nm to about 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 of light. When the reactive layer 110 is exposed to light at a second wavelength of about 300 nm to about 375 nm, the reactive layer 110 exhibits a second reactive behavior because only the PBG NVOC piperidine is reactive in this wavelength range. At the first wavelength of light, both the PAG and the PBG are photoactive, thereby establishing a dual-tone behavior. At the second wavelength of light, only the PBG generator is photoactive, neutralizing any acid that would otherwise deprotect the poly-t-BOC photoresist.

[0054]

[0065] Figure 2 is a flow diagram of a method 200 including steps for patterning a layered structure according to one or more embodiments described and illustrated herein. Although the method steps are described with reference to Figures 2, 3A-F, 4A-C, 5A-C, and 6, one skilled in the art will recognize that any system configured to perform the method steps in any order falls within the scope of the embodiments described herein. Method 200 may be stored on or accessible to 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.

[0055]

[0066] Method 200 begins at step 210, where a reactive layer 110 is disposed on a substrate to create a laminate structure. In one or more embodiments, the reactive layer 110 is disposed on top of the laminate structure 117. The reactive layer 110 can be disposed using any standard method. For example, the reactive layer 110 can be deposited by wet coat deposition, a spin-on coating process, or the like.

[0056]

[0067] In one or more embodiments, the reactive layer 110 comprises a pre-mixed photoresist, where the PAG and PBG are mixed into the photoresist. The photoresist is spin-coated onto the laminate structure. The photoresist is baked at a temperature of about 50° C. to about 150° C. for about 30 seconds to about 300 seconds. Baking evaporates the solvent, leaving a polymeric thin-film photoresist.

[0057]

[0068] Figure 3A shows a top view of a portion of a reactive layer 110 according to one or more embodiments described and illustrated herein. Figure 3B shows a side cross-sectional view of a portion of a reactive layer 110 according to one or more embodiments described and illustrated herein. Figures 3A and 3B show the reactive layer 110 after it has been disposed on a substrate 115. As shown, the reactive layer 110 includes one or more photosensitive chemical compounds (reactive materials 300) designed to generate different reaction results with different wavelengths of light.

[0058]

[0069] In one or more embodiments, the reactive material 300 includes a first PAG, such as iodonium triflate, and a first PBG, such as nitroveratryloxycarbonyl (NVOC) piperidine, where the first PAG and the first PBG are photoactive at a first wavelength of 240 nm to about 250 nm, and the first PBG is also photoactive at a second wavelength of about 300 nm to about 375 nm.

[0059]

[0070] As shown, reactive material 300 includes a first region 301, two second regions 302, and two overlapping regions 305. First region 301 is the region of reactive material 300 exposed to light of a first wavelength. Second region 302 is the region of reactive material 300 exposed to light of a second wavelength. Overlapping region 305 is the region of reactive material 300 exposed to light of a first wavelength and a second wavelength. While FIGS. 3A through 3F show a reactive material having one first region, two second regions, and two overlapping regions, the disclosure is not so limited 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 regions, second regions, and overlapping regions may be any desired shape. In some embodiments, the first and second regions do not overlap, and therefore no overlapping regions exist. In some embodiments, a third region is included that receives light at a third wavelength.

[0060]

[0071] In step 220, the reactive layer 110 is exposed to light at multiple wavelengths. For example, light source system 130 exposes the reactive layer 110 to light at a first wavelength and a second wavelength. Imaging device 120 directs the light so that the light at the first wavelength is incident on first region 301, the light at the second wavelength is incident on second region 302, and the light at the first wavelength and the light at the second wavelength are incident on overlap region 305.

[0061]

[0072] Figures 4A through 4C show light at a first wavelength incident on the reactive layer 110 according to one or more embodiments described and illustrated herein. Figures 4A through 4C show a first region 301 of the reactive layer 110. Figure 4A shows the first region 301 when the waveform 401 has just incident on the reactive layer 110, but before the material of the active layer has begun to react to the light. The light has a waveform 401 incident on the reactive layer 110. The waveform 401 shown in Figure 4A has a Gaussian shape, although waveforms of other shapes are also contemplated.

[0062]

[0073] 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, which has a higher intensity than low-dose region 413. The division of waveform 401 into high-dose region 411, medium-dose region 412, and low-dose region 413 depends on the desired effect of the light incident on the underlying reactive 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.

[0063]

[0074] In some embodiments, the average intensity of the medium-dose regions 412 is about 60% to about 70% of the average intensity of the high-dose regions 411. In some embodiments, the average intensity of the low-dose regions 413 is about 30% to about 40% of the average intensity of the high-dose regions 411. The total width of the medium-dose regions 412 is about the same as the width of the high-dose regions 411. The total width of the low-dose regions 413 is about the same as the width of the high-dose regions 411. The width of the high-dose regions 411 is about 50 nm to about 1 μm.

[0064]

[0075] 4B shows the first region 301 as the waveform 401 is incident on the reactive layer 110 and the material of the reactive layer 110 is affected by the waveform 401. In the embodiment shown in FIG. 4B, the high-dose region 311 and the low-dose region 313 do not react significantly with the first wavelength of light. However, the medium-dose region 312 does react with the first wavelength of light. The material in the medium-dose region 312 is converted to reacted material 320.

[0065]

[0076] In one or more embodiments, in the high-dose region 311, the first PAG generates more basic molecules than the first PAG generates acidic molecules. The more basic the high-dose region 311, the more soluble it is as the unreacted portion. Because the base overwhelms the acid, there is no net acid to deprotect the resist during the post-exposure bake.

[0066]

[0077] In the mid-dose region 312, the first PAG generates more acidic molecules than the first PAG generates basic molecules. The higher acidity of the mid-dose region 312 makes it more soluble than the unreacted first region. When a post-exposure bake enhances acid diffusion and reaction rates and deprotects the resist (e.g., cleaves protecting groups from the polymer), the higher acidity of the mid-dose region makes the polymer more soluble (e.g., in a TMAH aqueous developer).

[0067]

[0078] In the low-dose region 313, the first PAG produces very few acidic molecules and the first PBG produces very few basic molecules. The neutrals in the low-dose region 313 have nearly the same solubility as the unreacted first region. Therefore, the intermediate-dose region 312 is easier to etch away than the unreacted portion. The high-dose region 311 and the low-dose region 313 dissolve more slowly, and therefore, the reactive layer 110 remains after pattern development.

[0068]

[0079] FIG. 3A shows a top view of a portion of reactive layer 110 according to one or more embodiments described and illustrated herein. FIG. 3D shows a side cross-sectional view of a portion of reactive layer 110 according to one or more embodiments described and illustrated herein. FIGS. 3C and 3D show reactive layer 110 after the reactive layer has been exposed to light at a first wavelength and light at a second wavelength. Edge region 360 is located in overlap region 305. Although overlap region 305 has been exposed to light at both the first and second wavelengths, the material in the overlap region is unreacted. However, intermediate dose region 312 has been converted to reacted material 320.

[0069]

[0080] 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 light at the second wavelength in the overlap region 305 is large enough to cause the first PBG to generate a large number of basic molecules. When this overlap region receives light at the first wavelength, the first PBG generates acidic molecules, but the number of acidic atoms is less than the number of basic molecules generated by the first PBG and / or the second PBG. Therefore, the solubility of the overlap region 305 is not reduced.

[0070]

[0081] In step 230, the reactive 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 reactive layer 110 is exposed to a treatment process. The treatment process, according to one or more embodiments described and illustrated herein, includes heating the reactive layer 110 to a temperature of about 70° C. to about 200° C. for about 10 seconds to about 300 seconds. The treatment process, according to one or more embodiments described and illustrated herein, includes exposing the reactive layer 110 to a positive developer, such as a developer containing about 2% to about 5% TMAH. The treatment process, according to one or more embodiments described and illustrated herein, includes exposing the reactive layer 110 to a negative developer, such as a developer containing toluene.

[0071]

[0082] FIG. 3E shows a top view of a portion of the reactive layer 110 according to one or more embodiments described and illustrated herein. FIG. 3F shows a side cross-sectional view of a portion of the reactive layer 110 according to one or more embodiments described and illustrated herein. FIGS. 3E and 3F show the reactive layer 110 after the reactive layer has undergone a treatment process. FIG. 4C shows the first region 301 after the treatment process. The intermediate 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.

[0072]

[0083] After method 200 is completed, a metal layer can be deposited in trench 350 and reactive material 300 is removed. Thus, method 200 can be used to form circuits that include a metal layer of the desired shape determined by method 200.

[0073]

[0084] While method 200 is described using a positive photoresist process (e.g., method 200 makes the reacted material 320 more soluble), the same method 200 may be applied to a negative photoresist process. In these embodiments, the medium-dose region 312 becomes less soluble after exposure to a first wavelength of light, and a treatment process removes the remaining reactive layer 110. For example, the reactive layer 110 is exposed to toluene for about 30 seconds to about 300 seconds to remove the reactive layer 110 and leave the reacted material 320. Method 200 may also be performed as a dual-tone photolithography process that includes both a positive resist process and a negative resist process.

[0074]

[0085] While the method 200 described above includes different regions of the reactive layer 110 receiving light of two different wavelengths, other methods are contemplated. In one or more embodiments, the reactive layer 110 includes two or more different regions, each region including a different photoactive material. The different photoactive materials are active at different wavelengths of light. The entire reactive layer can be exposed to light of the different wavelengths, causing the materials in the reactive layer to react and form a desired pattern.

[0075]

[0086] 5A and 5B show cross-sectional side views of a portion of a workpiece 500 including a reactive layer 110 at various stages of processing, and FIG. 5C shows a top view of the portion of workpiece 500 shown in FIG. 5B, according to one or more embodiments described and illustrated herein. Workpiece 500 includes a reactive layer 110 including a reactive material disposed on a substrate 115, as shown in FIG. 5A. A method for patterning a layered structure on workpiece 500 can be performed in lithographic apparatus 100, as described and illustrated herein.

[0076]

[0087] In one or more embodiments, the reactive material includes one or more polymeric photoresist materials, one or more PAGs, and one or more PBGs. The PAGs are active or activated by light having a first wavelength, and the PBGs are active 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.

[0077]

[0088] In one or more embodiments, the polymeric photoresist material is or contains one or more polymer resins (e.g., poly-t-BOC). In one or more embodiments, the PAG is or contains one or more triflate compounds (e.g., iodonium triflate). In one or more embodiments, the PBG is or contains a cyanoacrylic acid chromophore and a bicyclic nitrogenous base. An example of a cyanoacrylic acid chromophore includes (E)-3-(2,2'-bithiophen-5-yl)-2-cyanoacrylic acid chromophore. An example of a bicyclic nitrogenous base can include 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD).

[0078]

[0089] The workpiece 500 is exposed to a first light 512 having a first wavelength and a second light 514 having a second wavelength, as depicted by the arrows in FIG. 5B. Upon exposure to the first light 512 at the first wavelength, a first pattern region 502 of reactive material is formed or otherwise created in the reactive layer 110 (FIG. 5A). The first pattern region 502 may be or include trenches, vias, contact vias, channels, and / or other openings, which may have any shape, size, geometric shape, or pattern. Similarly, upon exposure to the second light 514 at the second wavelength, a second pattern region 504 of reactive material is formed or otherwise created in the reactive layer 110 (FIG. 5A). The second pattern region 504 may be the negative of the first pattern region 502. In some embodiments, the first pattern region 502 remains unexposed to the second light 514 having the second wavelength, and the second pattern region 504 remains unexposed to the first light 512 having the first wavelength. The exposure of the first pattern region 502 and the second pattern region 504 to the first light 512 and the second light 514 occurs simultaneously with each other. For example, an acid is generated in one of the first pattern region 502 or the second pattern region 504 of the reactive material, and a base is generated in the other pattern region different from the pattern region containing the generated acid. In this manner, an acid is generated in the first pattern region 502 and a base is generated in the second pattern region 504. Alternatively, a base is generated in the first pattern region 502 and an acid is generated in the second pattern region 504.

[0079]

[0090] 5B, the acid generated from the PAG is shown as an o's numbered 522 in the first pattern region 502, and the base generated from the PBG is shown as an x's numbered 524 in the second pattern region 504. In other embodiments not shown, the acid generated from the PAG can be identified in the second pattern region 504, and the base generated from the PBG can be identified in the first pattern region 502.

[0080]

[0091] In either embodiment, a neutralized zone 508 is generated from the reaction of an acid and a base at the interface disposed between the first pattern region 502 and the second pattern region 504. The neutralized zone 508 contains one or more salts generated from the acid and the base at the interface of the pattern regions 502, 504. The neutralized zone 508 provides sharp, clean edges to features, such as between the pattern regions 502, 504, thereby providing improved resolution in the lithography processes described and illustrated herein compared to conventional lithography processes. The neutralized zone 508 provides a region between the forward reaction occurring in one region, such as the pattern region 502 or 504, and the blocking of the forward reaction occurring in an adjacent region. For example, the acid in the reactive material with the pattern region 502 or 504 removes protecting groups of the polymeric photoresist material, while the base in the reactive material in the other pattern region 502 or 504 blocks (prevents) the deprotection of the protecting groups of the polymeric photoresist material.

[0081]

[0092] As described and illustrated in step 230, the workpiece 500 including the first pattern area 502 and the second pattern area 504 can be exposed to a treatment process. The first pattern area 502 and the second pattern area 504 are exposed to one or more developers during the treatment process. In one or more embodiments, the first pattern area 502 of reactive material is removed and the second pattern area 504 of reactive material is maintained during the treatment process. The developer may be a positive developer containing one or more developer bases. Alternatively, the developer may be a negative developer containing one or more developer acids.

[0082]

[0093] In some embodiments, a method of patterning a laminate structure includes simultaneously exposing a first pattern region 502 of reactive material to a first light 512 at a first wavelength and a second pattern region 504 of reactive material to a second light 514 at a second wavelength to generate an acid in the first pattern region 502 of reactive material and a base in the second pattern region 504 of reactive material, and generating a neutralization zone 508 from the generated acid and the generated base at the interface between the first pattern region 502 and the second pattern region 504. The method further includes exposing the first pattern region 502 and the second pattern region 504 of reactive material to a developer (e.g., a positive developer) during the treatment process, such that the first pattern region 502 of reactive material is removed and the second pattern region 504 of reactive material is maintained during the treatment process. In other examples, the developer is a negative developer, such that the first pattern region 502 of reactive material is maintained and the second pattern region 504 of reactive material is removed during the treatment process.

[0083]

[0094] In one or more embodiments, the reactive material in the reactive layer includes one or more polymeric photoresist materials, one, two, or more cross-linking inhibitors, and optionally one or more quenchers. In some examples, the reactive material includes one or more polymeric photoresist materials, a first cross-linking inhibitor, and a second cross-linking inhibitor. In other examples, the reactive material includes one or more polymeric photoresist materials, a cross-linking inhibitor, and one or more quenchers.

[0084]

[0095] In one or more embodiments, a method for patterning a laminate structure includes disposing a reactive material on the laminate structure and / or substrate. The reactive material includes a polymeric photoresist material, a first crosslinking inhibitor, and a second crosslinking inhibitor. The first crosslinking inhibitor is active at a first wavelength, and the second crosslinking inhibitor is active at a second wavelength different from the first wavelength. The method includes simultaneously exposing a first pattern region of the reactive material to first light at a first wavelength and a second pattern region of the reactive material to second light at a second wavelength; generating a first activated crosslinking inhibitor in the first pattern region of the reactive material and a second activated crosslinking inhibitor in the second pattern region of the reactive material simultaneously; and generating a neutralization zone from the first activated crosslinking inhibitor and the second activated crosslinking inhibitor at an interface between the first pattern region and the second pattern region.

[0085]

[0096] 6 shows a top view of a portion of a workpiece 600 including reactive layer 110 at one processing stage, according to one or more embodiments described and illustrated herein. Workpiece 600 is similar to workpiece 500, except that workpiece 600 further includes a third pattern region 506 of reactive material that is exposed to both the first and second light, as shown in FIG. 6. Third pattern region 506 may be a cut surface or region on workpiece 600. Thus, when the reactive material in first pattern region 502 is removed during the treatment process of step 230, the reactive material in third pattern region 506 may remain on workpiece 600 along with the reactive material in second pattern region 504.

[0086]

[0097] In one or more embodiments, the workpiece 600 includes a reactive layer 110 including a reactive material disposed on a laminate structure or substrate. The reactive material includes one or more polymeric photoresist materials, one or more PAGs, and one or more PBGs. The PAGs are active at a first wavelength, and the PBGs are active at a second wavelength different from the first wavelength. The method includes simultaneously exposing a first pattern region 502 of the reactive material to a first light at a first wavelength and a second pattern region 504 of the reactive material to a second light at a second wavelength, and exposing a third pattern region 506 of the reactive material to the first light at the first wavelength and the second light at a second wavelength. In some embodiments, the third pattern region 506 is part of the first pattern region 502, as shown in FIG. 6 . In other embodiments, the third pattern region 506 is part of the second pattern region 504 (not shown). In a further embodiment, the third pattern region 506 is part of both the first pattern region 502 and the second pattern region 504 (not shown).

[0087]

[0098] The method further includes generating an acid from the PAG in the first pattern region 502 of the reactive material while simultaneously generating a base from the PBG in the second pattern region 504 and the third pattern region 506 of the reactive material. Neutralization zones 508 are disposed at the interfaces between the first pattern region 502 and the second pattern region 504 and between the first pattern region 502 and the third pattern region 506. In one or more embodiments, the third pattern region 506 is exposed to the first light having the first wavelength and the second light having the second wavelength while the first pattern region 502 remains unexposed to the second light having the second wavelength and the second pattern region 504 remains unexposed to the first light having the first wavelength.

[0088]

[0099] As described above, a lithographic apparatus, a patterning system, and a 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 generation of a lithographic pattern. The lithographic apparatus includes a patterning system and an optical system. The lithographic apparatus uses multiple wavelengths of light in conjunction with the image-forming device to form multiple different color images and / or patterns on the reactive layer. The patterning method includes exposing the reactive layer to multiple different wavelength patterns of light. The reactive layer responds differently to the different wavelengths of light, allowing for the formation of multiple color images and / or one or more composite images in a single lithographic step.

[0089]

[0100] The methods and apparatus disclosed herein require a single lithography step, which produces a net composite image, whereas in other situations multiple lithography steps and multiple masks would have been required. Furthermore, the use of an imaging device reduces the need to align multiple masks, thereby reducing lithography time.

[0090]

[0101] While the foregoing description is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope of the disclosure, the scope of which is determined by the following claims. All documents set forth herein are incorporated by reference, including any priority documents and / or testing procedures, to the extent not inconsistent with this text. As is apparent from the foregoing summary and specific embodiments, while forms of the present disclosure have been illustrated and described, various modifications may be made without departing from the spirit and scope of the present disclosure. Accordingly, no limitation of the present disclosure is intended. Similarly, for purposes of U.S. law, the word "comprising" is considered synonymous with the word "including." Similarly, when a composition, element, or group of elements is preceded by the transitional phrase "comprising," it is understood that similar compositions or group of elements with the transitional phrase "consisting essentially of," "consisting of," "selected from the group of consisting of," or "is" preceding the recitation of the composition, element, or multiple elements is also contemplated, and vice versa.

[0091]

[0102] As used herein, the term "about" refers to a + / - 10% variation from the nominal value. It is understood that any value provided herein may include such a variation.

[0092]

[0103] Certain embodiments and features are described using a set of upper numerical limits and a set of lower numerical limits. It should be recognized that ranges including any two value combinations (e.g., any lower value with any upper value, any two lower values, and / or any two upper values) are contemplated unless otherwise indicated. The claims set forth certain lower limits, upper limits, and ranges.

Claims

1. 1. A method for patterning a layered structure, comprising: depositing a reactive layer over the laminate structure; and exposing the reactive layer, which comprises a reactive material comprising first regions and second regions, to multiple wavelengths of light through an imaging device, wherein the reactive material has a first photoacid generator (PAG), a first photobase generator (PBG), and a second PBG; Including, exposing the reactive layer to generating a first light image at a first wavelength in the first region of the reactive layer, wherein the first PAG and the first PBG are each activated at the first wavelength; generating a second light image at a second wavelength in the second region of the reactive layer, the first light image and the second light image having different doses, and at the second wavelength, the second PBG is activated; A method comprising:

2. The reactive layer is exposed through the imaging device, and the imaging device comprises: a first device region capable of generating the first light image at the first wavelength that is projected onto the first region of the reactive layer; and a second device region capable of generating the second light image at the second wavelength that is projected onto the second region of the reactive layer; The method of claim 1 , comprising:

3. The method of claim 1 , wherein the image-forming device includes a photomask, and the first light image and the second light image are projected through the photomask.

4. 2. The method of claim 1, wherein the image forming device includes 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.

5. 10. The method of claim 1, wherein the reactive layer comprises a photoresist and the imaging device comprises a spatial modulator having one or more digital micromirror devices (DMDs).

6. The method of claim 1 , wherein exposing the first area and the second area occurs simultaneously.

7. 10. The method of claim 1, wherein exposing the first and second regions is performed sequentially, and exposing the first and second regions is repeated one or more times.

8. The method of claim 1 , wherein the first region and the second region at least partially overlap.

Images