Photoresist underlayer materials and related methods

Abstract

The invention provides photoresist underlayer materials and related methods. A semiconductor device may be fabricated using a multi-layer photoresist formed from one or more materials that reduce the likelihood that residual material remains in the multi-layer photoresist and / or the amount of the residual material. The photoresist underlayer of the multilayer photoresist includes a polymer having a highly uniform distribution of polar group monomers. Additionally and / or alternatively, the photoresist underlayer comprises a polymer comprising a backbone and a plurality of side chains coupled to the backbone. The side chain comprises an acid generator component. As the acid generator component is coupled with the main chain of the polymer through the side chain, the acid generator component is not diffused into the photoresist layer in an uncontrolled manner; the acid generated by the acid generator component upon exposure to radiation is thus concentrated in a uniform manner below the bottom of the photoresist layer and enables the bottommost portion of the photoresist layer to be developed and removed.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 582,403, entitled “PHOTORESIST UNDERLAYER MATERIALS AND ASSOCIATED METHODS,” filed on September 13, 2023. The disclosure of the prior application is considered a part of and incorporated by reference into this patent application. Technical Field

[0003] The present application relates to photoresist bottom layer materials and related methods. Background Art

[0004] As semiconductor device sizes continue to shrink, some lithography techniques are limited by optics, which results in resolution issues and reduced lithography performance. In contrast, extreme ultraviolet (EUV) lithography can achieve much smaller semiconductor device sizes and / or feature sizes by using reflective optics and radiation wavelengths of approximately 13.5 nanometers or less. Summary of the invention

[0005] In some embodiments of the present invention, a method is provided, comprising:

[0006] forming a photoresist bottom layer over the substrate,

[0007] wherein the photoresist bottom layer comprises a polymer and an acid generator component;

[0008] performing a processing operation on the photoresist bottom layer,

[0009] wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation;

[0010] forming a photoresist layer over the photoresist bottom layer after the processing operation;

[0011] exposing the photoresist layer to radiation to form a pattern in the photoresist layer,

[0012] wherein the acid generator component in the photoresist bottom layer generates an acid based on at least one of the processing operation or the radiation, the acid causing the pattern to be formed in the photoresist layer; and

[0013] The pattern in the photoresist layer is developed.

[0014] In some other embodiments of the present invention, a method is provided, comprising:

[0015] forming a photoresist bottom layer over the substrate,

[0016] The photoresist bottom layer comprises:

[0017] a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains;

[0018] forming a photoresist layer over the photoresist bottom layer;

[0019] exposing the photoresist layer to radiation to form a pattern in the photoresist layer,

[0020] wherein the acid generator component in the photoresist bottom layer reacts with radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; and

[0021] The pattern in the photoresist layer is developed.

[0022] In some other embodiments of the present invention, a method is provided, comprising:

[0023] forming a photoresist bottom layer over the substrate,

[0024] The photoresist bottom layer comprises:

[0025] a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains;

[0026] performing a processing operation on the photoresist bottom layer,

[0027] wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation;

[0028] forming a photoresist layer over the photoresist bottom layer after the processing operation;

[0029] exposing the photoresist layer to radiation to form a pattern in the photoresist layer,

[0030] wherein the acid generator component in the photoresist bottom layer reacts with radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; and

[0031] The pattern in the photoresist layer is developed. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] When read in conjunction with the accompanying drawings, various aspects of the present disclosure can be best understood from the following detailed description. It should be noted that, in accordance with standard practice in the industry, various features are not drawn to scale. In fact, for the sake of clarity of discussion, the size of the various features may be arbitrarily increased or reduced.

[0033] Figure 1 is a diagram of an exemplary environment in which the systems and / or methods described herein may be implemented.

[0034] Figure 2A and Figure 2B is a diagram of an exemplary implementation of an exposure tool described herein.

[0035] FIG. 3A to FIG. 3F is a diagram of an exemplary implementation of forming a multilayer photoresist as described herein.

[0036] FIG. 4A to FIG. 4C is a diagram of an exemplary implementation of exposing a multilayer photoresist described herein to radiation to form a pattern in the multilayer photoresist.

[0037] FIG. 5A to FIG. 5C is a diagram of an exemplary implementation of developing a pattern formed in a photoresist layer of a multi-layer photoresist described herein.

[0038] Fig. 6A and Figure 6B is a diagram of examples of materials that can be used for the R1 component and the crosslinking group component described herein.

[0039] 7A to 7C is a diagram of examples of materials that can be used for the acid generator component described herein.

[0040] FIG. 8A to FIG. 8C is a diagram of an exemplary implementation of a multilayer photoresist as described herein.

[0041] Fig. 9 is a diagram of an exemplary implementation of a photoresist bottom layer as described herein.

[0042] Fig.10 is a diagram of an exemplary implementation of a photoresist bottom layer as described herein.

[0043] Fig.11 is a diagram of an exemplary implementation of a photoresist bottom layer as described herein.

[0044] Fig.12is a diagram of exemplary components of devices described herein.

[0045] Fig.13 is a flow chart of an exemplary process associated with forming a multi-layer photoresist on a semiconductor substrate as described herein.

[0046] Fig.14 is a flow chart of an exemplary process associated with forming a multi-layer photoresist on a semiconductor substrate as described herein. DETAILED DESCRIPTION

[0047] The following disclosure provides many different embodiments or examples for realizing the different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. Of course, these are merely examples and are not intended to be limiting. For example, forming a first feature above or on a second feature in the following description may include an embodiment in which the first feature and the second feature are formed to be in direct contact, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature so that the first feature and the second feature may not be in direct contact. In addition, the present disclosure may repeat figure numerals and / or letters in various examples. This repetition is for the purpose of simplicity and clarity, and does not itself dictate the relationship between the various embodiments and / or configurations discussed.

[0048] Further, for ease of description, spatially relative terms such as "below," "below," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or feature to another element or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly.

[0049] One of the problems with extreme ultraviolet (EUV) lithography is that most materials are highly absorbing of EUV radiation due to its short wavelength. Therefore, only a small portion of the EUV radiation generated by the EUV source is ultimately available for the substrate to be patterned. Increasing the exposure dose of EUV radiation can result in reduced line width roughness (LWR) and / or reduced local critical dimension uniformity (LCDU) in the features formed on the substrate. Therefore, due to the strictly optimized exposure dose (E op ) parameters, semiconductor manufacturers may not be able to simply increase the exposure dose of their EUV lithography processes.

[0050] Multilayer photoresist can improve the sensitivity to incident light in the EUV wavelength range. However, there are some disadvantages in multilayer photoresist. For example, multilayer photoresist may include one or more photoresist underlayers, and a photoresist layer on the one or more photoresist underlayers. The photoresist underlayer may include polar groups to promote adhesion to the photoresist layer, and the photoresist underlayer may include non-uniformly distributed polar groups (e.g., hydroxyl groups). The region with high concentration of polar groups can more easily absorb and aggregate the photodecomposable alkali (photo-decomposable base, PDB) material in the photoresist layer, resulting in a region with high concentration of PDB material in the photoresist layer. High concentration of PDB material can prevent these regions of the photoresist layer from being fully exposed, developed and removed, which may cause residual material to remain in these regions (referred to as bottom scum or photoresist scum). The residual material may reduce the effectiveness of subsequent semiconductor processing operations using the multi-layer photoresist (e.g., may cause a reduction in etch depth in an etching operation, may cause a reduction in ion implantation coverage). This may increase the likelihood of defects forming in semiconductor devices on the semiconductor wafer on which the photoresist is formed.

[0051] As another example, the photoresist bottom layer may include an acid-generating component (e.g., a photo acid generator (PAG), a thermal acid generator (TAG)) that diffuses into the photoresist layer and generates acid when exposed to EUV radiation. The acid acts as a catalyst for causing a chemical reaction in the photoresist layer. The chemical reaction changes (e.g., increases, decreases) the solubility of the exposed portion of the photoresist layer, thereby enabling a multi-layer photoresist to be patterned based on exposure to EUV radiation. However, the acid-generating component may diffuse into the photoresist layer in an uneven manner, which may prevent or reduce the likelihood of residual material in the photoresist layer being removed. The uneven distribution of the acid-generating component may result in an area with a low concentration of acid at the bottom of the photoresist layer. Therefore, the amount of acid generated at the bottom of the photoresist layer may be insufficient to develop and remove the entire thickness of the photoresist layer.

[0052] In some implementations described herein, a semiconductor device can be fabricated using a multilayer photoresist. The multilayer photoresist is formed of one or more materials that reduce the likelihood and / or amount of residual material remaining in a photoresist layer of the multilayer photoresist after the photoresist layer is exposed to EUV radiation and developed. In some implementations, a photoresist bottom layer of the multilayer photoresist includes a polymer having a highly uniform distribution of polar group monomers.

[0053] In some implementations, the photoresist bottom layer of the multilayer photoresist comprises a polymer, the polymer comprising a main chain and a plurality of side chains coupled to the main chain. In particular, the side chain comprises an acid generator component, such as PAG and / or TAG. Since the acid generator component is coupled to the main chain of the polymer through the side chain, rather than being diffused into the photoresist layer uncontrollably, the acid generated by the acid generator component when exposed to EUV radiation is gathered in a uniform manner below the bottom of the photoresist layer and enables the bottommost portion of the photoresist layer to be developed and removed. This reduces the possibility of residual photoresist material remaining in the photoresist layer, which can reduce LCDU and / or reduce LWR in features formed in semiconductor devices using multilayer photoresists. Reduced LWR and / or reduced LCDU can enable features to be formed into smaller sizes and / or increased uniformity, thereby increasing the yield of semiconductor structures formed on semiconductor devices.

[0054] Figure 1 1 is a diagram of an exemplary environment 100 in which the systems and / or methods described herein may be implemented. Figure 1 As shown, the exemplary environment 100 may include a plurality of semiconductor processing tools 102 to 108 and a wafer / die transport tool 110. The plurality of semiconductor processing tools 102 to 108 may include a deposition tool 102, an exposure tool 104, a developer tool 106, an etching tool 108, and / or another type of semiconductor processing tool. In particular, the tools included in the exemplary environment 100 may be included in a semiconductor clean room, a semiconductor foundry, a semiconductor processing facility, and / or a manufacturing facility.

[0055] The deposition tool 102 is a semiconductor processing tool that includes a semiconductor processing chamber and one or more devices capable of depositing various types of materials onto a substrate. In some implementations, the deposition tool 102 includes a spin coating tool capable of depositing a photoresist layer on a substrate (e.g., a wafer). In some implementations, the deposition tool 102 includes a chemical vapor deposition (CVD) tool, such as a plasma-enhanced CVD (PECVD) tool, a high-density plasma CVD (HDP-CVD) tool, a sub-atmospheric CVD (SACVD) tool, a low-pressure CVD (LPCVD) tool, an atomic layer deposition (ALD) tool, a plasma-enhanced atomic layer deposition (PEALD) tool, or another type of CVD tool. In some implementations, the deposition tool 102 includes a physical vapor deposition (PVD) tool, such as a sputtering tool or another type of PVD tool. In some implementations, the deposition tool 102 includes an epitaxial tool configured to form layers and / or regions of a device by epitaxial growth. In some implementations, the exemplary environment 100 includes multiple types of deposition tools 102.

[0056] The exposure tool 104 is a semiconductor processing tool capable of exposing a photoresist layer to a radiation source, such as an ultraviolet light (UV) source (e.g., a deep UV light source, an extreme UV light (EUV) source, and / or the like), an x-ray source, an electron beam (e-beam) source, and / or the like. The exposure tool 104 may expose the photoresist layer to the radiation source to transfer a pattern from a photomask to the photoresist layer. The pattern may include one or more semiconductor device layer patterns for forming one or more semiconductor devices, may include patterns for forming one or more structures of a semiconductor device, may include patterns for etching various portions of a semiconductor device, and / or the like. In some implementations, the exposure tool 104 includes a scanner, a stepper, or a similar type of exposure tool.

[0057] The developer tool 106 is a semiconductor processing tool capable of developing a photoresist layer that has been exposed to a radiation source to develop a pattern transferred to the photoresist layer from the exposure tool 104. In some implementations, the developer tool 106 develops the pattern by removing unexposed portions of the photoresist layer. In some implementations, the developer tool 106 develops the pattern by removing exposed portions of the photoresist layer. In some implementations, the developer tool 106 develops the pattern by using a chemical developer to dissolve the exposed or unexposed portions of the photoresist layer.

[0058] The etching tool 108 is a semiconductor processing tool capable of etching various types of materials of a substrate, wafer, or semiconductor device. For example, the etching tool 108 may include a wet etching tool, a dry etching tool, etc. In some implementations, the etching tool 108 includes a chamber filled with an etchant, and a substrate is placed in the chamber for a specific period of time to remove a specific amount of one or more portions of the substrate. In some implementations, the etching tool 108 may use plasma etching or plasma assisted etching to etch one or more portions of the substrate, which may involve using an ionized gas to etch the one or more portions isotropically or directionally.

[0059] The wafer / die transporter 110 includes a mobile robot, a robotic arm, a tram or rail car, an overhead hoist transport (OHT) system, an automated material handling system (AMHS), and / or another type of device configured to transport substrates and / or semiconductor devices between semiconductor processing tools 102 to 108, to transport substrates and / or semiconductor devices between processing chambers of the same semiconductor processing tool, and / or to transport substrates and / or semiconductor devices to and from other locations (e.g., wafer racks, storage rooms), etc. In some implementations, the wafer / die transporter 110 can be a programmed device configured to travel a specific path and / or can operate semi-autonomously or autonomously. In some implementations, the exemplary environment 100 includes multiple wafer / die transporters 110.

[0060] For example, in particular, the wafer / die transporter 110 may be included in a cluster tool or another type of tool including multiple processing chambers, and may be configured to transport substrates and / or semiconductor devices between multiple processing chambers, between a processing chamber and a buffer, between a processing chamber and an interface tool (e.g., an equipment front end module (EFEM)), and / or between a processing chamber and a transport carrier (e.g., a front opening unified pod (FOUP)). In some implementations, the wafer / die transporter 110 may be included in a multi-chamber (or cluster) deposition tool 102, which may include a pre-cleaning chamber (e.g., for cleaning or removing oxides, oxidation and / or other types of contaminants or byproducts from substrates and / or semiconductor devices) and multiple types of deposition chambers (e.g., chambers for depositing different types of materials, chambers for performing different types of deposition operations). In these implementations, as described herein, the wafer / die transport vehicle 110 is configured to transport substrates and / or semiconductor devices between processing chambers of the deposition tool 102 without breaking or removing the vacuum (or at least partial vacuum) between the processing chambers and / or between processing operations in the deposition tool 102.

[0061] In some implementations, one or more of the semiconductor processing tools 102 to 108 and / or the wafer / die transport 110 can be used to perform one or more semiconductor processing operations described herein. For example, one or more of the semiconductor processing tools 102 to 108 and / or the wafer / die transport 110 can be used to form a photoresist bottom layer over a substrate, wherein the photoresist bottom layer comprises a polymer and an acid generator component; perform a processing operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the processing operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the processing operation; after the processing operation, form a photoresist layer over the photoresist bottom layer; expose the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; and develop the pattern in the photoresist layer.

[0062] As another example, one or more of the semiconductor processing tools 102 to 108 and / or the wafer / die transport tool 110 can form a photoresist bottom layer over a substrate, wherein the photoresist bottom layer comprises a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains; form a photoresist layer over the photoresist bottom layer; expose the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid that causes a pattern to be formed in the photoresist layer; and develop the pattern in the photoresist layer.

[0063] As another example, one or more of the semiconductor processing tools 102 to 108 and / or the wafer / die transport tool 110 can form a photoresist bottom layer above a substrate, wherein the photoresist bottom layer includes a polymer backbone, multiple acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the multiple acid generator component side chains; perform a processing operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the processing operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the processing operation; after the processing operation, form a photoresist layer above the photoresist bottom layer; expose the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid, and the acid causes the pattern to be formed in the photoresist layer; and develop the pattern in the photoresist layer.

[0064] In some implementations, one or more of the semiconductor processing tools 102-108 and / or the wafer / die transport tool 110 may be used to perform operations particularly in conjunction with FIG. 3A to FIG. 3F , FIG. 4A to FIG. 4C , Figure 5A , Figure 5B , FIG. 8A to FIG. 8C , Figures 9 to 11 , and / or Figure 13 to Figure 14 One or more semiconductor processing operations.

[0065] Figure 1 The number and arrangement of devices shown in the figure are provided as one or more examples. In practice, there may be Figure 1 Additional devices, fewer devices, different devices, or differently arranged devices than those shown in . In addition, Figure 1 Two or more of the devices shown in FIG. 1 may be implemented in a single device, or Figure 1The single device shown in can be implemented as multiple distributed devices. Additionally or alternatively, a set of devices (eg, one or more devices) of exemplary environment 100 can perform one or more functions described as being performed by another set of devices of exemplary environment 100.

[0066] Figure 2A and Figure 2B is a diagram of an exemplary implementation 200 of the exposure tool 104 described herein. The exposure tool 104 includes an EUV lithography system, or another type of lithography system configured to transfer a pattern onto a semiconductor substrate using mirror-based optics. The exposure tool 104 can be configured for use in a semiconductor processing environment, such as a semiconductor foundry or a semiconductor manufacturing facility.

[0067] like Figure 2A As shown, exposure tool 104 includes radiation source 202 and exposure system 204. Radiation source 202 (e.g., an EUV radiation source or another type of radiation source) is configured to generate radiation 206, such as EUV radiation and / or another type of electromagnetic radiation (e.g., light). Exposure system 204 (e.g., an EUV scanner or another type of exposure tool) is configured to focus radiation 206 onto a reflective reticle 208 (or a photomask) so that a pattern is transferred from the reticle 208 to a semiconductor substrate 210 using radiation 206.

[0068] The radiation source 202 includes a container 212 and a collector 214 in the container 212. The collector 214 includes a curved mirror configured to collect radiation 206 generated by the radiation source 202 and focus the radiation 206 toward an intermediate focus 216. The radiation 206 is generated by a plasma generated by droplets 218 (e.g., tin (Sn) droplets or another type of droplet) exposed to a laser beam 220. The droplets 218 are provided across the front of the collector 214 by a droplet generator (DG) head 222. The DG head 222 is pressurized to provide a fine and controlled output of the droplets 218.

[0069] A laser source, such as a pulsed carbon dioxide (CO2) laser, generates a laser beam 220. The laser beam 220 is provided (e.g., by a beam delivery system to a focusing lens) such that the laser beam 220 is focused through a window 224 of the collector 214. The laser beam 220 is focused onto the droplets 218 generating the plasma. The plasma generates plasma emissions, some of which are radiation 206. The laser beam 220 is pulsed in a timed manner synchronized with the flow of the droplets 218 from the DG head 222.

[0070] The exposure system 204 includes an illuminator 226 and a projection optics box (POB) 228. The illuminator 226 includes a plurality of mirrors configured to focus and / or direct the radiation 206 onto the reticle 208 so as to illuminate the pattern on the reticle 208. The plurality of mirrors include, for example, a mirror 230a and a mirror 230b. The mirror 230a includes a field facet mirror (FFM) or another type of mirror including a plurality of field facets. The mirror 230b includes a pupil facet mirror (PFM) or another type of mirror also including a plurality of pupil facets. The facets of the mirrors 230a and 230b are arranged to focus, polarize and / or otherwise tune the radiation 206 from the radiation source 202 to increase the uniformity of the radiation 206 and / or to increase a particular type of radiation component (e.g., transverse electric (TE) polarized radiation, transverse magnetic (TM) polarized radiation). Another mirror 232 (eg, a relay mirror) is included to direct radiation 206 from illuminator 226 onto reticle 208 .

[0071] The projection optics box 228 includes a plurality of mirrors configured to project the radiation 206 onto the semiconductor substrate 210 after modifying the radiation 206 based on the pattern of the reticle 208. The plurality of mirrors include, for example, mirrors 234a through 234f. In some implementations, the mirrors 234a through 234f are configured to focus or reduce the radiation 206 into an exposure field, which may include one or more die regions on the semiconductor substrate 210.

[0072] The exposure system 204 includes a wafer stage 236 (e.g., a substrate stage) configured to support a semiconductor substrate 210. In addition, the wafer stage 236 is configured to move (or step) the semiconductor substrate 210 through a plurality of exposure fields as the radiation 206 transfers a pattern from the reticle 208 to the semiconductor substrate 210. The wafer stage 236 is included in a bottom module 238 of the exposure system 204. The bottom module 238 includes a removable subsystem of the exposure system 204. The bottom module 238 can be slid out of the exposure tool 104 and / or can be otherwise removed from the exposure system 204 to enable cleaning and inspection of the wafer stage 236 and / or components of the wafer stage 236. The bottom module 238 isolates the wafer stage 236 from other areas in the exposure system 204 to reduce and / or minimize contamination of the semiconductor substrate 210. Additionally, the bottom module 238 can provide physical isolation for the wafer stage 236 by reducing the transfer of vibrations (e.g., vibrations in the semiconductor processing environment in which the exposure tool 104 is located, vibrations in the exposure tool 104 during operation of the exposure tool 104) to the wafer stage 236, and thus to the semiconductor substrate 210. This reduces movement and / or disturbance of the semiconductor substrate 210, which reduces the likelihood that vibrations may cause pattern misalignment.

[0073] Exposure system 204 also includes reticle stage 240 configured to support and / or secure reticle 208. Furthermore, reticle stage 240 is configured to move or slide the reticle through radiation 206 such that reticle 208 is scanned by radiation 206. In this manner, a pattern that is larger than the field or beam of radiation 206 may be transferred to semiconductor substrate 210.

[0074] The exposure tool 104 includes a laser source 242. The laser source 242 is configured to generate a laser beam 220. The laser source 242 may include a CO2-based laser source or another type of laser source. Since the wavelength of the laser beam generated by the CO2-based laser source is in the infrared (IR) region, the laser beam can be highly absorbed by tin, which enables the CO2-based laser source to achieve high power and energy for pumping tin-based plasma. In some implementations, the laser beam 220 includes multiple types of laser beams generated by the laser source 242 using a multi-pulse technique (or a multi-stage pumping technique), wherein the laser source 242 generates a pre-pulse laser beam and a main pulse laser beam to achieve greater heating efficiency of the tin (Sn)-based plasma, thereby improving the conversion efficiency.

[0075] In an exemplary exposure operation (e.g., EUV exposure operation), the DG head 222 provides a stream of droplets 218 across the front of the collector 214. The laser beam 220 contacts the droplets 218, which causes plasma to be generated. The laser source 242 generates and provides a pre-pulse laser beam toward a target droplet in the stream of droplets 218, and the pre-pulse laser beam is absorbed by the target droplet. This transforms the target droplet into a disk or mist. Subsequently, the laser source 242 provides a main pulse laser beam with greater intensity and energy toward the disk-shaped target or target mist. Here, the atoms of the target are neutralized and ions are generated by heat flux and shock waves. The main pulse laser beam pumps the ions to a higher charge state, which causes the ions to emit radiation 206 (e.g., EUV light).

[0076] Radiation 206 is collected by collector 214 and directed out of container 212 and into exposure system 204 toward mirror 230a of illuminator 226. Mirror 230a reflects radiation 206 onto mirror 230b, which reflects radiation 206 toward reticle 208 onto mirror 232. Radiation 206 is modified by the pattern in reticle 208. In other words, radiation 206 is reflected from reticle 208 based on the pattern of reticle 208. Reflective reticle 208 directs radiation 206 toward mirror 234a in projection optics box 228, which reflects radiation 206 onto mirror 234b. Radiation 206 continues to be reflected and reduced by mirrors 234c through 234f in projection optics box 228. Mirror 234f reflects radiation 206 onto semiconductor substrate 210, causing the pattern of reticle 208 to be transferred onto semiconductor substrate 210. The above-described exposure operations are examples, and exposure tool 204 may operate according to other EUV techniques and radiation paths including a greater number of mirrors, a lesser number of mirrors, and / or mirrors in different configurations.

[0077] Figure 2B The operating range 244 of the exposure tool 104 is shown, wherein the LWR 246 depends on the exposure energy dose (E op ) 248. The absorption of EUV photons of radiation 206 by the photoresist may be low because EUV photons are more easily absorbed than deep UV radiation. Figure 2A As a result, fewer EUV photons reach the photoresist on the semiconductor substrate 210 than deep UV radiation, resulting in a low LWR 246 of the pattern formed in the photoresist on the semiconductor substrate 210. The EUV photons of the exposure tool 104 may be increased. op 248, thereby increasing the amount of EUV photons that ultimately enter the photoresist on the semiconductor substrate 210. Although this reduces the LWR 246 in the pattern formed in the photoresist, increasing the EUV photons will cause the photoresist to be more resistant to UV radiation. op248 increases the power consumption of the exposure tool 104 and reduces the operating efficiency of the exposure tool 104. On the other hand, E can be reduced at the expense of reducing EUV photon absorption and increasing LWR 246. op 248 to reduce power consumption.

[0078] The photoresist materials and techniques described herein enable patterns formed in a photoresist on a semiconductor substrate 210 to be formed with relatively low E op 248(in Figure 2B The photoresist material described herein comprises a chemically amplified reaction (CAR) photoresist material. As described herein, the photoresist material can be used to form a multilayer photoresist including a photoresist bottom layer. The photoresist bottom layer may include a polymer having a highly uniform distribution of polar group monomers. Additionally and / or alternatively, the photoresist bottom layer comprises a polymer comprising a main chain and a plurality of side chains coupled to the main chain. The side chains comprise an acid generator component. Since the acid generator component is coupled to the main chain of the polymer through the side chains, rather than diffusing uncontrollably into the photoresist layer, the acid generated by the acid generator component when exposed to radiation 206 is gathered in a uniform manner below the bottom of the photoresist layer and enables the bottommost portion of the photoresist layer to be developed and removed. This reduces the likelihood that residual photoresist material will remain in the photoresist layer, which can reduce LCDU in features formed in a semiconductor device using multiple layers of photoresist and / or can reduce LWR 246. Reduced LWR 246 and / or reduced LCDU can enable features to be formed with smaller sizes and / or increased uniformity, thereby increasing the yield of semiconductor structures formed on semiconductor substrate 210.

[0079] As mentioned above, Figure 2A and Figure 2B are provided as examples. Other examples can be found in the Figure 2A and Figure 2B Different than described.

[0080] FIG. 3A to FIG. 3F 3 is a diagram of an exemplary implementation 300 of forming a multilayer photoresist as described herein. The exemplary implementation 300 includes an example of using the multilayer photoresist to form the multilayer photoresist over a layer 302 on a semiconductor substrate 210 to be patterned. For example, the layer 302 can be etched using an etching tool 108 based on a pattern formed in the multilayer photoresist. Additionally and / or alternatively, the semiconductor substrate 210 can be processed based on the pattern formed in the multilayer photoresist.

[0081] Steering Figure 3A , a semiconductor substrate 210 may be positioned in a process chamber of a deposition tool 102. The semiconductor substrate 210 includes a semiconductor die substrate, a semiconductor wafer, or another type of substrate in which and / or on which a semiconductor device may be formed. In some implementations, the semiconductor substrate 210 is formed of silicon (Si), a material containing silicon, a Group III to Group V compound semiconductor material (e.g., gallium arsenide (GaAs)), silicon on insulator (SOI), or another type of semiconductor material.

[0082] Deposition tool 102 may be used to form layer 302 above and / or on semiconductor substrate 210. Layer 302 may be etched to form various types of semiconductor devices, openings, trenches, vias, interconnects, contacts, and / or other types of semiconductor structures. Layer 302 may include a dielectric layer, a metallization layer, a hard mask layer, and / or another type of semiconductor layer.

[0083] like Figure 3B As shown, a photoresist bottom layer 304 of the multi-layer photoresist is formed over the semiconductor substrate 210 (e.g., over the layer 302 on the semiconductor substrate 210). The deposition tool 102 can be used to deposit the photoresist bottom layer 304 using various PVD techniques, CVD techniques, and / or ALD techniques (e.g., spin coating, sputtering, PECVD, HDP-CVD, SACVD, and / or PEALD, among others). The photoresist bottom layer 304 includes a middle layer (ML), a bottom layer (BL), a bottom anti-reflective coating (BARC), and / or another type of bottom layer.

[0084] In some implementations, the photoresist bottom layer 304 is formed to a thickness ranging from about 5 angstroms to about 500 angstroms (in Figure 3B The photoresist bottom layer 304 may be formed to have a thickness outside of this range (indicated as dimension D1 in the figure) to meet one or more etching parameters for etching layer 302 (e.g., such as a target depth and / or a target width of a trench or opening to be etched into layer 302). If the photoresist bottom layer 304 is formed to have a thickness outside of this range, the photoresist bottom layer may not provide sufficient chemical reactants to other layers of the multi-layer photoresist to allow patterning of the multi-layer photoresist. However, other values ​​of the thickness of the photoresist bottom layer 304 and ranges other than about 5 angstroms to about 500 angstroms are also within the scope of the present disclosure.

[0085] like Figure 3BAs further shown in , the photoresist bottom layer 304 includes a polymer material 306. The polymer material 306 includes a polymer backbone 308, a cross-linking group component 310 coupled to the polymer backbone 308 through an R1 component, and an acid generator component 312. The polymer chain 308 may include an oligomer, a copolymer, and / or another type of polymer including a polar group (e.g., a hydroxyl group and / or another type of polar group). The polymer chain 308 may include other elements, such as, in particular, carbon (C), silicon (Si), and / or other elements. In some implementations, the polymer chain 308 includes, in particular, a phenolic resin, a poly(norbornene)-co-maleic anhydride (COMA) polymer, a poly(4-hydroxystyrene) (PHS) polymer, a phenol-formaldehyde (hakelite) polymer, a polyethylene (PE) polymer, a polypropylene (PP) polymer, a polycarbonate polymer, a polyester polymer, and / or an acrylate-based polymer, such as a poly(methyl methacrylate) (PMMA) polymer or a poly(methacrylic acid) (PMAA). In some implementations, the polymer chain 308 is cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and / or branched or unbranched. In some implementations, the polymer chain 308 includes a hydrocarbon group (e.g., alkyl, alkenyl) with a carbon number ranging from 2 to 18 (C2-C18). If substituted, the C2-C18 hydrocarbon group may be substituted with halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyl, ether, ketone, ester, epoxy, and / or aryl (e.g., phenyl).

[0086] The R1 component may include an acid labile group (ALG) component, a dissolution inhibitor, and / or another type of component that connects the crosslinking group component 310 to the polymer backbone 308. In some embodiments, the R1 component includes a tert-butyloxycarbonyl group (tBOC). In some embodiments, the R1 component includes a methylcyclopentyl group (MCP) bonded to the carboxyl group of the polymer backbone 308. In some embodiments, the R1 component includes an ethylcyclopentyl group bonded to the carboxyl group of the polymer backbone 308. In some embodiments, R1 is cyclic or non-cyclic, saturated or unsaturated, substituted or unsubstituted, and / or branched or unbranched. In some embodiments, R1 includes a hydrocarbon group (e.g., alkyl, alkenyl) with a carbon number ranging from 2 to 18 (C2-C18). If substituted, the C2-C18 hydrocarbon group may be substituted, inter alia, by halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyl, ether, ketone, ester, epoxy and / or aromatic (e.g., phenyl) groups.

[0087] The cross-linking group component 310 may include a cross-linkable functional group, such as an olefin, an alkyne, a triazene or other suitable functional group. In some implementations, the cross-linking group component 310 is cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and / or branched or unbranched. In some implementations, the cross-linking group component 310 includes a hydrocarbon group (e.g., alkyl, alkenyl) with a carbon number ranging from 2 to 18 (C2-C18). If substituted, the C2-C18 hydrocarbon group may be particularly substituted by halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyl, ether, ketone, ester, epoxy and / or aryl (e.g., phenyl).

[0088] The cross-linking group component 310 may be about 10% to about 99% of the atomic weight of the polymer material 306. In some implementations, an additive is included in the photoresist bottom layer 304 to trigger a cross-linking reaction of the cross-linking group component 310. The additive may be about 0.1% to about 30% of the atomic weight of the cross-linking group component 310 included in the polymer material 306.

[0089] The acid generator component 312 may include a photoacid generator (PAG), a thermal acid generator (TAG), and / or another type of acid generator component that generates an acid based on absorption of radiation and / or heat. The acid generator component 312 may include a combination of one or more cations and one or more anions. The acid generator component 312 may be selected so that the acid generator component 312 diffuses in the photoresist bottom layer 304 through a concentration gradient after a processing operation. The acid generator component 312 may be about 0.1% to about 30% of the atomic weight of the polymer material 306.

[0090] like Figure 3C As shown, a treatment operation 314 is performed on the photoresist bottom layer 304. The treatment operation 314 can be performed to remove solvent from the photoresist bottom layer 304 and / or promote uniform distribution of polar groups in the polymer material 306 on the photoresist bottom layer 304. In some implementations, the treatment operation 314 causes the acid generator component 312 to generate an acid. The treatment operation 314 can include a thermal treatment operation (e.g., a treatment operation in which the photoresist bottom layer 304 is cured with applied heat), an ultraviolet (UV) treatment operation (e.g., a treatment operation in which the photoresist bottom layer 304 is cured with UV radiation), an electron beam (e-beam) treatment operation (e.g., a treatment operation in which the photoresist bottom layer 304 is cured with e-beam radiation), and / or another type of treatment operation.

[0091] For thermal treatment operations, treatment operation 314 may be performed at a temperature ranging from about 100 degrees Celsius to about 400 degrees Celsius to achieve sufficient crosslinking in the photoresist bottom layer 304 without damaging the photoresist bottom layer 304. However, other values ​​within this range are also within the scope of the present disclosure.

[0092] like Figure 3D As shown, after the processing operation 314, the photoresist bottom layer 304 can have a highly uniform polar group distribution on the top surface of the photoresist bottom layer 304. The uniformity of the polar group distribution on the top surface of the photoresist bottom layer after the processing operation is greater than the uniformity of the polar group distribution on the surface of the photoresist layer before the processing operation. The uniformity of the polar group distribution on the top surface of the photoresist bottom layer 304 meets the uniformity threshold. The threshold may be included in the range of about 35% uniformity to about 100% uniformity, so that the uniformity of the polar group distribution on the top surface of the photoresist bottom layer 304 promotes the uniform distribution of the PDB component in the photoresist layer to be formed on the photoresist bottom layer 304. In some implementations, the uniformity of the polar group distribution on the top surface of the photoresist bottom layer 304 is greater than 45%. However, other values ​​of the polar group distribution uniformity on the top surface of the photoresist bottom layer 304 are also within the scope of the present disclosure.

[0093] The uniformity of the distribution of polar groups on the top surface of the photoresist bottom layer 304 can be defined based on the distribution of monomers in the polymer material 306 on the top surface of the photoresist bottom layer 304. For example, the polymer material 306 may include monomers 316 and 318, which may be oxygen (O) monomers and hydrogen (H) monomers (forming hydroxyl (OH) polar groups), respectively. The distribution of comonomers (e.g., monomers 316 and 318) on the top surface of the photoresist bottom layer 304 may meet a uniformity threshold. The uniformity of the distribution of comonomers (e.g., monomers 316 and 318) can be determined as a number-average sequence length (NASL), which is the average number of monomers 316 and 318 across all blocks of a particular monomer in the polymer material 306. The NASL can be determined based on the subunits in the polymer material 306, such as dimer units (1a) and (1b) and trimer units (2a) and (2b) described below:

[0094] (1a)

[0095] (1b)

[0096] (2a)

[0097] (2b)

[0098] Various combinations of monomers 316 and 318 are used to determine the uniformity of distribution. AA It can correspond to the number of occurrences of two adjacent monomers 316, n AB+BA The number of occurrences of a group of monomers 316 and 318 adjacent to a group of monomers 318 and 316, n BB The number of occurrences of two adjacent monomers 318, n AAA The number of occurrences of three adjacent monomers 316, n BAB The number of occurrences of adjacent monomers 318, 316, and 318, n ABA The number of occurrences of adjacent monomers 316, 318, and 316, n AAB+BAA may correspond to the number of occurrences of a group of monomers 316, 316, and 318 adjacent to a group of monomers 318, 316, and 316, and n BBA+ABB The number of occurrences of a group of monomers 318 , 318 , and 316 adjacent to a group of monomers 316 , 318 , and 318 may correspond to that of a group of monomers 318 , 318 , and 316 .

[0099] like Figure 3D As further shown, in some implementations, the high distribution uniformity of monomers 316 and 318 on the top surface of the photoresist bottom layer 304 is defined as the monomers 316 and 318 being arranged in an alternating manner. For example, two adjacent monomers (regardless of whether the adjacent monomers are monomers 316 or monomers 318) may be referred to as unit N. Unit AB may correspond to unit N specifically including monomer 316 and adjacent monomer 318. In some implementations, the ratio of the amount of unit AB to the amount of unit N on the top surface of the photoresist bottom layer 304 (e.g., the amount of unit AB / the amount of unit N) may correspond to the distribution uniformity of the polar group on the top surface of the photoresist bottom layer 304.

[0100] like Figure 3EAs shown, photoresist layer 320 is formed over and / or on photoresist bottom layer 304. Deposition tool 102 may be used to deposit photoresist layer 320 using various PVD techniques, CVD techniques, and / or ALD techniques, such as spin coating, sputtering, PECVD, HDP-CVD, SACVD, and / or PEALD, among others. The photoresist material can be mixed with a solvent, such as propylene glycol methyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 1-ethoxy-2-propanol (PGEE), γ-butyrolactone (GBL), cyclohexanone (CHN), ethyl lactate (EL), methanol, ethanol, propanol, n-butanol, acetone, dimethylformamide (DMF), isopropyl alcohol (IPA), tetrahydrofuran (THF), methyl isobutyl carbinol (MIBC), n-butyl acetate (nBA), 2-heptanone (MAK), and / or another photoresist solvent to facilitate distributing the photoresist material on the semiconductor substrate 210 in a spin coating operation to form a photoresist layer 320.

[0101] like Figure 3E As further shown, the high uniformity of the polar groups (e.g., monomers 316 and 318) on the surface of the photoresist bottom layer 304 promotes uniform distribution of the PDB component 322 in the photoresist layer 320 and inhibits aggregation of the PDB component 322 at the bottom of the photoresist layer 320. If the polar groups are not uniformly distributed on the surface of the photoresist bottom layer 304, regions with a high concentration of the PDB component 322 may otherwise appear in the photoresist layer 320. These regions with a high concentration of the PDB component 322 may quench the generation of photoacid in the photoresist layer 320 too quickly, resulting in a portion of the exposed photoresist layer 320 not being developed, which will cause residual material (e.g., photoresist scum) to remain above the semiconductor substrate 210. Thus, forming the photoresist bottom layer 304 allows the polymer material 306 to have a highly uniform distribution of polar groups on the surface of the photoresist bottom layer 304, thereby facilitating complete development of the pattern in the photoresist layer 320, which reduces the amount of residual material remaining above the semiconductor substrate 210 and reduces the likelihood of defects being formed in the layer 302 and / or in a structure formed in the semiconductor substrate 210 using the pattern.

[0102] like Figure 3FAs shown, a pre-exposure bake operation 324 may be performed on the photoresist layer 320. The pre-exposure bake (or soft bake) operation 324 may include a baking operation performed before exposing the photoresist layer 320 on the semiconductor substrate 210 to the radiation 206 using the exposure tool 104. The pre-exposure bake operation 324 may be performed to evaporate a solvent mixed with the photoresist material. The pre-exposure bake operation 324 may promote the curing of the photoresist material to the photoresist layer 320.

[0103] The duration of pre-exposure baking operation 324 execution can be in the range of about 30 seconds to about 600 seconds, to ensure that photoresist layer 320 is fully baked (and solvent is completely removed), without excessively reducing the throughput of photoresist pattern formation. However, other values ​​of duration are also within the scope of the present disclosure. In some implementations, pre-exposure baking operation 324 can be performed at a temperature within the range of about 65 degrees Celsius to about 200 degrees Celsius, to ensure that solvent is removed from the photoresist material, while reducing and / or minimizing the crosslinking of metal clusters in photoresist layer 320 (this may cause the resolution reduction between the exposed portion and the unexposed portion of photoresist layer 320). However, other temperature values ​​are also within the scope of the present disclosure.

[0104] As mentioned above, FIG. 3A to FIG. 3F Other examples can be found in the FIG. 3A to FIG. 3F Different than described.

[0105] FIG. 4A to FIG. 4C is a diagram of an exemplary implementation 400 of exposing a multilayer photoresist as described herein to radiation 206 to form a pattern in the multilayer photoresist. FIG. 4A to FIG. 4C One or more of the operations described may be performed using the exposure tool 104 and / or another semiconductor processing tool. FIG. 4A to FIG. 4C One or more of the operations described may be combined with FIG. 3A to FIG. 3F One or more of the operations described are then performed.

[0106] like Figure 4A As shown, semiconductor substrate 210 may be positioned on wafer stage 236 of exposure tool 104 for an exposure operation. In the exposure operation, radiation 206 (eg, EUV radiation) is directed onto photoresist layer 320 on semiconductor substrate 210.

[0107] like Figure 4BAs shown, exposure of photoresist layer 320 to radiation 206 results in formation of pattern 402 in photoresist layer 320 that includes portions of photoresist layer 320 exposed to radiation 206. Unexposed portions 404 of photoresist layer 320 remain on semiconductor substrate 210 after the exposure operation.

[0108] like Figure 4C As shown, in the exposed portion of the pattern 402 in the photoresist layer 320, photons 406 of the radiation 206 are absorbed in the photoresist layer 320. The absorbed photons 406 react with the material of the photoresist layer 320, resulting in the formation of secondary electrons 408 (e.g., hot electrons) in the photoresist layer 320. The secondary electrons 408 cause a reaction 410 with the acid generator component 312 that diffuses into the photoresist layer 320.

[0109] As mentioned above, FIG. 4A to FIG. 4C Other examples can be found in the FIG. 4A to FIG. 4C Different than described.

[0110] FIG. 5A to FIG. 5C is a diagram of an exemplary implementation 500 for developing a pattern 402 formed in a photoresist layer 320 of a multi-layer photoresist described herein. FIG. 5A to FIG. 5C One or more of the operations described may be performed using the developer tool 106 and / or another semiconductor processing tool. FIG. 5A to FIG. 5C One or more of the operations described may be combined with FIG. 3A to FIG. 3F and / or FIG. 4A to FIG. 4C One or more of the operations described are then performed.

[0111] like Figure 5A As shown, after exposing the photoresist layer 320 to the radiation 206, one or more post-exposure bake operations 502 may be performed on the photoresist layer 320. The post-exposure bake operation 502 may be performed to promote cross-linking of the photoresist material in the exposed portions of the photoresist layer 320, such as Figure 5A In some implementations, multiple post-exposure bake operations 502 may be performed, such that a first post-exposure bake operation 502 is performed and a second post-exposure bake operation 502 is performed after the first post-exposure bake operation 502. The temperature of the second post-exposure bake operation 502 may be greater relative to the temperature of the first post-exposure operation 502. In this way, performing multiple post-exposure bake operations 502 enables precise control of the temperature ramp of the post-exposure bake of the photoresist layer 320.

[0112] like Figure 5BAs shown, a post-exposure bake operation 502 initiates the formation of photoacid in the photoresist layer 320. Photoacid 504 generated by the acid generator component 312, which causes acid diffusion 506 into the photoresist layer 320, reacts with the hot electrons at 410 to generate photoacid 504, which causes the formation of deprotected spheres in the photoresist layer 320.

[0113] The PDB component 322 in the photoresist layer 320 can neutralize the photoacid 504 so that the formation of the photoacid 504 is controlled in a manner that allows the formation of the pattern 402 with a low LWR. As described above, the high uniformity of the polar groups (e.g., monomers 316 and 318) on the surface of the photoresist bottom layer 304 promotes the uniform distribution of the PDB component 322 in the photoresist layer 320 and inhibits the aggregation of the PDB component 322 at the bottom of the photoresist layer 320. If the polar groups are not uniformly distributed on the surface of the photoresist bottom layer 304, regions with a high concentration of the PDB component 322 may otherwise appear in the photoresist layer 320. These regions with a high concentration of the PDB component 322 may quench the generation of the photoacid 504 too quickly, thereby producing an undeveloped portion of the exposed photoresist layer 320, which will cause residual material (e.g., photoresist scum) to remain above the semiconductor substrate 210. Therefore, forming the photoresist bottom layer 304 so that the polymer material 306 has a high distribution uniformity of polar groups on the surface of the photoresist bottom layer 304 promotes complete development of the pattern 402 in the photoresist layer 320, which reduces the amount of residual material remaining above the semiconductor substrate 210 and reduces the possibility of defects being formed in the layer 302 and / or in the structure formed in the semiconductor substrate 210 using the pattern 402.

[0114] In some implementations, the post-exposure bake operation 502 is performed for a duration in a range of about 60 seconds to about 600 seconds to ensure sufficient cross-link density in the exposed portion of the pattern 402 formed in the photoresist layer 320 without causing excessive cross-linking (which may result in an increased amount of photoresist residue remaining on the semiconductor substrate 210 after a development operation). However, other values ​​for the duration of each post-exposure bake operation are also within the scope of the present disclosure.

[0115] In some implementations, the post-exposure bake operation 502 can be performed at a temperature in a range of about 80 degrees Celsius to about 350 degrees Celsius to ensure sufficient generation of the photoacid 504 in the photoresist layer 320 without causing excessive cross-linking in the photoresist layer 320. However, other values ​​of the temperature of the post-exposure bake operation 502 are also within the scope of the present disclosure.

[0116] like Figure 5CAs shown, after the exposure operation and one or more post-exposure bake operations 502, the pattern 402 is developed in the photoresist layer 320. The developer tool 106 can be used to perform a development operation to develop the pattern 402. The duration of the development operation can be in the range of about 30 seconds to about 60 seconds. However, other values ​​of the duration are also within the scope of the present disclosure.

[0117] The developer tool 106 can be used with various types of developers, such as 2-heptanone and / or another type of developer. After performing the development operation, the pattern 402 can be used for subsequent semiconductor processing operations, which can include etching the layer 302 and / or the semiconductor substrate 210, implanting ions into the layer 302 and / or the semiconductor substrate 210, patterning the layer 302 as a hard mask, and / or another type of semiconductor processing operation.

[0118] As mentioned above, FIG. 5A to FIG. 5C Other examples can be found in the FIG. 5A to FIG. 5C Different than described.

[0119] Fig. 6A and Figure 6B 310 is a diagram of examples of materials that can be used for the R1 component and the crosslinking group component 310 described herein. Fig. 6A and Figure 6B As shown, the cross-linking group component 310 included in the polymer material 306 of the photoresist bottom layer 304 may include Fig. 6A and Figure 6B 602 to 626 shown in . The molecules 602 to 626 of the cross-linking group component 310 may include cross-linkable functional groups, such as olefins, alkynes, triazenes, hydrocarbons, halogens, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyls, ethers, ketones, esters, epoxy groups, and / or aryls (e.g., phenyls), etc. In some implementations, multiple molecules of the cross-linking group component 310 may be bonded to a single R1 component, such as shown for molecules 602, 604, 606, and 608. In these implementations, m (e.g., the amount of molecules 602, 604, 606, and / or 608 bonded to the same R1 component) may be included in the range of 1 to 12. However, other values ​​within this range are also within the scope of the present disclosure.

[0120] As mentioned above, Fig. 6A and Figure 6B Other examples can be found in the Fig. 6A and Figure 6B Different than described.

[0121] 7A to 7C is a diagram of examples of materials that may be used for the acid generator component 312 described herein. Fig. 7A and Figure 7B Examples of PAG molecules 702 to 730 are shown, and Figure 7C Examples of TAG molecules 732 to 746 are shown.

[0122] The PAG acid generator component 312 may include one or more cations (corresponding to PAG molecules 702 and 704) and one or more anions (corresponding to PAG molecules 706 to 730). The R component of the PAG molecules 712 to 716 may be cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and / or branched or unbranched. The R component may include a hydrocarbon group having a carbon number ranging from 1 carbon atom to 9 carbon atoms (e.g., a C1-C9 hydrocarbon group), such as an alkyl group and / or an alkenyl group, etc. However, other values ​​of this range are also within the scope of the present disclosure. If substituted, the C1-C9 hydrocarbon group may be substituted, inter alia, by halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyl, ether, ketone, ester, epoxy and / or aryl (e.g., phenyl).

[0123] The TAG acid generator component 312 may include one or more TAG molecules of TAG molecules 732 to 746. The R component of the TAG molecule 746 may be cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and / or branched or unbranched. The R component may include a hydrocarbon group (e.g., C1-C9 hydrocarbon group) with a carbon number ranging from 1 carbon atom to 9 carbon atoms, such as an alkyl group and / or an alkenyl group, etc. However, other values ​​of this range are also within the scope of the present disclosure. If substituted, the C1-C9 hydrocarbon group may be particularly substituted by halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxyl, ether, ketone, ester, epoxy and / or aryl (e.g., phenyl). In some implementations, n in the TAG molecules 746 may be included in the range of 1 to 4. However, other values ​​within this range are also within the scope of the present disclosure.

[0124] As mentioned above, 7A to 7C Other examples can be found in the 7A to 7C Different than described.

[0125] FIG. 8A to FIG. 8C FIG. 8 is a diagram of an exemplary implementation 800 of a multilayer photoresist as described herein. FIG. 8A to FIG. 8CIn the embodiment, the multilayer photoresist includes a photoresist bottom layer 304 and a photoresist layer 320, similar to the combination of FIG. 3A to FIG. 3F The multi-layer photoresist in the exemplary implementation 300 is described. FIG. 8A to FIG. 8C As further shown in FIG. 2 , multiple layers of photoresist are formed over semiconductor substrate 210 and may be formed on layer 304 on semiconductor substrate 210 .

[0126] like Fig. 8A As shown, the photoresist bottom layer 304 includes a polymer material 306. The polymer material 306 includes a polymer backbone 308 and an acid generator component side chain 802 that links the acid generator component 312 to the polymer backbone 308. The acid generator component side chain 802 includes a branched or linear, cyclic or non-cyclic, saturated or unsaturated hydrocarbon group. The hydrocarbon group may include 5 to 40 carbon atoms (e.g., C5-C40 hydrocarbon group) bonded by one or more types of bonds (e.g., -C=C- and / or -C≡C-). However, other values ​​of this range are also within the scope of the present disclosure. If substituted, the acid generator component side chain 802 may contain halogen, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=O)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, -SO2-, carboxylic acid, ether, ketone, ester, epoxy and / or benzene units, etc.

[0127] like Figure 8B and Figure 8C As shown, the acid generator component side chain 802 couples the acid generator component 312 to the polymer backbone 308 of the polymer material 306 to control the diffusion of the acid generator component 312 into the photoresist layer 320. This prevents (or inhibits) the acid generator component 312 from uncontrollably diffusing into the photoresist layer 320 and promotes a uniform concentration of the acid generator component 312 at the bottom of the photoresist layer 320. When performing FIG. 4A to FIG. 4C The exposure operation described in the above embodiment and developing the pattern 402 in the photoresist layer 320 (such as in combination with FIG. 5A to FIG. 5CWhen the pattern 402 is developed, the acid generator component 312 remaining at the bottom of the photoresist layer 320 promotes the formation of photoacid 504 at the bottom of the photoresist layer 320. When the pattern 402 is developed, the photoacid 504 generated at the bottom of the photoresist layer 320 enables the bottommost portion of the photoresist layer 320 to be developed and removed. This reduces the likelihood that residual photoresist material will remain in the photoresist layer 320, which can reduce LCDU and / or can reduce LWR in features formed in the layer 302 and / or in the semiconductor substrate 210 using the multilayer photoresist. Reduced LWR and / or reduced LCDU can enable features to be formed to smaller sizes and / or increased uniformity, thereby increasing the yield of semiconductor structures formed on the semiconductor substrate 210.

[0128] As mentioned above, FIG. 8A to FIG. 8C Other examples can be found in the FIG. 8A to FIG. 8C Different than described.

[0129] Fig. 9 is a diagram of an exemplary implementation 900 of the photoresist bottom layer 304 described herein. Fig. 9 As shown, in the exemplary implementation 900, the photoresist bottom layer 304 includes a plurality of polymer materials, including a polymer material 306a and a polymer material 306b.

[0130] The polymer material 306a and the polymer material 306b may include different components as described herein. For example, the polymer material 306a may include a polymer backbone 308a and a crosslinking group component 310 bonded to the polymer backbone 308a via an R1 component. The polymer material 306a may be included in the photoresist bottom layer 304 to promote uniform distribution of polar groups in the photoresist bottom layer 304.

[0131] The polymer material 306b may include a polymer backbone 308b, a plurality of acid generator component side chains 802, and an acid generator component 312 bonded to the polymer backbone 308b through the plurality of acid generator component side chains 802. The polymer material 306b may be included in the photoresist bottom layer 304 to control diffusion of the acid generator component 312 into the photoresist layer 320 on the photoresist bottom layer 304.

[0132] As mentioned above, Fig. 9 Other examples can be found in the Fig. 9 Different than described.

[0133] Fig.10 is a diagram of an exemplary implementation 1000 of the photoresist bottom layer 304 described herein. Fig.10As shown, in exemplary implementation 1000 , photoresist bottom layer 304 includes copolymer material 1002 .

[0134] The copolymer material 1002 includes a polymer backbone 308. The copolymer material 1002 may include a cross-linking group component 310 bonded to the polymer backbone 308 via an R1 component to promote uniform distribution of polar groups in the photoresist bottom layer 304. The copolymer material 1002 may also include a plurality of acid generator component side chains 802, and an acid generator component 312 bonded to the polymer backbone 308 via the plurality of acid generator component side chains 802 to control diffusion of the acid generator component 312 into the photoresist layer 320 on the photoresist bottom layer 304.

[0135] As mentioned above, Fig.10 Other examples can be found in the Fig.10 Different than described.

[0136] Fig.11 is a diagram of an exemplary implementation 1100 of the photoresist bottom layer 304 described herein. Fig.11 As shown, in the exemplary implementation 1100 , the photoresist bottom layer 304 includes a plurality of polymer materials, including polymer material 306 a , polymer material 306 b , and copolymer material 1002 .

[0137] The polymer material 306a may include a polymer backbone 308a and a cross-linking group component 310a bonded to the polymer backbone 308a through an R1 component. The polymer material 306a may be included in the photoresist bottom layer 304 to promote uniform distribution of polar groups in the photoresist bottom layer 304.

[0138] The polymer material 306b may include a polymer backbone 308b, a plurality of acid generator component side chains 802a, and an acid generator component 312a bonded to the polymer backbone 308b via the plurality of acid generator component side chains 802a. The polymer material 306b may be included in the photoresist bottom layer 304 to control diffusion of the acid generator component 312a into the photoresist layer 320 on the photoresist bottom layer 304.

[0139] The copolymer material 1002 includes a polymer backbone 308c. The copolymer material 1002 may include a cross-linking group component 310b bonded to the polymer backbone 308c via an R1 component to promote uniform distribution of polar groups in the photoresist bottom layer 304. The copolymer material 1002 may also include a plurality of acid generator component side chains 802b, and an acid generator component 312b bonded to the polymer backbone 308c via the plurality of acid generator component side chains 802b to control diffusion of the acid generator component 312b into the photoresist layer 320 on the photoresist bottom layer 304.

[0140] As mentioned above, Fig.11 Other examples can be found in the Fig.11 Different than described.

[0141] Fig.12 1200 is a diagram of exemplary components of the apparatus 1200 described herein. In some implementations, one or more of the semiconductor processing tools 102 to 108 and / or the wafer / die transport tool 110 may include one or more apparatuses 1200 and / or one or more components of the apparatus 1200. Fig.12 As shown, the device 1200 may include a bus 1210 , a processor 1220 , a memory 1230 , an input component 1240 , an output component 1250 , and / or a communication component 1260 .

[0142] The bus 1210 may include one or more components that enable wired and / or wireless communication between components of the device 1200. The bus 1210 may include one or more components that enable wired and / or wireless communication between components of the device 1200. Fig.12 Two or more components of a computer program product may be coupled together, for example, via an operational coupling, a communication coupling, an electronic coupling, and / or an electrical coupling. For example, bus 1210 may include an electrical connection (e.g., a wire, a trace, and / or a lead) and / or a wireless bus. Processor 1220 may include a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field programmable gate array, an application specific integrated circuit, and / or another type of processing component. Processor 1220 may be implemented in hardware, firmware, or a combination of hardware and software. In some implementations, processor 1220 may include one or more processors that can be programmed to perform one or more operations or processes described elsewhere herein.

[0143] The memory 1230 may include volatile and / or non-volatile memory. For example, the memory 1230 may include random access memory (RAM), read-only memory (ROM), a hard drive, and / or another type of memory (e.g., flash memory, magnetic memory, and / or optical memory). The memory 1230 may include internal memory (e.g., RAM, ROM, or hard drive) and / or removable memory (e.g., removable via a universal serial bus connection). The memory 1230 may be a non-transitory computer-readable medium. The memory 1230 may store information, one or more instructions, and / or software (e.g., one or more software applications) related to the operation of the device 1200. In some implementations, the memory 1230 may include, for example, one or more memories coupled (e.g., communicatively coupled) to one or more processors (e.g., processor 1220) via bus 1210. The communicative coupling between the processor 1220 and the memory 1230 may enable the processor 1220 to read and / or process information stored in the memory 1230 and / or store information in the memory 1230.

[0144] Input components 1240 can enable device 1200 to receive input, such as user input and / or sensed input. For example, input components 1240 may include touch screens, keyboards, keypads, mice, buttons, microphones, switches, sensors, GPS sensors, GNSS sensors, accelerometers, gyroscopes, and / or actuators. Output components 1250 can enable device 1200 to provide output, such as via displays, speakers, and / or light emitting diodes. Communication components 1260 can enable device 1200 to communicate with other devices via wired connections and / or wireless connections. For example, communication components 1260 may include receivers, transmitters, transceivers, modems, network interface cards, and / or antennas.

[0145] The device 1200 may perform one or more operations or processes described herein. For example, a non-transitory computer-readable medium (e.g., memory 1230) may store a set of instructions (e.g., one or more instructions or codes) for execution by the processor 1220. The processor 1220 may execute a set of instructions to perform one or more operations or processes described herein. In some implementations, execution of the set of instructions by one or more processors 1220 causes one or more processors 1220 and / or the device 1200 to perform one or more operations or processes described herein. In some implementations, hardwired circuitry may be used instead of instructions or in combination with instructions to perform one or more operations or processes described herein. Additionally or alternatively, the processor 1220 may be configured to perform one or more operations or processes described herein. Therefore, the implementations described herein are not limited to any particular combination of hardware circuitry and software.

[0146] Fig.12 The number and arrangement of components shown are provided as examples. Apparatus 1200 may include Fig.12 Additional components, fewer components, different components, or differently arranged components than those shown. Additionally or alternatively, one or more components of the device 1200 may perform one or more functions described as being performed by another set of components of the device 1200.

[0147] Fig.13 1 is a flow chart of an exemplary process 1300 associated with forming a multilayer photoresist on a semiconductor substrate as described herein. In some implementations, one or more semiconductor processing tools (e.g., one or more of semiconductor processing tools 102 to 108) are used to perform Fig.13 Additionally or alternatively, Fig.13 One or more process blocks of may be performed using one or more components of the apparatus 1200 , such as the processor 1220 , the memory 1230 , the input component 1240 , the output component 1250 , and / or the communication component 1260 .

[0148] like Fig.13 As shown, process 1300 may include forming a photoresist bottom layer over a substrate (block 1310). For example, one or more of semiconductor processing tools 102 to 108 are used to form a photoresist bottom layer 304 over a semiconductor substrate 210, as described herein. In some implementations, the photoresist bottom layer 304 includes a polymer material 306 and an acid generator component 312.

[0149] like Fig.13 As further shown, process 1300 may include performing a treatment operation on the photoresist bottom layer (block 1320). For example, one or more of semiconductor processing tools 102 to 108 may be used to perform treatment operation 314 on photoresist bottom layer 304, as described herein. In some implementations, a uniformity of polar group distribution on a top surface of the photoresist bottom layer after the treatment operation is greater than a uniformity of polar group distribution on a surface of the photoresist layer before the treatment operation. In some implementations, after the thermal treatment operation, the uniformity of polar group distribution on the top surface of the photoresist bottom layer satisfies a uniformity threshold. In some implementations, the treatment operation includes at least one of a thermal treatment operation, a UV treatment operation, an e-beam treatment operation, and / or another type of treatment operation.

[0150] like Fig.13As further shown, process 1300 may include forming a photoresist layer over the photoresist bottom layer after the processing operation (block 1330). For example, one or more of semiconductor processing tools 102-108 may be used to form photoresist layer 320 over photoresist bottom layer 304 after processing operation 314, as described herein.

[0151] like Fig.13 As further shown, the process 1300 may include exposing the photoresist layer to radiation to form a pattern in the photoresist layer (block 1340). For example, one or more of the semiconductor processing tools 102 to 108 may be used to expose the photoresist layer to radiation 206 to form a pattern 402 in the photoresist layer 320, as described herein. In some implementations, the acid generator component 312 in the photoresist bottom layer 304 generates an acid (e.g., photoacid 504) based on at least one of the processing operation or the radiation 206, which causes the pattern 402 to be formed in the photoresist layer 320.

[0152] like Fig.13 As further shown, process 1300 may include developing the pattern in the photoresist layer (block 1350). For example, one or more of semiconductor processing tools 102-108 may be used to develop pattern 402 in photoresist layer 320, as described herein.

[0153] Process 1300 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in combination with one or more other processes described elsewhere herein.

[0154] In a first implementation, the photoresist layer 320 includes a PDB component 322 , and the polar group distribution uniformity satisfying the uniformity threshold promotes uniform distribution of the PDB component 322 in the photoresist layer 320 .

[0155] In a second implementation alone or in combination with the first implementation, the photoresist layer 320 includes a PDB component 322 , and the polar group distribution uniformity satisfying the uniformity threshold suppresses aggregation of the PDB component 322 at the bottom of the photoresist layer 320 .

[0156] In a third implementation, alone or in combination with one or more of the first and second implementations, the photoresist bottom layer 304 includes at least one of an intermediate layer, a bottom layer, or a BARC layer.

[0157] In a fourth implementation, alone or in combination with one or more of the first to third implementations, performing the processing operation 314 includes performing the processing operation 314 at a temperature included in the range of greater than about 100 degrees Celsius to about 400 degrees Celsius.

[0158] In a fifth implementation, alone or in combination with one or more of the first to fourth implementations, the uniformity threshold is included in the range of about 35% to about 100%.

[0159] In a sixth implementation, alone or in combination with one or more of the first to fifth implementations, forming the photoresist bottom layer 304 includes forming the photoresist bottom layer 304 to a thickness (dimension D1) included in the range of about 5 angstroms to about 500 angstroms. In a seventh implementation, alone or in combination with one or more of the first to fifth implementations, the photoresist bottom layer 304 includes a polymer backbone (e.g., polymer chain 308, polymer chain 308a, polymer chain 308b), a plurality of acid generator component side chains 802 coupled to the polymer backbone, and an acid generator component 312 coupled to the plurality of acid generator component side chains 802;

[0160] In an eighth implementation, alone or in combination with one or more of the first to seventh implementations, the polymer backbone is a first polymer backbone in a first polymer material 306a contained in a photoresist bottom layer 304, and wherein a second polymer material 306b contained in the photoresist bottom layer 304 comprises a second polymer backbone 308b, a cross-linking group component 310, and a plurality of polar groups (e.g., monomer 316, monomer 318).

[0161] In a ninth implementation, alone or in combination with one or more of the first to eighth implementations, the photoresist bottom layer 304 includes a copolymer material 1002, which includes a polymer backbone, multiple acid generator component side chains 802, an acid generator component 312, a cross-linking group component 310, and multiple polar groups (e.g., monomer 316, monomer 318).

[0162] In a tenth implementation alone or in combination with one or more of the first to ninth implementations, the polymer backbone is a first polymer backbone 308c included in a photoresist underlying layer 304, the plurality of acid generator component side chains 802 are a first plurality of acid generator component side chains 802b included in the photoresist underlying layer 304, the acid generator component 312 is a first acid generator component 312b included in the photoresist underlying layer 304, and the polymer material 306b included in the photoresist underlying layer 304 includes a second polymer backbone 308b, a second plurality of acid generator component side chains 802a coupled to the second polymer backbone 308b, and a second acid generator component 312a coupled to the second plurality of acid generator component side chains 802a.

[0163] In an eleventh implementation alone or in combination with one or more of the first to tenth implementations, the polymer backbone is a first polymer backbone 308c contained in the photoresist bottom layer 304, the cross-linking group component 310 is a first cross-linking group component 310b contained in the photoresist bottom layer 304, the plurality of polar groups are a first plurality of polar groups contained in the photoresist bottom layer, and the polymer material 306a contained in the photoresist bottom layer 304 comprises a second polymer backbone 308a, a second cross-linking group component 310a, and a second plurality of polar groups (e.g., monomer 316, monomer 318).

[0164] In a twelfth implementation, which is alone or in combination with one or more of the first to eleventh implementations, the polymer backbone is the first polymer backbone 308c included in the photoresist bottom layer 304, the plurality of acid generator component side chains 802 are the first plurality of acid generator component side chains 802b included in the photoresist bottom layer 304, the acid generator component 312 is the first acid generator component 312b included in the photoresist bottom layer 304, the crosslinking group component 310 is the first crosslinking group component 310b included in the photoresist bottom layer 304, and the plurality of polar groups are photoresist components. The first plurality of polar groups included in the photoresist bottom layer 304, the first polymer material 306a included in the photoresist bottom layer 304 includes a second polymer backbone 308a, a second cross-linking group component 310a, and a second plurality of polar groups (for example, monomer 316, monomer 318), and the second polymer material 306b included in the photoresist bottom layer 304 includes a third polymer backbone 308b, a second plurality of acid generator component side chains 802a coupled to the second polymer backbone 306b, and a second acid generator component 312a coupled to the second plurality of acid generator component side chains 802a.

[0165] although Fig.13An exemplary block diagram of process 1300 is shown, but in some implementations, process 1300 includes Fig.13 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in the process 1300. Additionally or alternatively, two or more blocks of the process 1300 may be executed in parallel.

[0166] Fig.14 14 is a flow chart of an exemplary process 1400 associated with forming a multilayer photoresist on a semiconductor substrate as described herein. In some implementations, one or more semiconductor processing tools (e.g., one or more of semiconductor processing tools 102 to 108) are used to perform Fig.14 Additionally or alternatively, Fig.14 One or more process blocks of may be performed using one or more components of the apparatus 1200 , such as the processor 1220 , the memory 1230 , the input component 1240 , the output component 1250 , and / or the communication component 1260 .

[0167] like Fig.14 As shown, process 1400 may include forming a photoresist bottom layer over a substrate (block 1410). For example, one or more of semiconductor processing tools 102 to 108 may be used to form photoresist bottom layer 304 over semiconductor substrate 210, as described herein. In some implementations, photoresist bottom layer 304 includes a polymer backbone 308, a plurality of acid generator component side chains 802 coupled to the polymer backbone 308, and an acid generator component 312 coupled to the plurality of acid generator component side chains 802.

[0168] like Fig.14 As further shown, process 1400 may include forming a photoresist layer over the photoresist bottom layer (block 1420). For example, one or more of semiconductor processing tools 102-108 may be used to form photoresist layer 320 over photoresist bottom layer 304, as described herein.

[0169] like Fig.14 As further shown, process 1400 may include exposing the photoresist layer to radiation to form a pattern in the photoresist layer (block 1430). For example, one or more of semiconductor processing tools 102 to 108 may be used to expose photoresist layer 320 to radiation 206 to form pattern 402 in the photoresist layer, as described herein. In some implementations, acid generator component 312 in the photoresist bottom layer reacts with the radiation to form an acid (e.g., photoacid 504), which causes pattern 402 to be formed in photoresist layer 320.

[0170] like Fig.14As further shown, process 1400 may include developing the pattern in the photoresist layer (block 1440). For example, one or more of semiconductor processing tools 102-108 may be used to develop pattern 402 in photoresist layer 320, as described herein.

[0171] Process 1400 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in combination with one or more other processes described elsewhere herein.

[0172] In a first implementation, the plurality of acid generator component side chains 802 include a plurality of hydrocarbon bonded structures, halogens, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=Ohydrocarbon)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, or -SO2-.

[0173] In a second implementation, either alone or in combination with the first implementation, one of the plurality of hydrocarbyl bonded structures is included in the range of a hydrocarbyl group of 5 carbon atoms to a hydrocarbyl group of 40 carbon atoms.

[0174] In a third implementation, alone or in combination with one or more of the first and second implementations, the plurality of acid generator component side chains 802 include at least one of carboxylic acid, ether, ketone, ester, epoxy, or benzene units.

[0175] In a fourth implementation, alone or in combination with one or more of the first to third implementations, the plurality of acid generator component side chains 802 include cations and anions.

[0176] In a fifth implementation, alone or in combination with one or more of the first to fourth implementations, a length of one of the plurality of acid generator component side chains 802 is included in the range of about 1 nanometer to about 10 nanometers.

[0177] In a sixth implementation alone or in combination with one or more of the first to fifth implementations, the acid generator component 312 diffuses into the photoresist layer 320 , and the plurality of acid generator component side chains 802 retain the acid generator component 312 at the bottom of the photoresist layer 320 .

[0178] although Fig.14 An exemplary block diagram of process 1400 is shown, but in some implementations, process 1400 includes Fig.14 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in the process 1400. Additionally or alternatively, two or more blocks of the process 1400 may be executed in parallel.

[0179] In this way, a multilayer photoresist can be used to manufacture semiconductor devices. The multilayer photoresist is formed of one or more materials that reduce the possibility and / or the amount of residual material remaining in the photoresist layer of the multilayer photoresist after the photoresist layer is exposed to EUV radiation and developed. In some implementations, the photoresist bottom layer of the multilayer photoresist includes a polymer with a highly uniformly distributed polar group monomer. In addition and / or alternatively, the photoresist bottom layer includes a polymer, the polymer including a main chain and a plurality of side chains coupled to the main chain. In particular, the side chain includes an acid generator component, such as PAG and / or TAG. Since the acid generator component is coupled to the main chain of the polymer through the side chain, rather than being diffused into the photoresist layer uncontrollably, the acid generated by the acid generator component when exposed to EUV radiation gathers in a uniform manner below the bottom of the photoresist layer and enables the bottommost portion of the photoresist layer to be developed and removed. This reduces the likelihood that residual photoresist material will remain in the photoresist layer, which can reduce LCDU and / or can reduce LWR in features formed in a semiconductor device using multiple layers of photoresist. Reduced LWR and / or reduced LCDU can enable features to be formed to smaller sizes and / or increased uniformity, thereby increasing the yield of semiconductor structures formed on a semiconductor device.

[0180] As described in more detail above, some implementations described herein provide a method. The method includes forming a photoresist bottom layer above a substrate, wherein the photoresist bottom layer comprises a polymer and an acid generator component. The method includes performing a treatment operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation. The method includes forming a photoresist layer above the photoresist bottom layer after the treatment operation. The method includes exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid, and the acid causes the pattern to be formed in the photoresist layer. The method includes developing the pattern in the photoresist layer.

[0181] As described in more detail above, some implementations described herein provide a method. The method includes forming a photoresist bottom layer above a substrate, wherein the photoresist bottom layer comprises: a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains. The method includes forming a photoresist layer above the photoresist bottom layer. The method includes exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid, which causes the pattern to be formed in the photoresist layer. The method includes developing the pattern in the photoresist layer.

[0182] As described in more detail above, some implementations described herein provide a method. The method includes forming a photoresist bottom layer above a substrate, wherein the photoresist bottom layer comprises: a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains. The method includes performing a treatment operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation. The method includes forming a photoresist layer above the photoresist bottom layer after the treatment operation. The method includes exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid, and the acid causes the pattern to be formed in the photoresist layer. The method includes developing the pattern in the photoresist layer.

[0183] Some exemplary implementations are described below:

[0184] Embodiment 1. A method, comprising:

[0185] forming a photoresist bottom layer over the substrate,

[0186] wherein the photoresist bottom layer comprises a polymer and an acid generator component;

[0187] performing a processing operation on the photoresist bottom layer,

[0188] wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation;

[0189] forming a photoresist layer over the photoresist bottom layer after the processing operation;

[0190] exposing the photoresist layer to radiation to form a pattern in the photoresist layer,

[0191] wherein the acid generator component in the photoresist bottom layer generates an acid based on at least one of the processing operation or the radiation, the acid causing the pattern to be formed in the photoresist layer; and

[0192] The pattern in the photoresist layer is developed.

[0193] Embodiment 2. The method of embodiment 1, wherein after the processing operation, the polar group distribution uniformity on the surface of the photoresist layer satisfies a uniformity threshold; and

[0194] Wherein the uniformity threshold is comprised within the range of about 35% to about 100%.

[0195] Embodiment 3. The method of embodiment 2, wherein the photoresist layer comprises a photodecomposable base (PDB) component; and

[0196] The polar group distribution uniformity, wherein satisfying the uniformity threshold, promotes uniform distribution of the PDB component in the photoresist layer.

[0197] Embodiment 4. The method of embodiment 2, wherein the photoresist layer comprises the photodecomposable base component; and

[0198] The polar group distribution uniformity, wherein satisfying the uniformity threshold, suppresses aggregation of the PDB component at the bottom of the photoresist layer.

[0199] Embodiment 5. The method of embodiment 1, wherein the photoresist bottom layer comprises at least one of:

[0200] Middle layer (ML),

[0201] Bottom layer (BL), or

[0202] Bottom anti-reflective coating (BARC) layer.

[0203] Embodiment 6. The method of embodiment 1, wherein performing the processing operation comprises:

[0204] The thermal treatment operation is performed at a temperature included in a range of greater than about 100 degrees Celsius to about 400 degrees Celsius.

[0205] Embodiment 7. The method of embodiment 1, wherein the processing operation comprises at least one of:

[0206] Heat treatment operations,

[0207] Ultraviolet (UV) treatment operations, or

[0208] Electron beam (e-beam) processing operations.

[0209] Embodiment 8. A method comprising:

[0210] forming a photoresist bottom layer over the substrate,

[0211] The photoresist bottom layer comprises:

[0212] a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains;

[0213] forming a photoresist layer over the photoresist bottom layer;

[0214] exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with the radiation to form an acid that causes the pattern to be formed in the photoresist layer; and

[0215] The pattern in the photoresist layer is developed.

[0216] Embodiment 9. A method according to embodiment 8, wherein the plurality of acid generator component side chains comprise at least one of the following: a plurality of hydrocarbon bonded structures, halogens, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=Ohydrocarbon)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, or -SO2-.

[0217] Embodiment 10. The method according to embodiment 9, wherein one of the plurality of hydrocarbyl bonded structures is contained within the range of a hydrocarbyl group of 5 carbon atoms to a hydrocarbyl group of 40 carbon atoms.

[0218] Embodiment 11. The method of embodiment 8, wherein the plurality of acid generator component side chains comprise at least one of:

[0219] carboxylic acid,

[0220] ether,

[0221] ketone,

[0222] ester,

[0223] Epoxy, or

[0224] Benzene unit.

[0225] Embodiment 12. The method of embodiment 8, wherein the plurality of acid generator component side chains comprise cations and anions.

[0226] Embodiment 13. The method according to embodiment 8, wherein the length of one of the plurality of acid generator component side chains is comprised within a range of about 1 nanometer to about 10 nanometers.

[0227] Embodiment 14. The method of embodiment 8, wherein the acid generator component diffuses into the photoresist layer; and

[0228] The plurality of acid generator component side chains maintain the acid generator component at the bottom of the photoresist layer.

[0229] Embodiment 15. A method comprising:

[0230] forming a photoresist bottom layer over the substrate,

[0231] The photoresist bottom layer comprises:

[0232] a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains;

[0233] performing a processing operation on the photoresist bottom layer,

[0234] wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation;

[0235] forming a photoresist layer over the photoresist bottom layer after the processing operation;

[0236] exposing the photoresist layer to radiation to form a pattern in the photoresist layer,

[0237] wherein the acid generator component in the photoresist bottom layer reacts with radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; and

[0238] The pattern in the photoresist layer is developed.

[0239] Embodiment 16. The method of embodiment 15, wherein the polymer backbone is a first polymer backbone in a first polymer material contained in the photoresist bottom layer; and

[0240] The second polymer material contained in the photoresist bottom layer comprises:

[0241] a second polymer backbone;

[0242] a cross-linking group component; and

[0243] Multiple polar groups.

[0244] Embodiment 17. The method of embodiment 15, wherein the photoresist bottom layer comprises a copolymer material comprising:

[0245] The polymer backbone;

[0246] the plurality of acid generator component side chains;

[0247] The acid generator component;

[0248] a cross-linking group component; and

[0249] Multiple polar groups.

[0250] Embodiment 18. The method of embodiment 17, wherein the polymer backbone is a first polymer backbone contained in the photoresist bottom layer;

[0251] wherein the plurality of acid generator component side chains are the first plurality of acid generator component side chains contained in the photoresist bottom layer;

[0252] wherein the acid generator component is a first acid generator component contained in the photoresist bottom layer; and

[0253] The polymer material contained in the photoresist bottom layer comprises:

[0254] a second polymer backbone;

[0255] a second plurality of acid generator component side chains coupled to the second polymer backbone; and

[0256] A second acid generator component is side-chain coupled to the second plurality of acid generator components.

[0257] Embodiment 19. The method of embodiment 17, wherein the polymer backbone is a first polymer backbone contained in the photoresist bottom layer;

[0258] wherein the cross-linking group component is the first cross-linking group component contained in the photoresist bottom layer;

[0259] wherein the plurality of polar groups are the first plurality of polar groups contained in the photoresist bottom layer; and

[0260] The polymer material contained in the photoresist bottom layer comprises:

[0261] a second polymer backbone;

[0262] a second cross-linking group component; and

[0263] A second plurality of polar groups.

[0264] Embodiment 20. The method of embodiment 17, wherein the polymer backbone is a first polymer backbone contained in the photoresist bottom layer;

[0265] wherein the plurality of acid generator component side chains are the first plurality of acid generator component side chains contained in the photoresist bottom layer;

[0266] wherein the acid generator component is the first acid generator component contained in the photoresist bottom layer;

[0267] wherein the cross-linking group component is the first cross-linking group component contained in the photoresist bottom layer;

[0268] wherein the plurality of polar groups are the first plurality of polar groups contained in the photoresist bottom layer;

[0269] The first polymer material contained in the photoresist bottom layer comprises:

[0270] a second polymer backbone;

[0271] a second cross-linking group component; and

[0272] a second plurality of polar groups; and

[0273] The second polymer material contained in the photoresist bottom layer comprises:

[0274] a third polymer backbone;

[0275] a second plurality of acid generator component side chains coupled to the second polymer backbone; and

[0276] A second acid generator component is side-chain coupled to the second plurality of acid generator components.

[0277] As used herein, "satisfying a threshold" may refer to a value being greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0278] The foregoing summarizes the features of several embodiments so that those skilled in the art can better understand the various aspects of the present disclosure. Those skilled in the art will appreciate that they can easily use the present disclosure as a basis for designing or modifying other methods and structures to implement the same purposes and / or achieve the same advantages as the embodiments described herein. Those skilled in the art will also appreciate that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they can make various changes, substitutions, and modifications without departing from the spirit and scope of the present disclosure.

Claims

1. A method, comprising: forming a photoresist bottom layer over the substrate, wherein the photoresist bottom layer comprises a polymer and an acid generator component; performing a processing operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation; forming a photoresist layer over the photoresist bottom layer after the processing operation; exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer generates an acid based on at least one of the processing operation or the radiation, the acid causing the pattern to be formed in the photoresist layer; as well as The pattern in the photoresist layer is developed.

2. The method of claim 1 , wherein after the processing operation, the polar group distribution uniformity on the surface of the photoresist layer satisfies a uniformity threshold; and Wherein the uniformity threshold is comprised within the range of about 35% to about 100%.

3. The method of claim 2, wherein the photoresist layer comprises a photodecomposable base (PDB) component; and The polar group distribution uniformity, wherein satisfying the uniformity threshold, promotes uniform distribution of the PDB component in the photoresist layer.

4. The method according to claim 2, wherein the photoresist layer comprises the photodecomposable base component; and The polar group distribution uniformity, wherein satisfying the uniformity threshold, suppresses aggregation of the PDB component at the bottom of the photoresist layer.

5. The method of claim 1, wherein the photoresist bottom layer comprises at least one of: Middle layer (ML), Bottom layer (BL), or Bottom anti-reflective coating (BARC) layer.

6. The method of claim 1 , wherein performing the processing operation comprises: The thermal treatment operation is performed at a temperature included in a range of greater than about 100 degrees Celsius to about 400 degrees Celsius.

7. The method of claim 1, wherein the processing operation comprises at least one of: Heat treatment operations, Ultraviolet (UV) treatment operations, or Electron beam (e-beam) processing operations.

8. A method comprising: forming a photoresist bottom layer over the substrate, The photoresist bottom layer comprises: a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains; forming a photoresist layer over the photoresist bottom layer; exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; as well as The pattern in the photoresist layer is developed.

9. The method of claim 8, wherein the plurality of acid generator component side chains comprise at least one of: a plurality of hydrocarbon bonded structures, halogens, -S-, -P-, -P(O2)-, -C(=O)S-, -C(=Ohydrocarbon)O-, -O-, -N-, -C(=O)N-, -SO2O-, -SO2S-, -SO-, or -SO2-.

10. A method comprising: forming a photoresist bottom layer over the substrate, The photoresist bottom layer comprises: a polymer backbone, a plurality of acid generator component side chains coupled to the polymer backbone, and an acid generator component coupled to the plurality of acid generator component side chains; performing a processing operation on the photoresist bottom layer, wherein the polar group distribution uniformity on the top surface of the photoresist bottom layer after the treatment operation is greater than the polar group distribution uniformity on the surface of the photoresist layer before the treatment operation; forming a photoresist layer over the photoresist bottom layer after the processing operation; exposing the photoresist layer to radiation to form a pattern in the photoresist layer, wherein the acid generator component in the photoresist bottom layer reacts with radiation to form an acid, the acid causing the pattern to be formed in the photoresist layer; as well as The pattern in the photoresist layer is developed.

Images