Vapor Deposition of Carbon-Doped Metal Oxides for Use as Photoresists

Abstract

Embodiments disclosed herein include a method of forming a metal-oxo photoresist on a substrate, in one embodiment, the method includes repeating a deposition cycle, each iteration of the deposition cycle including: a) flowing a metal precursor into a chamber containing the substrate, and b) flowing an oxidant into the chamber, where the oxidant and the metal precursor react to form the metal-oxo photoresist.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims priority to U.S. Patent Application No. 17 / 534,287, filed November 23, 2021, which claims the benefit of U.S. Provisional Application No. 63 / 126,977, filed December 17, 2020, the entire contents of which are incorporated herein by reference.

[0002] Embodiments of the present disclosure relate to the field of semiconductor processing, and more particularly, to a method of depositing a photoresist layer on a substrate using a vapor phase process.

Background Art

[0003] Lithography has been used for decades in the semiconductor industry to generate two - dimensional and three - dimensional patterns on microelectronic devices. The lithography process involves spin - on deposition of a film (photoresist), irradiating (exposing) the film with a selected pattern using an energy source (exposure), and removing (etching) either the exposed areas (positive tone) or non - exposed areas (negative tone) of the film by dissolving them in a solvent. A bake is performed to remove the remaining solvent.

[0004] The photoresist should be a radiation - sensitive material, and when irradiated, a chemical change occurs in the exposed portion of the film, enabling a change in solubility between the exposed and non - exposed regions. Using this change in solubility, either the exposed or non - exposed regions of the photoresist are removed (etched). This develops the photoresist, and the pattern can be transferred to the underlying thin film or substrate by etching. After the pattern is transferred, the remaining photoresist is removed, and by repeating this process multiple times, two - dimensional and three - dimensional structures used in microelectronic devices are generated.

[0005] Several properties are important in the lithography process. These important properties include sensitivity, resolution, lower line-edge roughness (LER), etching resistance, and the ability to form thinner layers. Higher sensitivity means that less energy is required to change the solubility of the deposited film, which allows for increased efficiency in the lithography process. Resolution and LER determine how narrow features can be achieved in the lithography process. Pattern transfer to form deep structures requires materials with higher etching resistance. Materials with higher etching resistance can also enable thinner films. Thinner films increase the efficiency of the lithography process. [Overview of the project]

[0006] Embodiments disclosed herein include a method for forming a metal-oxo photoresist on a substrate. In one embodiment, the method includes repeating a deposition cycle, each iteration of which includes a) flowing a metal precursor into a chamber containing a substrate, and b) flowing an oxidant into the chamber, wherein the oxidant and the metal precursor react to form a metal-oxo photoresist.

[0007] Additional embodiments include a method for forming a metal oxophotoresist on a substrate. In one embodiment, the method includes repeating a deposition cycle, each iteration of the deposition cycle including a) flowing a metal precursor into a chamber containing a substrate, and b) flowing an oxidant into the chamber, the oxidant and the metal precursor reacting to form a metal oxophotoresist. In one embodiment, the method further includes treating the metal oxophotoresist with plasma after a first number of iterations of the deposition cycle.

[0008] In yet another embodiment, a method for forming a metal oxophotoresist on a substrate is disclosed. In one embodiment, the method comprises repeating a deposition cycle, each iteration of which a) flows a metal precursor into a chamber containing a substrate, wherein the metal precursor is of the general formula MR X L Y It consists of, where X=0 to 4 and Y=4 - The steps include: a) purging the chamber; c) flowing an oxidant into the chamber, wherein the oxidant reacts with a metal precursor to form a metal oxophotoresist, the oxidant comprising one or more of water, O2, ethylene glycol, alcohol, peroxide, and acid; and d) purging the chamber. [Brief explanation of the drawing]

[0009] [Figure 1] This is a flowchart illustrating a process for depositing a metal oxophotoresist onto a substrate using a vacuum deposition process according to one embodiment. [Figure 2] This flowchart shows an additional process for depositing a metal oxophotoresist onto a substrate using a vacuum deposition process accompanied by plasma treatment, according to one embodiment. [Figure 3] This is a schematic plan view of a processing tool according to one embodiment that enables the use of a space atomic layer deposition process to deposit a metal oxophotoresist onto a substrate. [Figure 4A] This is a cross-sectional view of a substrate having a metal oxophotoresist according to one embodiment. [Figure 4B] This is a cross-sectional view of a substrate having a metal oxophotoresist having a first layer and a second layer, according to one embodiment. [Figure 5] This is a cross-sectional view of a processing tool that may be used to carry out the process shown in Figure 1 or Figure 2 according to an embodiment of the present disclosure. [Figure 6] A block diagram of an exemplary computer system according to one embodiment of the present disclosure is shown. [Modes for carrying out the invention]

[0010] This specification describes a method for depositing a photoresist onto a substrate using a vapor phase process. Numerous specific details are provided in the following description to provide a complete understanding of the embodiments of this disclosure. Those skilled in the art will see that embodiments of this disclosure can be carried out without these specific details. In other cases, well-known embodiments, such as the manufacture of integrated circuits, are not described in detail to avoid unnecessarily obscuring the embodiments of this disclosure. Furthermore, it should be understood that the various embodiments shown in the figures are illustrative and not necessarily drawn to scale.

[0011] To explain the background, the photoresist systems used in extreme ultraviolet (EUV) lithography suffer from low efficiency. Specifically, existing photoresist material systems for EUV lithography require high doses to provide the necessary solubility switch to enable the development of the photoresist material. Organic-inorganic hybrid materials (e.g., metal oxo material systems) have been proposed as material systems for EUV lithography due to their high sensitivity to EUV radiation. Such material systems typically contain metals (e.g., Sn, Hf, Zr, etc.), oxygen, and carbon. Furthermore, metal oxo-based organic-inorganic hybrid materials have been demonstrated to offer low LER and high resolution, properties necessary for forming narrow features.

[0012] Metal oxo material systems are currently deposited onto substrates using wet processes. The metal oxo material system is dissolved in a solvent and distributed onto a substrate (e.g., a wafer) using a wet chemical deposition process such as spin-coating. Wet chemical deposition of photoresists has several drawbacks. One of the downsides of wet chemical deposition is the generation of a large amount of wet byproducts. Because wet byproducts are undesirable, the semiconductor industry is actively working to reduce them as much as possible. Furthermore, wet chemical deposition can lead to heterogeneity problems. For example, spin-on deposition can result in photoresist layers with non-uniform thickness or distribution of metal oxo molecules. Additionally, metal oxo photoresist material systems have been shown to suffer from thickness reduction after exposure, which is problematic in lithography processes. Moreover, in spin-on processes, the proportion of metal in the photoresist is fixed and cannot be easily adjusted.

[0013] Accordingly, embodiments of the present disclosure provide a vacuum deposition process for providing a metal oxophotoresist layer. Vacuum deposition processes (e.g., atomic layer deposition (ALD) processes) address the shortcomings of the wet deposition processes described above. In particular, vacuum deposition processes have the following advantages: 1) eliminating the generation of wet byproducts, 2) providing a highly uniform photoresist layer, 3) minimizing thickness reduction after exposure, and 4) providing a mechanism to adjust the proportion of metal in the photoresist.

[0014] The embodiments disclosed herein provide a variety of vacuum deposition processes comprising the reaction of a metal precursor with an oxidant. In the first embodiment, the vacuum deposition process may be an ALD process. In some embodiments, the vacuum deposition process may be a thermal process. In other embodiments, the vacuum deposition process may be a plasma-enhanced (PE) deposition process (e.g., PE-ALD). The vacuum deposition process may further include plasma treatment (e.g., before deposition, after a predetermined number of deposition cycles, and / or after the last deposition cycle).

[0015] In addition to improving uniformity (e.g., thickness uniformity, uniformity of composition across the entire surface), using the ALD process provides significant flexibility in the composition (in the thickness direction) of metal oxo photoresists. For example, the composition can be modified by changing the precursor during various cycles of the deposition process. Such modifiable metal oxo structures allow for fine-tuning of the photoresist to suit a variety of applications. In one such application, the main portion of the metal oxo photoresist is optimized for dose, while different compositions near the interface with the underlying substrate are adjusted for adhesion, sensitivity to EUV photons, sensitivity to chemical development, etc. This improves post-lithography profile control, such as scumming, defects, and resist tilt / lift-off. Furthermore, the gradation of the metal oxo photoresist can be optimized depending on the pattern type. For example, pillars may require improved adhesion, while line / space patterns may require lower adhesion and can be optimized for improved dose sensitivity.

[0016] In one embodiment, the vacuum deposition process relies on a chemical reaction between a metal precursor and an oxidant. The metal precursor and oxidant are vaporized toward a vacuum chamber. The metal precursor reacts with the oxidant to form a photoresist layer containing the metal oxo on the surface of the substrate. In some embodiments, the metal precursor and oxidant are supplied to the vacuum chamber in alternating pulses. In ALD or PE-ALD processes, the vacuum chamber may be purged between pulses of the metal precursor and oxidant.

[0017] Referring to Figure 1, a process 100 for depositing a metal oxophotoresist on a substrate according to one embodiment is shown. In one embodiment, the metal oxophotoresist is deposited on a substrate such as a silicon wafer, but is not limited thereto. It should be understood that the substrate may not contain materials other than silicon.

[0018] In one embodiment, process 100 is initiated by operation 101 of supplying a metal precursor to a vacuum chamber containing a substrate. In one embodiment, the metal precursor is of general formula MR X L Y This can consist of X=0 to 4 and Y=4 -It is X. M is a metal such as one or more of Sn, Hf, Zr, Co, Cr, Mn, Fe, Cu, Ni, Mo, W, Ta, Os, Re, Pd, Pt, Ti, V, In, Sb, Al, As, Ge, Se, Cd, Ag, Pb, Au, Er, Yb, Pr, La, Na, and Mg. In one embodiment, R is alkyl (e.g., C1-C10). The alkyl may be a straight-chain alkyl, a branched alkyl, or a cyclic alkyl (e.g., tBu, nBu, Sec-butyl, or iPr). R may further be alkenyl, alkynyl, aryl, or benzyl. Structures (1) and (2) are diagrams showing examples of a pair of suitable MR structures. In one embodiment, L is an alkyl (C1-C10) amino such as dimethylamino or methylethylamino. L further includes Cl, Br, CN, CNO, SCN, N3, or SeCN. Structures (3), (4), and (5) are diagrams showing examples of suitable ML structures. An example of a complete metal precursor (e.g., a tin precursor) is shown in structure (6). The R component can be modified to change the exposure sensitivity of the metal oxide film. The reactivity between the metal precursor and the oxidant can be adjusted by changing R and / or L on the metal precursor.

[0019] In one embodiment, a single metal precursor species can flow into the chamber. In other embodiments, two or more different metal precursor species can flow into the chamber. For example, in some embodiments, metal precursors having various metals M can be used. In one embodiment, the metal precursor can flow into the chamber by itself. In other embodiments, an inert carrier gas can further flow into the chamber together with the metal precursor. The carrier gas may be an inert gas such as Ar, N2, He. In one embodiment, the metal precursor is adsorbed on the surface of the substrate.

[0020] In one embodiment, process 100 may proceed to operation 102, which includes purging the vacuum chamber. The purging operation is optional in some embodiments. That is, in some embodiments, process 100 may proceed directly from operation 101 to operation 103. Purging the chamber may include flowing an inert gas such as Ar, N2, or He into the chamber.

[0021] In one embodiment, process 100 may proceed to operation 103, which includes supplying an oxidant into the vacuum chamber. The oxidant reacts with the metal precursor to form a metal oxo film on the substrate. Generally, the metal oxo film includes M - O bonds and M - C bonds in the MOC network. Upon exposure (e.g., UV or EUV light), the M - C bonds are broken, and the proportion of carbon in the film decreases. This results in selective etching during the development process. In one embodiment, the oxidant may include one or more of water, O2, ethylene glycol, alcohol (e.g., methanol, ethanol, etc.), peroxide (e.g., H2O2), and acid (e.g., formic acid, acetic acid, etc.).

[0022] In one embodiment, process 100 may proceed to operation 104, which includes purging the vacuum chamber. The purging operation is optional in some embodiments. That is, in some embodiments, process 100 may proceed directly from operation 103 to operation 101. Purging the chamber may include flowing an inert gas such as Ar, N2, or He into the chamber.

[0023] As indicated by the arrow from operation 104 to operation 101, process 100 may be repeated any number of cycles to provide a metal oxo film of a desired thickness. In one embodiment, the same process gas is used in each iteration of the deposition cycle. In other embodiments, the process gas may be changed between cycles. For example, the first deposition cycle may utilize a first metal precursor vapor, and the second deposition cycle may utilize a second metal precursor vapor. In some embodiments, subsequent deposition cycles may alternate between the first metal precursor vapor and the second metal precursor vapor. In one embodiment, multiple oxidant vapors may alternate between cycles in a similar manner. In yet another embodiment, a metal oxo layer with high adhesion can be provided using the first metal precursor and the first oxidant, and subsequent deposition cycles with the second metal precursor and the second oxidant can provide high sensitivity to the metal oxo film.

[0024] In one embodiment, each of the processing operations 101 to 104 may be performed for an arbitrary duration. For example, processing operations 101 to 104 may be performed for a duration ranging from approximately 1 millisecond to 1 minute. In some embodiments, the durations of each operation 101 to 104 do not need to be the same. The durations of each operation 101 to 104 may also differ between deposition cycles.

[0025] In one embodiment, process 100 is carried out as a thermal process; that is, process 100 can be carried out without plasma. Such a process may be called an ALD process in some embodiments. In one embodiment, the temperature of the substrate may be maintained between approximately -40°C and approximately 500°C.

[0026] In yet another embodiment, plasma may be ignited during one or more of the processing operations 101-104. In such a case, the presence of plasma may enhance the chemical reactions used to form the metal oxophotoresist. Such embodiments may be referred to as PE-ALD processes. In one embodiment, any plasma source may be used to form the plasma. For example, the plasma source may include, but is not limited to, a capacitively coupled plasma (CCP) source, an inductively coupled plasma (ICP) source, a remote plasma source, or a microwave plasma source.

[0027] In the illustrated embodiment, process 100 is shown to begin with operation 101. However, it should be understood that process 100 may begin with any of processing operations 101 to 104. For example, to improve adhesion between the metal precursor and the substrate, starting with operation 103 may be helpful in treating the surface of the substrate.

[0028] In one embodiment, the vacuum chamber used in process 100 may be any suitable chamber capable of providing sub-atmospheric pressure. In one embodiment, the vacuum chamber may include temperature control features for controlling the chamber wall temperature and / or the substrate temperature. In one embodiment, the vacuum chamber may further include features for supplying plasma into the chamber. A detailed description of a suitable vacuum chamber is provided in reference to Figure 3 or Figure 5.

[0029] It will be understood that specific processing parameters may be selected during process 100 to improve one or more properties of the metal oxo film. Generally, process conditions may include a showerhead temperature between about -20°C and about 175°C. The pedestal temperature may further be between about -20°C and about 175°C. In one embodiment, the pressure in the chamber may be less than about 10T. In other embodiments, the pressure may be between about 0.01T and about 10T. The distance between the substrate and the showerhead may be between about 100 mil and about 4,000 mil. With respect to gas flow, the precursor gas may have a flow rate between about 0.1 slm and about 5 slm. The precursor flow rate may include a carrier gas (e.g., Ar or N2). The oxidant (e.g., H2O) flow rate may be between about 50 mgm and about 500 mgm. A carrier gas (e.g., Ar or N2) may be used to deliver the oxidant into the chamber. The carrier gas can have a flow rate between approximately 0.01 slm and approximately 5 slm.

[0030] Referring now to Figure 2, a flow chart of process 210 according to an additional embodiment is shown. In one embodiment, process 210 may begin with operation 211. Operation 211 may include processing a substrate in a vacuum chamber with plasma treatment. Operation 211 may be used to prepare the surface of the substrate to improve adhesion with a metal oxo film. In some embodiments, the initial plasma treatment operation 211 is optional. That is, in some embodiments, process 210 may begin with operation 212.

[0031] In one embodiment, operation 212 may include supplying a metal precursor to a vacuum chamber containing a substrate. In one embodiment, the metal precursor may be substantially the same as the metal precursor described in process 100, which will not be repeated here.

[0032] In one embodiment, process 210 may proceed to operation 213, which includes purging the vacuum chamber. In one embodiment, the purging operation is optional. That is, in some embodiments, process 210 may proceed directly to operation 214 after operation 212. Purge of the chamber may include flowing an inert gas such as Ar, N2, or He into the chamber.

[0033] In one embodiment, process 210 may proceed to operation 214, which includes supplying an oxidant into a vacuum chamber. In one embodiment, the oxidant reacts with a metal precursor to form a metal oxo film on the substrate. In one embodiment, the oxidant in operation 214 is substantially the same as the oxidant in operation 103 and will not be repeated here.

[0034] In one embodiment, process 210 may proceed to operation 215, which includes purging the vacuum chamber. In one embodiment, the purging operation is optional. That is, in some embodiments, process 210 may proceed directly to operation 216 after operation 214. Purge of the chamber may include flowing an inert gas such as Ar, N2, or He into the chamber.

[0035] In one embodiment, process 210 may proceed to operation 216, which includes determining whether a predetermined number of deposition cycles have been completed. Each deposition cycle may refer to an iteration of operations 212-215. If a predetermined number of deposition cycles have not been completed, process 210 loops back to operation 212 and starts a new deposition cycle. Once a predetermined number of deposition cycles have been completed, process 210 proceeds to operation 217.

[0036] In one embodiment, operation 217 includes treating the metal oxo film with plasma. In one embodiment, the plasma treatment may include plasma generated from one or more inert gases such as Ar, N2, and He. In one embodiment, the inert gas or gas may be mixed with one or more oxygen-containing gases such as O2, CO2, CO, NO, NO2, and H2O. In one embodiment, the vacuum chamber may be purged after operation 217. The purging may include pulses of the inert gas such as Ar, N2, and He.

[0037] After operation 217, process 210 may proceed to operation 218. Operation 218 may include determining whether the desired thickness of the metal oxo film has been reached. If the desired thickness has not been reached, the operation may be looped back to 212 to continue processing. If the desired thickness has been reached, the processing proceeds to operation 219, where process 210 ends. In such cases, the final plasma treatment of operation 217 may be considered “post-processing”. In some embodiments, process 210 may end before any post-processing is performed.

[0038] In some embodiments, the plasma treatment operation 217 is performed periodically after a predetermined number of deposition cycles. For example, the plasma treatment operation 217 may be performed every 10 deposition cycles. In other embodiments, the predetermined number of deposition cycles between plasma treatment operations 217 may vary. For example, the first plasma treatment operation 217 may be performed after 10 deposition cycles, and the second plasma treatment operation 217 may be performed after a further 20 deposition cycles.

[0039] Similar to process 100, process 210 may be carried out as a thermal process or a plasma-enhanced process. For example, the plasma may be ignited during one or more of operations 212–215. Furthermore, it should be understood that while the deposition cycle (i.e., operations 212–215) begins with flowing a metal precursor, the deposition cycle may optionally begin with flowing an oxidant.

[0040] In one embodiment, the vacuum chamber used in process 210 may be any suitable chamber capable of providing sub-atmospheric pressure. In one embodiment, the vacuum chamber may include temperature control features for controlling the chamber wall temperature and / or the substrate temperature. In one embodiment, the vacuum chamber may further include features for supplying plasma into the chamber. A detailed description of a suitable vacuum chamber is provided in reference to Figure 3 or Figure 5.

[0041] It will be understood that specific processing parameters may be selected during process 210 to improve one or more properties of the metal oxo film. Generally, process conditions may include a showerhead temperature between about -20°C and about 175°C. The pedestal temperature may further be between about -20°C and about 175°C. In one embodiment, the pressure in the chamber may be less than about 10T. In other embodiments, the pressure may be between about 0.01T and about 10T. The distance between the substrate and the showerhead may be between about 100 mil and about 4,000 mil. With respect to gas flow, the precursor gas may have a flow rate between about 0.1 slm and about 5 slm. The precursor flow rate may include a carrier gas (e.g., Ar or N2). The oxidant (e.g., H2O) flow rate may be between about 50 mgm and about 500 mgm. A carrier gas (e.g., Ar or N2) may be used to transport the oxidant into the chamber. The carrier gas can have a flow rate between approximately 0.01 slm and approximately 5 slm.

[0042] In yet another embodiment, a deposition process utilizing multiple metal precursors is used. The first metal precursor may have the general formula MRxL4-X. The first metal precursor may be substantially similar to the metal precursor described above. The second metal precursor may have the general formula ML4, where L is an alkylamine. That is, the second metal precursor may not contain a carbon-containing R group. Thus, adjustment between the first and second metal precursors can be used to adjust the amount of carbon in the film.

[0043] In one embodiment, the deposition process can utilize a loop comprising a first cycle and a second cycle. The first cycle comprises flowing a first metal precursor, followed by flowing an oxidant. The first cycle may be repeated any number of times. The loop may then proceed to a second cycle comprising flowing a second metal precursor, followed by flowing an oxidant. The second cycle may also be repeated any number of times. In one embodiment, the loop can be repeated any number of times to provide a film of a desired thickness. It will be understood that the deposition loop may be initiated by an iteration of the first cycle or an iteration of the second cycle.

[0044] Such deposition processes impart flexibility to the film composition. For example, by using loops that begin with the second cycle (or involve a large number of iterations of the second cycle), a film with a lower carbon concentration can be formed at the interface with the underlying substrate. This can improve adhesion. Furthermore, a compositional gradient of the film can be achieved by gradually changing the number of iterations of the first and second cycles in each loop.

[0045] Referring now to Figure 3, a plan view of a chamber 330 according to one embodiment is shown. In one embodiment, the chamber 330 is controlled according to instructions stored in memory and can perform one or more metal oxo deposition processes. For example, one or more processes such as processes 100 and 210 described above can be performed in the vacuum chamber 330. In one embodiment, the chamber 330 may include a plurality of regions 331A to D. Although four regions 331 are shown, it will be understood that the chamber 330 may include two or more regions 331. In one embodiment, a plurality of substrates 335 are provided in the region 331. The plurality of substrates 335 are rotated through various regions 331 as indicated by the arrows.

[0046] In one embodiment, each region 331 of the chamber 330 plays a role in performing one of the processing operations of the deposition cycle used to form a metal oxophotoresist. For example, a metal precursor may be poured into the chamber in region 331A, purging may be performed in region 331B, an oxidant may be poured into the chamber in region 331C, and purging may be performed in region 331D. In some embodiments, the boundaries between regions 331 may include features for purging. In such embodiments, regions 331A and 331C may supply the metal precursor, and regions 331B and 331D may supply the oxidant. Thus, two deposition cycles may be performed on the substrate 335 for each rotation of the chamber 330.

[0047] Referring now to Figure 4A, a cross-sectional view of a wafer 440 according to one embodiment is shown. The wafer 440 includes a base substrate 441 and a metal oxophotoresist 442 on the base substrate 441. The base substrate 441 may include silicon or other materials used in semiconductor manufacturing. In one embodiment, the metal oxophotoresist 442 can be deposited on the base substrate 441 using the process described above. In one embodiment, the metal oxophotoresist 442 has a uniform composition and uniform thickness. Such embodiments may be provided when each deposition cycle is substantially uniform.

[0048] However, it should be understood that non-uniform material compositions are also possible through the thickness of the metal oxo photoresist 442. An example of such an embodiment is shown in Figure 4B. As shown, an interface layer 443 is provided between the metal oxo photoresist 442 and the base substrate 441. The interface layer 443 may be a metal oxo material adjusted to have improved adhesion strength compared to the metal oxo photoresist 442. In one embodiment, the interface layer 443 may have a thickness of about a few nanometers to several hundred nanometers. The interface layer 443 may be formed by one or more deposition cycles different from the deposition cycles used to form the rest of the metal oxo photoresist 442. For example, various metal precursors and / or various oxidants may be used to form the interface layer 443 and the metal oxo photoresist 442.

[0049] Forming a metal oxo-photoresist film using a gas-phase process as described in the embodiments above offers significant advantages over wet chemical methods. One such advantage is the elimination of wet by-products. In the gas-phase process, waste liquid is eliminated and by-product removal is simplified. Furthermore, the gas-phase process provides a more uniform photoresist layer. In this context, uniformity may refer to uniformity of thickness across the wafer and / or uniformity of the distribution of metal components in the metal oxo film. In particular, ALD and PE-ALD processes have been demonstrated to provide excellent thickness uniformity and component uniformity.

[0050] Furthermore, by using a vapor phase process, the proportion and composition of metal in the photoresist can be finely tuned. The proportion of metal can be changed by increasing or decreasing the flow rate of the metal precursor into the vacuum chamber and / or by changing the pulse length of the metal precursor / oxidant. Using a vapor phase process may further allow for the inclusion of multiple different metals in the metal oxo film. For example, a single pulse flowing two different metal precursors may be used, or alternating pulses of two different metal precursors may be used.

[0051] Furthermore, metal oxophotoresists formed using vapor phase processes have been demonstrated to be more resistant to post-exposure thickness reduction. While not tied to a specific mechanism, this resistance to thickness reduction is thought to be at least partially due to reduced carbon loss during exposure.

[0052] Figure 5 is a schematic diagram of a vacuum chamber configured to carry out vapor deposition of a metal oxophotoresist according to one embodiment of the present disclosure. The vacuum chamber 500 includes a grounded chamber 505. A substrate 510 is loaded through an opening 515 and clamped to a temperature-controlled chuck 520.

[0053] The process gas is supplied from the gas source 544 through the respective mass flow controllers 549 into the chamber 505. In certain embodiments, a gas supply plate 535 distributes process gases such as metal precursors, oxidants, and inert gases. The chamber 505 is exhausted via an exhaust pump 555.

[0054] When RF power is applied during processing of the substrate 510, plasma is formed within the chamber processing area on the substrate 510. A bias power RF generator 525 is connected to a temperature-controlled chuck 520. The bias power RF generator 525 supplies bias power to excite the plasma, if desired. The bias power RF generator 525 may have a low frequency, for example, between about 2 MHz and 60 MHz, and in certain embodiments, a low frequency in the 13.56 MHz band. In certain embodiments, the vacuum chamber 500 includes a third bias power RF generator 526 with a frequency in the about 2 MHz band. The bias power RF generator 526 is connected to an RF matcher 527, similar to the bias power RF generator 525. A source power RF generator 530 is connected to a plasma generating element (e.g., a gas supply plate 535) via a matcher (not shown) to supply source power and excite the plasma. The source RF generator 530 may have a frequency between 100 and 180 MHz, for example, and in certain embodiments, a frequency in the 162 MHz band. Since the diameter of the substrate changes over time, such as 150 mm, 200 mm, 300 mm, etc., it is common practice in the art to standardize the source and bias power of the plasma etching system to match the substrate area.

[0055] The vacuum chamber 500 is controlled by a controller 570. The controller 570 may include a CPU 572, memory 573, and an I / O interface 574. The CPU 572 can execute processing operations within the vacuum chamber 500 according to instructions stored in memory 573. For example, one or more processes, such as processes 100 and 210 described above, may be executed within the vacuum chamber by the controller 570.

[0056] Figure 6 shows a schematic diagram of a machine in an exemplary form called computer system 600, within which a set of instructions may be executed to cause the machine to perform any one or more of the methods described herein. In an alternative embodiment, the machine may be connected to other machines (e.g., network-connected) in a local area network (LAN), intranet, extranet, or internet. The machine may operate in a client / server network environment as a server or client machine, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), tablet PC, set-top box (STB), portable information terminal (PDA), mobile phone, web device, server, network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that specify the operation to be performed by the machine. Furthermore, although only a single machine is shown, the term “machine” may be interpreted to include any collection of machines (e.g., computers) that individually or collectively execute one or more of the methods described herein, one or more of a set of instructions.

[0057] An exemplary computer system 600 includes a processor 602, main memory 604 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM) (synchronous DRAM (SDRAM) or rhombus DRAM (RDRAM), etc.)), static memory 606 (e.g., flash memory, static random access memory (SRAM), MRAM, etc.), and secondary memory 618 (e.g., data storage device), all communicating with each other via a bus 630.

[0058] Processor 602 represents one or more general-purpose processing devices, such as a microprocessor or a central processing unit. More specifically, processor 602 may be a composite instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor implementing another instruction set, or a processor implementing a combination of instruction sets. Processor 602 may also be one or more special-purpose processing devices, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or a network processor. Processor 602 is configured to execute processing logic 626 for performing the operations described herein.

[0059] The computer system 600 may further include a network interface device 608. Furthermore, the computer system 600 may also include a video display unit 610 (e.g., a liquid crystal display (LCD), a light-emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and a signal generation device 616 (e.g., a speaker).

[0060] The secondary memory 618 may include a machine-accessible storage medium (or, more specifically, a computer-readable storage medium) 632 that stores one or more sets of instructions (e.g., software 622) that embody any one or more of the methods or functions described herein. The software 622 may reside entirely or at least partially in the main memory 604 and / or processor 602 while being executed by the computer system 600. The main memory 604 and processor 602 also constitute a machine-readable storage medium. Furthermore, the software 622 may be transmitted and received over the network 620 via the network interface device 608.

[0061] In exemplary embodiments, the machine-accessible storage medium 632 is shown as a single medium, but the term “machine-readable storage medium” should be interpreted to include a single medium or multiple mediums storing one or more sets of instructions (e.g., a centralized or distributed database, and / or associated caches and servers). Furthermore, the term “machine-readable storage medium” should be interpreted to include any medium capable of storing or encoding a set of instructions executed by a machine, which causes the machine to execute any one or more of the methods of the Disclosure. Accordingly, the term “machine-readable storage medium” should be interpreted to include, but not be limited to, solid memory, optical media, and magnetic media.

[0062] According to one embodiment of the present disclosure, a machine-accessible storage medium stores instructions that cause a data processing system to perform a method for forming a metal oxophotoresist on a substrate. The method includes vaporizing a metal precursor into a vacuum chamber and vaporizing an oxidant into a vacuum chamber. The metal precursor and oxidant can be continuously supplied into the vacuum chamber. The reaction between the metal precursor and the oxidant results in the formation of a metal oxophotoresist on the substrate. In some embodiments, the metal oxophotoresist can be processed by plasma treatment.

[0063] Thus, a method for forming a metal oxophotoresist using a gas-phase process is disclosed.

Claims

1. A method for forming a metal oxophotoresist on a substrate, This includes repeating the sedimentation cycle, and each iteration of the sedimentation cycle is a) A step of flowing a metal precursor into a chamber containing the substrate, and b) The step of flowing an oxidant into the chamber. The oxidant and the metal precursor react to form the metal oxophotoresist. The aforementioned metal precursor is of the general formula MR Ｘ L Ｙ It consists of, where X = 1 to 4 and Y = 4 - X, Y > 0, M is a metal, R is a linear alkyl, branched alkyl, or cyclic alkyl, and L is Br, CN, CNO, SCN, or SeCN. The oxidant is water, O ２ A method comprising one or more of ethylene glycol, alcohol, peroxide, and acid.

2. The method according to claim 1, wherein in at least one iteration of the deposition cycle, the chamber is purged between step a) and step b).

3. The method according to claim 1, wherein in at least one iteration of the deposition cycle, the chamber is purged after step b) and before step a) of a continuous deposition cycle.

4. The method according to claim 1, wherein the oxidant comprises two or more components and / or the metal precursor comprises two or more components.

5. The method according to claim 1, wherein a first deposition cycle comprises a first metal precursor, and a second deposition cycle comprises a second metal precursor different from the first metal precursor.

6. The method according to claim 1, wherein a first deposition cycle comprises a first oxidant, and a second deposition cycle comprises a second oxidant different from the first oxidant.

7. The method according to claim 1, wherein step b) is performed before step a).

8. Generating plasma between step a) in one or more iterations of the deposition cycle and step b) in one or more iterations of the deposition cycle. The method according to claim 1, further comprising:

9. The method according to claim 1, wherein step a) is performed in a first region of the chamber, and step b) is performed in a second region of the chamber, the substrate being rotated between the first region of the chamber and the second region of the chamber.

10. The method according to claim 1, wherein M is Sn.

11. The method according to claim 1, wherein the substrate is rotated between different sections of the chamber in order to carry out steps a) and b).

12. A method for forming a metal oxophotoresist on a substrate, This includes repeating the sedimentation cycle, and each iteration of the sedimentation cycle is a) A step of flowing a metal precursor into a chamber containing the substrate, and b) A step of flowing an oxidant into the chamber, wherein the oxidant and the metal precursor react to form the metal oxophotoresist. This includes repeating the deposition cycle, After the first number of iterations of the deposition cycle, the metal oxophotoresist is treated with plasma. Includes, The aforementioned metal precursor is of the general formula MR Ｘ L Ｙ It consists of, where X = 1 to 4 and Y = 4 - X, Y > 0, M is a metal, R is a linear alkyl, branched alkyl, or cyclic alkyl, and L is Br, CN, CNO, SCN, or SeCN. The oxidant is water, O ２ A method comprising one or more of ethylene glycol, alcohol, peroxide, and acid.

13. The method according to claim 12, further comprising treating the substrate with an initial plasma treatment before initiating the first iteration of the deposition cycle.

14. The method according to claim 12, further comprising restarting the deposition cycle iteration after the plasma treatment.

15. The method according to claim 14, further comprising treating the metal oxophotoresist with a second plasma treatment after a second number of iterations of the deposition cycle.

16. The method according to claim 15, wherein the first number of repetitions of the sedimentation cycle is different from the second number of repetitions of the sedimentation cycle.

17. A method for forming a metal oxophotoresist on a substrate, This includes repeating the sedimentation cycle, and each iteration of the sedimentation cycle is a) A step of flowing a metal precursor into a chamber containing the substrate, wherein the metal precursor is of general formula MR Ｘ L Ｙ The process consists of, where X = 1 to 4 and Y = 4 - X, Y > 0, M is a metal, R is a linear alkyl, branched alkyl, or cyclic alkyl, and L is Br, CN, CNO, SCN, or SeCN. b) A step of purging the chamber, c) A step of flowing an oxidant into the chamber, wherein the oxidant reacts with the metal precursor to form the metal oxo photoresist, and the oxidant comprises one or more of water, O ２ , ethylene glycol, alcohol, peroxide, and acid, and a step, and d) The step of purging the chamber. Methods that include...

18. The method according to claim 17, further comprising generating plasma between step a) and step c) in one or more iterations of the deposition cycle.

19. The method according to any one of claims 1, 12, or 17, wherein X = 1 to 3.

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