Tantalum film growth method and apparatus, and quantum chip, quantum computer, computer-readable storage medium, computer device and computer program product

Abstract

The embodiments of the present application provide a tantalum film growth method and apparatus, and a quantum chip, a quantum computer, a computer-readable storage medium, a computer device and a computer program product. The tantalum film growth method comprises: growing a preset metal seed layer on a substrate, wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; and then, at a preset temperature, growing on the preset metal seed layer a tantalum film having a target morphology, wherein the preset temperature is greater than or equal to 300 degrees Celsius.

Description

Tantalum film growth method, device, quantum chip, quantum computer, computer-readable storage medium, computer equipment, and computer program product

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311705143.8 and application date of December 12, 2023, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of quantum technology, and is related to, but not limited to, a tantalum film growth method, device, quantum chip, quantum computer, computer-readable storage medium, computer equipment, and computer program product. Background Art

[0004] Quantum computers utilize quantum superposition states for computation, thus possessing greater computing power than conventional computers. However, quantum superposition states are easily affected by the environment and can revert to a classical state. The time it takes to return from a quantum superposition state to a classical state is called relaxation time. The length of this relaxation time directly affects the computing power of quantum computers. Therefore, one of the key challenges in quantum technology is how to extend this relaxation time.

[0005] Quantum chips, as a key component of quantum computers, are tiny chips used to store and operate quantum bits (qubits). The bits in quantum computers are called qubits. Unlike the bits in classical computers, qubits have more properties and richer states.

[0006] In related technologies, a superconducting metal film can be grown on a substrate and used to prepare a quantum chip. For example, a tantalum film can be grown on a sapphire substrate and used to prepare a quantum chip. However, due to the uncertainty of the morphology of the tantalum film after growth, it will interact with the microwaves in the quantum chip, resulting in higher two-level loss (TLS), shortening the coherence time of the quantum bit, and thus reducing the relaxation time, which reduces the computing power of the quantum computer.

[0007] Summary of the Invention

[0008] The embodiments of the present application provide a tantalum film growth method, device, quantum chip, quantum computer, computer-readable storage medium, computer equipment and computer program product, which can obtain a tantalum film of a target form. The tantalum film of the target form can reduce the two-level loss, increase the coherence time of the quantum bit, and thereby improve the relaxation time, thereby increasing the computing power of the quantum computer.

[0009] The embodiments of this application provide the following technical solutions:

[0010] An embodiment of the present application provides a tantalum film growth method, which is executed by a computer device and includes:

[0011] A preset metal seed layer is grown on a substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; and a tantalum film of a target morphology is grown on the preset metal seed layer at a preset temperature, wherein the preset temperature is greater than or equal to 300 degrees Celsius.

[0012] An embodiment of the present application provides a quantum chip, which includes at least a transition layer and an electrode, wherein the transition layer and the electrode are made of a tantalum film, and the tantalum film is grown using the above-mentioned tantalum film growth method.

[0013] An embodiment of the present application provides a quantum computer, which includes the above-mentioned quantum chip.

[0014] An embodiment of the present application provides a tantalum film growth device, comprising: a first growth unit, configured to grow a preset metal seed layer on a substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; and a second growth unit, configured to grow a tantalum film of a target morphology on the preset metal seed layer at a preset temperature, wherein the preset temperature is greater than or equal to 300 degrees Celsius.

[0015] An embodiment of the present application provides a computer-readable storage medium, which stores a plurality of computer programs. The computer programs are suitable for being loaded by a processor to execute the above-mentioned tantalum film growth method.

[0016] An embodiment of the present application provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor implements the above-mentioned tantalum film growth method when executing the computer program.

[0017] The present invention provides a computer program product, comprising a computer program stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium and executes the computer program to implement the above-mentioned tantalum film growth method.

[0018] In the embodiment of the present application, a predetermined metal seed layer is grown on a substrate; wherein the absolute value of the difference between the lattice constant of the predetermined metal seed layer and the lattice constant of the substrate is greater than a predetermined threshold; then, a tantalum film of a target morphology is grown on the predetermined metal seed layer at a predetermined temperature, wherein the predetermined temperature is greater than or equal to 300 degrees Celsius. In the embodiment of the present application, a predetermined metal seed layer is added to the substrate, so that a tantalum film with a lattice constant close to that of the predetermined metal seed layer can be subsequently grown, rather than a tantalum film with a lattice constant close to that of the substrate, and a high temperature (i.e., a temperature greater than or equal to 300 degrees Celsius) is applied to the predetermined metal seed layer to grow the tantalum film, thereby obtaining a tantalum film of the target morphology. Thus, compared to the solution of directly growing a tantalum film on a sapphire substrate to prepare a quantum chip in the related art, the tantalum film of the target morphology obtained in the embodiment of the present application can reduce the interaction with microwaves in the quantum chip when preparing the quantum chip, thereby reducing the two-level loss, thereby increasing the coherence time of the quantum bit, and further improving the relaxation time, thereby increasing the computing power of the quantum computer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0020] FIG1 is a cross-sectional view of a tantalum film structure provided in an embodiment of the present application.

[0021] FIG2 is a schematic flow chart of the tantalum film growth method provided in an embodiment of the present application.

[0022] FIG3 is an electron microscope image of a tantalum film grown by the tantalum film growth method provided in an embodiment of the present application.

[0023] FIG4 is another electron microscope image of a tantalum film grown by the tantalum film growth method provided in an embodiment of the present application.

[0024] FIG5 is another electron microscope image of the tantalum film grown by the tantalum film growth method provided in an embodiment of the present application.

[0025] FIG6 is an X-ray diffraction pattern of a tantalum film grown by the tantalum film growth method provided in an embodiment of the present application.

[0026] FIG. 7 is another schematic flow chart of the tantalum film growth method provided in an embodiment of the present application.

[0027] FIG8 is another schematic flow chart of the tantalum film growth method provided in an embodiment of the present application.

[0028] FIG9 is a schematic structural diagram of a tantalum film growth device provided in an embodiment of the present application.

[0029] FIG10 is a schematic diagram of the structure of a terminal provided in an embodiment of the present application.

[0030] FIG11 is a schematic diagram of the structure of the server provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of this application.

[0032] It should be noted that in some of the processes described in the specification, claims, and the above-mentioned figures, multiple steps appearing in a specific order are included, but it should be clearly understood that these steps may not be executed in the order in which they appear in this document or may be executed in parallel. The step numbers are only used to distinguish between different steps, and the sequence numbers themselves do not represent any execution order. In addition, descriptions such as "first", "second", or "target" in the embodiments of the present application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0033] Before further explaining the embodiments of the present application in detail, the nouns and terms involved in the embodiments of the present application are first explained. The nouns and terms involved in the embodiments of the present application are subject to the following interpretations:

[0034] Quantum computing: Quantum computing is a computational method designed using the principles of quantum mechanics. The key difference between quantum computing and traditional computing is that it uses quantum bits (qubits) rather than traditional binary bits. Qubits have distinct properties from traditional binary bits, the most important of which is their ability to simultaneously exist in multiple states. Because qubits can represent two states simultaneously, they carry more information. Using the same number of qubits, more data operations can be performed than with classical computing. Therefore, quantum computing significantly increases computer processing speed.

[0035] A qubit is the basic unit of information in quantum computing. While the role of a qubit in quantum computing is similar to that of a bit in traditional computing, its behavior is fundamentally different. While a classical bit is binary and can only store a 0 or 1, a qubit can store a superposition of all possible states—a superposition of states |0> and |1>. This is similar to the "dead" and "alive" states of Schrödinger's cat, which exists in a superposition of both states until the box is opened. Because a qubit can represent two states simultaneously, it carries more information, allowing it to perform more computations on data with the same number of qubits than in classical computing. This significantly increases computer processing speed.

[0036] Quantum bit unit: A storage unit in quantum hardware resources used to hold quantum bits involved in calculations.

[0037] The coherence time of a qubit refers to the length of time a qubit can maintain its quantum state. In quantum mechanics, the quantum coherence of an open quantum system gradually disappears over time due to quantum entanglement with the external environment. This effect is called quantum decoherence, also known as quantum decoherence.

[0038] A two-level energy system is a quantum system consisting of two energy levels. In quantum mechanics, one energy level usually corresponds to one state of the system.

[0039] Second-level loss (TLS loss): refers to the two-level system in the quantum chip material, which shortens the coherence time of the quantum bit due to the interaction with the microwaves in the quantum chip.

[0040] Substrate: This can be a silicon or sapphire substrate. It is one of the fundamental components of a quantum chip, supporting its various functional units and providing structural support. The material and properties of the substrate significantly influence the electrical, thermal, and mechanical properties of the quantum chip.

[0041] Superconducting metal films: such as aluminum films or tantalum films, superconducting metal films are used to manufacture superconducting circuits.

[0042] Seed layer: A thin layer of metal or other material applied to the surface of a material to provide a seed point to promote subsequent material deposition or growth.

[0043] Tantalum film: A thin sheet of tantalum metal used in quantum chips can be used to fabricate transition layers and electrodes. The transition layer improves structural stability, while the electrode provides stable current transmission. Tantalum film exists in two phases: α (alpha) and β (beta). The α phase refers to the body-centered cubic structure of the tantalum film. Its surface exhibits a striped morphology under an electron microscope. The β phase refers to the face-centered cubic structure of the tantalum film. Its surface exhibits a clustered morphology under an electron microscope. It should be noted that the α phase is more suitable for the fabrication of superconducting quantum chips due to its lower TLS loss compared to the β phase. This lower TLS loss is due to the denser oxide layer of the α phase, which prevents contaminants from damaging the substrate surface. It also smoothes uneven surfaces, ensuring proper execution of subsequent processing steps. The oxide layer is a crucial insulating layer in integrated circuits. It effectively isolates interference between different circuits, ensuring the proper operation of the chip circuits. Therefore, α phase tantalum film is more suitable for quantum chips.

[0044] To better illustrate the embodiments of the present application, the following briefly describes the processing of a quantum chip. First, a superconducting metal film (aluminum or tantalum) is formed on a substrate (silicon or sapphire). A uniform layer of photoresist is then applied to the surface of the superconducting metal film. Laser irradiation is then performed on specific areas of the photoresist, as required, to change the properties of the corresponding photoresist. The laser is then rinsed with a developer to dissolve and clean the irradiated photoresist. The next step is to bombard the exposed metal layer, etching the shape of the circuit, and then rinse away the remaining photoresist. The superconducting circuit is then completed.

[0045] After completing the superconducting circuit portion, the next step is to apply two layers of electron beam photoresist to prepare the core component of the quantum chip: the Josephson junction. The Josephson junction is a basic element in superconducting physics. The Josephson junction is a structure formed by two superconductors separated by a very thin insulating layer or semiconductor layer. Electron beam lithography (EBL) can be used to define the Josephson junction area. By evaporating at a specific angle, superconducting metal can be grown only in specific grooves. Between evaporations, oxidation operations can be added to prepare the intermediate oxide layer. In this way, a three-layer Josephson junction is completed. Then, by rinsing with a degumming solution, the excess part is cleaned off, and a quantum chip is completed.

[0046] At present, aluminum film is commonly used as a superconducting metal film to prepare quantum chips. However, with the continuous development of micro-nano processing, tantalum film is increasingly being used as a superconducting metal film to prepare quantum chips. Moreover, because tantalum film has less TLS loss than aluminum film, it can obtain a longer relaxation time, thereby gradually replacing aluminum film as a superconducting metal film.

[0047] During the research and practice of related technologies, the inventors of this application discovered that tantalum films have two forms, α-phase and β-phase, and α-phase tantalum films are more suitable for quantum chips. However, since tantalum films are currently grown directly on substrates, the morphology of the tantalum films after growth is uncertain, resulting in the grown tantalum films producing higher two-level losses, thereby shortening the coherence time of quantum bits, and further reducing the relaxation time, which reduces the computing power of quantum computers.

[0048] In order to solve the above-mentioned problems, the embodiment of the present application proposes a technology capable of growing high-purity α-phase tantalum film. Please refer to Figure 1. Figure 1 is a cross-sectional view of the tantalum film structure provided in the embodiment of the present application. In the embodiment of the present application, the tantalum film structure includes a substrate 101, a preset metal seed layer 102 and a tantalum film 103. That is, the embodiment of the present application adds a preset metal seed layer 102 before growing the tantalum film 103 on the substrate 101, and applies a certain high temperature (greater than or equal to 300 degrees Celsius) when growing the tantalum film, so as to obtain a high-purity α-phase tantalum film (the purity of the α-phase tantalum film is greater than the purity threshold), thereby reducing the two-level loss, increasing the coherence time of the quantum bit, and then increasing the relaxation time, so as to improve the computing power of the quantum computer. Please continue to refer to the following embodiments for the specific implementation process.

[0049] In this embodiment, the description will be made from the perspective of a tantalum film growth device. The tantalum film growth device can be integrated into a computer device having a storage unit and a microprocessor installed and having computing capabilities. The computer device can be a terminal or a server, and it should be noted that the computer device can control the corresponding vacuum electron beam coating machine to perform coating operations.

[0050] Please refer to FIG2 , which is a schematic flow diagram of a tantalum film growth method provided in an embodiment of the present application. The tantalum film growth method includes:

[0051] In step 201 , a predetermined metal seed layer is grown on a substrate.

[0052] The substrate can be a sapphire substrate or a silicon substrate. Sapphire is a material used for chip substrates. Sapphire offers excellent stability and can be used in high-temperature growth processes. It also has high mechanical strength and is easy to handle and clean. Therefore, most processes generally use sapphire as the substrate. Silicon is an electronic-grade silicon material and one of the key materials for manufacturing semiconductor devices. It is commonly used for growing crystals and preparing thyristor devices. Due to its unique electrical and mechanical properties, silicon substrates are widely used in fields such as integrated circuits and solar cells. The main characteristics of silicon substrates are high-temperature stability, mechanical strength, and optical transparency. At high temperatures, silicon substrates do not experience problems such as expansion and thermal deformation, maintaining extremely high stability. Silicon substrates also have excellent mechanical strength and can withstand significant pressure and extrusion. In the embodiments of this application, a silicon substrate is used as an example, as silicon substrates have better compatibility than sapphire substrates.

[0053] The preset metal in the preset metal seed layer may be niobium or chromium, that is, the preset metal seed layer is a niobium seed layer or a chromium seed layer.

[0054] In order to better understand the embodiments of the present application, the lattice constant is first explained. The lattice constant, or lattice constant, refers to the side length of the unit cell, that is, the side length of each parallelepiped unit. The lattice constant is an important basic parameter of the crystal structure. It should be noted that the substrate, the preset metal seed layer and the tantalum film all have lattice constants. For example, when the substrate is a silicon substrate, the lattice constant of the silicon substrate is 0.543nm (nanometer), when the preset metal seed layer is a niobium seed layer, the lattice constant of the niobium seed layer is 0.447nm, and when the preset metal seed layer is a chromium seed layer, the lattice constant of the chromium seed layer is 0.2884nm. Correspondingly, the tantalum film has two forms, α-phase and β-phase. The lattice constant of the α-phase tantalum film is 0.384nm, and the lattice constant of the β-phase tantalum film is 0.531nm.

[0055] In the related art, when growing tantalum film, the atoms of the tantalum film must correspond one-to-one with the atoms of the grown layer. From the above comparison, it can be seen that since the lattice constant of the silicon substrate, 0.543nm, is closer to the lattice constant of the β-phase tantalum film, 0.531nm, and is quite different from the lattice constant of the α-phase tantalum film, 0.384nm, that is, the absolute value of the difference between the lattice constant of the silicon substrate, 0.543nm, and the lattice constant of the β-phase tantalum film, 0.531nm, is 0.012nm, and the absolute value of the difference between the lattice constant of the silicon substrate, 0.543nm, and the lattice constant of the α-phase tantalum film, 0.384nm, is 0.15nm. 0.012nm is less than 0.15nm. Therefore, assuming that the tantalum film is grown directly on the silicon substrate, it is easy to grow the β-phase tantalum film (that is, the growth method of the related art).

[0056] In order to better illustrate the embodiments of the present application, please refer to Figure 3. Figure 3 is an electron microscope image of the tantalum film grown by the tantalum film growth method provided in the embodiments of the present application. The electron microscope image 1 of the tantalum film is an electron microscope schematic diagram of the tantalum film obtained after growing the tantalum film directly on the silicon substrate. It can be seen that the tantalum film electron microscope image 1 shows a clustered morphology, which means that the tantalum film is grown directly on the silicon substrate, and the β-phase tantalum film will cause the subsequently processed quantum chip to have higher two-level loss, shorten the coherence time of the quantum bit, and then lead to a decrease in the relaxation time, which reduces the computing power of the quantum computer.

[0057] Since the lattice constant of the preset metal seed layer is closer to the lattice constant of the α-phase tantalum film, but has a large difference with the lattice constant of the β-phase tantalum film, that is, the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the α-phase tantalum film is smaller than the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the β-phase tantalum film. For example, the lattice constant of the niobium seed layer is 0.447nm, which is closer to the lattice constant of the α-phase tantalum film, 0.384nm, and has a large difference with the lattice constant of the β-phase tantalum film, 0.531nm. The lattice constant of the chromium seed layer is 0.2884nm, which is closer to the lattice constant of the α-phase tantalum film, 0.384nm, and has a large difference with the lattice constant of the β-phase tantalum film, 0.531nm. Therefore, assuming that a tantalum film is grown on the preset metal seed layer, the α-phase tantalum film is easily grown. Since the α-phase tantalum film is more suitable for quantum chips, in order to obtain the α-phase tantalum film in the embodiment of the present application, the corresponding preset metal seed layer can be first grown on the substrate. The absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold, that is, the lattice constant of the preset metal seed layer needs to be closer to the lattice constant of the α-phase tantalum film, and the lattice constant of the substrate is closer to the lattice constant of the β-phase tantalum film. Therefore, the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate will be greater than a certain threshold, that is, the preset threshold. The preset threshold is the critical value for defining the difference. For example, the preset threshold can be 0.6nm or 0.7nm. The specific value is mainly based on the actual processing scenario, and the example here is not a specific limitation.

[0058] In some embodiments, taking the preset metal seed layer as a niobium seed layer as an example, growing a corresponding preset metal seed layer on a substrate may include: growing a preset metal seed layer of a first preset thickness on the substrate through a first preset coating power, a first preset argon flow rate, and a first preset target-substrate distance.

[0059] It should be noted that in thin film technology, coating is a process of forming a film layer by depositing materials on a substrate, and coating power refers to the energy input used in this process, that is, the coating power is the power of the coating machine, and the unit is watt (W). In the embodiment of the present application, the coating power refers to the power used to heat, evaporate or plasma excite the niobium seed during the coating process. The coating power can be in the form of direct current (DC) or radio frequency (RF). The argon flow rate is the specific value of the flow rate when argon is used as the protective gas, and the unit is standard cubic centimeter per minute (sccm). When growing a preset metal seed layer in the embodiment of the present application, argon is used as the protective gas, and multi-arc ion plating is used for coating. Multi-arc ion plating (AIP) is a thin film preparation technology. AIP combines the principles of evaporation and sputtering, and deposits metal films or alloy films on the substrate surface through arc discharge and ion bombardment. During multi-arc ion plating, an arc discharge generates high temperatures between a target (e.g., a niobium seed material) and a cathode, causing atoms on the target surface to evaporate. Ion bombardment accelerates the evaporated atoms under the action of an electric field and converts them into ions. When these ions strike the substrate, their kinetic energy allows them to penetrate beneath the substrate surface, forming a thin film. The ions deposit on the substrate to form a thin film, while simultaneously being affected by the electric field on the target surface, resulting in a thin film with a good crystalline structure and surface quality. Multi-arc ion plating typically achieves higher deposition rates than traditional evaporation or sputtering techniques. Furthermore, due to the ion bombardment, the film adheres very well to the substrate, resulting in a thin film with good uniformity, a good crystalline structure, and low surface roughness. Multi-arc ion plating equipment typically includes a vacuum chamber, target, cathode, power supply, and control system. Multi-arc ion plating technology allows for adjustment of parameters such as target-substrate distance, power, and gas flow rate to optimize film performance.

[0060] The target-substrate distance refers to the distance between the target material and the base (i.e., the substrate). The size of the target-substrate distance affects multi-arc ion plating in two main ways. First, the size of the target-substrate distance affects the energy and angle of the ion beam in the multi-arc ion plating process. When the target-substrate distance is small (for example, the target-substrate distance is less than a preset distance threshold), the energy and angle of the ion beam will be more concentrated, which can make the composition and structure of the film more uniform. When the target-substrate distance is large (for example, the target-substrate distance is greater than or equal to the preset distance threshold), the energy and angle of the ion beam will be more dispersed, which can easily lead to uneven composition and structure of the film, thereby affecting the quality and performance of the film.

[0061] Thus, in the embodiment of the present application, the first preset coating power is a coating power that is manually preset to achieve stable growth of a preset metal seed layer, for example, it can be 190 watts, the first preset argon flow rate is a manually preset argon flow rate that is manually preset to achieve stable growth of a preset metal seed layer, for example, it can be 2.5 standard cubic centimeters per minute, the first preset target-substrate distance is a manually preset target-substrate distance that is manually preset to achieve stable growth of a preset metal seed layer, for example, it can be 100 mm (millimeter), and the first preset thickness is the thickness of a stably generated preset metal seed layer, for example, it can be 2 nm. Thus, a preset metal seed layer of a stable first preset thickness can be grown on a substrate by using the first preset coating power, the first preset argon flow rate, and the first preset target-substrate distance. For example, a preset metal seed layer of a stable first preset thickness of 2 nm can be grown by using a first preset coating power of 190 watts, a first preset argon flow rate of 2.5 standard cubic centimeters per minute, and a first preset target-substrate distance of 100 mm.

[0062] In step 202 , a tantalum film of a target morphology is grown on a predetermined metal seed layer at a predetermined temperature.

[0063] Among them, since the lattice constant of the preset metal seed layer is closer to the lattice constant of the α-phase tantalum film, and has a large difference with the lattice constant of the β-phase tantalum film, the lattice constant of the tantalum film grown on the preset metal seed layer will be close to the lattice constant of the preset metal seed layer, that is, it is easier to generate an α-phase tantalum film. For example, the lattice constant of the niobium seed layer is 0.447nm, which is closer to the lattice constant of the α-phase tantalum film, and has a large difference with the lattice constant of the β-phase tantalum film, which is 0.531nm. That is, the absolute value of the difference between the lattice constant of the niobium seed layer, 0.447nm, and the lattice constant of the α-phase tantalum film, 0.384nm, is smaller than the absolute value of the difference between the lattice constant of the niobium seed layer, 0.447nm, and the lattice constant of the β-phase tantalum film, 0.531nm. The lattice constant of the chromium seed layer is 0.2884nm, which is closer to the lattice constant of the α-phase tantalum film, 0.384nm. The lattice constant of the α-phase tantalum film is closer to 0.384nm, but is greatly different from the lattice constant of the β-phase tantalum film of 0.531nm. That is, the absolute value of the difference between the lattice constant of the chromium seed layer of 0.2884nm and the lattice constant of the α-phase tantalum film of 0.384nm is smaller than the absolute value of the difference between the lattice constant of the chromium seed layer of 0.2884nm and the lattice constant of the β-phase tantalum film of 0.531nm. Therefore, it is easier to grow an α-phase tantalum film regardless of whether the tantalum film is grown on the niobium seed layer or the chromium seed layer.

[0064] In order to better illustrate the embodiments of the present application, please refer to Figure 4. Figure 4 is another electron microscope image of the tantalum film grown by the tantalum film growth method provided in the embodiments of the present application. The electron microscope image 2 of the tantalum film is an electron microscope image after the tantalum film is grown on the preset metal seed layer at room temperature. The indoor temperature is the temperature of the current indoor environment, generally between 20 degrees Celsius and 30 degrees Celsius. It can be seen that most of the tantalum film in the electron microscope image 2 has a strip morphology, but there is still a small amount of cluster morphology 21, which means that the tantalum film grown on the preset metal seed layer is not a very pure α-phase tantalum film, and some β-phase tantalum film is still doped in it.

[0065] It should be noted that α-phase tantalum film and β-phase tantalum film refer to two different crystal structures of the metallic element tantalum in thin film form. Tantalum is a transition metal with a high melting point and excellent chemical stability. The crystal structure of tantalum film has a decisive influence on its performance. α-phase tantalum film has a hexagonal close-packed (HCP) structure. This structure gives α-phase tantalum film high hardness and excellent mechanical properties. α-phase tantalum film generally exhibits good corrosion and wear resistance, making it suitable for applications requiring high hardness and corrosion resistance. β-phase tantalum film has a body-centered cubic (BCC) structure. Compared to α-phase tantalum film, β-phase tantalum film is generally stable at higher temperatures. β-phase tantalum film can have different physical and chemical properties, such as lower hardness and different corrosion resistance. In some cases, β-phase tantalum film may exhibit better ductility. Under certain conditions, a phase transition can occur between α-phase and β-phase tantalum films. This phase transition can be affected by temperature, pressure, and the chemical environment. Understanding and controlling this phase transformation is crucial to achieving the desired tantalum film properties.

[0066] The present embodiment illustrates the effect of temperature on this phase transition. The α-phase tantalum film is a stable structure, while the β-phase tantalum film is a metastable structure. The relationship between the stable and metastable structures is as follows: Both states are states of matter. The stable structure has the lowest energy and is thermodynamically most stable compared to the metastable structure; the metastable structure has higher energy and is thermodynamically unstable compared to the stable structure. The α-phase tantalum film is thermodynamically stable, while the β-phase tantalum film is thermodynamically unstable. This means that the present embodiment can apply a high temperature during the tantalum film growth process, causing a portion of the metastable structure of the β-phase tantalum film to cross the barrier layer and reach the stable structure of the α-phase tantalum film, thereby transforming the β-phase tantalum film into the α-phase tantalum film. Therefore, the present embodiment can set a preset temperature, which is a temperature of not less than 300 degrees Celsius, for example, 400 degrees Celsius. This can be understood as a high temperature of not less than 300 degrees Celsius. It is easy to understand that this preset temperature cannot be too high, otherwise it will destroy the atomic structure of the tantalum film. Therefore, an upper limit for the preset temperature can also be set, which can generally be 500 degrees Celsius. In this way, when growing a tantalum film on a preset metal seed layer, a high temperature of the preset temperature is applied to obtain a tantalum film of a target form, that is, a high-purity α-phase tantalum film, referred to as an α-phase tantalum film. In this way, the quantum chip processed with the tantalum film of the target form can avoid the generation of high two-level loss, increase the coherence time of the quantum bit, improve the relaxation time, and enhance the computing power of the quantum computer.

[0067] In some embodiments, growing a tantalum film of a target shape on the preset metal seed layer at a preset temperature can be achieved in the following manner: growing a tantalum film of a target shape of a second preset thickness on the preset metal seed layer at a second preset coating power, a second preset argon flow rate, a second preset target-substrate distance, and a preset temperature.

[0068] In an embodiment of the present application, the second preset coating power is a manually preset coating power for achieving stable growth of a tantalum film of a target morphology, and may be, for example, 170 watts. The second preset argon gas flow rate is a manually preset argon gas flow rate for achieving stable growth of a tantalum film of a target morphology, and may be, for example, 10 standard cubic centimeters per minute. The second preset target-substrate distance is a manually preset target-substrate distance for achieving stable growth of a tantalum film of a target morphology, and may be, for example, 100 mm (millimeter). The second preset thickness is a manually preset thickness of the grown tantalum film of a target morphology, and may be, for example, 200 nm. The preset temperature is a manually preset temperature for achieving growth of a high-purity tantalum film of a target morphology, and may be, for example, a high temperature between 300 and 500 degrees Celsius. The upper limit of 500 degrees Celsius is imposed to avoid damage to the tantalum film structure if temperatures exceed 500 degrees Celsius. Thus, a stable, high-purity tantalum film of a target morphology of a second preset thickness can be grown on the preset metal seed layer using the second preset coating power, the second preset argon gas flow rate, the second preset target-substrate distance, and the preset temperature. For example, a stable and high-purity tantalum film with a target morphology of a second preset thickness of 200 nm can be grown by using a second preset coating power of 170 watts, a second preset argon flow rate of 10 standard cubic centimeters per minute, a second preset target-substrate distance of 100 mm, and a preset temperature of 400 degrees Celsius.

[0069] To better illustrate the embodiments of the present application, please refer to FIG5 , which is another electron microscope image of the tantalum film grown by the tantalum film growth method provided in the embodiments of the present application. The electron microscope image 3 of the tantalum film is a schematic electron microscope image after the tantalum film is grown on the preset metal seed layer at a preset temperature. It can be seen that the tantalum film in the electron microscope image 3 basically has all shown a stripe morphology, which means that the tantalum film is grown on the preset metal seed layer at a preset temperature, and a very high purity (i.e., the purity is greater than the preset purity threshold, for example, the purity threshold can be 98%) α-phase tantalum film is obtained. In this way, the corresponding quantum chip is made based on the tantalum film of the target morphology, which can avoid the generation of high two-level loss, thereby increasing the coherence time of the quantum bit, improving the relaxation time, and improving the computing power of the quantum computer.

[0070] In some embodiments, even if it is possible to determine whether the tantalum film is a very pure α-phase tantalum film from the electron microscope image, there may be a situation where the α-phase tantalum film is unevenly distributed, resulting in a large difference between the area captured by the electron microscope image and other areas, resulting in an inaccurate judgment result. Alternatively, the judgment result may be inaccurate due to inaccurate imaging during electron microscope observation. In order to achieve a more accurate purity determination of the α-phase tantalum film, it can also be detected by X-ray diffraction (XRD) measurement. That is, after growing a tantalum film on the preset metal seed layer at a preset temperature, it can be further combined with XRD detection technology to determine whether the generated tantalum film is a tantalum film of the target form.

[0071] In an embodiment of the present application, when combining XRD detection technology to determine whether the generated tantalum film is a tantalum film of the target morphology, an X-ray diffraction measurement can be performed on the tantalum film to obtain an X-ray diffraction measurement result, and the X-ray diffraction measurement result includes: the intensity of the X-rays reflected back by the tantalum film at different diffraction angles. Then, based on the X-ray diffraction measurement result, it is determined that the tantalum film grown on the preset metal seed layer is a tantalum film of the target morphology. In the implementation process, based on the X-ray diffraction measurement result, it is determined that the tantalum film grown on the preset metal seed layer is a tantalum film of the target morphology. It can be that among the intensities of the X-rays reflected back at different diffraction angles, when it is detected that the intensity of the X-rays reflected back at the first preset diffraction angle is the largest, the morphology of the tantalum film is determined to be the target morphology.

[0072] Here, X-ray diffraction refers to a research method that uses X-ray diffraction to analyze the diffraction pattern of a material to obtain information such as the material's composition, the structure or morphology of the atoms or molecules within the material. X-ray diffraction uses X-rays to irradiate a crystal and analyze the diffraction pattern produced by the interaction between the X-rays and the crystal to study the atomic arrangement within the crystal, thereby determining the crystal structure. The crystal structure causes the incident X-ray beam to diffract in many specific directions. By measuring the angles of these diffracted beams and the intensity of the reflected X-rays, a three-dimensional image of the electron density within the crystal can be generated (i.e., the crystal morphology can be determined). X-ray intensity refers to the energy of X-ray radiation that passes through a unit area per unit time. It is usually expressed as the amount of radiation per unit area (dose), with the unit being Gray (Gy). X-rays are a type of electromagnetic radiation with a very short wavelength (usually between 0.01 and 10 nanometers), which allows them to penetrate matter and reveal its internal structure. Diffraction occurs when X-rays strike a crystal. The atoms in the lattice scatter the X-rays like a small light source. Due to the periodic arrangement of atoms in the lattice, these scattered X-ray waves interfere, forming a diffraction pattern in a specific direction. The position of the diffraction pattern can be described by Bragg's law: 2d*sinθ=nλ, where d is the lattice spacing, θ is the angle between the incident X-ray and the lattice plane, n is the diffraction order, and λ is the wavelength of the X-ray.

[0073] In the embodiment of the present application, a preset temperature of 400 degrees Celsius is used as an example for explanation. A corresponding tantalum film is grown on the preset metal seed layer at 400 degrees Celsius. Accordingly, in order to determine whether the tantalum film is a high-purity α-phase tantalum film, the tantalum film can be subjected to XRD measurement, that is, the tantalum film is tested by X-rays at different diffraction angles. The diffraction angle refers to the angle formed by the X-rays and the upper surface of the substrate. Here, the upper surface of the substrate refers to the surface of the substrate near the preset metal seed layer. It should be noted that the α-phase tantalum film has a body-centered cubic structure. The body-centered cubic structure of the α-phase tantalum film maximizes the intensity of the X-rays reflected back from the α-phase tantalum film at a diffraction angle of 38.23 degrees. This 38.23 degrees is the first preset diffraction angle in the embodiment of the present application. Accordingly, the β-phase tantalum film has a face-centered cubic structure. The face-centered cubic structure of the β-phase tantalum film maximizes the intensity of the X-rays reflected back from the β-phase tantalum film at a diffraction angle of 33.7 degrees. Based on this, the intensity of the X-rays reflected back at the first preset diffraction angle can be detected to see whether it is the largest among the intensities of the X-rays reflected back at different diffraction angles, so as to determine whether the tantalum film is a high-purity α-phase tantalum film. When it is detected that the intensity of the X-rays reflected back at the first preset diffraction angle is the largest, it indicates that the morphology of the tantalum film is the target morphology, that is, the morphology of the tantalum film is a high-purity α-phase tantalum film.

[0074] To better illustrate the embodiments of the present application, please refer to Figure 6, which is an X-ray diffraction pattern of the tantalum film grown by the tantalum film growth method provided in the embodiments of the present application. In the X-ray diffraction pattern, the horizontal axis is the angle between the X-ray and the upper surface of the substrate (i.e., the diffraction angle), and the vertical axis is the intensity of the reflected X-ray detected by the detector. It can be seen from the X-ray diffraction pattern that at 38.23°, the intensity of the reflected X-ray is the largest, which indicates that the grown tantalum film is a high-purity α-phase tantalum film.

[0075] In some embodiments, since the preset temperature represents a high temperature, the value range may be between [300, 500] degrees Celsius, which means that there may be multiple preset temperatures, that is, the metastable structure of the β-phase tantalum film may cross the barrier layer to reach the stable structure of the α-phase tantalum film through the high temperature of the multiple preset temperatures. It should be noted that at different preset temperatures, the efficiency of the metastable structure of the β-phase tantalum film crossing the barrier layer to reach the α-phase tantalum film is different. Therefore, in order to achieve the highest purity α-phase tantalum film, the temperature at which the metastable structure of the β-phase tantalum film crosses the barrier layer to reach the α-phase tantalum film can be obtained by testing between [300, 500] degrees Celsius. As shown in FIG7 , the testing process is as follows:

[0076] In step 203 , a test predetermined metal seed layer is grown on a test substrate.

[0077] The test substrate and the aforementioned substrate are made of the same material, that is, they can be silicon substrates. The test preset metal seed layer and the aforementioned preset metal seed layer are made of the same material, that is, the preset metal can be niobium or chromium, so that the corresponding test preset metal seed layer can be first grown on the test substrate. The absolute value of the difference between the lattice constant of the test preset metal seed layer and the lattice constant of the test substrate is also greater than the preset threshold, that is, the lattice constant of the test preset metal seed layer needs to be closer to the lattice constant of the α-phase tantalum film, and the lattice constant of the test substrate is closer to the lattice constant of the β-phase tantalum film. Therefore, the difference between the lattice constant of the test preset metal seed layer and the lattice constant of the test substrate will be greater than a certain threshold, that is, the preset threshold. The preset threshold is the critical value for defining the difference, which can be 0.6nm or 0.7nm.

[0078] In step 204 , different test temperatures are selected in sequence from the target temperature range; and different test tantalum films are grown on the test preset metal seed layer at the different test temperatures.

[0079] In some embodiments, the target temperature range is between [300, 500] degrees Celsius. In order to implement the test and select the most appropriate preset temperature, it is necessary to select different test temperatures from the target temperature range in sequence, that is, starting from 300 degrees Celsius, select multiple different test temperatures in sequence.

[0080] In one implementation, the test temperature may be selected in an arithmetic progression, for example, 300 degrees Celsius, 310 degrees Celsius, 320 degrees Celsius, 330 degrees Celsius, 340 degrees Celsius, ... 500 degrees Celsius may be selected as the test temperature.

[0081] In another implementation, multiple test temperatures may be randomly selected from the target temperature range, for example, 300 degrees Celsius, 380 degrees Celsius, 400 degrees Celsius, 415 degrees Celsius, 470 degrees Celsius, and 500 degrees Celsius may be randomly selected as test temperatures.

[0082] There are multiple test temperatures, and the number of test temperatures can be determined based on factors such as test conditions and test efficiency. For example, when the test conditions are multiple multi-arc ion plating equipment and multiple X-ray diffractometers, and the test efficiency is high, it can be determined that the number of test temperatures is greater than the quantity threshold, that is, more test temperatures can be selected for testing. After determining the number of test temperatures, the selection method of the test temperatures can also be determined. The selection method of the test temperatures includes the above-mentioned arithmetic progression selection method and random selection method. After determining the number of test temperatures and the selection method of the test temperatures, the number of test temperatures is selected from the target temperature range according to the number and selection method, and the selected test temperatures are further used for testing.

[0083] Here, we use the selection method in the form of an arithmetic progression as an example to illustrate that 300 degrees Celsius, 301 degrees Celsius, and so on can be selected as the test temperature in sequence until 500 degrees Celsius is selected as the test temperature. There are 201 test temperatures. On this basis, at each test temperature, a test tantalum film corresponding to a different test temperature can be grown on a test preset metal seed layer. That is, 201 test substrates need to be prepared, and a corresponding test preset metal seed layer is grown on each set of test substrates. Then, at each test temperature, a test tantalum film corresponding to a different test temperature is grown on the test preset metal seed layer grown on each test substrate, thereby obtaining 201 test tantalum films.

[0084] In step 205 , an X-ray diffraction measurement is performed on each test tantalum film according to a first preset diffraction angle to obtain a test intensity of X-rays reflected back by each test tantalum film at the first preset diffraction angle.

[0085] In step 206 , the test temperature corresponding to the test tantalum film with the highest test intensity is determined as the preset temperature.

[0086] It is easy to understand that at different test temperatures, the efficiency of the metastable structure of the β-phase tantalum film crossing the barrier layer to reach the α-phase tantalum film is different. Therefore, 201 test tantalum films can be tested. For example, X-ray diffraction measurements can be performed on each test tantalum film according to a first preset diffraction angle of 38.23 degrees to obtain the test intensity of the X-rays reflected back from each test tantalum film at the first preset diffraction angle. It should be noted that since the test intensity of the X-rays reflected back at the diffraction angle of 38.23 degrees represents the purity of the α-phase tantalum film, the higher the purity of the α-phase tantalum film, the greater the test intensity of the X-rays reflected back at the diffraction angle of 38.23 degrees.

[0087] Therefore, the test tantalum film with the highest test intensity can be regarded as the α-phase tantalum film with the highest purity. The test temperature of the test tantalum film with the highest test intensity is the most suitable preset temperature. For example, when the test temperature is 400 degrees Celsius, the test intensity of the tantalum film is the highest. Therefore, 400 degrees Celsius can be used as the preset temperature. In this way, in actual quantum chip production, the highest purity α-phase tantalum film can be grown on the preset metal seed layer at the most suitable preset temperature. This can avoid the high two-level loss in the quantum chip obtained by subsequent processing, increase the coherence time of the quantum bit, improve the relaxation time, and thus enhance the computing power of the quantum computer.

[0088] As can be seen from the above, the embodiment of the present application grows a corresponding preset metal seed layer on a substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; and a tantalum film of a target morphology is grown on the preset metal seed layer at a preset temperature, wherein the preset temperature is not less than 300 degrees Celsius. In this way, by adding a layer of preset metal seed layer to the substrate, a tantalum film with a lattice constant close to that of the preset metal seed layer can be subsequently grown, rather than a tantalum film with a lattice constant close to that of the substrate. The tantalum film is then grown at a high temperature on the preset metal seed layer to obtain a tantalum film of the target morphology. Compared to the solution of directly growing a tantalum film on a sapphire substrate to prepare a quantum chip in the related art, the tantalum film of the target morphology obtained in the embodiment of the present application can reduce the interaction with microwaves in the quantum chip, thereby reducing two-level loss, increasing the coherence time of the quantum bit, and thereby improving the relaxation time, thereby increasing the computing power of the quantum computer.

[0089] In combination with the method described in the above embodiment, the following examples are given to further illustrate the method in detail.

[0090] In this embodiment, the tantalum film growth device is integrated into a computer device, and the tantalum film growth method is executed by the computer device as an example for explanation. The computer device can control the corresponding multi-arc ion plating equipment or vacuum electron beam coating machine to perform the plating operation.

[0091] To better illustrate the embodiment of the present application, please refer to FIG8 , which is another flow chart of the tantalum film growth method provided in the embodiment of the present application.

[0092] In step 301, a test preset metal seed layer is grown on a test substrate, different test temperatures are selected in sequence from a target temperature range, and test tantalum films corresponding to different test temperatures are grown on the test preset metal seed layer.

[0093] Here, taking a silicon substrate as the test substrate and a niobium seed layer as the test preset metal seed layer as an example, a corresponding test niobium seed layer can be first grown on the test silicon substrate. The lattice constant of the test silicon substrate is 0.543 nm, the lattice constant of the test niobium seed layer is 0.447 nm, and the tantalum film has two morphologies, α-phase and β-phase, with the lattice constant of the α-phase tantalum film being 0.384 nm and the lattice constant of the β-phase tantalum film being 0.531 nm. That is, the lattice constant of the test niobium seed layer is closer to that of the α-phase tantalum film, while the lattice constant of the test silicon substrate is closer to that of the β-phase tantalum film. Therefore, the difference between the lattice constant of the test niobium seed layer and the lattice constant of the test silicon substrate is greater than a certain threshold, namely a preset threshold. The preset threshold is the critical value that defines the difference, which can be 0.6 nm or 0.7 nm.

[0094] The target temperature range is [300, 500] degrees Celsius. To perform the test, the most appropriate preset temperature needs to be selected. Different test temperatures can be selected from the target temperature range, starting from 300 degrees Celsius, and then selecting 300 degrees Celsius, 301 degrees Celsius, and so on as test temperatures, until 500 degrees Celsius is selected as the test temperature. There are 201 test temperatures.

[0095] On this basis, a corresponding test tantalum film can be grown on the test niobium seed layer at each test temperature. That is, test tantalum films at different test temperatures can be grown on the test niobium seed layer. Therefore, 201 test silicon substrates are prepared, and a corresponding test niobium seed layer is grown on each set of test silicon substrates. Then, at each test temperature, the corresponding test tantalum film at the different test temperatures is grown on the test niobium seed layer grown on each test silicon substrate, resulting in 201 test tantalum films.

[0096] In step 302, X-ray diffraction measurement is performed on each test tantalum film according to the first preset diffraction angle to obtain the test intensity of the X-rays reflected back by each test tantalum film at the first preset diffraction angle, and the test temperature corresponding to the test tantalum film with the largest test intensity is determined as the preset temperature.

[0097] At different test temperatures, the efficiency with which the metastable structure of the β-phase tantalum film crosses the barrier layer and reaches the α-phase tantalum film varies. Therefore, 201 test tantalum films can be tested, and X-ray diffraction measurements can be performed on each test tantalum film at a first preset diffraction angle of 38.23 degrees to obtain the test intensity of the X-rays reflected back by each test tantalum film at the first preset diffraction angle.

[0098] It should be noted that since the test intensity of the X-rays reflected back at the diffraction angle of 38.23 degrees represents the purity of the α-phase tantalum film, the higher the purity of the α-phase tantalum film, the greater the test intensity of the X-rays reflected back at the diffraction angle of 38.23 degrees. Therefore, the test tantalum film with the highest test intensity can be regarded as the α-phase tantalum film with the highest purity, and the test temperature of the test tantalum film with the highest test intensity is the most suitable preset temperature. For example, when 350 degrees Celsius is used as the test temperature, the test intensity of the tantalum film measured is the highest. Therefore, 350 degrees Celsius can be used as the preset temperature. In this way, in actual quantum chip production, the α-phase tantalum film with the highest purity can be grown on the niobium seed layer at the most suitable preset temperature. This can avoid the high two-level loss in the quantum chip obtained by subsequent processing, increase the coherence time of the quantum bit, improve the relaxation time, and thus improve the computing power of the quantum computer.

[0099] In step 303 , a preset metal seed layer with a first preset thickness is grown on the substrate by using a first preset coating power, a first preset argon gas flow rate, and a first preset target-substrate distance.

[0100] Here, the test substrate is a silicon substrate, and the preset metal seed layer is a niobium seed layer. The first preset coating power is a coating power that is manually preset to achieve stable growth of the niobium seed layer, and can be, for example, 190 watts. The first preset argon flow rate is an argon flow rate that is manually preset to achieve stable growth of the niobium seed layer, and can be, for example, 2.5 standard cubic centimeters per minute. The first preset target-substrate distance is a target-substrate distance that is manually preset to achieve stable growth of the niobium seed layer, and can be, for example, 100 mm (millimeter). The first preset thickness is the thickness of the grown stable niobium seed layer, and can be, for example, 2 nm. In this way, in the actual quantum chip processing process, a stable niobium seed layer with a first preset thickness of 2 nm can be grown on a silicon substrate by using a first preset coating power of 190 watts, a first preset argon flow rate of 2.5 standard cubic centimeters per minute, and a first preset target-substrate distance of 100 mm.

[0101] In step 304 , a tantalum film of a target shape with a second preset thickness is grown on the preset metal seed layer by using a second preset coating power, a second preset argon gas flow rate, a second preset target-substrate distance, and a preset temperature.

[0102] The second preset coating power is a manually preset coating power for achieving stable growth of a tantalum film of a target morphology, and can be, for example, 170 watts. The second preset argon flow rate is a manually preset argon flow rate for achieving stable growth of a tantalum film of a target morphology, and can be, for example, 10 standard cubic centimeters per minute. The second preset target-substrate distance is a manually preset target-substrate distance for achieving stable growth of a tantalum film of a target morphology, and can be, for example, 100 mm. The second preset thickness is the thickness of the grown tantalum film of a stable target morphology, and can be, for example, 200 nm. The preset temperature is the temperature for achieving growth of a high-purity tantalum film of a target morphology, and through previous temperature testing, the preset temperature can be determined to be, for example, 350 degrees Celsius. Thus, a stable and highest-purity tantalum film of a target morphology of 200 nm can be grown using a second preset coating power of 170 watts, a second preset argon flow rate of 10 standard cubic centimeters per minute, a second preset target-substrate distance of 100 mm, and a preset temperature of 350 degrees Celsius. In this way, the corresponding quantum chip produced based on the tantalum film of the target form can avoid the generation of high two-level loss to the greatest extent, increase the coherence time of the quantum bit, improve the relaxation time, and thus enhance the computing power of the quantum computer.

[0103] As can be seen from the above, the embodiments of the present application grow a preset metal seed layer on a substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; and grow a tantalum film of a target morphology on the preset metal seed layer at a preset temperature, wherein the preset temperature is not less than 300 degrees Celsius. Thus, by adding a layer of the preset metal seed layer to the substrate, a tantalum film with a lattice constant close to that of the preset metal seed layer can be subsequently grown, rather than a tantalum film with a lattice constant close to that of the substrate. Furthermore, a tantalum film of the target morphology is obtained by applying a high temperature to the preset metal seed layer. Compared to the related art method of directly growing a tantalum film on a sapphire substrate and using the tantalum film to prepare a quantum chip, the tantalum film of the target morphology obtained in the embodiments of the present application can reduce the interaction with microwaves in the quantum chip when used to prepare a quantum chip, thereby reducing two-level loss, increasing the coherence time of the quantum bit, and thereby improving the relaxation time, thereby increasing the computing power of the quantum computer.

[0104] The embodiment of the present application can also use XRD measurement to find the preset temperature at which the metastable structure of the β-phase tantalum film crosses the barrier layer to reach the α-phase tantalum film with the highest efficiency from different test temperatures, and use this preset temperature to achieve subsequent high-temperature treatment of the tantalum film. In this way, the two-level loss can be further reduced, the coherence time of the quantum bit can be increased, and the relaxation time can be improved, thereby increasing the computing power of the quantum computer.

[0105] The specific implementation of the above steps can be found in the previous embodiments and will not be repeated here.

[0106] To facilitate better implementation of the tantalum film growth method provided in the embodiments of this application, the embodiments of this application also provide an apparatus based on the aforementioned tantalum film growth method. The meanings of the terms herein are the same as those in the aforementioned tantalum film growth method. For specific implementation details, please refer to the description in the method embodiments.

[0107] Please refer to Figure 9, which is a schematic diagram of the structure of a tantalum film growth apparatus provided in an embodiment of the present application. The tantalum film growth apparatus is applied to a computer device, which can control a corresponding vacuum electron beam coating machine to perform film coating operations. The tantalum film growth apparatus may include a first growth unit 401 and a second growth unit 402.

[0108] The first growth unit 401 is configured to grow a preset metal seed layer on a substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; the second growth unit 402 is configured to grow a tantalum film of a target morphology on the preset metal seed layer at a preset temperature, and the preset temperature is greater than or equal to 300 degrees Celsius.

[0109] In some embodiments, the second growth unit 402 is further configured to grow a tantalum film on the preset metal seed layer at the preset temperature; perform X-ray diffraction measurement on the tantalum film to obtain an X-ray diffraction measurement result; and determine, based on the X-ray diffraction measurement result, that the tantalum film grown on the preset metal seed layer is a tantalum film of the target morphology.

[0110] In some embodiments, the X-ray diffraction measurement results include: the intensity of the X-rays reflected back by the tantalum film at different diffraction angles; the second growth unit 402 is further configured to determine that the morphology of the tantalum film is the target morphology when it is detected that the intensity of the X-rays reflected back at a first preset diffraction angle is the largest among the intensities of the X-rays reflected back at the different diffraction angles.

[0111] In some embodiments, the first preset diffraction angle is a diffraction angle of 38.23 degrees formed with the substrate.

[0112] In some embodiments, the target morphology is an alpha phase.

[0113] In some embodiments, the preset metal in the preset metal seed layer is niobium; the first growth unit 401 is further configured to grow a preset metal seed layer of a first preset thickness on the substrate through a first preset coating power, a first preset argon gas flow rate and a first preset target-substrate distance.

[0114] In some embodiments, the first preset coating power is 190 watts, the first preset argon gas flow rate is 2.5 standard cubic centimeters per minute, the first preset target-substrate distance is 100 mm, and the first preset thickness is 2 nanometers.

[0115] In some embodiments, the second growth unit 402 is further configured to grow a tantalum film of a target morphology with a second preset thickness on the preset metal seed layer through a second preset coating power, a second preset argon gas flow rate, a second preset target-substrate distance and the preset temperature.

[0116] In some embodiments, the second preset coating power is 170 watts, the second preset argon gas flow rate is 10 standard cubic centimeters per minute, the second preset target-substrate distance is 100 mm, and the second preset thickness is 200 nanometers.

[0117] In some embodiments, the preset temperature is between 300 degrees Celsius and 500 degrees Celsius.

[0118] In some embodiments, the device also includes a testing unit configured to: grow a test preset metal seed layer on a test substrate; select different test temperatures in sequence from a target temperature range; and grow different test tantalum films on the test preset metal seed layer at different test temperatures; perform X-ray diffraction measurement on each test tantalum film according to a first preset diffraction angle to obtain a test intensity of X-rays reflected back by each test tantalum film at the first preset diffraction angle; and determine the test temperature corresponding to the test tantalum film with the largest test intensity as the preset temperature.

[0119] In some embodiments, the target temperature range is from 300 degrees Celsius to 500 degrees Celsius.

[0120] In some embodiments, the substrate is a silicon substrate.

[0121] The specific implementation of each of the above units can be found in the previous embodiments and will not be described again here.

[0122] As can be seen from the above, in the embodiment of the present application, a predetermined metal seed layer is grown on a substrate by a first growth unit 401; wherein the absolute value of the difference between the lattice constant of the predetermined metal seed layer and the lattice constant of the substrate is greater than a predetermined threshold; and a second growth unit 402 grows a tantalum film of a target morphology on the predetermined metal seed layer at a predetermined temperature, wherein the predetermined temperature is greater than or equal to 300 degrees Celsius. Thus, by adding a predetermined metal seed layer to the substrate, a tantalum film having a lattice constant close to that of the predetermined metal seed layer can be subsequently grown, rather than a tantalum film having a lattice constant close to that of the substrate. Furthermore, a tantalum film of a target morphology is obtained by applying a high temperature to the predetermined metal seed layer. Compared to the related art method of directly growing a tantalum film on a sapphire substrate for preparing a quantum chip, the tantalum film of the target morphology obtained in the embodiment of the present application can reduce interaction with microwaves in the quantum chip, thereby reducing two-level loss, increasing the coherence time of the quantum bit, and thereby improving the relaxation time, thereby increasing the computing power of the quantum computer.

[0123] The specific implementation of each of the above units can be found in the previous embodiments and will not be described again here.

[0124] An embodiment of the present application further provides a quantum chip, which includes at least a transition layer and an electrode, and the transition layer and the electrode are made of a tantalum film, and the tantalum film is generated using the tantalum film growth method in the above embodiment.

[0125] An embodiment of the present application further provides a quantum computer, which includes at least the above-mentioned quantum chip.

[0126] Referring to FIG10 , FIG10 is a block diagram of a portion of a terminal 140 implementing an embodiment of the present application. The terminal 140 is a computer device for implementing a tantalum film growth method. The terminal 140 includes components such as a radio frequency (RF) circuit 510, a memory 515, an input unit 530, a display unit 540, a sensor 550, an audio circuit 560, a wireless fidelity (WiFi) module 570, a processor 580, and a power supply 590. Those skilled in the art will appreciate that the structure of the terminal 140 shown in FIG10 does not limit the structure of a mobile phone or a computer, and may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0127] The RF circuit 510 can be used to receive and transmit signals during information transmission or calls. Specifically, it receives downlink information from the base station and transmits it to the processor 580 for processing. Furthermore, it transmits uplink data to the base station. The memory 515 can be used to store software programs and modules. The processor 580 executes the software programs and modules stored in the memory 515 to execute various terminal functions and data processing. The input unit 530 can be used to receive input digital or character information and generate key input signals related to terminal settings and function control. The input unit 530 may include a touch panel 531 and other input devices 532. The display unit 540 can be used to display input or provided information, as well as various menus of the terminal. The display unit 540 may include a display panel 541. The audio circuit 560, speaker 561, and microphone 562 provide an audio interface.

[0128] In this embodiment, the processor 580 included in the terminal 140 can execute the tantalum film growth method provided in the previous embodiment, for example, the following steps can be performed: first, controlling the vacuum electron beam coating machine to grow a preset metal seed layer on the substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; then, controlling the growth of a target tantalum film on the preset metal seed layer at a preset temperature, and the preset temperature is not less than 300 degrees Celsius.

[0129] The terminal 140 of the embodiment of the present application includes but is not limited to mobile phones, computers, intelligent voice interaction devices, smart home appliances, vehicle terminals, aircraft, etc. The embodiment of the present application can be applied to various scenarios, including but not limited to cloud technology, artificial intelligence, smart transportation, assisted driving, etc.

[0130] FIG11 is a block diagram of a portion of a server 110 for implementing an embodiment of the present application. The server 110 is another implementation device of a computer device for implementing a tantalum film growth method. The server 110 may have relatively large differences due to different configurations or performances, and may include one or more central processing units (CPUs) 622 (for example, one or more processors) and a memory 632, and one or more storage media 630 (for example, one or more mass storage devices) for storing application programs 642 or data 644. The memory 632 and the storage medium 630 may be temporary storage or permanent storage. The program stored in the storage medium 630 may include one or more modules (not shown in the figure), each module of which may include a series of instruction operations on the server 600. The central processing unit 622 may be configured to communicate with the storage medium 630 and execute a series of instruction operations in the storage medium 630 on the server 600.

[0131] The server 600 may also include one or more power supplies 626, one or more wired or wireless network interfaces 650, one or more input and output interfaces 658, and one or more operating systems 641, such as Windows Server™, Mac OS X™, Unix™, Linux™, FreeBSD™, etc.

[0132] The central processing unit 622 in the server 600 can be used to execute the tantalum film growth method of the embodiment of the present application. For example, the following steps can be performed: first, the vacuum electron beam coating machine is controlled to grow a preset metal seed layer on the substrate; wherein the absolute value of the difference between the lattice constant of the preset metal seed layer and the lattice constant of the substrate is greater than a preset threshold; then, a tantalum film of a target morphology is grown on the preset metal seed layer under control at a preset temperature, and the preset temperature is not less than 300 degrees Celsius.

[0133] An embodiment of the present application further provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the tantalum film growth method of each of the aforementioned embodiments.

[0134] The present application also provides a computer program product, which includes a computer program. A processor of a computer device reads and executes the computer program, causing the computer device to implement the aforementioned tantalum film growth method. For example, first, a vacuum electron beam coating machine is controlled to grow a predetermined metal seed layer on a substrate; wherein the absolute value of the difference between the lattice constant of the predetermined metal seed layer and the lattice constant of the substrate is greater than a predetermined threshold; then, a tantalum film of a target morphology is grown on the predetermined metal seed layer at a predetermined temperature, wherein the predetermined temperature is not less than 300 degrees Celsius.

[0135] In addition, the terms "comprises" and "comprising" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or apparatus that comprises a series of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, product or apparatus.

[0136] It should be understood that, in this application, "at least one (item)" means one or more, and "plurality" means two or more. "At least one of the following (items)" or similar expressions refers to any combination of these items, including any combination of single items (items) or plural items (items). For example, at least one of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or plural.

[0137] It should be understood that in the description of the embodiments of the present application, multiple (or multiple items) means more than two, greater than, less than, exceed, etc. are understood to exclude the number itself, and above, below, within, etc. are understood to include the number itself.

[0138] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0139] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0140] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0141] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a program product, and the computer program product is stored in a computer-readable storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0142] It should also be understood that the various implementation methods provided in the embodiments of the present application can be combined arbitrarily to achieve different technical effects.

[0143] In the embodiments of the present application, the term "module" or "unit" refers to a computer program or a part of a computer program that has a predetermined function and works together with other related parts to achieve a predetermined goal, and can be implemented in whole or in part by using software, hardware (such as processing circuits or memories) or a combination thereof. Similarly, a processor (or multiple processors or memories) can be used to implement one or more modules or units. In addition, each module or unit can be part of an overall module or unit that includes the function of the module or unit.

[0144] The above is a specific description of the implementation methods of the present application, but the present application is not limited to the above implementation methods. Technical personnel familiar with the art can also make various equivalent modifications or substitutions without violating the spirit of the present application. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A tantalum film growth method, the method being executed by a computer device, comprising: Growing a preset metal seed layer on a substrate; wherein an absolute value of a difference between a lattice constant of the preset metal seed layer and a lattice constant of the substrate is greater than a preset threshold; A tantalum film of a target shape is grown on the preset metal seed layer at a preset temperature, wherein the preset temperature is greater than or equal to 300 degrees Celsius.

2. The tantalum film growth method according to claim 1, wherein: The method of growing a tantalum film of a target shape on the preset metal seed layer at a preset temperature comprises: At the preset temperature, growing a tantalum film on the preset metal seed layer; Performing X-ray diffraction measurement on the tantalum film to obtain an X-ray diffraction measurement result; According to the X-ray diffraction measurement result, it is determined that the tantalum film grown on the preset metal seed layer is a tantalum film of a target morphology.

3. The tantalum film growth method according to claim 1 or 2, wherein: The X-ray diffraction measurement results include: the intensity of X-rays reflected back by the tantalum film at different diffraction angles; The step of determining, based on the X-ray diffraction measurement result, that the tantalum film grown on the preset metal seed layer is a tantalum film of a target morphology comprises: When it is detected that the intensity of the X-rays reflected back at the first preset diffraction angle is the largest among the intensities of the X-rays reflected back at the different diffraction angles, it is determined that the morphology of the tantalum film is the target morphology.

4. The tantalum film growth method according to any one of claims 1 to 3, wherein: The first preset diffraction angle is a diffraction angle of 38.23 degrees formed with the substrate.

5. The tantalum film growth method according to any one of claims 1 to 4, wherein: The target morphology is the alpha phase.

6. The tantalum film growth method according to any one of claims 1 to 5, wherein: The preset metal in the preset metal seed layer is niobium, and the step of growing the preset metal seed layer on the substrate includes: A preset metal seed layer with a first preset thickness is grown on the substrate by means of a first preset coating power, a first preset argon gas flow rate and a first preset target-substrate distance.

7. The tantalum film growth method according to any one of claims 1 to 6, wherein: The first preset coating power is 190 watts, the first preset argon gas flow rate is 2.5 standard cubic centimeters per minute, the first preset target-substrate distance is 100 millimeters, and the first preset thickness is 2 nanometers.

8. The tantalum film growth method according to any one of claims 1 to 7, wherein: The method of growing a tantalum film of a target shape on the preset metal seed layer at a preset temperature comprises: A tantalum film of a target shape with a second preset thickness is grown on the preset metal seed layer by means of a second preset coating power, a second preset argon gas flow rate, a second preset target-substrate distance and the preset temperature.

9. The tantalum film growth method according to any one of claims 1 to 8, wherein: The second preset coating power is 170 watts, the second preset argon gas flow rate is 10 standard cubic centimeters per minute, the second preset target-substrate distance is 100 millimeters, and the second preset thickness is 200 nanometers.

10. The tantalum film growth method according to any one of claims 1 to 9, wherein: The preset temperature is between 300 degrees Celsius and 500 degrees Celsius.

11. The tantalum film growth method according to any one of claims 1 to 10, wherein: The method further comprises: Growing a test preset metal seed layer on a test substrate; Selecting different test temperatures from the target temperature range in turn; and growing different test tantalum films on the test preset metal seed layer at different test temperatures; According to the first preset diffraction angle, an X-ray diffraction measurement is performed on each test tantalum film to obtain each test tantalum film A test intensity of X-rays reflected back at a first preset diffraction angle; The test temperature corresponding to the test tantalum film with the largest test intensity is determined as the preset temperature.

12. The tantalum film growth method according to any one of claims 1 to 11, wherein: The target temperature range is from 300 degrees Celsius to 500 degrees Celsius.

13. The tantalum film growth method according to any one of claims 1 to 12, wherein: The substrate is a silicon substrate.

14. A quantum chip, comprising at least a transition layer and an electrode, wherein the transition layer and the electrode are made of a tantalum film, and the tantalum film is generated by the tantalum film growth method according to any one of claims 1 to 13.

15. A quantum computer, comprising the quantum chip according to claim 14.

16. A tantalum film growth device, comprising: A first growth unit is configured to grow a preset metal seed layer on a substrate; wherein an absolute value of a difference between a lattice constant of the preset metal seed layer and a lattice constant of the substrate is greater than a preset threshold; The second growth unit is configured to grow a tantalum film of a target shape on the preset metal seed layer at a preset temperature, and the preset temperature is greater than or equal to 300 degrees Celsius.

17. A computer-readable storage medium storing a plurality of computer programs, wherein the computer programs are suitable for being loaded by a processor to execute the tantalum film growth method according to any one of claims 1 to 13.

18. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the tantalum film growth method according to any one of claims 1 to 13 when executing the computer program.

19. A computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the tantalum film growth method according to any one of claims 1 to 13 is implemented.

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