Atomic layer deposition control method and control apparatus, deposition apparatus

Abstract

The application relates to an atomic layer deposition control method and a control device and a deposition device, and the method comprises the following steps: controlling a process chamber to perform N target process steps to deposit a target film layer with a target thickness on a wafer surface in the process chamber; wherein the i-th target process step comprises the following steps: during the process chamber is filled with alternating precursor gas, the excitation source is controlled to apply a first magnetic field to the process chamber, and the wafer carrier is controlled to apply an electrostatic field to the wafer surface, so that the film-forming target ions decomposed from the precursor gas accelerate towards the wafer surface, are adsorbed on the wafer surface or react with the target ions that have been adsorbed to form the i-th layer of atomic thin film, i [1, N]. According to the electric state and the charge amount of the precursor gas decomposition ions, the direction and the strength of the applied magnetic field and the electric field are flexibly adjusted, so that the process temperature window is expanded, the thin film deposition period is shortened, and the uniformity of the thin film is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated circuits, and in particular to an atomic layer control method, a control device and a deposition device. BACKGROUND

[0002] With the continuous development of the semiconductor industry, the size of devices is becoming more and more fine, so it is particularly important to find or develop more advanced thin film growth technology, which requires low thermal budget, high thin film thickness precision and excellent conformality on three-dimensional (3D) structures. Atomic layer deposition (ALD) technology is distinguished from traditional deposition technology due to its high controllability of deposition parameters (thickness, composition and structure), excellent uniformity and conformality, so it has wide application potential in the field of micro-nano electronics. However, the ALD process rate is relatively low, which limits its application in some fields.

[0003] Shortening the deposition cycle is one of the main ways to improve the growth rate. The specific methods include shortening the ventilation time of the precursor gas flowing into the reaction chamber, and shortening the purging time of the reaction chamber before emptying the precursor gas. However, too short ventilation time will result in insufficient contact of the precursor gas with the wafer surface, affecting the film quality; too short purging time will result in desorption of the adsorbed molecules on the wafer surface, also affecting the film quality. In addition, the ALD process has a clear temperature window, and too low or too high process temperature will affect the reaction rate and the quality of the deposited thin film.

[0004] Therefore, it is necessary to optimize the ventilation time, purging time and process temperature to ensure the quality of the thin film while improving the growth rate. SUMMARY

[0005] Therefore, it is necessary to optimize the ventilation time, purging time and process temperature to ensure the quality of the thin film while improving the growth rate.

[0006] In a first aspect, the present application provides an atomic layer deposition control method, comprising:

[0007] controlling a process chamber to perform N target process steps to deposit a target film layer of a target thickness on a wafer surface in the process chamber; wherein performing the ith target process step comprises:

[0008] during the period of introducing the first precursor gas into the process chamber, controlling the excitation source to apply a first magnetic field to the process chamber, and controlling the wafer carrier to apply a first electrostatic field to the wafer surface, so that the first film-forming target ions decomposed from the first precursor gas accelerate towards the wafer surface and are adsorbed on the wafer surface;

[0009] During the introduction of the second precursor gas into the process chamber, the magnetization source is controlled to apply a second magnetic field into the process chamber, and the wafer carrier is controlled to apply a second electrostatic field to the wafer surface, so that the second film-forming target ions decomposed from the second precursor gas accelerate toward the wafer surface, react with the first film-forming target ions, and form the i-th layer of atomic thin film, i ∈ [1, N].

[0010] In the atomic layer deposition control method in the above embodiment, a variable longitudinal magnetic field perpendicular to the wafer surface is applied in the process chamber, effectively guiding and driving the film-forming target ions decomposed from the precursor gas to move quickly toward the wafer surface, accelerating the process of the film-forming target ions approaching and adsorbing on the wafer surface. At the same time, an electrostatic field is formed on the wafer surface by an external voltage, which accelerates the adsorption of the film-forming target ions on the wafer surface by electrostatic field-induced adsorption, and enhances the adsorption strength, reduces the probability of desorption in high temperature environment, and achieves the purpose of anchoring the adsorbed film-forming target ions and widening the process temperature window.

[0011] In addition to the above advantages, the electromagnetic field assisted atomic layer deposition control method has the advantages of environmental protection and energy saving, including reducing material consumption, reducing energy consumption, and not introducing impurities, avoiding the use of chemical reagents, and further reducing environmental pollution.

[0012] Under the joint action of the above technical features, the ALD process deposition rate is improved, the thin film deposition uniformity and density are enhanced, and the ALD process rate and thin film quality are synergistically improved. By further optimizing the process parameters, the ALD process rate and thin film quality can be further improved to meet the harsh requirements of different application fields. The synergistic electromagnetic field technology provides a green and efficient new way for the optimization of ALD process and the preparation of advanced thin film materials.

[0013] In some embodiments, the performing the i-th target process step further includes:

[0014] Before the second precursor gas is introduced into the process chamber, and during the introduction of the purge gas into the process chamber, the wafer carrier is controlled to continuously apply the first electrostatic field to the wafer surface.

[0015] In some embodiments, the performing the i-th target process step further includes: after forming the first layer of atomic thin film, and during the introduction of the purge gas into the process chamber, the wafer carrier is controlled to continuously apply the second electrostatic field to the wafer surface, wherein the second electrostatic field is associated with the adsorption force of the first film-forming target ions on the wafer surface.

[0016] In some embodiments, the first film-forming target ions and the second film-forming target ions have opposite electrical properties.

[0017] In some embodiments, the second precursor gas decomposes second film-forming target ions and second film-forming byproduct ions; the second film-forming target ions and the second film-forming byproduct ions have opposite electrical properties.

[0018] In a second aspect, the present application also provides an atomic layer deposition control device, which is configured to control a process chamber to perform N target process steps to deposit a target film layer with a target thickness on a wafer surface in the process chamber; the control device comprises a magnetic excitation source, a wafer carrier, and a controller connected to the magnetic excitation source and the wafer carrier, and configured to perform the following steps during the i-th target process step:

[0019] During the introduction of the first precursor gas into the process chamber, the controller controls the magnetic excitation source to apply a first magnetic field to the process chamber and controls the wafer carrier to apply a first electrostatic field to the wafer surface, so that first film-forming target ions decomposed from the first precursor gas accelerate toward the wafer surface and are adsorbed on the wafer surface.

[0020] During the introduction of the second precursor gas into the process chamber, the controller controls the magnetic excitation source to apply a second magnetic field to the process chamber and controls the wafer carrier to apply a second electrostatic field to the wafer surface, so that second film-forming target ions decomposed from the second precursor gas accelerate toward the wafer surface, react with the first film-forming target ions, and form an i-th layer of atomic thin film, i∈[1,N].

[0021] In the atomic layer deposition control device in the above embodiments, the variable longitudinal magnetic field perpendicular to the wafer surface is applied in the process chamber to drive the film-forming target ions decomposed from the heated precursor gas to move rapidly toward the wafer surface, thereby shortening the time for the film-forming target ions to approach and be adsorbed on the wafer surface. Meanwhile, the device forms an electrostatic field on the wafer surface by applying a voltage, and accelerates the adsorption of the film-forming target ions on the wafer surface and enhances the adsorption strength by means of electrostatic field-induced adsorption, thereby reducing the probability of desorption in subsequent purging and high-temperature environments. The electrostatic field can anchor the adsorbed film-forming target ions, widen the process temperature window, and further shorten the deposition period.

[0022] The synergistic effect of the electromagnetic field brings multiple advantages, including shortening the purging and purging time, widening the temperature window, reducing desorption, improving the quality of the thin film, and being green and environmentally friendly. The production cost is reduced due to the faster deposition rate and more excellent thin film performance without introducing other impurities. The uniform and dense thin film has better electrical, optical, and mechanical properties, which widens the application field of ALD technology and enables it to be applied in the fields of flexible electronics, biomedicine, and nanotechnology.

[0023] In some embodiments, the controller also performs the following steps during the i-th target process step:

[0024] Before the second precursor gas is introduced into the process chamber, and during the purge gas is introduced into the process chamber, the wafer carrier is controlled to continuously apply the first electrostatic field to the wafer surface.

[0025] In some embodiments, the controller further performs the following steps during performing the i-th target process step:

[0026] After forming the first layer of the atomic thin film, and during the purge gas is introduced into the process chamber, the wafer carrier is controlled to continuously apply the second electrostatic field to the wafer surface, wherein the second electrostatic field is associated with the adsorption force of the first film-forming target ions on the wafer surface.

[0027] In a third aspect, the present application also provides a deposition device, comprising a process chamber and the above-mentioned atomic layer deposition control device.

[0028] In the above-mentioned embodiment device, thanks to the improved ALD process, the deposition device can flexibly adjust the direction and strength of the applied magnetic field and electric field according to the electric state and charge amount of the precursor gas decomposition ions, while maintaining the original thin film quality, thereby expanding the process temperature window, shortening the thin film deposition period, and improving the thin film uniformity. In addition, the electromagnetic field assisted technology also avoids the use of chemical reagents, further reducing environmental pollution. More advanced ALD devices can provide better quality products, enhancing their market competitiveness. In addition, faster ALD deposition rate and better thin film quality will promote the development and innovation of ALD technology, laying the foundation for the development of new materials and new devices. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0030] Figure 1 A flow chart of the atomic layer deposition control method provided in an embodiment;

[0031] Figure 2 A cross-sectional schematic view of the structure obtained after the wafer is provided in step S202 in the atomic layer deposition control method provided in an embodiment;

[0032] Figure 3 A cross-sectional schematic view of the structure obtained after the first precursor gas is introduced in step S204 in the atomic layer deposition control method provided in an embodiment;

[0033] Figure 4A cross-sectional view of the structure obtained after the purge gas is introduced in step S210 of the atomic layer deposition control method provided in an embodiment;

[0034] Figure 5 A cross-sectional view of the structure obtained after the second precursor gas is introduced in step S402 of the atomic layer deposition control method provided in an embodiment;

[0035] Figure 6 A cross-sectional view of the structure obtained after the purge gas is introduced again in step S406 of the atomic layer deposition control method provided in an embodiment;

[0036] Figure 7 A cross-sectional view of the structure obtained after the first atomic thin film is formed in step S406 of the atomic layer deposition control method provided in an embodiment;

[0037] Figure 8 A circuit diagram of an atomic layer deposition control device provided in an embodiment.

[0038] Explanation of reference numerals:

[0039] 10, wafer; 20, atom of the first precursor gas; 21, first film formation byproduct ion; 22, first film formation target ion; 30, atom of the second precursor gas; 31, second film formation byproduct ion; 32, second film formation target ion; 40, first atomic thin film. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The preferred embodiments of the present application are given in the accompanying drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present application will be more thorough and complete.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0042] It will be understood that when an element or layer is referred to as being "on" or "connected to" another element or layer, it can be directly on or connected to the other element or layer or intervening elements or layers can be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element or layer, there are no intervening elements or layers present. It will also be understood that, although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section; for example, a first doped type could be termed a second doped type; and similarly, a second doped type could be termed a first doped type; a first doped type and a second doped type are different doped types, e.g., a first doped type can be p-type and a second doped type can be n-type, or the first doped type can be n-type and the second doped type can be p-type.

[0043] Spatially relative terms, such as "beneath", "below", "lower", "under", "above", "upper" and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and / or operation in addition to the orientations depicted in the figures. For example, if a device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can also be oriented in the other direction (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0044] The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. In addition, use of the term "and / or" includes any and all combinations of associated items.

[0045] Embodiments of the application are described herein with reference to cross-sectional illustrations that are schematic illustrations of ideal embodiments (and intermediate structures) of the application. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Thus, embodiments of the application should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an implanted region illustrated as a rectangle will, typically, have rounded or curved features and / or a gradient of implant concentration at its edges rather than a binary change between implanted and non-implanted regions. Similarly, a buried region formed by implantation can result in some implantation in a region between the buried region and a surface through which the implant was performed. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the application.

[0046] Referring now to the drawings, wherein like reference numerals designate similar structures throughout the several views, Figure 1 The present application provides an atomic layer deposition control method, comprising: steps S20-S60.

[0047] Step S20: during the process of introducing the first precursor gas into the process chamber, the first magnetic field is applied to the process chamber by the excitation source, and the first electrostatic field is applied to the wafer surface by the wafer carrier, so that the first film-forming target ions decomposed from the first precursor gas accelerate towards the wafer surface and are adsorbed on the wafer surface.

[0048] Unlike traditional chemical vapor deposition (CVD), ALD is a chemical vapor thin film deposition technology based on ordered and surface self-saturation reactions, which deposits thin film materials on the wafer surface in the form of single-atom films layer by layer based on chemical vapor deposition. The reaction precursor gas is deposited alternately, and the chemical reaction of a new layer of atoms is directly associated with the previous layer, and only one layer of atoms is deposited each time. It has the characteristics of self-limiting growth, which can make the thin film conformal and pinhole-free deposition on the substrate. Therefore, the thickness of the thin film can be accurately controlled by controlling the number of deposition cycles.

[0049] By way of example, the wafer can be made of a semiconductor material, an insulating material, a conductive material, or any combination thereof. It can also be a single-layer structure or a multi-layer structure. For example, the substrate can be, for example, silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), sapphire (Al2O3), silicon oxide (SiO2), silicon nitride (Si3N4), aluminum oxide (Al2O3), or, for example, include materials such as metals, polymers, and glasses. Therefore, the type of substrate should not limit the scope of protection of the present disclosure.

[0050] As an example, the precursor gas needs to have the following characteristics: easy to gasify, capable of chemisorption or strong chemical reaction with the wafer surface, and no gas phase reaction product; the byproduct is usually gaseous, which is convenient to remove by purging gas; and it will not cause corrosion to the film or wafer surface. Common precursor gases include, but are not limited to, the following two categories: inorganic and metal organic. Among them, inorganic precursors include elements and halides, and metal organic precursors include metal alkyls, metal cyclopentadienyls, metal β-2 ketones, metal amides, and metal ether groups. The selection of the precursor gas depends on the desired deposited film material and properties, ensuring stable ALD process and excellent film quality.

[0051] As an example, in this embodiment, the wafer surface is negatively charged under the action of the first electrostatic field; and the first film-forming target ion decomposed from the first precursor gas is positively charged. Therefore, the positively charged ions are accelerated to move towards the substrate surface under the action of the external magnetic field force and the electric field attraction force.

[0052] Step S40: During the introduction of the second precursor gas into the process chamber, the excitation source is controlled to apply a second magnetic field to the process chamber, and the wafer carrier is controlled to apply a second electrostatic field to the wafer surface, so that the second film-forming target ion decomposed from the second precursor gas is accelerated to move towards the wafer surface, reacts with the first film-forming target ion, and forms an i-layer atomic film, i∈[1,N].

[0053] As an example, the second precursor gas is complementary to the first precursor gas.

[0054] In this embodiment, the wafer surface is positively charged under the action of the second electrostatic field; and the second film-forming target ion decomposed from the second precursor gas is negatively charged.

[0055] As an example, the repulsion and attraction effect plays an important role in the electric field, which makes the positive and negative charges uniformly distributed on the substrate, improving the uniformity of the film. The strength of the magnetic field and the electrostatic field can be adjusted as needed, which is not specifically limited herein.

[0056] In addition, the electromagnetic field assisted deposition has the advantages of environmental protection and energy saving, including reducing material consumption, reducing energy consumption, not introducing impurities, avoiding the use of chemical reagents, and further reducing environmental pollution.

[0057] The semiconductor structure obtained after steps S20-S40 can be referred to in Figure 7 Of course, in order to facilitate the understanding of the present application, Figure 7 An example of a film layer prepared by using the atomic deposition control method of the present application is given, and other suitable examples of the film layer prepared by using the present application are also possible, which are not limited herein.

[0058] Step S60: Perform N times of target process steps to deposit a target film layer with a target thickness on the wafer surface.

[0059] As an example, the concept of N times of target process cycles is relevant to the discussion of the embodiments herein. Performing one target process step results in the creation of at least a portion of a target film layer on the wafer surface, and the number of times depends on the final thickness of the target film layer required. Each of the process steps has the same precursor gas, purge gas, and processing conditions. In the disclosed embodiments, N can be any integer greater than or equal to 2. Typically, certain auxiliary operations can also be included in performing N times of target process steps, such as cleaning the wafer surface before introducing the precursor gas and / or processing a portion of the deposited film.

[0060] The target film layer includes, but is not limited to, high-k dielectric film layers such as aluminum oxide (AI2O3), hafnium sulfide (HfO2), tantalum pentoxide (Ta2O5), etc. for transistor gate and dynamic random access memory (DRAM); metal gate electrode films such as iridium (Ir), platinum (Pt), ruthenium (Ru), etc.; metal interconnects and liners such as copper (Cu), tungsten nitride (WN), tungsten carbon nitride (WNC), etc.; metal diffusion barrier layers for copper interconnects; semiconductor vias for transistor gates; and storage cell applications such as DRAM capacitors; and passivation layers.

[0061] In the above embodiments, a variable longitudinal magnetic field is applied inside the process chamber perpendicular to the wafer surface, which drives the deposition of target ions to move rapidly towards the wafer surface to shorten the purge time. At the same time, an electrostatic field is formed by applying a voltage on the wafer surface, which accelerates the adsorption of reaction precursor atoms on the wafer surface through electric field-induced adsorption, shortens the purge time, and the electrostatic field can anchor the adsorbed atoms to enhance their adsorption strength, avoiding desorption of the precursor atoms during the purge and in a high-temperature environment.

[0062] Referring to Figures 3-4 In some embodiments, step S20 further comprises:

[0063] Step S202: Provide the wafer 10 to be placed in the process chamber and set the deposition temperature.

[0064] For example, before starting the process, the process chamber is preheated to the required process temperature, ensuring that the temperature inside the process chamber reaches a stable temperature, and the wafer 10 is placed in the wafer carrier so that the temperature of the wafer 10 is synchronized with the temperature of the process chamber.

[0065] Step S204: the first precursor gas atom 20 is introduced into the process chamber, and the first film-forming target ion 22 and the first film-forming byproduct ion 21 are generated by thermal decomposition of the first precursor gas atom 20; the first film-forming target ion 22 and the first film-forming byproduct ion 21 have opposite electric properties.

[0066] For example, please continue to refer to Figure 3 In the present embodiment, the first film-forming target ion 22 is a positive ion, and the first film-forming byproduct ion 21 is a negative ion.

[0067] Step S206: the first magnetic field is applied by controlling the excitation source, and the first electrostatic field is applied to the surface of the wafer 10, so that the first film-forming target ion 22 generated by the decomposition of the first precursor gas atom 20 accelerates towards the surface of the wafer 10 and is adsorbed on the surface of the wafer 10;

[0068] For example, please continue to refer to Figure 3 Since the first electrostatic field makes the wafer surface 10 have a negative charge, the first film-forming target ion 22 with positive electric property accelerates towards the surface of the wafer 10 under the action of the external magnetic field force and the electric field attraction force, and is adsorbed on the surface of the wafer 10, and the first film-forming byproduct ion 21 with opposite electric property is repelled by the electric field away from the surface of the wafer 10. The byproduct is prevented from entering the film layer to reduce the quality of the thin film; the synergistic effect of the magnetic field and the electric field makes the first film-forming target ion 22 accelerate towards the surface of the wafer 10, and the two fully contact within a preset gas introduction time, achieving the purpose of shortening the deposition time.

[0069] Step S210: before introducing the second precursor gas atom 30 into the process chamber, and during the introduction of the purge gas into the process chamber, the first electrostatic field is continuously applied to the surface of the wafer 10 by controlling the wafer carrier.

[0070] For example, please refer to Figure 4 The electric field can affect the adsorption position and diffusion behavior of the adsorbate on the adsorption surface. When an electric field is applied in an adsorption system, the adsorbate will be affected by the electric field force, thereby changing its adsorption state on the surface. Under the action of the external electric field, the wafer 10 surface also forms an electrostatic field. When there is an electric field on the surface of an object, if there is a charge distribution on the surface, the electric field will exert a force on the charge on the surface. Therefore, the retained external electric field during purging effectively enhances the adsorption force of the first film-forming target ion 22 on the surface of the wafer 10.

[0071] To further shorten the deposition period, the pumping force of the pump is increased to shorten the purge time required for the purge gas. Due to the action of the electrostatic field, the first film-forming target ions 22 are firmly anchored on the surface of the wafer 10, significantly reducing the possibility of desorption phenomenon occurring due to the weakening of the adsorption ability of the film-forming target ions at a higher temperature, and avoiding the occurrence of the uniformity of the subsequent thin film being reduced. In short, this method accelerates the deposition rate by increasing the deposition temperature, while ensuring the stability and quality of the thin film deposition, providing better performance for semiconductor devices prepared based on this technology. The application of this technology is crucial for modern manufacturing processes that pursue high precision and high efficiency.

[0072] Referring to Figures 5-6 In some embodiments, step S40 further comprises:

[0073] Step S402: While the second precursor gas atom 30 decomposes the second film-forming target ion 32, it also decomposes the second film-forming byproduct ion 31; the electrical properties of the second film-forming target ion 32 and the second film-forming byproduct ion 31 are opposite. The electrical properties of the first film-forming target ion 22 and the second film-forming target ion 32 are opposite.

[0074] For example, referring to Figure 5 In this embodiment, the first film-forming target ion 22 is a positive ion, and the second film-forming target ion 32 is a negative ion. The second film-forming byproduct ion 31 has the same electrical properties as the first film-forming target ion 22.

[0075] Step S404: During the introduction of the second precursor gas atom 30 into the process chamber, the excitation source is controlled to apply a second magnetic field to the process chamber, and the wafer carrier is controlled to apply a second electrostatic field to the surface of the wafer 10. The second film-forming target ion 32 decomposed by the second precursor gas atom 30 accelerates towards the surface of the wafer 10, reacts with the first film-forming target ion 22, and forms the i-th layer of atomic thin film,

[0076] For example, referring to Figure 5 At this time, a second magnetic field is applied inside the cavity, which is opposite in direction to the first magnetic field, and also accelerates the movement of the second film-forming target ion 32 with negative electricity towards the surface of the wafer 10. At the same time, a second electrostatic field is applied to the surface of the wafer 10, making the surface of the wafer 10 positively charged. By means of the surface electrostatic field induced adsorption, the second film-forming target ion 32 with negative electricity is accelerated to move towards the surface of the wafer 10 under the action of the electric field attraction, and reacts with the first film-forming target ion 22 which has been adsorbed on the surface of the wafer 10 to form the first layer of atomic thin film 40.

[0077] The positively charged second film-forming byproduct ions 31 are repelled by the electric field away from the wafer 10 surface. At this time, the strength of the second electrostatic field should be adjusted according to the adsorption force of the first film-forming target ions 22 that have been adsorbed on the surface, so as to avoid desorption of the first film-forming target ions 22 under the action of the reverse electric field.

[0078] Step S406: After forming the first layer of atomic thin film 40, and during the introduction of the purge gas into the process chamber, the wafer carrier is controlled to continuously apply the second electrostatic field to the wafer 10 surface, wherein the second electrostatic field is associated with the adsorption force of the first film-forming target ions 22 on the wafer 10 surface.

[0079] For example, referring to Figure 6 During the purging process, the second electrostatic field has the same effect as the first electrostatic field, that is, to anchor the first layer of atomic thin film 40 by the reverse electric field, so as to prevent the film layer from being separated from the wafer 10 surface under the action of the suction force. Here, no more details are given.

[0080] For example, referring to Figure 7 , the first layer of atomic thin film 40 is formed.

[0081] It should be understood that, although Figure 1 the steps in the flowchart are shown in order according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps in may include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0082] For example, referring to Figure 8 , the present application provides an atomic layer deposition control device, comprising a control device for controlling a process chamber to perform N target process steps to deposit a target film layer of a target thickness on the surface of a wafer therein; the control device comprises an excitation source, a wafer carrier, and a controller connected to the excitation source and the wafer carrier, and configured to perform the following steps during the execution of the ith target process step:

[0083] During the process of introducing the first precursor gas atoms 20 into the process chamber, the excitation source is controlled to apply a first magnetic field into the process chamber, and the wafer carrier is controlled to apply a first electrostatic field to the surface of the wafer 10, so that the first film-forming target ions 22 decomposed from the first precursor gas atoms 20 accelerate towards the surface of the wafer 10 and are adsorbed on the surface of the wafer 10.

[0084] During the process of introducing the second precursor gas atoms 30 into the process chamber, the excitation source is controlled to apply a second magnetic field into the process chamber, and the wafer carrier is controlled to apply a second electrostatic field to the surface of the wafer 10, so that the second film-forming target ions 32 decomposed from the second precursor gas atoms 30 accelerate towards the surface of the wafer 10, react with the first film-forming target ions 22 and form the i-th layer of atomic thin film, i∈[1, N], N is a positive integer, for example, N is 1, 2, 3, 4, …, etc.

[0085] For example, by applying a variable longitudinal magnetic field perpendicular to the surface of the wafer 10 in the process chamber, the first precursor gas atoms 20 and the second precursor gas atoms 30, as well as the first film-forming target ions 22 and the second film-forming target ions 32 decomposed by heat, are driven to move rapidly towards the surface of the wafer 10, thereby shortening the time for the film-forming target ions to approach and be adsorbed on the surface of the wafer 10. At the same time, the device forms an electrostatic field on the surface of the substrate by applying an external voltage, accelerates the adsorption of the film-forming target ions on the surface of the wafer 10 by means of electrostatic field-induced adsorption, and enhances the adsorption strength, thereby widening the process temperature window, reducing the probability of desorption in subsequent purging and high-temperature environment, and further shortening the purging time.

[0086] The synergistic effect of the electromagnetic field brings multiple advantages, including shortening the purging and purging time, widening the temperature window, reducing desorption, improving film quality, and being green and environmentally friendly. Benefiting from faster deposition rate and more excellent film performance without introducing other impurities, the production cost is reduced. The uniform and dense film has better electrical, optical and mechanical properties, which widens the application field of ALD technology and enables it to be applied in the fields of flexible electronics, biomedicine and nanotechnology.

[0087] The application also provides a deposition device, comprising a process chamber and the above-mentioned atomic layer deposition control device.

[0088] Benefiting from the improved ALD process, the deposition device can flexibly adjust the direction and strength of the applied magnetic field and electric field according to the decomposition ion electric property state and charge amount of the precursor gas, while maintaining the original film quality, expanding the process temperature window, shortening the film deposition period, and improving the film uniformity. In addition, the electromagnetic field assisted technology also avoids the use of chemical reagents, further reducing environmental pollution. More advanced ALD equipment can provide better quality products and enhance their market competitiveness. In addition, faster ALD deposition rate and better film quality will promote the development and innovation of ALD technology, laying the foundation for the development of new materials and new devices.

[0089] In the above embodiments, the unexpected technical effects of the present application are:

[0090] The present application forms an electrostatic field by applying a variable longitudinal magnetic field perpendicular to the wafer surface inside the cavity and applying a voltage on the substrate surface, accelerates the movement of reaction precursor ions to the wafer surface by the magnetic field / electric field induced adsorption, enhances the adsorption rate and adsorption strength of target film-forming ions on the wafer surface, avoids desorption phenomenon caused by low activity and poor adsorption capacity of the precursor, widens the deposition process temperature window, shortens the deposition period, improves the film deposition uniformity and density, and achieves the purpose of increasing the atomic layer deposition rate and improving the production efficiency.

[0091] In addition to the above advantages, the electromagnetic field assisted atomic layer deposition control method also has the advantages of environmental protection and energy saving, including reducing material consumption, reducing energy consumption, and not introducing impurities, avoiding the use of chemical reagents, and further reducing environmental pollution.

[0092] Uniform and dense films have better electrical, optical and mechanical properties, widening the application field of ALD technology and meeting the harsh requirements of different application fields; promoting the development and innovation of ALD technology, laying the foundation for the development of new materials and new devices.

[0093] The technical features of the above embodiments can be combined arbitrarily. In order to make the description simple, not all possible combinations of the technical features of the above embodiments are described, but as long as the combination of these technical features does not exist contradictory, it should be considered as the scope of the description.

[0094] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An atomic layer deposition control method, characterized by, A method for controlling a process chamber to perform N target process steps to deposit a target film layer of a target thickness on a wafer surface in the process chamber, wherein performing an i-th target process step comprises: controlling a magnetization source to apply a first magnetic field in the process chamber while controlling a wafer chuck to apply a first electrostatic field to the wafer surface during a period when a first precursor gas is introduced into the process chamber, so that first film-forming target ions decomposed from the first precursor gas accelerate toward the wafer surface and are adsorbed on the wafer surface; controlling the magnetization source to apply a second magnetic field in the process chamber while controlling the wafer chuck to apply a second electrostatic field to the wafer surface during a period when a second precursor gas is introduced into the process chamber, so that second film-forming target ions decomposed from the second precursor gas accelerate toward the wafer surface, react with the first film-forming target ions, and form an i-th layer of atomic thin film, i ∈ [1, N].

2. The atomic layer deposition control method according to claim 1, characterized by The performing the i-th target process step further comprises: controlling the wafer chuck to continuously apply the first electrostatic field to the wafer surface before the second precursor gas is introduced into the process chamber and during a period when a purge gas is introduced into the process chamber.

3. The atomic layer deposition control method according to claim 1, characterized by, The performing the i-th target process step further comprises: controlling the wafer chuck to continuously apply the second electrostatic field to the wafer surface after the first layer of atomic thin film is formed and during a period when the purge gas is introduced into the process chamber, wherein the second electrostatic field is associated with an adsorption force of the first film-forming target ions on the wafer surface.

4. The atomic layer deposition control method of claim 1, wherein The first film-forming target ions and the second film-forming target ions have opposite electric properties.

5. The atomic layer deposition control method of claim 1, wherein The first precursor gas decomposes first film-forming target ions and first film-forming byproduct ions at the same time, and the first film-forming target ions and the first film-forming byproduct ions have opposite electric properties.

6. The atomic layer deposition control method of claim 1, wherein The second precursor gas decomposes second film-forming target ions and second film-forming byproduct ions at the same time, and the second film-forming target ions and the second film-forming byproduct ions have opposite electric properties.

7. An atomic layer deposition control apparatus, characterized by, A control device for controlling a process chamber to perform N target process steps to deposit a target film layer of a target thickness on a wafer surface in the process chamber, wherein the control device comprises: a magnetization source; a wafer chuck; and a controller connected to the magnetization source and the wafer chuck, and configured to perform the following steps during an i-th target process step: controlling the magnetization source to apply a first magnetic field in the process chamber while controlling the wafer chuck to apply a first electrostatic field to the wafer surface during a period when a first precursor gas is introduced into the process chamber, so that first film-forming target ions decomposed from the first precursor gas accelerate toward the wafer surface and are adsorbed on the wafer surface; During the period of introducing the second precursor gas into the process chamber, the controller controls the excitation source to apply a second magnetic field into the process chamber while controlling the wafer carrier to apply a second electrostatic field to the wafer surface, so that second film-forming target ions decomposed from the second precursor gas accelerate toward the wafer surface, react with the first film-forming target ions, and form an i-th layer of atomic thin film, i∈[1, N].

8. The atomic layer deposition control apparatus according to claim 7, characterized by The controller further performs the following steps during the execution of the i-th target process step: Before introducing the second precursor gas into the process chamber, and during the period of introducing the purge gas into the process chamber, the controller controls the wafer carrier to continuously apply the first electrostatic field to the wafer surface.

9. The atomic layer deposition control apparatus according to claim 7, characterized by The controller further performs the following steps during the execution of the i-th target process step: After forming the first layer of atomic thin film, and during the period of introducing the purge gas into the process chamber, the controller controls the wafer carrier to continuously apply the second electrostatic field to the wafer surface, wherein the second electrostatic field is associated with the adsorption force of the first film-forming target ions on the wafer surface.

10. A deposition apparatus, characterized by, Comprise: a process chamber; and an atomic layer deposition control device according to any one of claims 7-9.

Images