Enhancement of EUV underlayer effect by diffusion barrier layer

Abstract

The present disclosure relates to a patterning structure (and methods and apparatus for forming such a structure) that includes a substrate having a partially fabricated semiconductor device film stack, a radiation-sensitive imaging layer over the substrate, an underlayer below the radiation-sensitive imaging layer, the underlayer including an unstable species, a hardmask positioned below the underlayer, and a diffusion barrier layer positioned between the underlayer and the hardmask layer, the diffusion barrier layer including a diffusion barrier material that reduces diffusion of unstable species from the underlayer to the hardmask layer. In various embodiments, the reduced diffusion of unstable species downward from the underlayer to the hardmask results in a relatively greater diffusion of unstable species upward from the underlayer to the radiation-sensitive imaging layer. This increased diffusion into the radiation-sensitive imaging layer may advantageously increase the radiation absorbency and / or patterning performance of the radiation-sensitive imaging layer.

Description

[Technical field]

[0001] Incorporated by reference: As a part of this application, an Application Data Sheet is filed contemporaneously herewith. Each application identified in this contemporaneous filed Application Data Sheet to which this application claims benefit or priority is hereby incorporated by reference in its entirety for all purposes.

[0002] The present disclosure relates generally to the field of semiconductor processing, and more particularly to extreme ultraviolet (EUV) photoresist (PR) lithography techniques and materials. [Background technology]

[0003] As semiconductor fabrication continues to advance, feature sizes continue to shrink, requiring new processing methods. One area where advances are being made is in the area of ​​patterning, for example, using photoresist materials that are sensitive to lithographic radiation.

[0004] The background description provided herein is intended to provide a general overview of the contents of the present disclosure. Work by the currently named inventors within the scope of what is described in this Background section, as well as aspects of the description that may not otherwise be regarded as prior art at the time of filing, are not admitted, expressly or impliedly, as prior art against the present disclosure. Summary of the Invention

[0005] Various embodiments herein relate to methods, materials, devices, and systems for depositing a diffusion barrier layer, or a stack including a diffusion barrier layer, on a substrate. The diffusion barrier layer is provided to reduce or prevent diffusion in one direction, which can promote diffusion in another direction. Control of this diffusion encourages the migration of unstable species within the stack of materials as desired. Such migration can be used to enhance desired properties of the associated materials.

[0006] In one aspect of the disclosed embodiment, a patterning structure is provided, the patterning structure including: a substrate including a partially fabricated semiconductor device film stack; a radiation-sensitive imaging layer disposed over the substrate; an underlayer positioned below the radiation-sensitive imaging layer, the underlayer including an unstable species; a hardmask layer positioned below the underlayer; and a diffusion barrier layer positioned between the underlayer and the hardmask layer, the diffusion barrier layer including a diffusion barrier material that reduces diffusion of the unstable species from the underlayer to the hardmask layer.

[0007] In various implementations, the diffusion barrier material may include a material selected from the group consisting of an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof. For example, in some cases, the diffusion barrier layer may include an oxide material. In some such cases, the oxide material may be a material selected from the group consisting of a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof. In some such cases, the oxide may be a metal oxide. In these or other embodiments, the diffusion barrier material may include a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof. In these or other embodiments, the diffusion barrier material may include a nitride material. In some such cases, the nitride material may be a material selected from the group consisting of a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof. In some such cases, the nitride may be a metal nitride. In some such cases, the diffusion barrier material may include a metal selected from the group consisting of aluminum, molybdenum, tungsten, tin, or combinations thereof. In some cases, the diffusion barrier material may include silicon nitride. In these or other embodiments, the diffusion barrier material may include a carbide material. In some such embodiments, the carbide material may be a material selected from the group consisting of metal carbide, silicon carbide, metal oxycarbide, silicon oxycarbide, or combinations thereof, and optionally, the diffusion barrier material includes a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or combinations thereof. In some such cases, the diffusion barrier material includes silicon carbide. In some such cases, the silicon carbide may be doped. For example, the silicon carbide may be doped with at least one of nitrogen and oxygen.

[0008] In various embodiments, the unstable species may be hydrogen. In these or other embodiments, the radiation-sensitive imaging layer may include a photoresist material. In some such cases, the photoresist material may be a metal-containing photoresist material. In some such cases, the photoresist material is an organometallic-containing photoresist material.

[0009] The underlayer may have various compositions. In various embodiments, the underlayer may include a hydrogen-containing carbon layer including at least one dopant, the at least one dopant being a dopant selected from the group consisting of oxygen, silicon, nitrogen, tungsten, boron, iodine, chlorine, or combinations thereof. In these or other embodiments, the diffusion barrier layer may be deposited using a dry vapor-based deposition technique or using a wet liquid-based deposition technique. In various embodiments, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 60%. In some cases, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 90%.

[0010] In another aspect of the disclosed embodiments, a method of making a patterned structure is provided, the method including providing a substrate having a hard mask layer thereon; depositing a diffusion barrier layer on the hard mask layer, the diffusion barrier layer comprising a diffusion barrier material; depositing an underlayer on the diffusion barrier layer, the underlayer comprising an unstable species; and depositing a radiation-sensitive imaging layer on the underlayer, the diffusion barrier layer reducing diffusion of the unstable species from the underlayer into the hard mask layer.

[0011] In various implementations, the diffusion barrier material may include a material selected from the group consisting of an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof. For example, in some cases, the diffusion barrier layer may include an oxide material. In some such cases, the oxide material may be a material selected from the group consisting of a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof. In some such cases, the oxide may be a metal oxide. In these or other embodiments, the diffusion barrier material may include a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof. In these or other embodiments, the diffusion barrier material may include a nitride material. In some such cases, the nitride material may be a material selected from the group consisting of a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof. In some such cases, the nitride may be a metal nitride. In some such cases, the diffusion barrier material may include a metal selected from the group consisting of aluminum, molybdenum, tungsten, tin, or combinations thereof. In some cases, the diffusion barrier material may include silicon nitride. In these or other embodiments, the diffusion barrier material may include a carbide material. In some such embodiments, the carbide material may be a material selected from the group consisting of metal carbide, silicon carbide, metal oxycarbide, silicon oxycarbide, or combinations thereof, and optionally, the diffusion barrier material includes a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or combinations thereof. In some such cases, the diffusion barrier material includes silicon carbide. In some such cases, the silicon carbide may be doped. For example, the silicon carbide may be doped with at least one of nitrogen and oxygen.

[0012] In various embodiments, the unstable species may be hydrogen. In these or other embodiments, the radiation-sensitive imaging layer may include a photoresist material. In some such cases, the photoresist material may be a metal-containing photoresist material. In some such cases, the photoresist material is an organometallic-containing photoresist material.

[0013] The underlayer may have various compositions. In various embodiments, the underlayer may include a hydrogen-containing carbon layer including at least one dopant, the at least one dopant being a dopant selected from the group consisting of oxygen, silicon, nitrogen, tungsten, boron, iodine, chlorine, or combinations thereof. In these or other embodiments, the diffusion barrier layer may be deposited using a dry vapor-based deposition technique or using a wet liquid-based deposition technique. In various embodiments, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 60%. In some cases, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 90%.

[0014] In another aspect of the disclosed embodiments, an apparatus is provided for fabricating a patterning structure on a substrate, the apparatus including a process chamber including a substrate support, a process gas source and associated flow control hardware connected to the process chamber, and a controller having a processor and a memory, the processor and memory communicatively connected to each other, the processor at least operatively connected to the flow control hardware, and the memory storing computer executable instructions for performing any of the methods recited in the claims or described herein.

[0015] For example, in one embodiment, the memory can store computer-executable instructions for providing a substrate having a hard mask layer thereon to a process chamber, depositing a diffusion barrier layer over the hard mask layer, the diffusion barrier layer comprising a diffusion barrier material, depositing an underlayer over the diffusion barrier layer, the underlayer comprising an unstable species, and depositing a radiation-sensitive imaging layer over the underlayer, where the diffusion barrier layer reduces diffusion of the unstable species from the underlayer into the hard mask layer.

[0016] In a related embodiment, the memory may store a subset of these instructions, for example, for depositing a diffusion barrier layer, optionally in combination with any other instructions described herein.

[0017] In various implementations, the diffusion barrier material may include a material selected from the group consisting of an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof. For example, in some cases, the diffusion barrier layer may include an oxide material. In some such cases, the oxide material may be a material selected from the group consisting of a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof. In some such cases, the oxide may be a metal oxide. In these or other embodiments, the diffusion barrier material may include a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof. In these or other embodiments, the diffusion barrier material may include a nitride material. In some such cases, the nitride material may be a material selected from the group consisting of a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof. In some such cases, the nitride may be a metal nitride. In some such cases, the diffusion barrier material may include a metal selected from the group consisting of aluminum, molybdenum, tungsten, tin, or combinations thereof. In some cases, the diffusion barrier material may include silicon nitride. In these or other embodiments, the diffusion barrier material may include a carbide material. In some such embodiments, the carbide material may be a material selected from the group consisting of metal carbide, silicon carbide, metal oxycarbide, silicon oxycarbide, or combinations thereof, and optionally, the diffusion barrier material includes a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or combinations thereof. In some such cases, the diffusion barrier material includes silicon carbide. In some such cases, the silicon carbide may be doped. For example, the silicon carbide may be doped with at least one of nitrogen and oxygen.

[0018] In various embodiments, the unstable species may be hydrogen. In these or other embodiments, the radiation-sensitive imaging layer may include a photoresist material. In some such cases, the photoresist material may be a metal-containing photoresist material. In some such cases, the photoresist material is an organometallic-containing photoresist material.

[0019] The underlayer may have various compositions. In various embodiments, the underlayer may include a hydrogen-containing carbon layer including at least one dopant, the at least one dopant being a dopant selected from the group consisting of oxygen, silicon, nitrogen, tungsten, boron, iodine, chlorine, or combinations thereof. In these or other embodiments, the diffusion barrier layer may be deposited using a dry vapor-based deposition technique or using a wet liquid-based deposition technique. In various embodiments, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 60%. In some cases, the diffusion barrier layer may reduce the diffusion of unstable species from the underlayer to the hardmask layer by at least about 90%.

[0020] These and other aspects are further described below with reference to the drawings. [Brief description of the drawings]

[0021] [Figure 1A] FIG. 1A is a diagram illustrating a substrate having a stack of materials thereon, the stack of materials being suitable for use in connection with a patterning operation.

[0022] [Figure 1B] FIG. 1B is a diagram showing the concentration profile of unstable species in the stack of materials shown in FIG. 1A, with the pre-diffusion concentration shown. [Figure 1C] FIG. 1C shows the concentration profile of unstable species in the stack of materials shown in FIG. 1A, with post-diffusion concentrations shown.

[0023] [Figure 2A] FIG. 2A is a diagram illustrating a substrate having a stack of materials thereon, the stack of materials including a diffusion barrier layer, suitable for use in connection with a patterning operation.

[0024] [Figure 2B] FIG. 2B shows the concentration profile of unstable species in the stack of materials shown in FIG. 2A, with the pre-diffusion concentration shown. [Figure 2C] FIG. 2C shows the concentration profile of unstable species in the stack of materials shown in FIG. 2A, with post-diffusion concentrations shown.

[0025] [Figure 3A] FIG. 3A illustrates a desired reaction that may occur between the underlayer and the radiation-sensitive imaging layer. [Figure 3B] FIG. 3B illustrates a desired reaction that may occur between the underlayer and the radiation-sensitive imaging layer.

[0026] [Figure 4] FIG. 4 is a flow chart of a method according to various embodiments.

[0027] [Diagram 5] FIG. 5 is a schematic diagram of one embodiment of a process station 500 in accordance with various embodiments.

[0028] [Figure 6] FIG. 6 is a schematic diagram of one embodiment of a multi-station processing tool 600 in accordance with various embodiments.

[0029] [Figure 7] FIG. 7 is a schematic diagram of one embodiment of an inductively coupled plasma device 700 in accordance with various embodiments.

[0030] [Figure 8]FIG. 8 is a schematic diagram of one embodiment of a semiconductor process cluster tool architecture 800 in accordance with various embodiments.

[0031] [Figure 9] FIG. 9 is a cross-sectional schematic diagram of an example dry deposition apparatus 900 according to various embodiments.

[0032] [Figure 10] FIG. 10 is a detailed cross-sectional side view and plan view of a portion of the top plate, substrate, and edge ring shown in FIG.

[0033] [Figure 11] FIG. 11 illustrates experimental results demonstrating the effectiveness of a diffusion barrier layer in reducing unwanted diffusion.

[0034] [Figure 12A] FIG. 12A illustrates the substrate structure evaluated in relation to FIG. [Figure 12B] FIG. 12B illustrates the substrate structure evaluated in relation to FIG. [Figure 12C] FIG. 12C illustrates the substrate structure evaluated in relation to FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. In other instances, well-known process operations have not been described in detail so as not to unnecessarily obscure the disclosed embodiments. While the disclosed embodiments will be described in conjunction with specific embodiments, it will be understood that the specific embodiments are not intended to limit the disclosed embodiments.

[0036] Various embodiments herein relate to methods, apparatus, and structures for improving the efficiency with which a photoresist scanner induces chemical changes in a radiation-sensitive imaging layer. This increased efficiency, often referred to as lower dose-to-size (DtS), generally means that the desired chemical changes during photolithography (and related operations) can be achieved with a relatively lower dose of patterning radiation delivered to the substrate. Such a reduction in radiation dose is of great value in the context of semiconductor patterning, particularly when practicing extreme ultraviolet (EUV) photolithography, which is still relatively costly. To achieve this increased efficiency / lower DtS, diffusion barrier layers are provided in appropriate locations within the film stack on the substrate (e.g., above the hard mask and below the underlayer). The diffusion barrier layers minimize the diffusion of unstable species in a particular direction (e.g., downward into the hard mask) while simultaneously maximizing the diffusion of unstable species in the opposite direction (e.g., upward into the underlayer). This preferential directional diffusion induces the desired chemical changes in the radiation-sensitive imaging layer, resulting in a lower DtS.

[0037] The present disclosure relates to lithographic patterning techniques and materials exemplified by extreme ultraviolet (EUV) lithography, but it should be understood that it is also applicable to other next generation lithography techniques. In addition to EUV, which includes the standard 13.5 nm EUV wavelength currently in use and under development, the most relevant radiation sources for such lithography are DUV (deep UV), which generally refers to the use of 248 nm or 193 nm excimer laser sources, X-ray, which formally includes EUV at the lower energy range of the X-ray range, and e-beam, which can cover a wide energy range. Such methods include contacting a substrate having exposed hydroxyl groups with a hydrocarbyl-substituted tin capping agent to form a hydrocarbyl-terminated tin oxide (SnOx) film as an imaging / PR layer on the surface of the substrate. The specific method may depend on the particular materials and applications used in the semiconductor substrate and the final semiconductor device. Thus, the methods described in this application are merely exemplary of the methods and materials that can be used in the present technology.

[0038] EUV lithography (typically 13.5 nm wavelength) is considered as the next technology to enable lithographic patterning. However, a number of technical obstacles are slowing the widespread adoption and implementation of this technique. EUV photoresist (PR) is one of the barriers.

[0039] Conventional chemically amplified resists (CARs) offer a cost-effective approach. However, organic polymer CARs produce line edge roughness (LER) and line width roughness (LWR) and have sensitivity and resolution limitations due to random variations in the use of polymers. Recent research and development efforts have focused on the development of new EUV inorganic photoresist platforms. Such systems offer several advantages compared to polymer-based CAR systems. These inorganic photoresists are generally based on metal oxides, including metal hydroxide oxides. The small molecular size of metal oxides improves the final resolution of the patterning step, and metal oxide photoresists generally exhibit higher etch resistance than CARs, allowing the thickness of the PR to be reduced to reduce the aspect ratio of the structures.

[0040] FIG. 1A illustrates a substrate 101 having a stack of materials thereon. The substrate may include additional layers depending on the particular purpose. For example, the substrate may be or include amorphous hydrogenated carbon in any form (e.g., bulk film, thin film, another film, stack, etc.), silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon boronitride, amorphous silicon, polysilicon, or any combination described herein. In many cases, the substrate is a partially fabricated semiconductor device, fabricated by any suitable method. As shown in FIG. 1A, the stack includes a hard mask 102, an underlayer 104, and a radiation-sensitive imaging layer 105. The radiation-sensitive imaging layer 105 may also be referred to as a photoresist.

[0041] The hardmask 102 may have various compositions, such as SiO2, silicon nitride, and / or ashable hardmask materials. In some cases, the hardmask 102 may be silicon carbide. Doped versions of these materials may be used in some cases. The hardmask 102 may be formed by chemical vapor deposition (CVD), such as plasma-enhanced CVD (PECVD). Other deposition techniques, such as atomic layer deposition (ALD), plasma-enhanced ALD (PEALD), or reactive physical vapor deposition (PVD), may be used in some cases. An ashable hardmask composed of an amorphous carbon film is desirable in some implementations. The amorphous carbon film in this context may be undoped or may be doped, for example, with boron (B) or tungsten (W). A suitable amorphous carbon film may have a composition including, for example, about 50-80 atomic % carbon (C), 10-20 atomic % hydrogen (H), and 5-40 atomic % B or W dopant. The hardmask 102 may have a minimum thickness of about 10 nm, or about 20 nm, or about 50 nm. In these or other cases, the hardmask 102 may have a maximum thickness of about 1 micron, or about 500 nm, or about 100 nm.

[0042] The underlayer 104 may be or include a hydrogen-containing carbon film doped with oxygen (O), silicon (Si), nitrogen (N), tungsten (W), boron (B), iodine (I), chlorine (Cl), or any combination thereof (e.g., a combination of Si and O). The underlayer 104 may be configured to increase adhesion between the hardmask 102 and the subsequently formed radiation-sensitive imaging layer 105 and reduce the EUV dose for effective EUV exposure of the radiation-sensitive imaging layer. In many embodiments, the underlayer is deposited through a vapor-based technique such as CVD, and possibly PECVD. Other deposition techniques such as ALD, PEALD, physical vapor deposition (PVD), and wet methods such as spin-on deposition may also be used in some cases. In some embodiments, the underlayer deposition process may be integrated as a termination step during the deposition of the hardmask 102. In one embodiment, the underlayer 104 is deposited by introducing or delivering a hydrocarbon precursor (e.g., to provide carbon atoms) and a dopant precursor (e.g., to provide doping non-carbon atoms). In another embodiment, the film is deposited by introducing or delivering a heteroatom-containing precursor, such as an iodine-containing precursor, that provides a doped film after deposition. In particular, hydrogen-containing carbon films doped with iodine can improve secondary electron generation upon exposure to EUV radiation. Other types of precursors and / or dopants can be used depending on the particular application. The underlayer 104 may have a minimum thickness of about 2 nm, or about 5 nm, or about 10 nm, or about 15 nm. The underlayer 104 may have a maximum thickness of 25 nm, or about 20 nm, or about 15 nm, or about 10 nm, or about 5 nm. In many cases, the underlayer 104 may have a thickness of about 2-20 nm. In various cases, the underlayer may include about 0-30 atomic % O and / or about 20-50 atomic % hydrogen (H) and / or 30-70 atomic % C. The underlayer 104 includes one or more unstable species, as described below in connection with Figures 1B and 1C.

[0043] Further details regarding the underlayer 104 are described in International Patent Application No. PCT / US2021 / 012953, entitled "UNDERLAYER FOR PHOTORESIST ADHESION AND DOSE REDUCTION," filed on January 11, 2021 and published as WO2021 / 146138, the disclosure of which is incorporated herein by reference in its entirety.

[0044] Returning to the embodiment of Figure 1A, the stack of materials further includes a radiation-sensitive imaging layer 105. The radiation-sensitive imaging layer 105 may include, for example, an EUV-sensitive inorganic photoresist. A suitable EUV-sensitive inorganic photoresist may be a metal oxide film, such as an EUV-sensitive tin oxide-based photoresist. Such resists (also referred to as imaging layers) and their formation and use are described, for example, in International Patent Application No. PCT / US2019 / 031618, entitled "METHODS FOR MAKING EUV PATTERNABLE HARD MASKS," filed May 9, 2019, and published as WO2019 / 217749, and PCT / US2019 / 060742, entitled "METHODS FOR MAKING HARD MASKS USEFUL IN NEXT GENERATION LITHOGRAPHY," filed November 11, 2019, and published as WO2020 / 102085, the disclosures of which relating to the composition, deposition, and patterning of directly photopatternable metalorganic-based metal oxide films to form EUV resist masks are incorporated herein by reference. As described herein, according to various embodiments, the radiation-sensitive inorganic photoresist may be a spin-on film (e.g., deposited using a wet technique) or a vapor-deposited film (e.g., deposited using a dry technique). If vapor deposition is used, the radiation-sensitive imaging layer 105 may be formed through a variety of techniques, such as CVD, PECVD, ALD, PEALD, self-assembled monolayer (SAM), or through a wet technique, such as spin-on deposition. In some embodiments, the radiation-sensitive imaging layer 105 may be another type of imaging layer, such as a conventional CAR or other type of photoresist, and may also be formed through any of the dry or wet deposition methods described above.

[0045] In some embodiments, the radiation-sensitive imaging layer 105 is a metal oxypolymer photoresist. In many such cases, the photoresist structure includes metal atoms surrounded by one or more radiation decomposable ligands. The cleaved metal atoms crosslink within the photoresist structure with the assistance of unstable species originating from the underlayer 104 (e.g., after exposure to patterning radiation). As previously mentioned, other types of photoresists may be used in some cases.

[0046] In many cases, the radiation-sensitive imaging layer 105 is a polymeric and / or polymerizable material. The radiation-sensitive imaging layer 105 may include one or more materials that are photopolymerizable, photodegradable, and / or photocrosslinkable. In various embodiments, the radiation-sensitive imaging layer 105 may be a positive photoresist or a negative photoresist. One exemplary positive photoresist is a diazonaphthoquinone (DNQ)-novolac photoresist. Exemplary negative photoresists include epoxy-based polymers, such as SU-8 photoresist available from Kayaku Advanced Materials, Westborough, Massachusetts, non-stoichiometric thiol-ene (OSTE) polymers available from Mercene Labs, Stockholm, Sweden, and methyl methacrylate. Other exemplary photoresist materials include, but are not limited to, combinations of woven glass and epoxy (e.g., FR-4, FR-5, G-10), cotton paper and epoxy (e.g., FR-6, CEM-1), woven glass and polyester (e.g., CEM-5), and the like.

[0047] 1A also illustrates, for reference, the interfaces between the various materials in the stack. For example, interface 111 is the interface between substrate 101 and hardmask 102, interface 112 is the interface between hardmask 102 and underlayer 104, and interface 114 is the interface between underlayer 104 and radiation-sensitive imaging layer 105.

[0048] As previously mentioned, the underlayer 104 includes one or more labile species. In many embodiments, the labile species is hydrogen. Other labile species that may be used in various embodiments include, but are not limited to, isotopes of hydrogen (e.g., also known as deuterium). 2 Also called H, and / or tritium 3 H), oxygen (e.g. 16 O. 17 O, and / or 18 The unstable species may include, for example, alkyl, aryl, aryl groups (e.g., --O), and / or hydroxyl groups (e.g., --OH). Over time and / or upon application of energy, some of the unstable species begin to migrate from the underlying layer 104. For example, some of the unstable species may diffuse upward into the radiation-sensitive imaging layer 105, while some of the unstable species may diffuse downward into the hard mask 102.

[0049] FIG. 1B shows the concentration profile of the unstable species at different locations in the stack of materials shown in FIG. 1A before substantial diffusion of the unstable species. FIG. 1C shows the concentration profile of the unstable species at different locations in the stack of materials shown in FIG. 1A after some diffusion of the unstable species. The interfaces 111, 112, and 114 shown in FIG. 1A are also shown in FIG. 1B and FIG. 1C for reference. As shown in FIG. 1B, before diffusion, the unstable species are substantially concentrated in the underlayer 104 between the interfaces 112 and 114. As shown in FIG. 1C, after diffusion, the unstable species are also present in the radiation-sensitive imaging layer 105 (e.g., above the interface 114) and the hard mask layer 102 (e.g., below the interface 112). The concentration of the unstable species is highest at the interfaces 112 and 114 and decreases away from the underlayer 104. Such diffusion can occur with the application of energy and over time in the presence of concentration differences.

[0050] Diffusion of unstable species from the underlayer 104 can be beneficial. For example, it has been shown that interaction between the underlayer 104 and the radiation-sensitive imaging layer 105 results in a reduction in DtS. This means that the same or improved imaging results can be achieved with less radiation than would be required if the underlayer 104 were not present. Without wishing to be bound by theory or mechanism of action, diffusion of unstable species (such as, for example, hydrogen) provides one possible mechanism for facilitating interaction between (i) unstable species originating from the underlayer 104 and (ii) metal atoms (or other species) in the radiation-sensitive imaging layer 105.

[0051] While it is beneficial for unstable species to diffuse upward from underlayer 104 into radiation-sensitive imaging layer 105, it is not beneficial for such species to diffuse downward into hardmask 102. Therefore, a diffusion barrier layer can be provided between underlayer 104 and hardmask 102, as shown in Figure 2A.

[0052] FIG. 2A illustrates a substrate 201 having a stack of materials thereon according to various embodiments herein. The stack of materials includes a hard mask 202, a diffusion barrier layer 203, an underlayer 204, and a radiation-sensitive imaging layer 205. The substrate may include additional layers for specific purposes. In general, the hard mask 202 is similar to the hard mask 102, the underlayer 204 is similar to the underlayer 104, and the radiation-sensitive imaging layer 205 is similar to the radiation-sensitive imaging layer 105. Unless otherwise specified, details regarding any of the layers of the embodiment of FIG. 1A may also apply to the analogous layers of the embodiment of FIG. 1B. For the sake of brevity, such details will not be repeated here.

[0053] The diffusion barrier layer 203 can include a variety of compositions. For example, the diffusion barrier layer 203 may include an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof. In various cases where the diffusion barrier layer 203 includes an oxide material, the oxide may be or include a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof. In various cases where the diffusion barrier layer 203 includes a metal (e.g., in the form of a metal oxide, a metal oxynitride, a metal oxycarbide, etc.), the metal may be selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof. In various cases where the diffusion barrier layer 203 includes a nitride material, the nitride may be or include a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof. In various cases where the diffusion barrier layer 203 includes a metal (e.g., in the form of a metal nitride or metal oxynitride), the metal may be selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or combinations thereof. In various embodiments where the diffusion barrier layer 203 includes a carbide material, the carbide may be or include a metal carbide, silicon carbide, metal oxycarbide, silicon oxycarbide, or combinations thereof. When the diffusion barrier layer 203 includes a metal (e.g., in the form of a metal carbide or metal oxycarbide), the metal may be selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or combinations thereof. The diffusion barrier layer 203 may be undoped in some embodiments. In other embodiments, the diffusion barrier layer 203 may be doped with one or more dopants. Exemplary dopants include, but are not limited to, oxygen and nitrogen. In certain embodiments, the diffusion barrier layer 203 is silicon carbide. In another particular embodiment, the diffusion barrier layer 203 is silicon carbide doped with oxygen. In another particular embodiment, the diffusion barrier layer 203 is silicon carbide doped with nitrogen. In yet another particular embodiment, the diffusion barrier layer 203 is silicon carbide doped with nitrogen and oxygen.

[0054] The diffusion barrier layer 203 can be formed in a number of ways. Often, vapor-based deposition techniques are used. Exemplary techniques include CVD, PECVD, ALD, PEALD, PVD, and the like. In other cases, wet deposition techniques such as spin-on deposition may be used. In certain embodiments, the diffusion barrier layer 203 may have a particular thickness. For example, the diffusion barrier layer may have a minimum thickness of about 3 nm, or about 5 nm, or about 10 nm, or about 20 nm. In these or other embodiments, the diffusion barrier layer may have a maximum thickness of about 100 nm, or about 75 nm, or about 50 nm, or about 10 nm. The thickness of the diffusion barrier layer 203 depends on the material used for this layer. For example, as described below with reference to the experimental results in Table 1, a diffusion barrier layer of aluminum oxide having a thickness of 100 Å performed better than a diffusion barrier layer of nitrogen-doped silicon carbide having a thickness of 250 Å under the same conditions. It is therefore believed that metal-containing diffusion barrier layers may be effective at smaller thicknesses than other types of diffusion barrier layers, such as those containing silicon.

[0055] Deposition conditions for forming the diffusion barrier layer 203 vary depending, for example, on the material of the diffusion barrier layer 203 and the technique used for deposition. Exemplary deposition temperatures may be as low as about 50° C. to 375° C., and / or as high as about 300° C. to 400° C. Exemplary deposition pressures may be as low as about 5 mTorr to about 900 mTorr, and / or as high as about 1 Torr to about 300 Torr. When plasma is used, various types of plasma may be used, including, but not limited to, capacitively coupled plasma, inductively coupled plasma, and transformer coupled plasma. The plasma may be generated at one or more frequencies, such as 13.56 MHz and / or 27 MHz. The plasma may be generated at a particular power level. This power level may be as low as about 10 W to about 90 W. In these or other cases, the power level may be as high as about 100 W to about 10 kW. These power levels refer to the power supplied to process a single 300 mm diameter substrate and may be linearly scaled based on the substrate surface area for other size substrates. If a plasma is used, the plasma may be continuous or pulsed (e.g., at frequencies as low as about 1 Hz and as high as about 10 kHz) with duty cycles as low as about 1% and as high as about 99%. In some cases, a bias may be applied to the substrate during deposition, for example to control ion energy or other factors. Such a bias may be continuous or pulsed as well.

[0056] The precursors used to form the diffusion barrier layer 203 can include any combination of precursors that result in the formation of the materials listed for the diffusion barrier layer 203. For example, if the diffusion barrier layer 203 includes an oxide material, an oxygen-containing precursor is provided. Similarly, if the diffusion barrier layer 203 includes a nitride material, a nitrogen-containing precursor is provided, if the diffusion barrier layer 203 includes a carbide material, a carbon-containing precursor is provided, if the diffusion barrier layer 203 includes a metal, a metal-containing precursor is provided, if the diffusion barrier layer 203 includes a silicon or silicide material, a silicon-containing precursor is provided, and if the diffusion barrier layer 203 includes a sulfide material, a sulfur-containing precursor is provided. Such precursors can be combined depending on the particular application.

[0057] The diffusion barrier layer 203 can have specific properties in various embodiments. Since the diffusion barrier layer 203 is provided primarily to minimize diffusion in a particular direction, the diffusion barrier layer 203 must be effective in preventing or reducing the migration of unstable species at the relevant processing conditions. As previously mentioned, in many cases the unstable species is hydrogen. In such cases, the diffusion barrier 203 layer must be effective in reducing the migration of hydrogen from the underlayer 204 to the hardmask 202. The diffusion of unstable species in the embodiment of FIG. 2A is further described below with reference to FIGS. 2B and 2C.

[0058] Experimental results demonstrating the effectiveness of certain materials as diffusion barrier layers in reducing the diffusion of unstable species are discussed below in conjunction with FIG. 11, Equation 1, and Table 1. In various embodiments, the diffusion barrier layer is effective in reducing the diffusion of unstable species (e.g., hydrogen and / or other) by at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 95%. This reduction in diffusion (H blocking ) can be calculated according to Equation 1, further described below. The reduction in diffusion values ​​provided herein may be applied at a particular temperature, such as about 100° C., 200° C., 300° C., 350° C., 400° C., 450° C., about 500° C., or a temperature between any two of such temperatures.

[0059] The diffusion barrier layer 203 should also be compatible with its adjacent materials in the stack on the substrate. This helps to avoid undesired reactions and maintain high quality results. This compatibility should apply in terms of both composition and processing conditions. With respect to processing conditions, for example, certain hard mask materials have temperature limitations and / or thermal budgets that should not be exceeded. In various embodiments, the amorphous carbon hard mask should not be exposed to temperatures above about 360° C. In such embodiments, the temperature at which the diffusion barrier layer 203 is formed should be about 360° C. or less.

[0060] In various embodiments, the diffusion barrier layer 203 has an amorphous morphology, which can facilitate high quality pattern transfer through associated layers.

[0061] The diffusion barrier layer 203 must have a composition that allows it to be etched with high selectivity using appropriate chemistries that are compatible with the remaining materials in the stack, if necessary. Relatedly, the diffusion barrier layer 203 must be compatible with the etch chemistries used to transfer patterns between the diffusion barrier layer 203 and its adjacent layers. Often, halide-containing etch chemistries can be used to transfer patterns between associated layers in the stack on the substrate. Exemplary halide-containing etch chemistries include fluorine-containing etch chemistries (e.g., CF4, CHF3, CH3F, CH2F2, C4F8, HF, NF3, and SF6, etc.), bromine-containing etch chemistries (e.g., BCl3, etc.), and chlorine-containing etch chemistries (e.g., Cl2, HCl, BCl3, etc.).

[0062] In some cases, the diffusion barrier layer 203 may have a particular density. An exemplary minimum density includes, for example, about 1 g / cm 3 , or about 2 g / cm 3 Exemplary maximum densities include, for example, about 10 g / cm3 , or about 5 g / cm 3 Examples include:

[0063] Another consideration that may influence the choice of material for the diffusion barrier layer 203 is cost. In various embodiments, a relatively inexpensive material may be preferred, for example, because it can be fabricated using commonly available or easily manufacturable materials. Similarly, in certain embodiments, a material / material that is relatively safe to work with may be preferred.

[0064] In various embodiments, the diffusion barrier layer 203 is deposited as a homogeneous layer. In some other embodiments, the diffusion barrier layer 203 may be deposited as a non-homogeneous layer. For example, the diffusion barrier layer 203 may be deposited to include a gradient in one or more components (e.g., oxygen, nitrogen, carbon, silicon, metal, sulfur, or a material including any one or more of these elements). In some embodiments, the diffusion barrier layer 203 may be deposited as two or more layers, each independently having any of the diffusion barrier layer compositions described herein. As previously mentioned, in some cases, the diffusion barrier layer 203 is doped. Such doping may be homogeneous or graded (e.g., a higher or lower concentration of dopant near interface 212 compared to interface 213 in a direction perpendicular to the layer). When the diffusion barrier layer 203 includes two or more layers, the doping may be present in some or all of these layers. In certain examples, the doping may be limited to the top or bottom layer of the diffusion barrier layer 203.

[0065] FIG. 2B shows the concentration profile of the unstable species at different locations in the stack of materials shown in FIG. 2A before substantial diffusion of the unstable species. FIG. 2C shows the concentration profile of the unstable species at different locations in the stack of materials shown in FIG. 2A after some diffusion of the unstable species. The interfaces 211, 212, 213, and 214 shown in FIG. 2A are also shown in FIG. 2B and FIG. 2C for reference. As shown in FIG. 2B, before diffusion, the unstable species are substantially concentrated in the underlayer 204 between the interfaces 213 and 214. As shown in FIG. 2C, after diffusion, the unstable species are also present in the radiation-sensitive imaging layer 205 (e.g., above the interface 214). Within the radiation-sensitive imaging layer 205, the concentration of the unstable species is highest at the interface 214 and decreases away from the underlayer 204. Such diffusion may occur due to the application of energy and / or the passage of time.

[0066] In particular, FIG. 2C shows that after diffusion, there are few or no unstable species in the diffusion barrier layer 203 (e.g., between interfaces 212 and 213) or in the hard mask 202 (e.g., below interface 212). The presence of the diffusion barrier layer 203 substantially reduces or avoids diffusion of unstable species downward from the underlayer 204 into the diffusion barrier layer 203 and hard mask 202. As a result, there are more unstable species migrating upward from the underlayer 204 into the radiation sensitive imaging layer 205. Compared to FIG. 1C, FIG. 2C shows a relatively large diffusion of unstable species into the radiation sensitive imaging layer 105 / 205. As previously discussed, this migration of unstable species into the radiation sensitive imaging layer 205 is beneficial at least because it results in a lower DtS than would be required if the diffusion barrier layer 203 were not present.

[0067] 3A and 3B show desirable reactions between the underlayer and the radiation-sensitive imaging layer. These reactions are driven by the diffusion of unstable species from the underlayer to the radiation-sensitive imaging layer and from the radiation-sensitive imaging layer to the underlayer. The use of a diffusion barrier layer below the underlayer further increases the amount of diffusion of unstable species upward into the radiation-sensitive imaging layer, as discussed above.

[0068] 3A and 3B include migration (or diffusion) of metal (M) atoms from the imaging layer 305 to the underlayer 304, and / or migration (or diffusion) of unstable species (e.g., hydrogen (H) atoms in this example) from the underlayer 304 to the radiation-sensitive imaging layer 305. Without wishing to be limited by mechanism, such migration events can provide productive interactions between the underlayer and the imaging layer, which can contribute to improved adhesion and / or DtS.

[0069] In addition, the composition of the underlayer and imaging layer can be designed to promote favorable reactions, thereby improving DtS. For example, as seen in FIG. 3A, the imaging layer can include a tin-based photoresist with radiation-cleavable ligands (R). Upon exposure to radiation (e.g., EUV), the ligands are displaced from the metal centers (e.g., often tin centers) and in their place, M-H bonds (e.g., Sn-H bonds) are formed. After a post-exposure bake (PEB) step, the M-H bonds participate in further thermally activated crosslinking reactions, thereby increasing the difference in material properties between the exposed and unexposed photoresists.

[0070] Thus, in one example, as seen in FIG. 3B, the underlayer 304 can include a ligand (R1) that provides a releasable unstable species (e.g., H atom or other unstable species) upon exposure to EUV radiation, thereby forming a reacted ligand (R1*). Possible R1 groups include, for example, optionally substituted alkyl, which can be linear or branched. In the radiation-sensitive imaging layer 305, the EUV-cleavable ligand R provides a leaving ligand R* and a reactive metal center (M, e.g., Sn). The released unstable species (e.g., H atom) from the underlayer 304 can facilitate the formation of a bond in the radiation-sensitive imaging layer 305, which bond is between a metal from the radiation-sensitive imaging layer 305 and an unstable species from the underlayer 304 (e.g., a M-H bond, such as a Sn-H bond in this example), thereby reducing DtS. If underlayer 304 also contains oxygen (O) atoms, such atoms can form MO bonds (e.g., Sn-O bonds) within radiation-sensitive imaging layer 305, which can further reduce DtS. Additionally, metal atoms (e.g., Sn atoms) from radiation-sensitive imaging layer 305 can diffuse into underlayer 304, thereby enabling the generation of additional secondary electrons.

[0071] FIG. 4 provides a flow chart illustrating a method of processing a partially fabricated semiconductor device according to various embodiments. The method may be practiced in connection with patterning applications, for example, to define and etch a pattern on a surface of a substrate. The method is described with reference to the structure shown in FIG. 2A. Any of the details provided above with respect to the structure shown in FIG. 2A (and the analogous layers of FIG. 1A) may be applied when practicing the method of FIG. 4. Similarly, any of the details provided with respect to FIGS. 3A and 3B may be applied when practicing the method of FIG. 4. The method of FIG. 4 begins with operation 401, where a diffusion barrier layer 203 is deposited on a hard mask 202.

[0072] Next, in operation 403, underlayer 204 is deposited on diffusion barrier layer 203. Then, in operation 405, radiation-sensitive imaging layer 205 is deposited on underlayer 204. At this point, the stack of materials on substrate 201 is complete and substrate 201 can be processed using photolithography. In operation 407, radiation-sensitive imaging layer 205 is patterned, for example, by selectively exposing radiation-sensitive imaging layer 205 to radiation and subsequently developing the pattern by selectively etching either the exposed or unexposed portions of radiation-sensitive imaging layer 205. Development may be done by dry techniques, wet techniques, or a combination thereof.

[0073] Although not shown in FIG. 4, one or more additional operations may be performed to promote high quality pattern formation / transfer. Such operations generally include baking the substrate at an elevated temperature, possibly under a controlled atmosphere. One such operation is called a post-apply bake (PAB), which may be performed after the radiation-sensitive imaging layer is deposited in operation 405 and before the radiation-sensitive imaging layer is exposed to radiation in operation 407. Another such operation is called a post-exposure bake (PEB), which may be performed after the radiation-sensitive imaging layer is exposed to radiation in operation 407. Another such operation is called a post-development bake (PDB), which may be performed after the radiation-sensitive imaging layer is developed following exposure to radiation in operation 407. Certain chemical changes that may occur during baking operations are further described in connection with FIGS. 3A and 3B above.

[0074] For post-application treatments (e.g., PAB), thermal processes that control temperature, gas atmosphere (e.g., air, HO, CO, CO, O, O, CH, CHOH, N, H, NH, NO, NO, Ar, He, or mixtures thereof) or under vacuum, and moisture can be used after deposition and before exposure to change the composition of the unexposed metal and / or metal oxide or other materials in the radiation-sensitive imaging layer 205. This change can increase the EUV sensitivity of the material, and thus achieve reduced DtS and edge roughness after exposure and development. For post-exposure treatments (e.g., PEB), thermal processes that control temperature, gas atmosphere (e.g., air, HO, CO, CO, O, O, CH, CHOH, N, H, NH, NO, NO, Ar, He, or mixtures thereof) or under vacuum, and moisture can be used to change the composition of both the unexposed and exposed portions of the radiation-sensitive imaging layer 205. This change can increase the difference in composition / material properties between the unexposed and exposed materials, and the difference in the etch rate of the dry development etch gas between the unexposed and exposed materials. Higher etch selectivity can thereby be achieved. Improved selectivity can result in a more square PR profile with improved surface roughness and / or less photoresist residue / scum. In certain embodiments, PEB can be performed in air, optionally with moisture and CO2. For post-development treatments (e.g., PDB), the composition of the remaining portion of the radiation-sensitive imaging layer 205 can be changed using a thermal process that controls temperature, gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or mixtures thereof) or under vacuum (e.g., using UV), and moisture. In certain embodiments, PDB also includes the use of plasma (e.g., including O2, O3, Ar, He, or mixtures thereof). PDB can increase the hardness of the material, which can be beneficial when the film is used as a resist mask in etching the underlying substrate.In various cases, alternative embodiments may replace the thermal processes described herein with remote plasma processes to increase the reactive species, lower the energy barrier to reaction, and increase productivity. Remote plasmas can generate more reactive radicals, thus lowering the reaction temperature / time for processing, leading to increased productivity.

[0075] Yet other steps may include in situ metrology capable of assessing physical and structural properties (e.g., critical dimensions, film thickness, etc.) during the photolithography process. Modules for performing in situ metrology may include, for example, a scatterometry module, an ellipsometry module, a downstream mass spectrometry module, and / or a plasma-enhanced downstream optical emission spectroscopy module.

[0076] Returning to the embodiment of Figure 4, in operation 409, the pattern formed in the radiation-sensitive imaging layer is transferred through the underlayer 204, the diffusion barrier layer 203, and the hard mask 202 to the substrate 201. One or more etching processes may be performed to transfer the desired pattern through the associated layers. In many embodiments, a plasma-based etching operation is used.

[0077] Related embodiments may include substantially fewer steps. For example, one embodiment includes operation 401 (e.g., deposition of a diffusion barrier layer) without other steps. Other embodiments may include operation 401 in combination with any one or more of the other steps described in connection with FIG.

[0078] Device The present disclosure also includes any apparatus configured to perform any of the methods described herein. In one embodiment, an apparatus for depositing a film includes a deposition module comprising a chamber for depositing one or more precursors to provide a hard mask, a diffusion barrier layer, an underlayer, and / or an imaging layer, a patterning module comprising an EUV photolithography tool having a radiation source with a wavelength of less than 30 nm, and a development module comprising a chamber for developing the film including such layers.

[0079] The apparatus may further include a controller having instructions for such modules. In one embodiment, the controller includes one or more memory devices, one or more processors, and system control software coded with instructions for performing deposition of the film. These may include instructions in a deposition module for depositing one or more precursors to provide a diffusion barrier layer, an underlayer, and / or an imaging layer, instructions in a patterning module for patterning a layer with a resolution of less than 30 nm directly by EUV exposure, thereby forming a pattern in the film, and instructions in a development module for developing the film. In a particular embodiment, the development module performs removal of EUV exposed or non-EUV exposed areas, thereby providing a pattern in the film.

[0080] 5 illustrates a schematic diagram of one embodiment of a process station 500 having a process chamber body 502 for maintaining a low pressure environment suitable for carrying out the described vapor deposition and dry development embodiments described herein. Multiple process stations 500 may be included in a common low pressure process tool environment. For example, FIG. 6 illustrates one embodiment of a multi-station processing tool 600. In some embodiments, one or more hardware parameters of the process stations 500 (including those described in detail below) may be programmatically adjusted by one or more computer controllers 550.

[0081] The process stations can be configured as modules within a cluster tool. Figure 8 illustrates a semiconductor process cluster tool architecture having a vacuum integrated deposition and patterning module suitable for implementing the embodiments described herein. Such a cluster process tool architecture can include a PR and underlayer deposition module, a resist exposure (EUV scanner) module, a resist dry development module, and an etch module, as described above and further below with reference to Figures 7 and 8.

[0082] In some embodiments, certain processing functions, such as vapor deposition (e.g., PECVD), dry development, and etching, can be performed sequentially in the same module. Also, embodiments of the present disclosure are directed to an apparatus for processing a substrate, the apparatus having a process chamber with a substrate support, a process gas source and associated flow control hardware connected to the process chamber, substrate handling hardware connected to the process chamber, and a controller having a processor and a memory. In some implementations, the processor and memory are communicatively connected to each other, the processor is at least operatively connected to the flow control hardware and the substrate handling hardware, and the memory stores computer-executable instructions for performing operations in the methods of fabricating a patterned structure described herein.

[0083] For example, the memory can store computer executable instructions for providing a hardmask disposed on the substrate, for example, by chemical vapor deposition (e.g., PECVD). As described above, a suitable hardmask may be, for example, an ashable hardmask film of amorphous carbon, undoped or doped with B or W. The memory can further store instructions for depositing a diffusion barrier layer on the hardmask / substrate. Suitable diffusion barrier layers are further described above.

[0084] The memory can further store instructions for depositing an underlayer over the substrate and / or diffusion barrier layer, the underlayer configured to reduce EUV dose for effective EUV exposure of the photoresist and in some cases promote adhesion between associated layers.

[0085] The memory can further store instructions for forming an EUV-sensitive inorganic photoresist over the photoresist underlayer. A suitable EUV-sensitive inorganic photoresist can be a metal oxide film, such as an EUV-sensitive tin oxide-based photoresist as described above.

[0086] Returning to Figure 5, the process station 500 is in fluid communication with a reactant delivery system 501a for delivering process gases to a distribution showerhead 506. The reactant delivery system 501a optionally includes a mixing vessel 504 for blending and / or adjusting the process gases delivered to the showerhead 506. One or more mixing vessel inlet valves 520 can control the introduction of process gases to the mixing vessel 504. If plasma exposure is used, the plasma can also be delivered to the showerhead 506 or can be generated in the process station 500.

[0087] 5 includes an optional vaporization point 503 for vaporizing the liquid reactant provided to the mixing vessel 504. In some embodiments, a liquid flow controller (LFC) can be provided upstream of the vaporization point 503 to control the mass flow rate of the liquid that is vaporized and delivered to the process station 500. For example, the LFC can include a thermal mass flow meter (MFM) located downstream of the LFC. A plunger valve of the LFC can then be adjusted in response to a feedback control signal provided by a proportional-integral-derivative (PID) controller in electrical communication with the MFM.

[0088] 5, the substrate 512 is shown positioned below the showerhead 506 and resting on a pedestal 508. The showerhead 506 may have any suitable shape and may have any suitable number and arrangement of ports for distributing process gases to the substrate 512.

[0089] In some embodiments, the pedestal 508 can be raised or lowered to expose the substrate 512 to the volume between the substrate 512 and the showerhead 506. It will be appreciated that in some embodiments, the height of the pedestal can be programmatically adjusted by a suitable computer controller 550.

[0090] In some embodiments, the pedestal 508 may be temperature controlled via heater 510. In some embodiments, the pedestal 508 may be heated to a temperature of greater than 0° C. to 300° C. or greater, such as 50-120° C., for example about 65-80° C., during non-plasma thermal exposure of the photopatterned resist to a hydrogen halide dry developing chemistry, such as HBr or HCl.

[0091] Additionally, in some embodiments, pressure control for the process station 500 may be provided by a butterfly valve 518. As shown in the embodiment of Figure 5, the butterfly valve 518 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some embodiments, pressure control for the process station 500 may also be adjusted by varying the flow rate of one or more gases introduced to the process station 500.

[0092] In some embodiments, the position of the showerhead 506 can be adjusted relative to the pedestal 308 to vary the volume between the substrate 512 and the showerhead 506. Further, it will be appreciated that the vertical position of the pedestal 508 and / or the showerhead 506 may be varied by any suitable mechanism within the scope of the present disclosure. In some embodiments, the pedestal 508 may include a rotational axis for rotating the orientation of the substrate 512. It will be appreciated that in some embodiments, one or more of these exemplary adjustments can be implemented programmatically by one or more suitable computer controllers 550.

[0093] Where plasma may be used, for example in a mild plasma-based dry development embodiment and / or an etching operation performed in the same chamber, the showerhead 506 and pedestal 508 are in electrical communication with an RF power source 514 and a matching network 516 to power the plasma. In some embodiments, the plasma energy may be controlled by controlling one or more of the process station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing. For example, the RF power source 514 and the matching network 516 may operate at any suitable power to form a plasma having a desired composition of radical species. An example of a suitable power is up to about 500 W. Similarly, the RF power source 514 may provide RF power of any suitable frequency. In some embodiments, the RF power source 514 may be configured to control high and low frequency RF power sources independently of one another. Examples of low frequency RF frequencies may include, but are not limited to, frequencies between 50 kHz and 1000 kHz. Examples of high frequency RF frequencies may include, but are not limited to, frequencies between 1.8 MHz and 2.45 GHz (e.g., about 13.56 MHz). It will be appreciated that any suitable parameter may be adjusted discretely or continuously to provide plasma energy for surface reactions. In one non-limiting example, the plasma power may be intermittently pulsed to reduce ion bombardment at the substrate surface compared to a continuously powered plasma. The RF power source may be operated at any suitable duty cycle. Examples of suitable duty cycles include, but are not limited to, a duty cycle between about 5% and 90%. Acceptable process pressures are between about 20 mTorr and 5 Torr.

[0094] In some examples, the RF power can be continuous or pulsed between one or more levels. If pulsed operation is used, the pulsing can be performed at a frequency ranging from 1 Hz to 1 MHz. In some examples, the chamber pressure is maintained at a predetermined pressure ranging from 5 mTorr to 450 mTorr. In other examples, the deposition and processing is performed at a pressure ranging from 5 mTorr to 150 mTorr. In yet other examples, the deposition and processing is performed at a pressure ranging from 5 mTorr to 35 mTorr.

[0095] In some deposition processes, the plasma strike lasts for several seconds or more in duration. In certain implementations, much shorter plasma strikes may be used. These may be on the order of 10 ms to 1 second, typically about 20 to 80 ms, with 50 ms being a specific example. Such very short RF plasma strikes require extremely rapid stabilization of the plasma. To achieve this, the plasma generator may be configured such that the impedance match is preset to a particular voltage while the frequency is allowed to vary. Conventionally, high frequency plasmas are generated at an RF frequency of about 13.56 MHz. In various embodiments disclosed herein, the frequency is allowed to vary to values ​​different from this standard value. By allowing the frequency to vary while the impedance match is fixed at a predetermined voltage, the plasma can be stabilized much more quickly, which may be important when using very short plasma strikes associated with certain types of deposition cycles.

[0096] In some embodiments, instructions for the controller 550 may be provided via input / output control (IOC) sequence instructions. In one example, instructions for setting conditions for a process step may be included in a corresponding recipe step of a process recipe. In some cases, a process recipe step may be arranged in sequence such that all instructions for a process step are executed simultaneously with that process step. In some embodiments, instructions for setting one or more reactor parameters may be included in a recipe step. For example, a recipe step may include instructions for setting flow rates of a first reactant and a second reactant to form a diffusion barrier layer or any of the other layers described herein. In some embodiments, the controller 550 may include any of the features described below with respect to the system controller 550 of FIG. 6.

[0097] As mentioned above, one or more process stations can be included in a multi-station processing tool. FIG. 6 shows a schematic diagram of an embodiment of a multi-station processing tool 600 with an inbound load lock 602 and an outbound load lock 604, either or both of which may include a remote plasma source. A robot 606 is configured to move a wafer from a cassette loaded via a pod 608 at atmospheric pressure to the inbound load lock 602 via an atmospheric pressure port 610. The wafer is placed by the robot 606 on a pedestal 612 of the inbound load lock 602, the atmospheric pressure port 610 is closed, and the load lock is pumped down. If the inbound load lock 602 includes a remote plasma source, the wafer may be subjected to a remote plasma treatment to treat a surface within the load lock before being introduced to the processing chamber 614. Additionally, the wafer may also be heated in the inbound load lock 602 to remove, for example, moisture and absorbed gases. A chamber transfer port 616 to the processing chamber 614 is then opened and another robot (not shown) places the wafer into the reactor on the pedestal of the first station shown in the reactor for processing. Although the embodiment shown in Figure 6 includes a load lock, it will be understood that in some embodiments the wafer may enter the process station directly.

[0098] The illustrated processing chamber 614 includes four process stations, numbered 1 through 4 in the embodiment shown in FIG. 6. Each station has a heated pedestal (shown at 618 for station 1) and a gas line inlet. It will be appreciated that in some embodiments, each process station may have a different purpose or multiple purposes. For example, in some embodiments, a process station may be switchable between a dry development mode and an etch process mode. Additionally or alternatively, in some embodiments, the processing chamber 614 may include one or more corresponding pairs of dry development and etch process stations. While the illustrated processing chamber 614 includes four stations, it will be appreciated that a processing chamber according to the present disclosure may have any suitable number of stations. For example, in some embodiments, the processing chamber may have five or more stations, while in other embodiments, the processing chamber may have three or fewer stations.

[0099] FIG. 6 illustrates one embodiment of a wafer handling system 690 for transferring wafers within the processing chamber 614. In some embodiments, the wafer handling system 690 can transfer wafers between various process stations and / or between process stations and load locks. It will be understood that any suitable wafer handling system may be used. Non-limiting examples include a wafer carousel and a wafer handling robot. FIG. 6 also illustrates one embodiment of a system controller 650 used to control the process conditions and hardware states of the process tool 600. The system controller 650 can include one or more memory devices 656, one or more mass storage devices 654, and one or more processors 652. The processor 652 can include a CPU or computer, analog and / or digital input / output connections, stepper motor controller boards, etc.

[0100] In some embodiments, the system controller 650 controls all of the activity of the process tool 600. The system controller 650 executes system control software 658 that is stored in the mass storage device 654, loaded into the memory device 656, and executed on the processor 652. Alternatively, the control logic may be hard-coded into the controller 650. Application specific integrated circuits, programmable logic devices (e.g., field programmable gate arrays, or FPGAs), and the like may be used for these purposes. In the following description, wherever "software" or "code" is used, functionally equivalent hard-coded logic may be used instead. The system control software 658 may include instructions for controlling the timing, mixture of gases, gas flow rates, chamber and / or station pressures, chamber and / or station temperatures, wafer temperatures, target power levels, RF power levels, substrate pedestal, chuck and / or susceptor positions, and other parameters of a particular process performed by the process tool 600. The system control software 658 may be configured in any suitable manner. For example, various process tool component subroutines or control objects may be written to control the operation of the process tool components used to perform the various process tool processes. The system control software 658 may be coded in any suitable computer readable programming language.

[0101] In some embodiments, the system control software 658 may include input / output control (IOC) sequence instructions for controlling the various parameters mentioned above. In some embodiments, other computer software and / or programs stored on the mass storage device 654 and / or memory device 656 associated with the system controller 650 may be used. Examples of programs or sections of programs for this purpose include a substrate positioning program, a process gas control program, a pressure control program, a heater control program, and a plasma control program.

[0102] The substrate positioning program may include program code for process tool components used to load the substrate onto the pedestal 618 and control the spacing between the substrate and other parts of the process tool 600.

[0103] The process gas control program may include code for controlling gas composition (e.g., any precursor, etching gas, or other process gas) and flow rates to stabilize the pressure of the process station, and optionally, code for flowing gases to one or more process stations prior to deposition. The pressure control program may include code for controlling the pressure of the process station, for example, by adjusting a throttle valve in the exhaust system of the process station, gas flow to the process station, etc.

[0104] The heater control program may include code for controlling the current to a heating unit used to heat the substrate, or the heater control program may control the delivery of a heat transfer gas (such as helium) to the substrate.

[0105] The plasma control program can include code for setting RF power levels applied to process electrodes in one or more process stations in accordance with embodiments herein.

[0106] The pressure control program can include code for maintaining pressure in the reaction chamber according to embodiments herein.

[0107] In some embodiments, there may be a user interface associated with the system controller 650. The user interface may include a display screen, a graphical software display of equipment and / or process conditions, and user input devices such as a pointing device, keyboard, touch screen, microphone, etc.

[0108] In some embodiments, the parameters adjusted by the system controller 650 may relate to process conditions. Non-limiting examples include process gas composition and flow rates, temperature, pressure, plasma conditions (such as RF bias power level, frequency, and exposure time), etc. These parameters may be provided to a user in the form of a recipe and may be entered utilizing a user interface.

[0109] Signals for monitoring the process may be provided by analog and / or digital input connections of the system controller 650 from various process tool sensors. Signals for controlling the process can be output at analog and digital output connections of the process tool 600. Non-limiting examples of process tool sensors that can be monitored include mass flow controllers, pressure sensors (such as pressure gauges), thermocouples, etc. Appropriately programmed feedback and control algorithms can be used with data from these sensors to maintain process conditions.

[0110] The system controller 650 can provide program instructions for carrying out the deposition processes described above. The program instructions can control various process parameters such as direct current (DC) power levels, RF bias power levels, pressure, temperature, etc. The instructions can control the parameters that operate the photoresist underlayer deposition process according to various embodiments described herein.

[0111] The system controller 650 typically includes one or more memory devices and one or more processors configured to execute instructions such that the apparatus performs methods according to the disclosed embodiments. Machine-readable media containing instructions for controlling process operations according to the disclosed embodiments may be coupled to the system controller 650.

[0112] In some implementations, the system controller 650 is part of a system, such a system may be part of the examples described above. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more processing platforms, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling system operations before, during, and after processing of a semiconductor wafer or substrate. Such electronics may be referred to as a "controller" and may control various components or subparts of one or more systems. The system controller 650 may be programmed to control any of the processes disclosed herein depending on the processing conditions and / or type of system. Such processes may include delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and motion settings, wafer loading and unloading to and from tools and other transfer tools connected or interlocked with the particular system, and / or wafer loading and unloading to and from load locks.

[0113] Broadly, the system controller 650 may be defined as electronic equipment having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, i.e., microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions communicated to the system controller 650 in the form of various individual settings (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. The operational parameters may, in some embodiments, be part of a recipe defined by a process engineer to accomplish one or more processing steps in the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0114] The system controller 650 may, in some embodiments, be part of, or coupled to, a computer that is integrated or coupled with the system or otherwise networked to the system, or a combination thereof. For example, the system controller 650 may be in the "cloud" or all or part of a fab host computer system. This allows for remote access of wafer processing. The computer may allow remote access to the system to monitor the current progress of a fabrication operation, review the history of past fabrication operations, review trends or performance criteria from multiple fabrication operations, modify parameters of a current process, set processing steps following a current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system over a network. Such a network may include a local network or the Internet. The remote computer may include a user interface that allows entry or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the system controller 650 receives instructions in the form of data. Such data identifies parameters for each processing step performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool that the system controller 650 is configured to interface with or control. Thus, as described above, the system controller 650 may be distributed, for example, by including one or more individual controllers that are networked together and cooperate toward a common purpose (such as the processes and controls described herein).An example of a distributed controller for such purposes would include one or more integrated circuits on the chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) and coupled to control the process in the chamber.

[0115] Exemplary systems may include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an ALD chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a tracking chamber or module, an EUV lithography chamber (scanner) or module, a dry development chamber or module, and any other semiconductor processing system that may be associated with or used in the fabrication and / or manufacturing of semiconductor wafers.

[0116] As described above, depending on the process step or steps being performed by the tool, the system controller 650 may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to and from tool locations and / or load ports in a semiconductor manufacturing factory.

[0117] In a particular embodiment, an inductively coupled plasma (ICP) reactor is described herein that may be suitable for etching operations suitable for practicing some embodiments. Although an ICP reactor is described herein, it should be understood that in some embodiments, a capacitively coupled plasma reactor may also be used.

[0118] 7 illustrates a schematic cross-sectional view of an inductively coupled plasma apparatus 700 suitable for performing certain embodiments or aspects of embodiments such as gas phase (dry) deposition, dry development, and / or etching. In other embodiments, other tools or tool types having the functionality to perform the dry deposition, development, and / or etching processes described herein may be used.

[0119] The inductively coupled plasma apparatus 700 includes an overall process chamber 724 structurally defined by a chamber wall 701 and a window 711. The chamber wall 701 can be fabricated from stainless steel or aluminum. The window 711 can be fabricated from quartz or other dielectric materials. An optional internal plasma grid 750 divides the overall process chamber into an upper sub-chamber 702 and a lower sub-chamber 703. In many embodiments, the plasma grid 750 can be removed, thereby utilizing the chamber space consisting of the sub-chambers 702 and 703. A chuck 717 is positioned within the lower sub-chamber 703 near the bottom inner surface. The chuck 717 is configured to receive and hold a semiconductor wafer 719 on which the etching and deposition processes are performed. The chuck 717, if present, can be an electrostatic chuck for supporting the wafer 719. In some embodiments, an edge ring (not shown) surrounds the chuck 717 and, if present on the chuck 717, has an upper surface that is approximately planar with an upper surface of the wafer 719. The chuck 717 also includes an electrostatic electrode for chucking and dechucking the wafer 719. For this purpose, a filter and DC clamp power supply (not shown) may be provided. Other control systems for lifting the wafer 719 from the chuck 717 may also be provided. The chuck 717 may be charged using an RF power supply 723. The RF power supply 723 is connected to a matching circuit 721 through a connection 727. The matching circuit 721 is connected to the chuck 717 through a connection 725. In this manner, the RF power supply 723 is connected to the chuck 717. In various embodiments, the bias power of the electrostatic chuck may be set to about 50V or may be set to a different bias power depending on the process to be performed according to the disclosed embodiments. For example, the bias power may be about 20V to about 100V, or about 30V to about 150V.

[0120] The elements for plasma generation include a coil 733 positioned over the window 711. In some embodiments, a coil is not used in the disclosed embodiments. The coil 733 is fabricated from a conductive material and includes at least one complete turn. The exemplary coil 733 shown in FIG. 7 includes three turns. A cross section of the coil 733 is shown symbolically, with the coil having an "X" rotating into the page and the coil having a "●" rotating out of the page. The elements for plasma generation also include an RF power source 741 configured to provide RF power to the coil 733. Generally, the RF power source 741 is connected to a matching circuit 739 through connection 745. The matching circuit 739 is connected to the coil 733 through connection 743. In this manner, the RF power source 741 is connected to the coil 733. An optional Faraday shield 749a is positioned between the coil 733 and the window 711. The Faraday shield 749a may be maintained in a spaced apart relationship relative to the coil 733. In some embodiments, the Faraday shield 749a is disposed directly above the window 711. In some embodiments, the Faraday shield 749b is between the window 711 and the chuck 717. In some embodiments, the Faraday shield 749b is not maintained in a spaced apart relationship to the coil 733. For example, the Faraday shield 749b may be directly below the window 711 without a gap. The coil 733, the Faraday shield 749a, and the window 711 are each configured to be substantially parallel to one another. The Faraday shield 749a may prevent metals or other species from depositing on the window 711 of the process chamber 724.

[0121] Process gases can flow into the process chamber via one or more main gas inlets 760 and / or one or more side gas inlets 770 positioned in the upper subchamber 702. Similarly, although not explicitly shown, similar gas inlets can be used to supply process gases to the capacitively coupled plasma processing chamber. A vacuum pump, e.g., a one or two stage mechanical dry pump and / or turbomolecular pump 740, can be used to draw process gases from the process chamber 724 and maintain pressure within the process chamber 724. For example, the vacuum pump can be used to evacuate the lower subchamber 703 during an ALD purge operation. A valve controlled conduit can be used to fluidly connect the vacuum pump to the process chamber 724 to selectively control application of the vacuum environment provided by the vacuum pump. This can be done with a closed loop controlled flow restriction device, such as a throttle valve (not shown) or a pendulum valve (not shown), during plasma processing operations. Similarly, a vacuum pump and a valve controlled fluid connection to the capacitively coupled plasma processing chamber can also be used.

[0122] During operation of the apparatus 700, one or more process gases may be supplied through the gas inlets 760 and / or 770. In certain embodiments, the process gases may be supplied only through the main gas inlet 760 or only through the side gas inlet 770. In some cases, the gas inlets shown in the figure may be replaced with more complex gas inlets, such as one or more showerheads. The Faraday shield 749a and / or the optional grid 750 may include internal channels and holes that allow delivery of process gases to the process chamber 724. Either or both of the Faraday shield 749a and the optional grid 750 may act as a showerhead for delivering process gases. In some embodiments, a liquid vaporization and delivery system may be located upstream of the process chamber 724, whereby once the liquid reactants or precursors are vaporized, the vaporized reactants or precursors are introduced into the process chamber 724 via the gas inlets 760 and / or 770.

[0123] Radio frequency power is supplied from an RF power supply 741 to the coil 733, causing an RF current to flow through the coil 733. The RF current flowing through the coil 733 generates an electromagnetic field around the coil 733. The electromagnetic field generates an induced current in the upper subchamber 702. Physical and chemical interactions of the various generated ions and radicals with the wafer 719 etch features of the wafer 719 and selectively deposit layers on the wafer 719.

[0124] When a plasma grid 750 is used such that both an upper subchamber 702 and a lower subchamber 703 are present, induced currents act on the gas present in the upper subchamber 702, generating an electron-ion plasma in the upper subchamber 702. The optional internal plasma grid 750 limits the number of thermal electrons in the lower subchamber 703. In some embodiments, the apparatus 700 is designed and operated such that the plasma present in the lower subchamber 703 is an ion-ion plasma.

[0125] Both the upper electron-ion plasma and the lower ion-ion plasma can contain positive and negative ions, but the ion-ion plasma has a greater ratio of negative ions to positive ions. Volatile etch and / or deposition byproducts can be removed from the lower subchamber 703 through port 722. The chuck 717 disclosed herein can operate at elevated temperatures ranging from about 10° C. to about 250° C. The temperature depends on the process operation and the particular recipe.

[0126] The apparatus 700 may be coupled to equipment (not shown) when installed in a clean room or fabrication facility. The equipment includes plumbing to provide process gases, vacuum, temperature control, and environmental particle control. These equipment will be coupled to the apparatus 700 when installed in the intended fabrication facility. Additionally, the apparatus 700 may be coupled to a transfer chamber that allows a robot to move semiconductor wafers in and out of the apparatus 700 using typical automated operations.

[0127] In some embodiments, a system controller 730 (which may include one or more physical or logical controllers) controls some or all of the operation of the process chamber 724. The system controller 730 may include one or more memory devices and one or more processors. In some embodiments, the apparatus 700 includes a switching system for controlling flow rates and durations when the disclosed embodiments are implemented. In some embodiments, the apparatus 700 may have a switching time of up to about 500 ms, or up to about 750 ms. The switching time may depend on the flowing chemistry, the selected recipe, the reactor architecture, and other factors.

[0128] In some implementations, the system controller 730 is part of a system, such a system may be part of the examples described above. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more processing platforms, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling system operations before, during, and after processing of a semiconductor wafer or substrate. Such electronics may be integrated into the system controller 730 and control various components or subcomponents of the system or systems. The system controller may be programmed to control any of the processes disclosed herein depending on the processing parameters and / or type of system. Such processes may include delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and motion settings, wafer loading and unloading to and from tools and other transfer tools connected or interlocked with the particular system, and / or wafer loading and unloading to and from load locks.

[0129] Broadly, the system controller 730 may be defined as electronic equipment having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, i.e., microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions communicated to the controller in the form of various individual settings (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. The operational parameters may, in some embodiments, be part of a recipe defined by a process engineer to accomplish one or more processing steps in the fabrication or removal of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0130] The system controller 730 may, in some embodiments, be part of, or coupled to, a computer that is integrated or coupled with the system or otherwise networked to the system, or a combination thereof. For example, the controller may be in the "cloud" or all or part of a fab host computer system. This allows for remote access of wafer processing. The computer may allow remote access to the system to monitor the current progress of a fabrication operation, review the history of past fabrication operations, review trends or performance criteria from multiple fabrication operations, modify parameters of a current process, set processing steps following a current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network. Such a network may include a local network or the Internet. The remote computer may include a user interface that allows entry or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the system controller 730 receives instructions in the form of data. Such data identifies parameters for each processing step performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the system controller 730 may be distributed, for example, by including one or more individual controllers that are networked together and cooperate toward a common purpose (such as the processes and controls described herein).An example of a distributed controller for such purposes would include one or more integrated circuits on the chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) and coupled to control the process in the chamber.

[0131] Exemplary systems may include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (e.g., PECVD) chamber or module, an ALD chamber or module, an ALE chamber or module, an ion implantation chamber or module, a tracking chamber or module, an EUV lithography chamber (scanner) or module, a dry development chamber or module, and any other semiconductor processing system that may be associated with or used in the fabrication and / or manufacturing of semiconductor wafers.

[0132] As described above, depending on the process step or steps being performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to and from tool locations and / or load ports within a semiconductor manufacturing factory.

[0133] EUVL patterning can be performed using any suitable tool, often referred to as a scanner, such as the TWINSCAN NXE:3300B® platform supplied by ASML, Veldhoven, The Netherlands). The EUVL patterning tool may be a standalone device from which substrates are loaded and unloaded for deposition and etching as described herein. Or, as described below, the EUVL patterning tool may be a module on a larger multi-component tool. FIG. 8 illustrates a semiconductor process cluster tool architecture 800 having a vacuum integrated deposition, EUV patterning, and dry develop / etch module interfaced with a vacuum transfer module suitable for carrying out the processes described herein. The processes can be performed without such vacuum integrated equipment, although such equipment may be advantageous in some embodiments.

[0134] FIG. 8 illustrates a semiconductor process cluster tool architecture having a vacuum integrated deposition and patterning module interfaced with a vacuum transfer module suitable for carrying out the processes described herein. The arrangement of transfer modules to "transfer" wafers between multiple storage facilities and processing modules is sometimes referred to as a "cluster tool architecture" system. The deposition and patterning modules are vacuum integrated according to the requirements of a particular process. Other modules, such as for etching, can also be included in the cluster.

[0135] A vacuum transfer module (VTM) 838 interfaces with four processing modules 820a-820d, which can be individually optimized to perform various fabrication processes. By way of example, the processing modules 820a-820d can be implemented to perform deposition, lithography operations, evaporation, ELD, dry develop, etch, strip, and / or other semiconductor processes. For example, module 820a may be a deposition reactor operable to deposit one or more of the layers shown in FIG. 2A; and module 820b deposition tool operable to deposit another layer shown in FIG. 2A other than the layer deposited by module 820a. Any number of deposition modules or other modules may be provided. Module 820c may be operable to perform one or more photolithography related operations, such as exposure, baking, and development operations. Module 820d may be operable to perform etching, for example to transfer a pattern from a radiation sensitive imaging layer to an underlying layer. It should be understood that the figures are not necessarily drawn to scale.

[0136] Airlocks 842 and 846, also known as loadlocks or transfer modules, interface with the VTM 838 and the patterning module 840. For example, as mentioned above, a suitable patterning module could be a TWINSCAN NXE:3300B® platform supplied by ASML, Veldhoven, The Netherlands). This tool architecture allows workpieces such as semiconductor substrates or wafers to be transferred under vacuum so that they do not react before exposure. The integration of the deposition module with the lithography tool is facilitated by the fact that EUVL also requires a significantly reduced pressure, given the strong optical absorption of incident photons by ambient gases such as H2O, O2, etc.

[0137] As mentioned above, this integrated architecture is only one possible embodiment of a tool for carrying out the described process. The process can also be carried out with a more conventional standalone EUVL scanner, and as a module, for example, with a deposition reactor that is standalone or integrated in a cluster architecture with other tools such as etch, strip, etc., without an integrated patterning module, as described with reference to FIG.

[0138] Airlock 842 may be an "out" load lock, referring to the transfer of substrates from the VTM 838 servicing deposition module 820a to the patterning module 840, and airlock 846 may be an "in" load lock, referring to the transfer of substrates from the patterning module 840 back to the VTM 838. The in load lock 846 may also provide an interface to the outside of the tool for access and egress of substrates. Each process module has a facet that interfaces the module to the VTM 838. For example, deposition process module 820a has facet 836. Within each facet, sensors, such as sensors 1-18 shown, are used to detect the passage of wafer 826 as it moves between the respective stations. Patterning module 840 and airlocks 842 and 846 may similarly include additional facets and sensors not shown.

[0139] The main VTM robot 822 transfers wafers 826 between modules including airlocks 842 and 846. In one embodiment, the robot 822 has one arm, and in another embodiment, the robot 822 has two arms, each arm having an end effector 824 that lifts a wafer such as wafer 826 for transfer. A front-end robot 844 is used therein to transfer wafers 826 from the exit airlock 842 to the patterning module 840 and from the patterning module 840 to the entry airlock 846. The front-end robot 844 can also transfer wafers 826 between the entry loadlock and the exterior of the tool for substrate access and egress. Because the entry airlock module 846 has the ability to adapt the environment between atmospheric pressure and vacuum, the wafers 826 can move between the two pressure environments without being damaged.

[0140] It should be noted that EUVL tools typically operate at a higher vacuum than deposition tools. In this case, it is desirable to increase the vacuum environment of the substrate during transfer between the deposition and EUVL tools to allow for outgassing of the substrate before entering the patterning tool. The unloading airlock 842 can provide this function by holding the transferred wafer at a low pressure, no higher than the pressure in the patterning module 840 for a period of time, and venting the off-gassing, so that the optics of the patterning tool 840 are not contaminated by off-gassing from the substrate. A suitable pressure for the venting off-gas airlock is 1E-8 Torr or less.

[0141] In some embodiments, a system controller 850 (which may include one or more physical or logical controllers) controls some or all of the operations of the cluster tool and / or its separate modules. Note that the controller may be local to the cluster architecture, or may be located outside the cluster architecture on the manufacturing floor, or may be located at a remote location and connected to the cluster architecture via a network. The system controller 850 may include one or more memory devices and one or more processors. The processor may include a central processing unit (CPU) or computer, analog and / or digital input / output connections, stepper motor controller boards, and other similar components. Instructions are executed on the processor to perform the appropriate control operations. These instructions may be stored in a memory device associated with the controller or provided over a network. In certain embodiments, the system controller executes system control software.

[0142] The system control software may include instructions for controlling the timing of application and / or magnitude of any aspect of tool or module operation. The system control software may be configured in any suitable manner. For example, various process tool component subroutines or control objects may be written to control the operation of process tool components necessary to perform various process tool processes. The system control software may be coded in any suitable computer readable programming language. In some embodiments, the system control software includes input / output control (IOC) sequence instructions for controlling the various parameters described above. For example, each stage of a semiconductor fabrication process may include one or more instructions executed by the system controller. For example, instructions for setting process conditions for condensation, deposition, evaporation, patterning, and / or etching stages may be included in the corresponding recipe stages.

[0143] In various embodiments, an apparatus for forming a negative and / or positive tone pattern mask is provided. The apparatus can include a process chamber for patterning, deposition, and etching, and a controller including instructions for forming the pattern mask. The instructions can include code for patterning features in a radiation-sensitive imaging layer on a semiconductor substrate by EUV exposure in the process chamber to expose a surface of the substrate, code for dry developing the photopatterned resist, and code for etching an underlying layer or layer stack using the patterned resist as a mask.

[0144] It should be noted that the computer controlling the movement of the wafers may be local to the cluster architecture, or may be located outside the cluster architecture on the manufacturing floor, or may be located at a remote location and connected to the cluster architecture via a network. The controller described above with respect to any of Figures 5, 6, or 7 may be implemented using the tool of Figure 8.

[0145] 9 illustrates an example of a deposition chamber (e.g., for vapor-based deposition of imaging layers and / or underlayers, etc.). As can be seen, the apparatus 900 includes a process chamber 902 having a lid 908 and a wafer transfer passage 904 sized to allow a substrate 922 to pass through and be placed on a wafer support 924. The wafer transfer passage 904 may have a gate valve 906 or similar door mechanism operable to seal or open the wafer transfer passage. For example, the process chamber 902 may be provided with a substrate 922 via a wafer handling robot located in an adjacent transfer chamber.

[0146] The wafer support 924 may include an ESC 926 that provides a wafer support surface for the substrate 922. The ESC 926 may include a base plate 934 bonded to an upper surface of a top plate 928. In the illustrated example, the top plate 928 has two separate electrical systems embedded therein. One such system is an electrostatic clamping electrode system having one or more clamping electrodes 932 that create an electric charge in the substrate 922, causing the substrate 922 to be attracted against the wafer support surface of the top plate 928.

[0147] Another system is a thermal control system that controls the temperature of the substrate 922 during processing conditions. In FIG. 9, the thermal control system features four annular resistive heater traces 930a, 930b, 930c, and 930d positioned under a clamping electrode 932. Each resistive heater trace 930a / b / c / d can be individually controlled to provide a different radial heating profile to the top plate 928 to maintain the substrate 922 with, for example, a temperature uniformity of ±0.5° C. in some cases. In other implementations, a single zone or a multi-zone heating system having more or less than four zones can be used. For example, in some implementations of the temperature control mechanism described above, a heat pump or Peltier junction may be used in place of the resistive heating traces.

[0148] The ESC 926 may also include a base plate 934 that provides structural support to the underside of the top plate 928 and may also act as a heat distribution system. For example, the base plate 934 may include one or more heat exchange passages 936 through which a heat exchange medium, e.g., water or an inert fluorinated liquid, may be circulated during use.

[0149] The ESC 926 may be supported by a wafer support housing 942 that is connected to and supported by a wafer support column 944. The wafer support column 944 may have other passages for wiring passages 948 for routing cabling (e.g., for supplying electrical power), fluid flow conduits (e.g., for carrying heat exchange media), and other equipment to the underside of the base plate 934 and / or top plate 928.

[0150] 9 also includes a substrate support Z actuator 946 that can provide movable support to the wafer support column 944. The wafer support Z actuator 946 can be actuated to move the wafer support column 944, and the wafer support 924 supported thereby, vertically up or down, for example, by up to several inches, within the reaction volume 920 of the processing chamber 902. In doing so, the gap distance X between the substrate 922 and the underside of the showerhead 910 can be adjusted in response to various process conditions.

[0151] The wafer support 924 may also include one or more edge rings that may be used to control and / or fine-tune various process conditions. In Figure 9, for example, an upper edge ring 938 is provided that sits above lower edge rings 940a and 940b, which are supported by a wafer support housing 942 and a third lower edge ring 940c.

[0152] The apparatus 900 may also include a system for removing process gases from the processing chamber 902 during and after processing. For example, the processing chamber 902 may include an annular plenum 956 that surrounds the wafer support column 944. The annular plenum 956 may in turn be fluidly connected to a vacuum foreline 952, which may be connected to a vacuum pump. A regulator valve 954 may be provided between the vacuum foreline 952 and the processing chamber 902 and may be actuated to control flow to the vacuum foreline 952. In some implementations, a baffle 950, e.g., an annular plate or other structure, may be provided that may serve to more evenly distribute the flow into the annular plenum 956 around the wafer support column 944, reducing the possibility of flow non-uniformities in the reactants flowing across the substrate 922.

[0153] The showerhead 910, as shown, is a dual plenum showerhead 910 and includes a first plenum 912 supplied with process gas via a first inlet 916 and a second plenum 914 supplied with process gas via a second inlet 918. Two or more plenums can be used to maintain separation between the precursors and the counter reactant prior to release of the precursors and the counter reactant. In some cases, a single plenum is used to deliver the precursors to the reaction space 920 of the processing chamber 902. Each plenum may have a corresponding set of gas distribution ports that fluidly connect the respective plenum with the reaction space 920 through a faceplate of the showerhead 910 (the faceplate is the portion of the showerhead 910 interposed between the bottom plenum and the reaction space 920).

[0154] The first inlet 916 and the second inlet 918 of the showerhead 910 can be supplied with process gases via a gas supply system, which can be configured to provide one or more precursors and / or counter reactants as described herein. A first valve manifold 968a can be configured to supply one or more precursors to the first inlet 916, while a second valve manifold 968b can be configured to supply other precursors or other reactants to the second inlet 918. In this example, the first valve manifold 968a includes, for example, multiple valves A1-A5. Valve A2 can be, for example, a three-way valve having one port fluidly connected to a first vaporizer 972a, another port fluidly connected to a bypass line 970a, and a third port fluidly connected to a port on another three-way valve A3. Similarly, valve A4 may be another three-way valve having one port fluidly connected to a second vaporizer 972b, another port fluidly connected to a bypass line 970a, and a third port fluidly connected to a port on another three-way valve A5. One of the other ports on valve A5 may be fluidly connected to the first inlet 916, and the remaining port on valve A5 may be fluidly connected to one of the remaining ports on valve A3. The remaining port on valve A3 may then be fluidly connected to valve A1, which may be fluidly interposed between valve A3 and a purge gas source 974, e.g., a source of nitrogen, argon, or other suitable inert gas (for precursors and / or back reactants). In some embodiments, only the first valve manifold is used.

[0155] For purposes of this disclosure, the term "fluidically connected" is used in reference to volumes, plenums, holes, etc. that may be connected to one another to form a fluid connection, similar to the way the term "electrically connected" is used in reference to components that are connected to one another to form an electrical connection. The term "fluidically interposed," when used, may be used to refer to a component, volume, plenum, or hole that is fluidly connected to at least two other components, volumes, plenums, or holes, such that fluid flowing from one of those other components, volumes, plenums, or holes to the other or another of those components, volumes, plenums, or holes will first flow through the "fluidically interposed" component before reaching the other or another of those components, volumes, plenums, or holes. For example, if a pump is fluidly interposed between a reservoir and an outlet, fluid flowing from the reservoir to the outlet will first flow through the pump before reaching the outlet.

[0156] The first valve manifold 968a can be controllable, such as by controlled actuation of valves A1-A5, to flow vapor from one or both of the vaporizers 972a and 972b to the process chamber 902 or through a first bypass line 970a to the vacuum foreline 952. The first valve manifold 968a can also be controllable to flow purge gas from a purge gas source 974 to the first inlet 916.

[0157] It will be appreciated that the second valve manifold 968b can be controlled in a similar manner, for example, by controlling valves B1-B5, to supply vapor from vaporizers 972c and 972d to the second inlet 918 or to the second bypass line 970b. It will be further appreciated that different manifold arrangements can be utilized as well, including a single integral manifold that includes valves for controlling the flow of precursors, counter reactants, and other reactants to the first inlet 916 and second inlet 918.

[0158] As previously mentioned, some devices 900 may feature a fewer number of vapor sources, e.g., only two vaporizers 972, in which case the valve manifold 968 may be modified to have a fewer number of valves, e.g., only valves A1-A3.

[0159] As described above, an apparatus such as apparatus 900 that may be used to perform dry deposition of a film may be configured to maintain a particular temperature profile within a process chamber 902. In particular, such an apparatus 900 may be configured to maintain the substrate 922 at a lower temperature, e.g., at least 25° C. to 50° C. lower, than most of the equipment of the apparatus 902 that comes into direct contact with the precursors and / or counter reactants.

[0160] Various heating systems may be included in the apparatus 900 to provide temperature control. For example, the process chamber 902 may have a receptacle for receiving a cartridge heater 958, e.g., vertical holes may be drilled in the four corners of the housing of the chamber 902 to receive the cartridge heater 958. In some implementations, the showerhead 910 may be covered with a heater blanket 960 that may be used to apply heat across the entire exposed top surface of the showerhead 910 to keep the showerhead temperature high. It may also be beneficial to heat the various gas lines used to direct vaporized reactants from the vaporizer 972 to the showerhead 910. For example, resistive heater tape may be wrapped around such gas lines and used to heat them to a high temperature. Any of the gas lines in FIG. 9, as well as the fate valve 906, may be actively or indirectly heated.

[0161] The various operating systems of the apparatus 900 can be controlled by a controller 984, which can include one or more processors 986 and one or more memory devices 988 operatively connected to each other and communicatively connected to the various systems and subsystems of the apparatus 901 to provide control functionality for these systems. For example, the controller 984 can be configured to control valves A1-A5 and B1-B5, the various heaters 958, 960, the vaporizer 972, the regulator valve 954, the gate valve 906, the wafer support Z actuator, etc.

[0162] Another feature that the apparatus 900 may include is shown in FIG. 10, which illustrates an enlarged side cross-sectional view and plan view of a portion of the substrate 922, top plate 928, and upper edge ring 938 of FIG. 9. As can be seen, in some implementations, the substrate 922 may be elevated from the majority of the top plate 928 by a number of small mesas 976, which may be shallow bosses that protrude a small distance from the nominal top surface of the top plate 928 to provide a backside gap 978 between the lower surface of the substrate 922 and the majority of the top plate 928. A peripheral wall feature 977 may be provided around the periphery of the top plate 928. The peripheral wall feature 977 may extend around the entire periphery of the top plate 928 and be nominally the same height as the mesas 976. During processing operations, a generally inert gas, such as helium, may flow into the backside gap 978 via one or more gas ports 982. This gas may then flow radially outward before encountering the peripheral wall feature 977, which restricts such radially outward flow and traps a high pressure region of gas between the substrate 922 and the top plate 928. Inert gas that leaks beyond the peripheral wall 977 may eventually escape through a radial gap 980 between the outer edge of the substrate 922 and a portion of the top edge ring 938. Such gas may act to protect the underside of the substrate from undesirable effects of the processing operations being performed by acting to prevent gases emitted by the showerhead 910 from reaching the underside of the substrate 922. At the same time, the gas emitted in the region of the back gap 978 may also act to increase thermal coupling between the substrate 922 and the top plate 928, thereby allowing the top plate 928 to more effectively heat or cool the substrate 922. Due to the high pressure provided by the peripheral wall, the gas in the region of the back gap 978 may be denser than the gas in the remainder of the chamber, thus providing a more effective thermal coupling between the substrate 922 and the top plate 928.

[0163] The controller 984 can be configured, for example, through the execution of computer-executable instructions, to cause the apparatus 900 to perform various operations consistent with the above disclosure.

[0164] Once the imaging layer and / or underlayer are deposited on the substrate 922, the substrate 922 may be transferred to one or more subsequent processing chambers or tools for additional operations (e.g., any described herein), as described above. Additional deposition apparatus are described in International Patent Application No. PCT / US2020 / 038968, filed June 22, 2020, entitled "APPARATUS FOR PHOTORESIST DRY DEPOSITION," the disclosure of which is incorporated herein by reference in its entirety.

[0165] experiment 11 illustrates experimental results showing the effectiveness of a diffusion barrier layer in reducing the diffusion of unstable species at different temperatures. In this experiment, the unstable species was hydrogen. Three substrates were tested, each having one of the structures shown in FIGS. 12A-12C.

[0166] As shown in Figure 12A, the first substrate 1200a included a layer 1204 of low temperature thermally deposited silicon nitride on a silicon substrate 1201. Low temperature thermally deposited silicon nitride is known to contain significant amounts of hydrogen that can act as an unstable species. The results for the first substrate 1200a are shown by line 1101 in Figure 11.

[0167] As shown in FIG. 12B, the second substrate 1200b included a silicon substrate 1201 and a layer 1204 of low-temperature thermally deposited silicon nitride capped with a diffusion barrier layer 1203 made of nitrogen-doped silicon carbide. The results for the second substrate 1200b are shown by line 1102 in FIG. 11. Although FIG. 12B shows the nitrogen-doped silicon carbide diffusion barrier layer 1203 positioned on top of the low-temperature thermally deposited silicon nitride layer 1204, it should be understood that this is for experimental and diffusion evaluation purposes only. In various photolithographic embodiments described herein, such as those described in connection with FIG. 2A, for example, the layers are switched such that the diffusion barrier layer 203 is positioned below the layer from which the unstable species originates (e.g., the underlayer 204).

[0168] As shown in Figure 12C, the third substrate 1200c included a layer of nitrogen-doped silicon carbide 1203 on a silicon substrate 1201. The results for the third substrate 1200c are shown by line 1103 in Figure 11. In general, the silicon nitride layers 1204 of the first and second substrates 1200a and 1200b were similar, and the nitrogen-doped silicon carbide layers 1203 of the second and third substrates 1200b and 1200c were similar. The silicon nitride layer 1204 had a thickness of about 100 nm, and the nitrogen-doped silicon carbide layer 1203 had a thickness of about 250 Å.

[0169] Substrates 1200a-1200c were heated at different temperatures and the signal corresponding to the amount of hydrogen in the exposed layer was measured. Figure 11 shows different temperatures along the x-axis and signal intensity along the y-axis. Generally, a higher signal intensity along the y-axis corresponds to a higher amount of hydrogen in the exposed layer on the substrate.

[0170] The data in Figure 11 can be used to calculate how effective a diffusion barrier layer (e.g., nitrogen-doped silicon carbide layer 1203 in this example) is in blocking diffusion of an unstable species (e.g., hydrogen in this example) from a first layer (e.g., silicon nitride layer 1204 in this example) through the diffusion barrier layer at a particular temperature. Equation 1 below provides an exemplary calculation:

number

[0171] In Equation 1, H blocking is expressed as a percentage and can be calculated for each temperature tested. Figure 11 shows a, b, and c labeled at different temperatures, but this is for illustrative purposes only. blocking When is calculated, the signal strength is taken into account at a specific temperature. Furthermore, Eq. blocking Although explicitly related to, it should be understood that this same technique can be used to assess the diffusion of other labile species as well.

[0172] In a related experiment, a series of potential diffusion barrier layers, such as those described in connection with FIG. 11, were tested, and the H blocking The degree of diffusion barrier was calculated at different temperatures. The thickness of the diffusion barrier layer ranged from about 50 to 250 Å. Among the different types of diffusion barrier layers tested, the best H blocking Those that showed performance were aluminum oxide and nitrogen-doped silicon carbide. Table 1 below shows the most promising results of this experiment, with results shown at both 450°C and 500°C. [Table 1]

[0173] These experiments show that a diffusion barrier layer can be very effective in reducing the diffusion of unstable species from a first layer to a second layer. As discussed above in connection with FIGS. 1A-1C and 2A-2C, particularly FIGS. 1C and 2C, reducing the diffusion of unstable species in one direction (e.g., downward from the underlayer to underlying layers such as the diffusion barrier layer, hardmask layer, etc.) results in relatively greater diffusion in the opposite direction (e.g., upward from the underlayer to overlying layers such as the radiation-sensitive imaging layer). This opposite / upward diffusion results in desired chemical changes, for example, within the radiation-sensitive imaging layer, as discussed in connection with FIGS. 3A and 3B. Thus, as shown in FIG. 2A, a diffusion barrier layer included between the underlayer and the hardmask can be used to maximize the diffusion of unstable species into the radiation-sensitive imaging layer, thereby maximizing the desired chemical changes that occur within the radiation-sensitive imaging layer as a result of this diffusion.

[0174] definition "Aliphatic" means a group consisting of at least 1 carbon atom and at least 50 carbon atoms (C 1-50 ), e.g., 1 to 25 carbon atoms (C 1-25 ), or 1 to 10 carbon atoms (C 1-10 ), including alkanes (or alkyls), alkenes (or alkenyls), alkynes (or alkynyls), including cyclic versions thereof, as well as straight-chain and branched-chain arrangements, and all stereoisomers and positional isomers. Such aliphatics can be unsubstituted or substituted with one or more groups, such as those described herein for alkyl groups.

[0175] "Alkenyl" refers to an optionally substituted C alkyl group having one or more double bonds. 2-24 An alkenyl group is a cyclic (e.g., C 3-24 The alkenyl group may be substituted or unsubstituted. For example, the alkenyl group may be substituted with one or more of the substituents described herein for alkyl.

[0176] "Alkoxy" refers to -OR, where R is an optionally substituted alkyl group as described herein. Exemplary alkoxy groups include methoxy, ethoxy, butoxy, trihaloalkoxy, such as trifluoromethoxy, and the like. An alkoxy group can be substituted or unsubstituted. For example, an alkoxy group can be substituted with one or more of the substituents described herein for alkyl. Exemplary unsubstituted alkoxy groups include C 1-3 , C 1-6 , C 1-12 , C 1-16 , C 1-18 , C 1-20 , or C 1-24 Examples of the alkyl group include alkoxy groups.

[0177] The terms "alkyl" and "alk" refer to a branched or unbranched saturated hydrocarbon group of 1 to 24 carbon atoms, such as methyl (Me), ethyl (Et), n-propyl (n-Pr), isopropyl (i-Pr), cyclopropyl, n-butyl (n-Bu), isobutyl (i-Bu), s-butyl (s-Bu), t-butyl (t-Bu), cyclobutyl, n-pentyl, isopentyl, s-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, eicosyl, tetracosyl, and the like. An alkyl group can be cyclic (e.g., C 3-24 The alkyl group can be branched or unbranched. The alkyl group can also be substituted or unsubstituted. For example, the alkyl group can include a haloalkyl, where the alkyl group is substituted with one or more halo groups as described herein. In another example, the alkyl group can be substituted with 1, 2, 3, or, in the case of an alkyl group of 2 or more carbons, 4 substituents independently selected from the group consisting of: (1) C 1-6 Alkoxy (e.g., -O-Ak, where Ak is an optionally substituted C 1-6 (2) amino (e.g., -NR N1 R N2 , R N1 and RN2 Each of is independently H or optionally substituted alkyl, or R N1 and R N2 each taken together with the nitrogen atom to which it is attached forms a heterocyclyl group), (3) aryl, (4) arylalkoxy (e.g., -O-Lk-Ar, where Lk is a divalent form of an optionally substituted alkyl and Ar is an optionally substituted aryl), (5) aryloyl (e.g., -C(O)-Ar, where Ar is an optionally substituted aryl), (6) cyano (e.g., -CN), (7) carboxaldehyde (e.g., -C(O)H), (8) carboxyl (e.g., -COH), (9) C 3-8 Cycloalkyl (e.g., monovalent saturated or unsaturated non-aromatic cyclic C 3-8 (10) halo (e.g., F, Cl, Br, or I), (11) heterocyclyl (e.g., a 5-, 6-, or 7-membered ring containing 1, 2, 3, or 4 non-carbon heteroatoms such as nitrogen, oxygen, phosphorus, sulfur, or halo, unless otherwise specified), (12) heterocyclyloxy (e.g., -O-Het, where Het is a heterocyclyl as described herein), (13) heterocyclyloyl (e.g., -C(O)-Het, where Het is a heterocyclyl as described herein), (14) hydroxyl (e.g., -OH), (15) N-protected amino, (16) nitro (e.g., -NO), (17) oxo (e.g., =O), (18) -COR A , R A (a)C 1-6 Alkyl, (b) C 4-18 aryl, and (c) (C 4-18 Aryl)C 1-6 (19) -C(O)NR B R C , R B and R C each of which is independently (a) hydrogen, (b) C 1-6 Alkyl, (c) C 4-18 aryl, and (d) (C4-18 Aryl)C 1-6 alkyl (e.g., -Lk-Ar, where Lk is a divalent form of an optionally substituted alkyl group and Ar is an optionally substituted aryl), and (20) -NR G R H , R G and R H each of which is independently (a) hydrogen, (b) an N-protecting group, (c) C 1-6 Alkyl, (d) C 2-6 alkenyl (e.g., optionally substituted alkyl having one or more double bonds); 2-6 alkynyl (e.g., optionally substituted alkyl having one or more triple bonds); (f) C 4-18 Aryl, (g) (C 4-18 Aryl)C 1-6 alkyl (e.g., Lk-Ar, where Lk is a divalent form of an optionally substituted alkyl group and Ar is an optionally substituted aryl); (h) C 3-8 cycloalkyl, and (i) (C 3-8 Cycloalkyl)C 1-6 alkyl (e.g., -Lk-Cy, where Lk is a divalent form of an optionally substituted alkyl group and Cy is an optionally substituted cycloalkyl as described herein), and in one embodiment, there are no two groups attached to the nitrogen atom via a carbonyl group. The alkyl group can be a primary, secondary, or tertiary alkyl group substituted with one or more substituents (e.g., one or more halo or alkoxy). In some embodiments, the unsubstituted alkyl group is selected from the group consisting of C 1-3 , C 1-6 , C 1-12 , C 1-16 , C 1-18 , C 1-20 , or C 1-24 It is an alkyl group.

[0178] "Alkylene" refers to the polyvalent (e.g., divalent) form of an alkyl group as described herein. Exemplary alkylene groups include methylene, ethylene, propylene, butylene, and the like. In some embodiments, an alkylene group is a C 1-3 , C 1-6 , C 1-12 , C 1-16 , C 1-18 , C 1-20 , C 1-24 , C 2-3 , C 2-6 , C 2-12 , C 2-16 , C 2-18 , C 2-20 , or C 2-24 It is an alkylene group. The alkylene group can be branched or unbranched. The alkylene group can also be substituted or unsubstituted. For example, the alkylene group can be substituted with one or more of the substituents described herein for alkyl.

[0179] "Alkynyl" refers to an optionally substituted C alkyl group having one or more triple bonds. 2-24 It means an alkyl group. An alkynyl group can be cyclic or acyclic, and is exemplified by ethynyl, 1-propynyl, and the like. An alkynyl group can also be substituted or unsubstituted. For example, an alkynyl group can be substituted with one or more of the substituents described herein for alkyl.

[0180] "Amino" means -NR N1 R N2 means R N1 and R N2 is independently H, optionally substituted alkyl, or optionally substituted aryl, or R N1 and R N2 together with the nitrogen atom to which each is attached form a heterocyclyl group, as defined herein.

[0181] "Aromatic" means, unless otherwise specified, a cyclic conjugated group or moiety of 5-15 ring atoms having a single ring (e.g., phenyl) or multiple fused rings in which at least one ring is aromatic (e.g., naphthyl, indolyl, or pyrazolopyridinyl), i.e., at least one ring, and optionally multiple fused rings, have a continuous delocalized π-electron system. Typically, the number of out-of-plane π-electrons corresponds to Huckel's rule (4n+2). The point of attachment to the parent structure is typically through the aromatic portion of the fused ring system. Such aromatics can be unsubstituted or substituted with one or more groups, such as those described herein for alkyl or aryl groups. Still other substituents may include aliphatic, haloaliphatic, halo, nitrate, cyano, sulfonate, sulfonyl, and the like.

[0182] "Aryl" refers to fused benzo-C groups, such as, but not limited to, indanyl, tetrahydronaphthyl, and fluorenyl. 4-8 It refers to groups that contain any carbon-based aromatic group, including phenyl, benzyl, anthracenyl, anthryl, benzocyclobutenyl, benzocyclooctenyl, biphenylyl, chrysenyl, dihydroindenyl, fluoranthenyl, indacenyl, indenyl, naphthyl, phenanthryl, phenoxybenzyl, picenyl, pyrenyl, terphenyl, and the like, including cycloalkyl radicals (e.g., as defined herein). The term aryl also includes heteroaryl, which is defined as a group that contains an aromatic group with at least one heteroatom incorporated within the ring of the aromatic group. Examples of heteroatoms include, but are not limited to, nitrogen, oxygen, sulfur, and phosphorus. Similarly, the term non-heteroaryl, which is also included in the term aryl, defines a group that contains an aromatic group that does not contain a heteroatom. An aryl group can be substituted or unsubstituted. An aryl group can be substituted with 1, 2, 3, 4, or 5 substituents, such as those described herein for alkyl. In certain embodiments, an unsubstituted aryl group is a C 4-18 , C 4-14 , C 4-12 , C 4-10 , C 6-18 , C6-14 , C 6-12 , or C 6-10 It is an aryl group.

[0183] By "carbide" is meant a compound that contains at least one carbon atom and at least one other element.

[0184] "Carbonyl" refers to the group -C(O)-, which can also be depicted as >C=O, or -CO.

[0185] "Carboxyl" refers to the group -CO2H.

[0186] "Carboxaldehyde" refers to the group -C(O)H.

[0187] "Cyano" refers to the radical -CN.

[0188] "Cycloalkenyl" means, unless otherwise specified, a monovalent unsaturated non-aromatic or aromatic cyclic hydrocarbon group of 3 to 8 carbons having one or more double bonds. Cycloalkenyl groups can also be substituted or unsubstituted. For example, cycloalkenyl groups can be substituted with one or more groups, including those described herein for alkyl.

[0189] "Cycloalkyl," unless otherwise specified, means a monovalent saturated or unsaturated non-aromatic or aromatic cyclic hydrocarbon group of three to eight carbons, exemplified by cyclopropyl, cyclobutyl, cyclopentyl, cyclopentadienyl, cyclohexyl, cycloheptyl, bicyclo[2.2.1.]heptyl, and the like. Cycloalkyl groups can also be substituted or unsubstituted. For example, cycloalkyl groups can be substituted with one or more groups, including those described herein for alkyl.

[0190] "Diffusion barrier layer" means a layer of material positioned between an underlayer and a hardmask layer, where the material of the diffusion barrier layer reduces diffusion of unstable species from the underlayer into the hardmask layer.

[0191] "Dose" refers to the amount of radiation provided to a semiconductor substrate to induce chemical changes in a radiation sensitive layer during a photolithographic operation.

[0192] "Ester" as used herein means -OC(O)A 1 or -C(O)OA 1 means, A 1 can be an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, a cycloalkyl group, a cycloalkenyl group, a heterocycloalkyl group, or a heterocycloalkenyl group described herein.

[0193] "Halo" means F, Cl, Br, or I.

[0194] "Haloalkyl" means an alkyl group, as defined herein, that is substituted with one or more halo.

[0195] By "hard mask" it is meant a material that acts as a mask during an etching operation, as opposed to a soft mask material such as a conventional soft organic polymer resist.

[0196] "Heteroalkyl" means an alkyl group, as defined herein, that contains one, two, three, or four non-carbon heteroatoms (e.g., independently selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur, selenium, or halo).

[0197] "Heterocyclyl" means, unless otherwise specified, a 3-, 4-, 5-, 6-, or 7-membered ring (e.g., 5-, 6-, or 7-membered ring) containing 1, 2, 3, or 4 non-carbon heteroatoms (e.g., independently selected from the group consisting of nitrogen, oxygen, phosphorus, sulfur, selenium, or halo). The 3-membered ring has 0-1 double bonds, the 4- and 5-membered rings have 0-2 double bonds, and the 6- and 7-membered rings have 0-3 double bonds. The term "heterocyclyl" also includes bicyclic, tricyclic, and tetracyclic groups, in which any of the above heterocycles are fused to one, two, or three rings independently selected from the group consisting of an aryl ring, a cyclohexane ring, a cyclohexene ring, a cyclopentane ring, a cyclopentene ring, and another monocyclic heterocycle such as indolyl, quinolyl, isoquinolyl, tetrahydroquinolyl, benzofuryl, benzothienyl, and the like. Heterocyclyl groups can be substituted or unsubstituted, for example, with one or more of the substituents described herein for alkyl.

[0198] "Heterocyclyloxy" means a heterocyclyl group, as defined herein, attached to the parent molecular group through an oxygen atom.

[0199] "Heterocyclyloyl" means a heterocyclyl group, as defined herein, attached to the parent molecular group through a carbonyl group.

[0200] "Hydrocarbyl" means a univalent group formed by removing a hydrogen atom from a hydrocarbon. Non-limiting unsubstituted hydrocarbyl groups include alkyl, alkenyl, alkynyl, and aryl, as defined herein, which groups contain only carbon and hydrogen atoms. Hydrocarbyl groups can be substituted or unsubstituted. For example, hydrocarbyl groups can be substituted with one or more of the substituents described herein for alkyl. In other embodiments, any alkyl or aryl group herein can be replaced with a hydrocarbyl group, as defined herein. As used herein, "hydrocarbyl end" is used interchangeably with hydrocarbon end and refers to a group that is an aryl group having a hydrogen atom, such as (C x H y ) refers to a compound having the terminal formula:

[0201] "Homogeneous" means uniform. A homogeneous layer is uniform in composition. A homogeneous layer may be a single material or a uniform mixture of two or more materials. A homogeneous layer does not have a compositional gradient or a non-uniform combination of two or more materials.

[0202] "Hydroxyl" means --OH.

[0203] By "unstable species" is meant a species that has a high probability of migrating within a first material (e.g., the material from which the unstable species originates) or from a first material to a second material (e.g., from the material from which the unstable species originates to an adjacent material).

[0204] "Metal oxypolymer" means a polymer that contains both metal and oxygen atoms. The metal atoms may or may not be directly bonded to oxygen atoms.

[0205] By "negative-acting photoresist" is meant a photoresist in which the portions of the photoresist exposed to light are rendered insoluble to a photoresist developer or are selectively retained after exposure to radiation.

[0206] By "nitride" is meant a compound that contains at least one nitrogen atom and at least one other element.

[0207] "Nitro" refers to the -NO2 group.

[0208] "Heterogeneous" means not uniform. A heterogeneous layer has heterogeneity with respect to at least one property. A heterogeneous layer may include a heterogeneous mixture of two or more materials. A heterogeneous layer may also include a gradient with respect to one or more properties.

[0209] By "oxide" is meant a compound that contains at least one oxygen atom and at least one other element.

[0210] "Oxo" means the group ═O.

[0211] "Oxy" means --O--.

[0212] By "oxycarbide" is meant a compound that contains at least one oxygen atom and at least one carbon atom.

[0213] By "oxynitride" is meant a compound that contains at least one oxygen atom and at least one nitrogen atom.

[0214] "Patterned structure" means a partially fabricated semiconductor device intended for use in photolithography.

[0215] "Photocrosslinkable" means a material that crosslinks upon exposure to radiation.

[0216] "Photodegradable" means a material that generates hydrophilic products under radiation.

[0217] "Photopolymerizable" means a material that initiates polymerization upon exposure to radiation. Such materials typically generate free radicals upon exposure to radiation.

[0218] By "positive-acting photoresist" is meant a photoresist in which the portions of the photoresist exposed to radiation become soluble in a photoresist developer or are selectively removed after exposure to radiation.

[0219] "Radiation-sensitive imaging layer" means a layer of material that is susceptible to change when exposed to radiation, such as during a photolithographic operation.

[0220] "Radiolytic ligand" means an ion or molecule that is capable of binding to a central atom to form a complex and being cleaved from the central atom by application of radiation. As used herein, the terms radiolytic and radiocleavable are used interchangeably.

[0221] "Sulfonyl" means -S(O)A 1 means, A 1 can be a hydrogen group, an alkyl group, a halogenated alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, a cycloalkyl group, a cycloalkenyl group, a heterocycloalkyl group, or a heterocycloalkenyl group as described herein.

[0222] "Thio" refers to the group --S--.

[0223] "Thiol" refers to a -SH group.

[0224] "Underlayer" means a layer positioned between the radiation-sensitive imaging layer and the hardmask layer, which contains an unstable species as described herein.

[0225] As used herein, the term "about" means ±10% of the recited value. As used herein, the term modifies a recited value, a range of values, or one or more of the endpoints of a range.

[0226] As used herein, the terms "top," "bottom," "upper," "lower," "above," and "below" are used to provide relative relationships between structures. Use of these terms does not indicate or require that a particular structure must be located in a particular location within the apparatus.

[0227] conclusion Although the foregoing embodiments have been described in some detail for clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems, and apparatus of the present embodiments. Thus, the present embodiments should be considered as illustrative rather than restrictive, and the embodiments should not be limited to the details set forth herein.

Claims

1. 1. A patterning structure comprising: a substrate comprising a partially fabricated semiconductor device film stack; a radiation-sensitive imaging layer disposed over the substrate; an underlayer positioned below the radiation sensitive imaging layer, the underlayer comprising an unstable species; a hard mask layer positioned below the underlayer; a diffusion barrier layer positioned between the underlayer and the hardmask layer, the diffusion barrier layer comprising a diffusion barrier material that reduces diffusion of the unstable species from the underlayer to the hardmask layer; A patterning structure comprising:

2. 2. The patterning structure of claim 1, The patterned structure, wherein the diffusion barrier material comprises a material selected from the group consisting of an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof.

3. 3. The patterning structure of claim 2, The patterned structure, wherein the diffusion barrier layer comprises the oxide material, the oxide material being a material selected from the group consisting of a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

4. 3. The patterning structure of claim 2, The patterned structure, wherein the diffusion barrier material comprises the nitride material, the nitride material being a material selected from the group consisting of a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

5. 3. The patterning structure of claim 2, The patterned structure, wherein the diffusion barrier material comprises the carbide material, the carbide material being a material selected from the group consisting of a metal carbide, silicon carbide, a metal oxycarbide, silicon oxycarbide, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

6. 6. The patterning structure of claim 5, The patterned structure, wherein the diffusion barrier material comprises silicon carbide, the silicon carbide being doped with at least one of nitrogen and oxygen.

7. 2. The patterning structure of claim 1, The patterning structure, wherein the unstable species is hydrogen.

8. 2. The patterning structure of claim 1, The patterned structure wherein the radiation-sensitive imaging layer comprises a photoresist material, optionally wherein the photoresist material is a metal-containing photoresist material, optionally wherein the photoresist material is an organometallic-containing photoresist material.

9. 2. The patterning structure of claim 1, The patterned structure, wherein the underlayer comprises a hydrogen-containing carbon layer including at least one dopant, the at least one dopant being selected from the group consisting of oxygen, silicon, nitrogen, tungsten, boron, iodine, chlorine, or combinations thereof, and the diffusion barrier layer is deposited using a dry vapor-based deposition technique or using a wet liquid-based deposition technique.

10. 2. The patterning structure of claim 1, The patterned structure, wherein the diffusion barrier layer reduces diffusion of the unstable species from the underlying layer into the hard mask layer by at least about 60%, or at least about 90%.

11. 1. A method of making a patterning structure, comprising the steps of: providing a substrate having a hard mask layer thereon; depositing a diffusion barrier layer over the hard mask layer, the diffusion barrier layer comprising a diffusion barrier material; depositing an underlayer over the diffusion barrier layer, the underlayer including an unstable species; depositing a radiation-sensitive imaging layer over the underlayer; Including, the diffusion barrier layer reduces diffusion of the unstable species from the underlying layer into the hard mask layer; method.

12. 12. The method of claim 11, The method, wherein the diffusion barrier material comprises a material selected from the group consisting of an oxide material, a nitride material, a carbide material, silicon, a silicide material, a sulfide material, a metal-containing material, or a combination thereof.

13. 13. The method of claim 12, The method of claim 1, wherein the diffusion barrier layer comprises an oxide material selected from the group consisting of a metal oxide, a silicon oxide, a metal oxynitride, a silicon oxynitride, a metal oxycarbide, a silicon oxycarbide, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

14. 13. The method of claim 12, The method of claim 1, wherein the diffusion barrier material comprises a nitride material selected from the group consisting of a metal nitride, a silicon nitride, a metal oxynitride, a silicon oxynitride, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

15. 13. The method of claim 12, The method of claim 1, wherein the diffusion barrier material comprises a carbide material selected from the group consisting of a metal carbide, silicon carbide, a metal oxycarbide, silicon oxycarbide, or a combination thereof, and optionally the diffusion barrier material comprises a metal selected from the group consisting of aluminum, titanium, molybdenum, tungsten, tin, or a combination thereof.

16. 16. The method of claim 15, The method, wherein the diffusion barrier material comprises silicon carbide, the silicon carbide being doped with at least one of nitrogen and oxygen.

17. 12. The method of claim 11, The method according to claim 1, wherein the unstable species is hydrogen.

18. 12. The method of claim 11, The method wherein the radiation-sensitive imaging layer comprises a photoresist material, optionally wherein the photoresist material is a metal-containing photoresist material, optionally wherein the photoresist material is an organometallic-containing photoresist material.

19. 12. The method of claim 11, The method of claim 1, wherein the underlayer comprises a hydrogen-containing carbon layer including at least one dopant, the at least one dopant being selected from the group consisting of oxygen, silicon, nitrogen, tungsten, boron, iodine, chlorine, or combinations thereof, and the diffusion barrier layer is deposited using a dry vapor-based deposition technique or using a wet liquid-based deposition technique.

20. 12. The method of claim 11, The method of claim 1, wherein the diffusion barrier layer reduces diffusion of the unstable species from the underlying layer into the hard mask layer by at least about 60%, or at least about 90%.

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