Using ALE to etch a metal oxide substrate and selective deposition

Abstract

Methods and apparatuses for processing metal oxide films are provided. The method includes: (a) exposing the metal oxide film to a boron halide reactant and igniting a first plasma with a first bias power to modify the surface of the metal oxide film; and (b) exposing the modified surface of the metal oxide film to a second plasma at a second bias power for a time sufficient to remove the modified surface without sputtering. The method further includes (c) selectively depositing a metal oxide material on the metal oxide film to fill cracks within the metal oxide film.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Application No. 15 / 799,675, filed on October 31, 2017, entitled "ETCHING METAL OXIDE SUBSTRATES USING ALE AND SELECTIVE DEPOSITION", which is incorporated herein by reference in its entirety for all purposes. Background of the Invention

[0003] Patterning methods are crucial for semiconductor processing. Extreme ultraviolet (EUV) lithography techniques have been explored to extend lithography beyond its optical limits and replace current lithography methods for patterning small critical - dimension features. Current EUV lithography methods result in poor edge roughness and weak patterning that may ultimately render the substrate useless. Summary of the Invention

[0004] Methods and apparatuses for processing semiconductor substrates are provided herein. One aspect relates to a method of smoothing a metal - oxide film by combining atomic layer etching (ALE) and selective ALD. In a particular embodiment, the metal - oxide film is an EUV - patterned metal - oxide film on a carbon - based substrate, and the ALE and ALD are selective to the carbon - containing material of the substrate such that the patterned metal - oxide film can be smoothed without damaging the underlying substrate. The smoothed patterned metal - oxide film can then be used as a mask to etch the underlying carbon - based substrate, resulting in an improvement in the local critical dimension (LCD) of the features etched in the substrate.

[0005] In some embodiments, the method of processing a metal - oxide film comprises: (a) exposing the metal - oxide film to a boron - halide reactant and igniting a first plasma with a first bias power to modify the surface of the metal - oxide film; (b) exposing the modified surface of the metal - oxide film to a second plasma at a second bias power for a time sufficient to remove the modified surface without sputtering; and (c) selectively depositing a metal - oxide material on the metal - oxide film to fill cracks within the metal - oxide film. As a result, the metal - oxide film is smoothed. In a particular embodiment, (a) and (b) comprise atomic layer etching (ALE) processing, and (c) comprises atomic layer deposition (ALD) processing. Additionally, the ALE processing and / or the ALD processing can be selective to the carbon - containing material located beneath the metal - oxide film. Further, the metal - oxide film can be smoothed without damaging the carbon - containing material.

[0006] In some embodiments, the smoothed metal oxide film is used as a mask to etch a carbon-based substrate positioned beneath the metal oxide film, resulting in an improvement in the local critical dimension (LCD) of the features etched in the carbon-based substrate.

[0007] In some embodiments, the boron halide reactant is boron trichloride gas (BCl 3 ).

[0008] In some embodiments, the second plasma is generated by chlorine gas (Cl 2 ).

[0009] In some embodiments, the second plasma is generated by an argon-containing gas.

[0010] In some embodiments, the first plasma is generated using a plasma power between about 300 W and about 900 W. The first bias power can be 0 V and applied for about 5 seconds.

[0011] In some embodiments, the metal oxide film is a zirconia (ZrO 2 ) film.

[0012] In some embodiments, the metal oxide film is an alumina (Al 2 O 3 ) film. The modified surface of the alumina (Al 2 O 3 ) film can be exposed to the second plasma generated by an argon-containing gas.

[0013] In some embodiments, the metal oxide material is zirconia (ZrO 2 ). In some embodiments, the zirconia (ZrO 2 ) can be deposited by ALD using a thermal half-reaction of a zirconium precursor and an oxygen-containing precursor, the zirconium precursor selected from the group consisting of zirconium amide, zirconium halide, or zirconium alkoxide; and the oxygen-containing precursor selected from the group consisting of water, alcohol, ozone, or oxygen. A 1-second dosage of zirconium amide reacted with water provided at a partial pressure of 10 millitorr (mTorr) can be sufficient to achieve a saturation thickness of 1 angstrom per ALD cycle.

[0014] In some embodiments, the temperature at which deposition is carried out depends on the thermal stability of the zirconium source.

[0015] In some embodiments, the deposition of the zirconia (ZrO 2 ) by ALD is selective with respect to a carbon-containing material positioned beneath the metal oxide film, and further wherein the oxygen-containing precursor does not oxidize the carbon-containing material.

[0016] In some embodiments, the metal oxide material is alumina (Al 2 O 3 ), and the alumina (Al 2 O 3 ) can be deposited by ALD using thermal half-reactions of an aluminum precursor and an oxygen-containing precursor, where the aluminum precursor is selected from the group consisting of aluminum amides, aluminum halides, aluminum alkoxides, or aluminum alkyls; and the oxygen-containing precursor is selected from the group consisting of water, alcohols, ozone, or oxygen. In a particular embodiment, the aluminum alkyl is trimethylaluminum.

[0017] On the other hand, there is provided an apparatus for processing a substrate, the apparatus comprising: one or more processing chambers, each processing chamber including a chuck; one or more gas inlets leading to the processing chamber and associated flow control hardware; and a controller having at least one processor and a memory, wherein the at least one processor and the memory are communicatively coupled to each other, the at least one processor is at least operatively connected to the flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the flow control hardware by: exposing a metal oxide film to a boron halide reactant and igniting a first plasma with a first bias power to modify the surface of the metal oxide film; exposing the modified surface of the metal oxide film to a second plasma at a second bias power for a time sufficient to remove the modified surface without sputtering; and selectively depositing a metal oxide material on the metal oxide film to fill cracks in the metal oxide film.

[0018] These and other aspects are further described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of an example of atomic layer etching (ALE) of a film on a substrate.

[0020] Figure 2 is a schematic diagram of an example of ALE on a resist having protrusions.

[0021] Figure 3 is a schematic diagram of an example of a removal operation during ALE.

[0022] Figure 4 is a schematic diagram of a selective deposition cycle that can be used according to certain disclosed embodiments.

[0023] Figure 5 is a process flow diagram of operations performed according to the disclosed embodiments.

[0024] Figure 6 A process flow diagram of operations performed in accordance with the disclosed embodiments.

[0025] Figure 7 A schematic diagram of an exemplary processing chamber for performing certain disclosed embodiments.

[0026] Figure 8 A schematic diagram of an exemplary processing apparatus for performing certain disclosed embodiments. DETAILED DESCRIPTION

[0027] In the following description, numerous specific details are set forth 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 processing operations have not been described in detail to avoid unnecessarily obscuring the disclosed embodiments. Although the disclosed embodiments will be described in conjunction with specific embodiments, it should be understood that this is not intended to limit the disclosed embodiments.

[0028] The patterning of thin films in semiconductor processing is used in the fabrication and assembly of semiconductor devices. Conventional patterning involves lithography such as 193 nm lithography. In lithography, a pattern is printed onto a mask by emitting photons from a photon source and the pattern is printed onto a photosensitive photoresist (PR), thereby causing a chemical reaction in the PR that removes certain portions of the PR to form the pattern. As devices are scaled down, the need to print smaller features has also increased. Although various patterning techniques have been developed for use with conventional lithography, many patterning techniques use multiple layer deposition and etching processes. The scaling of features on advanced semiconductor integrated circuits (ICs) and other devices has driven lithography to improve resolution by moving to smaller imaging source wavelengths.

[0029] Extreme ultraviolet (EUV) lithography has been developed to print smaller patterns on PR using an EUV light source with a wavelength of approximately 13.5 nm in state-of-the-art lithography tools (also known as scanners). Although next-generation EUV was initially expected to support 45 nm technology node manufacturing in 2006, such development has long been postponed due to several productivity issues. Due to the inherent difficulties in generating and focusing 13.5 nm photons, one challenge in EUV productivity has been to generate sufficient power to perform patterning. The system throughput and thus the resulting total cost and productivity are determined by the ratio of the photons transmitted at the wafer to the photons required to image the PR. Although methods for modifying the source have been developed over the past decade, for the 45 nm technology node, the methods have not yet achieved a source power of 250 W to allow for the effective use of EUV technology. Due to shot noise and resist blur, the source power required to perform EUV increases as the device shrinks, such that at the 5 nm technology node, performing EUV at a source power of 500 W - 1000 W is cost-competitive compared to existing patterning technologies.

[0030] Insufficient source power can lead to a loss of pattern fidelity, both in terms of the edge roughness of the patterned image and the defined critical dimensions, especially for via imaging. Among other reasons, this is due to the few photons available for each via image, the random variation in the number of photons per feature, and the efficiency of each photon in generating photoacid, which can lead to random variation in the hole size (also known as local critical dimension uniformity, or as referred to herein "LCDU") and edge roughness (also known as line edge roughness, or as referred to herein "LER").

[0031] Current techniques for patterning PR for small critical dimension devices include reactive ion etching ("RIE") processes to harden, "smoothen" (e.g., reduce protrusion height and / or fill cracks), and remove residues from the PR. However, current RIE processes cannot address the LER or LCDU issues. For example, PR that has been processed by RIE may still have various unwanted accumulated materials, such as small stringers between features and resist located on or near the bottom of the features.

[0032] This unwanted roughness of the pattern can transfer into the substrate beneath the patterned PR. To address this roughness, explicit smoothing steps or additional processing steps can be applied to the PR, and these steps have proven to achieve the desired reduction in the surface roughness of the pattern. As advanced semiconductor manufacturing technologies move towards EUV lithography, with increased stochastic processing, increased radiochemistry, and increased use of new PR systems, such considerations must also be addressed, while meeting more stringent surface roughness targets at smaller feature sizes. Such requirements may benefit from the development of new methods for smoothing the roughness of patterned PR.

[0033] Certain roughness-related issues are often observed in organically chemically activated PR systems. Due to the diffusion of photoacids and the activated electrons in the PR pattern, the PR system may encounter photoresist "fuzziness". In EUV systems, this problem can be severe because the energy of the incident photons provided by EUV is too high to convert the photoacids they strike, so electrons must first be generated at a lower energy level through photon absorption in the PR (e.g., via radiochemistry). Common challenges include generating a sufficiently bright EUV radiation source, which can force the amplification of each generated electron in a cascade reaction, potentially leading to an additional loss of PR pattern fidelity.

[0034] In addition, as observed in organic PR systems, the cyclic deposition of carbon-based films with carbon-based atomic layer etching (ALE) self-limiting trimming processes has proven to reduce surface roughness and feature-to-feature variation due to, for example, photon stochasticity and resist fuzziness.

[0035] Potential improvement in photoresist fuzziness associated with EUV exposure can be achieved by using metal ligands. Under EUV exposure, this metal ligand can be directly converted into a metal oxide, skipping resist amplification and associated resist fuzziness. The metal oxide can then be used as a hard mark for patterning the underlying layer, which may contain carbon materials. By directly absorbing high-energy EUV photons, such a system can significantly improve the PR fuzziness that is inherent in organically chemically amplified systems.

[0036] However, due to the low power levels available in EUV, even metal-oxide-based mask materials can benefit from techniques for reducing surface roughness resulting from photon randomness and any residual blur in the metal-ligand to metal-oxide conversion. Applying the metal oxide via deposition (e.g., chemical vapor deposition (CVD) or atomic layer deposition (ALD)), followed by thermal or plasma-based atomic layer etching (ALE) of the metal oxide can together smooth the PR patterned with the metal oxide for reducing LER, LCDU improvement, and CD control. The process is generally cyclic, e.g., deposition followed by etching, and optionally repeating such processing. Thus, loading can be exploited in the deposition or etching step to reduce variation between features while maintaining the desired CD target with a corresponding ALD or ALE that is independent of loading.

[0037] Methods and apparatuses for processing a semiconductor substrate are provided herein to smooth a metal oxide film (e.g., a patterned metal oxide film) disposed on a substrate having a carbon-containing material. The metal oxide film can be used as a mask (e.g., a next-generation EUV photoresist (PR) type) to uniformly create etched and smooth edges in the imaged features after lithography. Such techniques improve LCDU, including improving LER of the features etched in the substrate. The disclosed embodiments reduce the need to perform EUV applications using high source power, thereby improving EUV scanner productivity. Additionally, the disclosed embodiments are also suitable for use in combination with etching a substrate to form structures such as contacts for source / drain regions, 3-D contact holes, etc. Further, the disclosed embodiments relate to etching and deposition processes selectively performed on the metal oxide film relative to the substrate positioned beneath the metal oxide film. The etching and deposition processes "smooth" the metal oxide film, e.g., reducing undesired non-uniformities of the metal oxide film without disturbing or damaging the underlying carbon-containing material of the substrate.

[0038] The method involves atomic layer etching (ALE) and selective deposition to gently etch and smooth materials such as metal oxide materials. Examples of metal oxide materials that can be etched using the disclosed embodiments include metal oxide PRs such as those made from tin (Sn), hafnium (Hf), zirconium (Zr), and / or the like.

[0039] ALE is a technique for removing thin layers of material using sequential self-limiting reactions. Generally, ALE can be performed using any suitable technique. Examples of atomic layer etching techniques are described in U.S. Patent No. 8,883,028, issued November 11, 2014, U.S. Patent No. 8,808,561, issued August 19, 2014, and U.S. Patent No. 9,576,811, issued February 21, 2017, which are hereby incorporated by reference herein for the purpose of describing exemplary atomic layer etching and etching techniques. In various embodiments, ALE can be carried out using a plasma, or can be carried out in a thermal manner.

[0040] ALE can be carried out in cycles. The concept of an "ALE cycle" is relevant to the discussion of various embodiments herein. Generally, an ALE cycle is the smallest set of operations for performing one etching process (e.g., etching a single layer). The result of one cycle is the etching of at least some of the film layers on the substrate surface. Generally, an ALE cycle includes a modification operation to form a reaction layer, followed by a removal operation to remove or etch only this modified layer. The cycle can include certain auxiliary operations, such as sweeping away one of the reactants or by-products. Generally, a cycle includes an example of a unique series of operations. For example, an ALE cycle can include the following operations: (i) delivering a reactant gas (adsorption), (ii) sweeping the reactant gas out of the chamber, (iii) delivering a removal gas and optionally a plasma (desorption), and (iv) sweeping the chamber.

[0041] Figure 1 Two exemplary schematic diagrams of an ALE cycle and a schematic diagram of selective deposition are shown. 171a to 171e show an exemplary ALE cycle. In 171a, a metal oxide film or substrate is provided. The metal oxide substrate can be disposed on a carbon-containing layer (not shown). In certain embodiments, the metal oxide substrate can be patterned on an underlying carbon layer comprising a carbon material, all of which are disposed on a semiconductor substrate such as a silicon wafer. The term "metal oxide substrate" is used herein to denote the metal oxide film or substrate as described, while the term "wafer" will be used to generally mean a silicon wafer on which the metal oxide substrate (and the underlying carbon-containing layer) can be disposed.

[0042] In various embodiments, the metal oxide film or substrate can be disposed on a silicon wafer such as a 200 mm wafer, a 300 mm wafer, or a 450 mm wafer, which includes a wafer having one or more layers of material (e.g., a dielectric material, a conductor material, or a semiconductor material deposited thereon). In some embodiments, the wafer can include a silicon (e.g., amorphous silicon) overlay, or a germanium overlay. The wafer can include a patterned mask layer previously deposited and patterned on the wafer. For example, a mask layer can be deposited and patterned on a substrate including a metal oxide overlay.

[0043] In some embodiments, the layers on the wafer can be patterned. The wafer can have "features", such as vias or contact holes, which can be characterized as one or more narrow and / or re-entrant openings, feature constrictions, and high aspect ratios. The features can be formed in one or more of the above layers. An example of a feature is a hole or via in a semiconductor wafer or a layer disposed on the wafer. Another example is a trench defined by a line or space in the wafer or a layer on the wafer. In multiple embodiments, the features can have an underlying layer, such as a barrier layer or an adhesion layer. Non-limiting examples of the underlying layer include dielectric layers and conductive layers, such as silicon oxide, silicon nitride, metal oxide, metal nitride, metal layers, silicon carbide, metal carbide, and other carbon-containing (e.g., amorphous carbon) layers.

[0044] In 171b, the surface of the metal oxide film, substrate, or layer is modified. In 171c, the modified layer is retained after a cleaning operation to remove excess unadsorbed precursors. In 171d, the modified layer is etched. In 171e, the modified layer is removed.

[0045] Similarly, 172a to 172e show an example of an ALE cycle for etching a metal oxide film. In some embodiments, 172a to 172e refer to an ALE cycle performed on a zirconia (ZrO 2 ) layer disposed on an underlying carbon-containing layer (not shown). In 172a, a substrate including a metal oxide material is provided.

[0046] In 172b, a modifier such as boron trichloride (BCl 3 ) gas is introduced into the metal oxide layer to modify the exposed surface of the metal oxide layer. The choice of the type of modifier employed can depend at least in part on the type of metal oxide material. In some embodiments, boron trichloride (BCl 3 ) gas can be the desired modifier, especially for achieving selectivity to the underlying carbon material. Other suitable metal oxide film modifiers that can be used in the context include chlorine gas (Cl 2 ) and hydrogen chloride gas (HCl).

[0047] The schematic diagram in 172b shows some modifiers such as BCl 3 being adsorbed on the surface of the metal oxide layer as an example. The modifier dissociates during the modification operation, for example, BCl 3 dissociates to form multiple independently separated Cl- ions, which form a thin reactive surface layer on the metal oxide layer. The reactive surface layer can be, for example, having an approximate chemical formula MCl xmetal chlorides that are more easily removed than the unmodified material located beneath the surface layer during this subsequent removal operation. In such a case where BCl 3 is used as the modifier, dissociated boron (B) can react with the oxygen provided by the metal oxide layer to form boron oxide (BO), which can be discharged from the reaction chamber as needed. A plasma containing the modifier can also be used during the modification or adsorption operation. A plasma containing the modifier can be generated by flowing a modifying chemical such as, for example, BCl 3 gas and igniting the plasma. Other modifying chemicals suitable for forming a plasma include, for example, reactants and / or reagents such as chlorine gas (Cl 2 ), hydrogen gas (H 2 ), and hydrogen bromide (HBr). Additional reactants can include, for example, compounds and substances such as chlorine (Cl), bromine (Br), and / or iodine (I), which can reactively bind to the metal oxide surface and are subsequently volatilized using sub-sputtering threshold ion bombardment. These modifiers can be used alone or in combination with a diluent inert gas, which includes, for example, helium (He), argon (Ar), neon (Ne), krypton (Kr), xenon (Xe), and combinations thereof. The selection and application of the modifier are based on their ability to volatilize the metal provided by the metal oxide layer (such as BCl 3 ). Alternatively, in certain embodiments, diborane gas (B 2 H 6 ) can be used instead of BCl 3 to similarly volatilize the metal from the metal layer. As shown in 172a - 172e in Figure 1 , this operation modifies the surface of the metal oxide material by several angstroms to form a modified layer having a weaker bond energy than the bulk metal oxide material beneath the modified surface.

[0048] In many embodiments, the modifier is provided to the metal oxide substrate as an unbiased or low-biased plasma. For example, in various embodiments, the modifier is introduced into a plasma processing chamber and the plasma source power is turned on to ignite the plasma to facilitate adsorption of the modifier onto the surface of the carbon-containing material. The bias can be applied at a low power or voltage (such as a self-bias between about 5V and about 15V or up to about 50V). It should be understood that the terms "bias power" and "bias voltage" are used interchangeably herein to describe the voltage at which the pedestal is set when a bias is applied to the pedestal. The bias power or bias voltage as described herein is measured in volts, which is represented by the unit "V" or "Vb", where b refers to bias.

[0049] In certain embodiments, the schematic diagram shown in 172b relates to a two-step process. For example, in order to treat zirconia (ZrO provided on a carbon-containing layer (not shown))2 ) ALE is performed on the layer or substrate: (1) Boron trichloride (BCl 3 ) gas is supplied to the reaction chamber, where this ALE process is carried out at a pressure of 60 mTorr and with the plasma power set to 300 - 900 W. The plasma can be provided by an inductively coupled plasma (ICP) source. A bias voltage of 0 V can be applied to the pedestal holding or supporting the substrate, such that the metal oxide layer thereon is maintained for 5 seconds within a temperature range of 0 - 60 °C; Next (2) Chlorine gas (Cl 2 ) is supplied to the same reaction chamber, in which this ALE process is carried out at a pressure of 10 mTorr and with the plasma power set to 100 - 300 W. The applied bias voltage can be within the range of 0 - 100 V and can be applied for a duration of 5 seconds within a temperature range of 0 - 60 °C.

[0050] At a temperature of 0 °C and a plasma power setting of 300 W, it can be used for two steps, and a bias voltage of 100 V is applied in step (2). An etching rate of approximately 1.1 Å / cycle can be observed. A further variation of the above two-step process can again involve replacing Cl with argon (Ar) gas 2 to achieve an etching rate of approximately 5 Å / cycle.

[0051] In other embodiments, ALE can be employed to etch aluminum oxide (Al 2 O 3 ). However, unlike the ALE of ZrO 2 , when chlorine gas (Cl 2 ) is applied in step (2), the ALE of Al 2 O 3 does not show a significant etching rate. Therefore, successful ALE of Al 2 O 3 typically requires the application of an argon-derived plasma in step (2).

[0052] Returning to what is shown in Figure 1 , in 172c, the modified chemical substance is swept out of the chamber. In 172d, an evacuation gas argon containing a directional plasma, such as Ar + plasma species and as indicated by the arrow, is introduced, and ion bombardment is carried out to remove the modified metal oxide surface of the metal oxide substrate. During this operation, a bias is applied to the metal oxide substrate to attract ions towards it. In the desorption operation, an inert gas plasma (e.g., He, Ar, Xe, or N 2) to remove the modified layer. Although argon gas is depicted in 172d, it should be understood that any suitable inert gas can be used to generate the plasma for this operation. In various embodiments, the bias power applied during removal can be between about 30V and about 100V. The bias power can be selected such that the energy provided to the metal oxide substrate is less than the energy required to sputter the metal oxide substrate but greater than the energy required to remove the modified layer from the metal oxide substrate. The plasma power can be set to a power between about 30W and about 500W

[0053] In 172e, the chamber is cleaned and these by-products are removed. In various embodiments, about 1 angstrom to about 130 angstroms of material can be removed in one cycle. After the ALE process, the etched surface of the metal oxide material is typically smooth. For example, in some embodiments, after the ALE process, the root mean square roughness of the surface can be less than about 0.5nm (R rms <0.5nm).

[0054] Figure 2 shows how this operation can reduce the presence of protrusions on the metal oxide photoresist PR. The size of the protrusions on the metal oxide PR can be in the range of about 1 angstrom to about 30 angstroms in diameter and / or height. As Figure 2 shown, a substrate 200 containing an exemplary metal oxide with a resist material and protrusions 299 is provided. A weak modifier 201 is provided and adsorbed onto the metal oxide substrate 200, which modifies the surface of the metal oxide substrate 200 to form a modified surface 202. The modified surface 202 is then removed; the dashed line 203 shows the position of the previous metal oxide material on the metal oxide substrate 200 to produce the current metal oxide substrate 210. The process 250 can constitute one ALE oxidation cycle. The process 260 shown below the process 250 shows a metal oxide substrate 220 with protrusions 298, and the protrusions 298 are exposed to a weak modifier 221. The volume of the protrusions 298 can be smaller than that of the protrusions 299 and / or the height can be shorter than that of the protrusions 299. The weak modifier 221 is adsorbed onto the metal oxide substrate 220, which modifies the surface of the metal oxide substrate 220 to form a modified surface 222. A weak modifier 231 is adsorbed onto the metal oxide substrate 230 to form a modified layer (not shown), and the modified layer is further removed to produce a metal oxide substrate 270, which includes a dashed line 275 that shows the original position of the previous metal oxide-containing material on the metal oxide substrate 230.

[0055] Without being bound to or limited by a particular theory, it is believed that Figure 2The scale of the metal-oxide-containing protrusions 299 and 298 shown is at the atomic level. As such, these protrusions 299 and 298 have a relatively large surface area to volume ratio, mainly due to their small (e.g., atomic) size. As introduced and discussed above, one or more weak modifiers are sequentially adsorbed onto the exposed surfaces of the metal-oxide-containing protrusions to modify the surface for subsequent removal. Specifically, the adsorption of the weak modifier onto the metal-oxide protrusions modifies the metal-oxide material layer thereon, for example, with a thickness of 3 to 4 atoms and / or atomic layers per layer, which is suitable for subsequent removal. Thus, upon completion of consecutive ALE operations, the height and / or overall size of these protrusions can be systematically reduced, for example, by making each ALE operation operative to remove one modified layer from the protrusion until the protrusion itself is substantially reduced and / or removed, ultimately "smoothing" the initially protrusion-bearing surface relative to the surrounding flat regions. Additionally, in certain embodiments, the ALE chemistry can be optimized based on the surface roughness, e.g., depending specifically on the height of the protrusions being attempted to be removed.

[0056] For example, as described above and shown by Figure 1 172d in Figure 3 shows how the removal operation can improve the smoothing of the etched material. The inert plasma species used in 172d is applied with a low bias such that the plasma species has sufficient energy to remove the modified surface of the weak modifier on the metal-oxide atoms adsorbed on the surface of the metal-oxide substrate. However, as applied, the inert plasma species does not have sufficient energy to sputter the underlying unmodified metal-oxide atoms below the top-exposed surface of the metal-oxide substrate. In various embodiments, the applied bias voltage can be between about 30V and about 100V, or less than about 50V. In some embodiments, each modified layer can be about 0.5 nm thick, which can include about 3 - 4 atomic layers. In some embodiments, there can be a phase boundary between the modified layer and the underlying amorphous material, as shown in Figure 3 For example Figure 3Inert plasma species such as Ar+ shown therein can be sub-threshold, non-reactive ion species, where sub-threshold means that the energy of the inert plasma species is not sufficient to sputter the material underlying the modified layer, but is sufficient to remove the modified layer. The threshold bias power or threshold bias voltage means the maximum bias voltage applied to the pedestal before sputtering the material on the substrate surface on the sputtering pedestal, such as a substrate containing metal oxide or a substrate having a metal oxide layer thereon. Thus, the threshold bias power depends locally on the material to be etched, the gas used to generate the plasma, the plasma power and the plasma frequency used to ignite the plasma. After each cycle, the surface can be "reset" so that the surface includes the material to be removed and there is not much or any modified material on the surface.

[0057] Further description regarding the use of ALE technology to smooth substrates is described in U.S. Provisional Patent Application No. 62 / 214,813, entitled "ALE SMOOTHNESS: IN AND OUTSIDE SEMICONDUCTOR INDUSTRY", filed on September 4, 2015, and U.S. Patent Application Publication No. 2017 / 0069462, entitled "ALE SMOOTHNESS: IN AND OUTSIDE SEMICONDUCTOR INDUSTRY", filed on August 31, 2016, the entire contents of which are incorporated herein by reference. Without being bound by a particular theory, it is believed that due to the layer-by-layer mechanism of ALE etching the material, the substrate can be smoothed by the disclosed embodiments, thereby etching and smoothing the protrusions on the substrate surface during each cycle. For example, the protrusions on the surface of the material to be smoothed can be modified and etched so that when the protrusions are etched, the size of the protrusions shrinks with each etching cycle, thereby smoothing the surface of the material.

[0058] As described above, although ALE processing can smooth sidewall or line edge roughness, ALE processing cannot change critical dimension (CD) variations, such as cannot change line width or hole / post diameter. To do so, a selective metal oxide deposition process is used to selectively deposit on the metal oxide layer and preferentially fill features with a carbon-containing material at different deposition rates to form features of different sizes. In various embodiments, the diameter of the holes or posts above the substrate is uniform and the LCDU is improved. For example, in some embodiments, metal oxide can be used as a suitable deposition material. Additionally, in certain embodiments, the deposition of metal oxide to fill features may involve an intermediate water (H 2 O) conversion step.

[0059] Return Figure 1, 182a - 182c show exemplary schematic diagrams of a selective deposition process that can be carried out according to certain disclosed embodiments. For the selective metal oxide deposition of a metal oxide layer relative to a carbon - containing substrate (not shown) positioned below the metal oxide layer, 182a shows a substrate with metal oxide atoms. In 182b, the metal oxide is exposed to a metal - oxide - containing chemical such as zirconium oxide (ZrO 2 ), such that the ZrO 2 material is selectively deposited onto the surface of the zirconium oxide substrate relative to the carbon - containing material positioned below the metal oxide film. In some embodiments, the metal - oxide - containing chemical can be combined with one or more diluents to produce a plasma. Exemplary diluents include nitrogen, helium, argon, hydrogen, and combinations thereof. In 182c, the chamber is purged to remove excess metal oxide, leaving only a specific amount of metal oxide on the surface of the metal oxide substrate or layer.

[0060] In certain embodiments, ZrO 2 can be deposited by ALD processing (such as those shown in 182a - 182c in Figure 1 ), using a thermal - driven half - reaction deposition of a zirconium (Zr) precursor (e.g., zirconium amide, zirconium halide, or zirconium alkoxide) and an oxygen (O) precursor (e.g., water, alcohol, ozone, oxygen) to produce ZrO 2 for ALD deposition. The deposition dosing time and pressure can depend on the type of precursor used. For example, for zirconium amide and water, a dosing time of 1 second at a partial pressure of 10 mTorr is sufficient to achieve a saturation thickness of 1 Å / ALD cycle. In contrast, halide and / or alkoxide precursors generally require longer dosing times or exposures. The temperature for deposition via ALD processing also typically depends on the thermal stability of the metal source used, such as the thermal stability of zirconium used as the metal source to produce zirconium oxide. For example, zirconium amide precursors are typically acceptable in a range extending from room temperature, e.g., about 20 °C - 25 °C, towards 250 °C. Alternatively, in certain embodiments, the ALD of aluminum oxide (Al 2 O 3 ) can be carried out in a manner similar to that of ZrO 2 ALD with similar limitations, but in addition to amide, halide, and alkoxide precursor choices, trimethylaluminum (i.e., alkylaluminum) can also be used.

[0061] Furthermore, in certain embodiments, a metal oxide can be deposited via ALD processing on a metal oxide layer, and this deposition is selective relative to the carbon - containing substrate below the metal oxide layer. For this selective deposition of the metal oxide, the oxygen - containing precursor used will not oxidize the carbon under the conditions described above. Oxygen - containing precursors suitable for metal oxide ALD include water (H 2(O) and alcohol (R-OH).

[0062] Figure 4 Show how selective metal oxide deposition can reduce the presence of depressions in the surface of the metal oxide-containing layer, film or substrate 400 to smooth it. As introduced earlier, the smoothed metal oxide layer can be used as a PR mask to etch a carbon-based substrate located below the metal oxide film, resulting in improved local critical dimensions (LCDs) of the features etched in the carbon-based substrate. During 182b, the metal oxide-containing chemical is delivered to the metal oxide-containing substrate 400 and adsorbed onto the surface of the metal oxide material on the substrate 400. The metal oxide material can be deposited into cracks, such as Figure 4 the cracks 450 formed in the metal oxide-containing layer or substrate 400 shown in, to fill the cracks 450 with the metal oxide material to smooth the cracks relative to the surrounding flat area of the metal oxide layer 400. The deposition of the metal oxide material via ALD can be a self-limiting process.

[0063] In addition, as also Figure 4 shown, the selective deposition via the above ALD process can include deposition on protrusions (499) such as photoresist. Similar to that used earlier to reduce and / or remove protrusions via ALE processing, ALD is particularly useful for filling cracks on the surface of the metal oxide layer. Similar to protrusions, these cracks can be at the atomic level scale and thus also have a high surface area to volume (e.g., void volume) ratio. Without being bound by a particular theory, it is believed that since the scale of the cracks on the metal oxide surface can be at the atomic level, depositing metal oxide into these cracks, such that the deposited metal oxide is uniformly adsorbed onto the surface of the substrate, will result in more material being deposited in the cracks rather than on the adjacent relatively flat surface of the substrate, thereby reducing the presence of cracks with each deposition cycle. Thus, the deposition of the metal oxide material can be carried out on the exposed surface within the cracks in the metal oxide layer to fill the cracks, thereby effectively smoothing the cracks relative to the surrounding flat area of the metal oxide layer.

[0064] In some embodiments, the substrate may also be exposed to an inert plasma after exposing the substrate to a metal oxide-containing chemical. The inert plasma may be generated by flowing any one or more of hydrogen, helium, nitrogen, argon, and neon and igniting the plasma. The plasma may be ignited using a plasma power between about 30 W and about 500 W. Without being bound by particular theory, it is believed that exposing the substrate to the inert plasma allows for slight etching and / or refreshing of adjacent surfaces of the metal oxide-containing material (e.g., PR) on the substrate to prevent deposition, thus resulting in selective deposition. The exposure to the metal oxide-containing chemical and the inert plasma may be performed in one or more cycles.

[0065] In addition, in some embodiments, metal oxide deposition may be performed by varying the above-described ALD process, which involves using a silicon (Si) or tin (Sn) reagent that provides an oxide-based plasma. A slight bias may be applied to the pedestal supporting the substrate containing the metal oxide to direct the deposition flux to the pedestal.

[0066] Using a combination of the ALE techniques and selective ALD described herein, the metal oxide material on the substrate can be processed to result in smooth, uniform features, which are particularly useful for EUV applications.

[0067] Figure 5 A simplified process flow diagram of a process flow 500 is shown, which shows an ALE process 508, followed by an ALD process 512, to reduce protrusions and fill cracks within the metal oxide layer or film, respectively. The process flow 500 begins at operation 502 and proceeds to operation 504, which involves exposing the metal oxide film to a boron halide reactant. A first plasma is ignited with a first bias power to modify the exposed surface of the metal oxide film. Secondly, at operation 506, the modified surface of the metal oxide film is exposed to a second plasma at a second bias power for a time sufficient to remove the modified surface without sputtering. The processes performed in operations 504 and 506 may be collectively referred to as the ALE process 508 and are performed to reduce and / or remove surface protrusions, as described earlier than Figure 2 and 3 described. Secondly, at operation 510, a metal oxide material is selectively deposited to fill cracks within the metal oxide film. The deposition is via ALD and is selective relative to the carbon-containing substrate on which the metal oxide film is located. Then, the process flow 500 ends at operation 514. Those skilled in the art will understand that the process flow 500 may be performed one or more times as needed to achieve the desired level of smoothness and / or may be further adjusted to achieve a specific smoothness goal.

[0068] Figure 6is a detailed process flow diagram of an embodiment for performing ALE and selective carbon deposition. Figure 6 The operations of can be performed in a chamber with a chamber pressure between about 5 mTorr and about 100 mTorr. It can be performed at a substrate temperature between about 20 °C and about 250 °C Figure 5 the operations of. The substrate temperature should be understood to mean the temperature set by the pedestal or wafer holder that holds the substrate. Figure 6 The operations shown in summarize the above regarding Figure 1 the operations performed. For example, in operation 601, a substrate including a metal oxide-containing material is provided to the chamber. As described above, the metal oxide-containing material can include zirconia (ZrO 2 ). Operation 601 can correspond to the schematic diagrams depicted in 171a and 172a of Figure 1 . In operation 603, the substrate is exposed to a modifying chemical substance such as a strong or weak modifier to modify the surface of the substrate. In various disclosed embodiments, the metal oxide-containing material on the surface is modified. This operation can correspond to the schematic diagrams depicted in 171b and 172b of Figure 1 and Figure 2 . In operation 605, the chamber is optionally purged to remove excess modifying chemical substance (e.g., weak modifier, i.e., CO 2 ). This operation can correspond to 172d of Figure 1 and 3 . The chamber can be cleaned by evacuating the chamber or stopping the flow of the modifying chemical substance and flowing a non-reactive inert gas such as helium or argon to remove excess gaseous modifying chemical substance. In operation 607, the substrate is exposed to an inert gas plasma to remove the modified surface. During operation 607, a bias is applied to generate sufficient energy for the inert gas plasma to remove the modified surface without sputtering the substrate. In operation 609, the chamber is optionally purged to remove gaseous modified material from the chamber. In operation 611, operations 603 - 609 can be optionally cycled and repeated. In operation 623, the substrate is exposed to a metal oxide-containing chemical substance to adsorb a layer of metal oxide-containing material onto the substrate. This can be used in some embodiments to fill cracks on the metal oxide-containing surface of the substrate. This operation can correspond to 172e of Figure 1 and 4of 182a. In some embodiments, the substrate may be cleaned one or more times between performing any of the operations. In various embodiments, operations 603 - 699 may optionally be repeated one or more cycles, each cycle being performed with or without a cleaning operation as shown. In operation 625, the chamber may optionally be cleaned. It should be understood that any suitable cleaning technique may be used to perform the cleaning operations as described herein, by pumping gas from the chamber, by flowing one or more inert gases, or a combination thereof. In operation 699, it is determined whether the substrate has been etched sufficiently to form the desired surface on the substrate. If not, operations 603 - 699 may optionally be repeated n cycles, where n is an integer equal to or greater than 1. In some embodiments, operation 623 is repeated only in some but not all of the repeated cycles, while in some embodiments, operation 623 is repeated in each cycle.

[0069] By combining ALE processing and selective ALD processing, both LCDU and LER of metal oxide-containing PR features are improved. In certain embodiments, this improvement may then be transferred to the underlying hard mask (e.g., SiO 2 / SiN layer), and thus to the structure of interest, resulting in improved variability and performance of the device.

[0070] The ALE operations disclosed above are gentle and precise, removing a digital amount of material per cycle, and thus can be easily controlled without over-etching the soft metal oxide PR material. Similarly, the metal oxide selective deposition can be performed using low source power (e.g., transformer coupled plasma or TCP) without bias and can deposit without damaging the resist.

[0071] In some embodiments, the selective metal oxide deposition may be optional. For example, these particular embodiments may be used in applications that can tolerate an increase in critical dimension.

[0072] In certain embodiments, if the original critical dimension is to be maintained throughout the patterning process using photoresist, the combination of the disclosed ALE operations and selective metal oxide deposition may be used on the metal oxide-containing material to improve LCDU and restore the critical dimension.

[0073] Device

[0074] The disclosed embodiments may be carried out in any suitable etching chamber or device, such as those available from Lam Research Corporation of Fremont, California, USA This can be carried out in an FX. Another example of a plasma etch chamber that can be used is the Flex available from Lam Research Corp. of Fremont, California. TM Reactive ion etch tool. Further descriptions of plasma etch chambers can be found in U.S. Patent Nos. 6,841,943 and 8,552,334, the entire contents of which are incorporated herein by reference.

[0075] In some embodiments, an inductively coupled plasma (ICP) reactor can be used. Figure 7 An example is provided in. Such an ICP reactor is also described in U.S. Patent No. 9,362,133, titled "METHOD FOR FORMING A MASK BY ETCHING CONFORMAL FILM ON PATTERNED ASHABLEHARDMASK," filed on December 10, 2013 and issued on June 7, 2016, which is incorporated herein by reference to describe a suitable ICP reactor for implementing the techniques described herein. Although ICP reactors are described herein, in some embodiments, it should be understood that capacitively coupled plasma reactors can also be used. Exemplary etch chambers or apparatuses can include a chamber having chamber walls, a chuck for holding a substrate or wafer to be processed, an RF power source configured to supply power to a coil to generate a plasma, and a gas flow inlet for inputting gases as described herein. The chuck can include an electrostatic electrode for clamping and releasing the wafer and can be charged using the RF power source. For example, a modified chemical gas and / or a selective deposition chemical can be flowed into the etch chamber to perform ALE and / or selective deposition, respectively. In some embodiments, the apparatus can include more than one chamber, each chamber being usable for etching, depositing, or processing a substrate. The chamber or apparatus can include a system controller for controlling some or all of the operations of the chamber or apparatus, such as regulating the chamber pressure, inert gas flow rate, plasma power, plasma frequency, reactive gas flow rate (e.g., a weak modifier gas, a carbon-containing gas, etc.); bias power, temperature, vacuum settings; and other processing conditions. The chamber can also be used for selectively depositing a carbon-containing material onto a substrate.

[0076] Figure 7 A cross-sectional view schematically showing an inductively coupled plasma integrated etch and deposition apparatus 700 suitable for implementing certain embodiments herein, an example of which is Kiyo TMA reactor, manufactured by Lam Research Corp. of Fremont, California. The inductively coupled plasma deposition apparatus 700 includes an integral processing chamber 701 structurally defined by a chamber wall 701 and a window 711. The chamber wall can be made of stainless steel or aluminum. The window 711 can be made of quartz or other dielectric materials. An optional internal plasma grid 750 divides the integral processing chamber 701 into an upper sub-chamber 702 and a lower sub-chamber 703. In most embodiments, the plasma grid 750 can be removed to utilize the chamber space formed by the sub-chambers 702 and 703. A chuck 717 is positioned in 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 etching and deposition processes are performed. The chuck 717 can be an electrostatic chuck for supporting the wafer 719 when the wafer 719 is present. In some embodiments, an edge ring (not shown) surrounds the chuck 717 and has an upper surface substantially in the same plane as the top surface of the wafer 719 (when the wafer is above the chuck 717). The chuck 717 also includes electrostatic electrodes for clamping and releasing the wafer. A filter and a DC clamp power supply (not shown) can be provided for this purpose. Other control systems can also be provided for lifting the wafer 719 away from the chuck 717. The chuck 717 can be charged with an RF power supply 723. The RF power supply 723 is connected to a matching circuit 721 through a connector 727. The matching circuit 721 is connected to the chuck 717 through a connector 725. In this way, the RF power supply 723 is connected to the chuck 717.

[0077] Elements for plasma generation include a coil 733 located above the window 711. In some embodiments, the coil is not used in the disclosed embodiments. The coil 733 is made of a conductive material and includes at least one full turn. In Figure 6 the example of the coil 733 shown, includes three turns. The cross-section of the coil 733 is shown with symbols, where a coil with an "X" symbol indicates that the coil 733 extends rotationally into the page, and conversely, a coil with a "●" symbol indicates that the coil extends rotationally out of the page. Elements for generating plasma also include an RF power supply 741 configured to provide RF power to the coil 733. Generally, the RF power supply 741 is connected to a matching circuit 739 through a connector 745. The matching circuit 739 is connected to the coil 733 through a connector 743. In this way, the RF power supply 741 is connected to the coil 733. An optional Faraday shield 749 is positioned between the coil 733 and the window 711. The Faraday shield 749 is held in a spaced relationship relative to the coil 733. The Faraday shield 749 is disposed directly above the window 711. The coil 733, the Faraday shield 749, and the window 711 are each configured to be substantially parallel to each other. The Faraday shield can prevent metal or other substances from depositing on the dielectric window 711 of the plasma chamber 701.

[0078] Processing gases (such as oxygen, carbon dioxide, methane, etc.) can flow into the processing chamber 701 through one or more gas inlets 760 located in the upper chamber 702 and / or through one or more side gas inlets 770. Similarly, although not explicitly shown, similar gas inlets can be used to supply processing gases to a capacitively coupled plasma processing chamber. A vacuum pump, for example, a single-stage or two-stage dry mechanical pump and / or a turbomolecular pump 740, can be used to evacuate the processing gas from the processing chamber 701 and maintain the pressure inside the processing chamber 701. For example, the pump can be used to evacuate the chamber 701 during an ALD purge operation. A valve-controlled conduit can be used to fluidly connect the vacuum pump to the processing chamber 701 to selectively control the application of the vacuum environment provided by the vacuum pump. During the operation of the plasma processing, this can be done using a closed-loop controlled flow restriction device such as a throttle valve (not shown) or a pendulum valve (not shown). Similarly, a vacuum pump and a valve fluidly connected to the capacitively coupled plasma processing chamber in a controlled manner can also be used.

[0079] During the operation of the device, one or more processing gases can be supplied through the gas inlets 760 and / or 770. In certain embodiments, the processing gas can 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 can replace more complex gas inlets, for example, replaced by one or more showerheads. The Faraday shield 749 and / or the optional grid 750 can include internal channels and holes for delivering the processing gas to the interior of the chamber 701. One or both of the Faraday shield 749 and the optional grid 750 can act as a showerhead for delivering the processing gas. In some embodiments, a liquid evaporation and delivery system can be located upstream of the chamber 701 such that once the liquid reactant or precursor is evaporated, the evaporated reactant or precursor is introduced into the chamber 701 through the gas inlets 760 and / or 770.

[0080] RF power is supplied from the RF power source 741 to the coil 733 to cause 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 sub-chamber 702. The physical and chemical interactions of the generated ions and radicals with the wafer 719 selectively etch features and deposit layers on the wafer.

[0081] If a plasma grid is used such that both an upper sub-chamber 702 and a lower sub-chamber 703 exist, the induced current acts on the gas present in the upper sub-chamber 702 to generate an electron-ion plasma in the upper sub-chamber 702. The optional internal plasma grid 750 limits the amount of hot electrons in the lower sub-chamber 703. In some embodiments, the device is designed and operated such that the plasma present in the lower sub-chamber 703 is an ion-ion plasma.

[0082] Both the upper electron-ion plasma and the lower ion-ion plasma can contain cations and anions, but the ion-ion plasma will have a greater anion-to-cation ratio. Volatile etch and / or deposition by-products can be removed from the lower sub-chamber 703 through port 722. The chuck 717 disclosed herein can operate in an elevated temperature range between about 10 °C and about 250 °C. This temperature will depend on the processing operation and the specific recipe.

[0083] The chamber 701 can be coupled to a facility (not shown) when installed in a clean room or a manufacturing plant. The facility includes ducts that provide process gases, vacuum, temperature control, and environmental particle control. These facilities are coupled to the chamber 701 when installed in the target manufacturing plant. Additionally, the chamber 701 can be coupled to a transfer chamber, allowing for the transfer of semiconductor wafers in and out of the chamber 701 by machine means using typical automation.

[0084] In some embodiments, a system controller 730 (which can include one or more physical or logical controllers) controls some or all of the operations of the processing chamber. The system controller 730 can include one or more memory devices and one or more processors. In some embodiments, the device includes a switching system for controlling flow rate and duration when performing the disclosed embodiments. In some embodiments, the device can have a switching time of up to about 500 ms or up to about 750 ms. The switching time can depend on the flowing chemical, recipe selection, reactor architecture, and other factors.

[0085] The processing chamber 701 or apparatus may include a system controller. For example, in some embodiments, the controller 730 is part of a system that may be part of the above examples. Such systems may include semiconductor processing apparatuses that include one or more processing tools, one or more processing chambers, one or more platforms for processing, and / or specific processing components (wafer chucks, gas flow systems, etc.). These systems may be integrated with electronics for controlling their operations before, during, and after processing semiconductor wafers or substrates. The electronics may be referred to as a "controller" that may control various components or sub-parts of one or more systems. Depending on the processing requirements and / or the type of system, the controller 730 may be programmed to control any of the processes disclosed herein, including controlling process gas delivery, 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 operation settings, wafer transfer into and out of tools and other transfer tools, and / or load locks coupled or interfaced to specific systems.

[0086] Broadly speaking, the controller 730 may be defined as an electronic device having various integrated circuits, logic, memory, and / or software for receiving instructions, issuing instructions, controlling operations, enabling cleaning operations, enabling endpoint measurements, etc. The integrated circuits may include chips in the form of firmware storing program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers executing 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 operating parameters for performing specific processes on or with respect to semiconductor wafers or systems. In some embodiments, the operating parameters may be part of a recipe defined by a process engineer for performing one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer. For example, the controller and the processor may be operatively coupled at least to the flow control hardware, and the memory may store computer-executable instructions for controlling the processor to control the flow control hardware by exposing a metal oxide film to a boron halide reactant and igniting a first plasma with a first bias power to modify the surface of the metal oxide film; exposing the modified surface of the metal oxide film to a second plasma with a second bias power for a time sufficient to remove the modified surface without sputtering; and selectively depositing a metal oxide material on the metal oxide film to fill cracks in the metal oxide film.

[0087] In some implementations, the controller 730 can be part of a computer that is integrated with, coupled to, or networked to the system or combinations thereof. For example, the controller 630 can be in the "cloud" or be all or part of a wafer fab host system, which can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of manufacturing operations, examine the history of past manufacturing operations, examine trends or performance criteria of multiple manufacturing operations, to change parameters of the current process, set up process operations to follow the current process or initiate a new process. In some instances, a remote computer (e.g., a server) can provide a process recipe to the system via a network, which can include a local network or the Internet. The remote computer can include a user interface capable of inputting or programming parameters and / or settings, which are then communicated from the remote computer to the system. In some instances, the controller receives instructions in the form of data that specify parameters for each process step to be performed during one or more operations. It should be understood that the parameters can be for the type of process to be performed as well as the type of tool, and the controller is configured to connect to or control the tool. Thus, as described above, the controller can be distributed, for example, by including one or more discrete controllers that are connected together via a network and work towards a common goal (e.g., the processing and control described herein). An example of a distributed controller for these purposes can be one or more integrated circuits on a chamber that communicate with one or more remote integrated circuits (e.g., at the platform level or as part of a remote computer), which combine to control processing within the chamber.

[0088] Exemplary systems can include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that can be associated with or used in the preparation and / or manufacture of semiconductor wafers.

[0089] As described above, depending on one or more process steps to be performed by the tool, the controller 730 can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, adjoining tools, tools located throughout the factory, hosts, another controller, or tools used in a material handling that transports a container of wafers between tool locations and / or load ports in a semiconductor manufacturing facility.

[0090] The processing chamber 701 can be integrated as Figure 8In the multi-station tool shown, each station can be used to perform different operations. For example, one station can be used to perform ALE, while another station is used for selective deposition. The disclosed embodiments can be performed without breaking the vacuum and can be carried out in the same apparatus. In various embodiments, ALE and selective deposition are performed without breaking the vacuum. In various embodiments, ALE and selective deposition are performed in the same chamber.

[0091] Figure 8 A semiconductor processing cluster structure is described, in which individual modules interface with a vacuum transfer module 838 (VTM). The configuration of the transfer module that "transfers" wafers between multiple storage and processing modules can be referred to as a "cluster tool architecture" system. An airtight chamber 830 (also referred to as a load lock or transfer module) is shown in a VTM 838 having four processing modules 820a - 820d, which can be individually optimized to perform various manufacturing processes. For example, the processing modules 820a - 820d can be implemented to perform substrate etching, deposition, ion implantation, wafer cleaning, sputtering, and / or other semiconductor processes. In some embodiments, ALE and selective deposition are performed in the same module. In some embodiments, ALE and selective deposition are performed in different modules within the same tool. One or more of the substrate etching processing modules (any of 820a - 820d) can be implemented as disclosed herein, i.e., for performing ALE, selectively depositing a carbon-containing material, and other suitable functions according to the disclosed embodiments. The airtight chamber 830 and the processing modules 820 can be referred to as "stations". Each station has a facet 836 that connects the station to the VTM 838. Inside each facet, sensors 1 - 18 are used to detect the passage of the substrate 826 as it moves between stations.

[0092] A robot 822 transfers the wafer 826 between stations. In one embodiment, the robot 822 has one arm, while in another embodiment, the robot 822 has two arms, where each arm has an end effector 824 to pick up a wafer (e.g., wafer 826) for transportation. In an atmospheric transfer module (ATM) 840, a front-end robot 832 is used to transfer the wafer 742 from a wafer cassette or front-opening unified pod (FOUP) 834 in a load port module (LPM) 842 to the airtight chamber 830. A module center 828 within the processing module 820 is one location for placing the wafer 826. An aligner 844 in the ATM 840 is used to align the wafer.

[0093] In an exemplary processing method, a wafer is placed in one of a plurality of FOUPs 834 in the LPM 842. The front-end robot 832 transfers the wafer from the FOUP 834 to the aligner 844, which allows the wafer 826 to be properly centered before being etched or processed. After alignment, the wafer 826 is moved by the front-end robot 832 into the airtight module 830. Since the airtight module has the ability to match the environments between the ATM and the VTM, the wafer 826 can be moved between the two pressure environments without being damaged. From the airtight module 830, the wafer 826 is moved through the VTM 838 by the robot 822 and into one of the processing modules 820a - 820d. To effect such wafer movement, the robot 822 uses end effectors 824 on each of its arms. Once the wafer 826 has been processed, it is moved from the processing module 820a - 820d to the airtight module 830 by the robot 822. The wafer 826 can be moved from here to one of the plurality of FOUPs 834 or to the aligner 844 by the front-end robot 832.

[0094] It should be noted that the computer controlling the wafer movement can be local to the cluster architecture, or it can be located outside the cluster architecture in a manufacturing facility, or at a remote location and connected to the cluster architecture via a network. As previously referenced Figure 7 The controller described can be implemented with the tools in Figure 8 .

[0095] Conclusion

[0096] Although the foregoing embodiments have been described in considerable detail for purposes of clear understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the disclosure. Further disclosure is provided by way of the appended exemplary claims directed to some specific embodiments, but is not intended to be limiting. It should be noted that there are many alternative ways of implementing the processes, systems, and devices of the embodiments of the present invention. Accordingly, the embodiments of the present invention should be regarded as illustrative rather than restrictive, and the embodiments are not limited to the details given herein.

Claims

1. A method of treating a metal oxide film, the method comprising: Receiving an EUV-patterned metal oxide film on a carbon-based substrate in a processing chamber, whereby a portion of the carbon-based substrate is exposed in the patterned features of the metal oxide film ； And (a) Exposing the metal oxide film on the carbon-based substrate to a boron halide reactant and igniting a first plasma with a first bias to modify the surface of the metal oxide film; (b) Exposing the modified surface of the metal oxide film to a second plasma under a second bias and for a time sufficient to remove the modified surface without sputtering the underlying unmodified metal oxide film of the modified surface; And (c) Selectively depositing a metal oxide material on the metal oxide film relative to the carbon-based substrate to fill cracks on the surface of the metal oxide film.

2. The method according to claim 1, wherein the metal oxide film is smoothed by the deposition of the metal oxide material.

3. The method according to claim 2, wherein the smoothed metal oxide film is used as a mask to etch the carbon-based substrate positioned below the metal oxide film, resulting in an improvement in the local critical dimension (LCD) of the etched features in the carbon-based substrate.

4. The method according to claim 1, wherein (a) and (b) comprise an atomic layer etching (ALE) process.

5. The method according to claim 2, wherein (c) comprises an atomic layer deposition (ALD) process.

6. The method according to claim 5, wherein (a) and (b) comprise an atomic layer etching (ALE) process, and further wherein both the atomic layer etching process and the atomic layer deposition process are selective to act on the metal oxide film rather than the carbon-based substrate.

7. The method according to claim 6, wherein the metal oxide film is smoothed without damaging the carbon-based substrate.

8. The method according to claim 1, wherein the boron halide reactant is boron trichloride gas (BCl 3 ).

9. The method according to claim 1, wherein the second plasma is generated from chlorine gas (Cl 2 ).

10. The method according to claim 1, wherein the second plasma is generated by an argon-containing gas.

11. The method according to claim 1, wherein the first plasma is generated using a plasma power between 300 W and 900 W.

12. The method according to claim 5, wherein the first bias is 0 V and applied for 5 seconds.

13. The method according to claim 1, wherein the metal oxide film is a zirconia (ZrO 2 ) film.

14. The method according to claim 1, wherein the metal oxide film is aluminum oxide (Al 2 O 3 ).

15. The method according to claim 14, wherein the modified surface of the alumina (Al 2 O 3 ) membrane is exposed to the second plasma generated by the argon-containing gas.

16. The method according to claim 13, wherein the metal oxide material is zirconium oxide (ZrO 2 ).

17. The method according to claim 16, wherein the zirconia (ZrO 2 ) is deposited by thermal half-reactions of an ALD using a zirconium precursor and an oxygen-containing precursor, the zirconium precursor being selected from the group consisting of zirconium amides, zirconium halides, or zirconium alkoxides; and the oxygen-containing precursor being selected from the group consisting of water, alcohol, ozone, or oxygen.

18. The method according to claim 17, wherein a 1-second dosage of zirconium amide provided at a partial pressure of 10 mTorr reacting with water is sufficient to achieve a saturation thickness of 1 angstrom per ALD cycle.

19. The method according to claim 17, wherein the temperature at which the deposition is carried out depends on the thermal stability of the zirconium amide.

20. The method according to claim 17, wherein the deposition of the zirconium oxide (ZrO 2 ) by ALD is selective with respect to the carbon-containing material located below the metal oxide film, and further wherein the oxygen-containing precursor does not oxidize the carbon-containing material.

21. The method according to claim 14, wherein the metal oxide material is alumina (Al 2 O 3 ).

22. The method according to claim 21, wherein the aluminum oxide (Al 2 O 3 ) is deposited by thermal half-reactions of an ALD using an aluminum precursor and an oxygen-containing precursor, the aluminum precursor being selected from the group consisting of aluminum amides, aluminum halides, alkanolates of aluminum, or alkylaluminums; and the oxygen-containing precursor being selected from the group consisting of water, alcohols, ozone, or oxygen.

23. The method according to claim 22, wherein the alkylaluminum is trimethylaluminum.

24. An apparatus for treating a substrate, the apparatus comprising: (a) One or more processing chambers, each processing chamber comprising a chuck; One or more gas inlets leading to the processing chambers and associated flow control hardware; and (b) A controller having at least one processor and a memory, wherein The at least one processor and the memory are communicatively coupled to each other, the at least one processor is at least operatively coupled to the flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the flow control hardware by: receiving an EUV patterned metal oxide film on a carbon-based substrate in a processing chamber, whereby a portion of the carbon-based substrate is exposed in the patterned features of the metal oxide film ； and (i) exposing the metal oxide film on the carbon-based substrate to a boron halide reactant and igniting a first plasma with a first bias to modify the surface of the metal oxide film; (ii) exposing the modified surface of the metal oxide film to a second plasma at a second bias for a time sufficient to remove only the modified surface without sputtering the underlying unmodified metal oxide film of the modified surface; and (iii) selectively depositing a metal oxide material on the metal oxide film relative to the carbon-based substrate to fill cracks on the surface of the metal oxide film.

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