Ion beam processing chamber and ion etching apparatus

Abstract

The application discloses an ion beam process chamber and an ion etching device, and relates to the technical field of ion beam etching, in particular to an ion beam process chamber and an ion etching device. The ion beam process chamber comprises an ion chamber, a reaction chamber, a wafer carrier and a restraint plate. The ion chamber has an ion source, and the joint between the ion chamber and the reaction chamber is a spraying port. The ion source forms an ion beam in the reaction chamber through the spraying port. The wafer carrier is arranged in the reaction chamber. The restraint plate is arranged at the spraying port to adjust the bombardment angle of the ion beam. The ion beam process chamber of the application is provided with the restraint plate at the spraying port. The bombardment area of the ion beam can be adjusted by adjusting the bombardment angle of the ion beam through the restraint plate, so that the probability of bombarding the reaction chamber is reduced. In addition, the restraint plate is made of non-metal material, so that no metal is ionized, and the metal and particle pollution caused by the process is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing technology, and in particular to an ion beam process chamber and ion etching equipment. Background Technology

[0002] In ion etching equipment, during the process, the plasma beam process chamber is bombarded by ion beams, which introduces trace element contamination such as Al, Fe, and Cr, as well as non-vaporized solid particle contamination based on metal elements, thus affecting the stability of the wafer process.

[0003] Therefore, how to improve the stability of wafer fabrication processes has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] This invention proposes an ion beam process chamber and ion etching equipment to improve the stability of wafer processing.

[0005] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides an ion beam process chamber, comprising an ion chamber, a reaction chamber, a wafer stage, and a restraining plate, wherein the ion chamber has an ion source, and the junction with the reaction chamber is a jet port, through which the ion source forms an ion beam within the reaction chamber; the wafer stage is arranged within the reaction chamber; and the restraining plate is arranged at the jet port to adjust the bombardment angle of the ion beam.

[0006] In some embodiments, the restraint plate is made of a non-metallic material.

[0007] In some embodiments, the injection nozzle is a circular hole; the restraint plate is an annular structure.

[0008] In some embodiments, the restraint plate is any one of a circular ring structure, a rectangular ring structure, and an elliptical ring structure.

[0009] In some embodiments, the restraint plate is detachably connected to the injection nozzle.

[0010] In some embodiments, the restraint plate is detachably disposed at the injection port via fasteners.

[0011] In some embodiments, the fasteners are made of non-metallic materials.

[0012] In some embodiments, the restraint plate is slidably disposed at the injection port.

[0013] In some embodiments, the ion beam process chamber further includes a drive, a transmission, and a slide rail. The slide rail extends along the width of the jet nozzle, and a restraint plate is slidably disposed on the slide rail. The drive drives the restraint plate to slide on the slide rail via the transmission.

[0014] In some embodiments, the transmission components and slide rails are made of non-metallic materials.

[0015] In some embodiments, the restraint plate includes a substrate with an opening and at least two sliding blades slidably arranged at the opening of the substrate to adjust the size of the opening.

[0016] In some embodiments, the restraint plate also includes a flexible rope that passes sequentially through at least two sliding blades to pull the sliding blades and adjust the size of the opening.

[0017] In some embodiments, the reaction chamber is provided with a non-metallic liner or is coated with a non-metallic liner within the ion beam bombardment area.

[0018] In some embodiments, the outer periphery of the wafer stage is provided with a non-metallic liner or is coated with a non-metallic liner.

[0019] In some embodiments, the outer periphery of the wafer stage is provided with a non-metallic liner or is coated with a non-metallic liner.

[0020] In some embodiments, an adsorption sleeve is provided around the electrostatic adsorption disk of the wafer stage. The adsorption sleeve is made of non-metallic material or is coated with non-metallic material.

[0021] In some embodiments, the adsorption sleeve is a tubular structure that is fitted around the outer periphery of the electrostatic adsorption disk; or the adsorption sleeve is made of a flexible non-metallic material wound together.

[0022] In some embodiments, the adsorption sleeve also includes an edge that extends from the adsorption sleeve to the outer periphery, and the edge is made of a non-metallic material or is coated with a non-metallic material.

[0023] In some embodiments, the non-metallic material is graphite, quartz, SiC, or PTFE.

[0024] Secondly, this application provides an ion etching apparatus including an ion beam process chamber as described in any of the above.

[0025] As can be seen from the above technical solution, the ion beam process chamber of this application is provided with a restraining plate at the nozzle. By adjusting the bombardment angle of the ion beam, the bombardment area of ​​the ion beam can be adjusted, thereby reducing the probability of bombarding the reaction chamber.

[0026] In addition, the binding plate is made of non-metallic material, so it will not release metal, thus reducing metal and particulate pollution during the process. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort, and the present invention can be applied to other similar scenarios based on the provided drawings. Unless obvious from the linguistic context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0028] Figure 1 This is a schematic diagram of an ion beam process chamber provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of another ion beam process chamber provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of a jet nozzle and a restraint plate in cooperation, provided in an embodiment of the present invention. Figure 4 This is a schematic diagram illustrating another possible combination of a jet nozzle and a restraint plate provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the third type of injection port and restraint plate provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the fourth type of injection port and restraint plate provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of a third type of ion beam process chamber provided in an embodiment of the present invention; Figure 8 A schematic diagram of an outer liner provided in an embodiment of the present invention; Figure 9 and Figure 10 This is a schematic diagram of the fourth type of ion beam process chamber provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of an adsorption sleeve provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of another adsorption sleeve provided in an embodiment of the present invention; In the diagram, 1-ion chamber; 2-reaction chamber; 3-wafer stage; 4-binding plate; 5-inner liner; 6-outer liner; 7-adsorption sleeve; 8-edge; 11-jet nozzle; 41-substrate; 42-opening; 43-blade; 44-flexible rope. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. The described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] Integrated circuits, as the foundation and core of the information industry, include the central control unit (CPU) composed of semiconductor chips, which is widely used in various everyday products such as medical devices, automobiles, and mobile phones, playing an increasingly important role in people's lives. With the reduction in CPU feature size, the decrease in depth of focus in lithography equipment, and the trend towards 3D stacking of chip structures during the manufacturing process of very large-scale integrated circuits (VLSI), more stringent requirements and challenges have been placed on the microscopic correction and planarization processes of the wafer chip morphology that form the CPU. Currently, for devices with a minimum feature size of 0.35 micrometers or less, chemical mechanical polishing (CMP) is the mainstream technology for achieving silicon wafer planarization. However, with the development of advanced technology nodes (above 22nm) and the emergence of new integration processes, such as the replacement of metal gates (RMG), self-aligned contacts (SAC), and polysilicon aperture CMP, more challenges have been posed to the thickness and morphological uniformity of the chip structure (up to the nanometer or even angstrom level). Furthermore, improper process control in CMP contact processing can lead to substrate defects, and particle contamination induced by the polishing slurry can limit its application and reduce yield. Furthermore, CMP technology currently cannot achieve high-precision planarization control at the nanometer or angstrom level, making it difficult to perform highly uniform and precise machining of the replacement metal gate (RMG) for 3D transistor structure (FinFET) nodes. These inherent limitations of CMP processes restrict their application in advanced manufacturing processes where chip dimensions are constantly shrinking.

[0031] Ion beam etching (IBE) and flexible shaping etching (FSE) techniques for particle beam shaping (IBS) of chip structures, such as micromachining and planarization, represent the latest developments in dry etching technology and offer new opportunities for precise control of chip thickness at the nanometer scale. This technology uses an ion source to bombard the wafer surface with neutral gas ions of a certain energy, removing or selectively removing surface material through physical sputtering. By optimizing the particle beam (energy, beam density, etc.) during the process, the IBS process can effectively control the movement of colliding particles, achieving ultra-precision machining of atomically flat surfaces. By controlling the particle beam pulled out by the ion source during IBE / FSE, the incident angle of the bombarding ions can be adjusted, giving IBS a unique advantage in directional etching for surface micromachining, thus achieving different etching rates at different incident ion bombardment angles on specific material surfaces. These characteristics enable IBS based on IBE / FSE technology to modify the surface roughness of chip patterns, truly achieving nanometer-level cross-wafer uniformity and planarity control (3σ<15A within a 300mm wafer), meeting the stringent in-wafer uniformity targets of FinFET and even Gate All Around (GAA) transistor technologies. Furthermore, by adjusting the particle beam energy and bombardment angle, IBS can correct the shape and arrangement of EUV-generated chip patterns in the extreme ultraviolet (EUV) patterning process of chip manufacturing, replacing multiple EUV patterning processes, reducing the number of double or multiple EUV exposures, simplifying the processing flow of small-size, high-precision chips, improving production efficiency, and reducing costs. Therefore, IBE and FSE technologies are finding increasingly important applications in advanced manufacturing processes such as the miniaturization of advanced logic chip process nodes and the trend towards 3D memory chips.

[0032] To achieve good etching uniformity, current IBE and IBS ion etching equipment utilizes ion beam process chambers, such as... Figure 1 As shown, the ion beam generated by ion chamber 1 has a bombardment angle of approximately 10°, resulting in a bombardment area that includes the wafer surface, the wafer stage 3 that holds the wafer, and the inner wall of reaction chamber 2. When the wafer stage 3 and the inner wall of reaction chamber 2 contain aluminum alloy or stainless steel components, the surface of the wafer stage 3 will be contaminated with trace elements such as Al, Fe, and Cr (>Spec: 1E10at. / cm²) and non-vaporized solid particles based on metal elements during the ion beam bombardment process. The generation of these contaminants affects the stability of the wafer process and greatly limits the application of IBS and IBE ion etching equipment and processes in high-end chip manufacturing.

[0033] To address the aforementioned technical problems, this application primarily focuses on reducing the bombardment area of ​​the ion beam. An ion beam process chamber is disclosed in this embodiment of the invention.

[0034] See Figure 2 The ion beam process chamber disclosed in this application includes an ion chamber 1, a reaction chamber 2, a wafer stage 3, and a restraining plate 4. The ion chamber 1 has an ion source, and its connection to the reaction chamber 2 is a jet nozzle 11. The ion source forms an ion beam within the reaction chamber 2 through the jet nozzle 11. The wafer stage 3 is disposed within the reaction chamber 2. The restraining plate 4 is disposed at the jet nozzle 11 to adjust the bombardment angle of the ion beam. The ion beam process chamber of this application has a confinement plate 4 at the nozzle 11. The confinement plate 4 can be used to adjust the bombardment area of ​​the ion beam by adjusting the bombardment angle of the ion beam, thereby reducing the probability of bombarding the reaction chamber 2.

[0035] The binding plate 4 is made of non-metallic material, so it will not release metal, reducing metal and particulate pollution during the process.

[0036] The confinement plate 4 is set at the nozzle 11. By adjusting the size of the confinement plate 4 extending out of the nozzle 11, the opening size of the nozzle 11 can be adjusted, which is equivalent to adjusting the bombardment angle of the ion beam.

[0037] In addition, since the binding plate 4 is made of non-metallic material, the area bombarded by the ion beam will not generate trace element pollution or non-gasified solid particle pollution based on metallic elements.

[0038] Furthermore, the binding plate 4 is made of non-metallic materials such as graphite, quartz, SiC, and PTFE.

[0039] In the etching environment of IBE and IBS processes, the above-mentioned materials can undergo a chemical reaction with the reactive gases, forming gases that are then released. For example: Graphite: C + O₂ → CO₂ (g) Quartz: SiO2 + 2CF4 → SiF4(g) + 2CO2(g) SiO2 + NF3 + O2 → NO2 + SiF4(g) SiC: SiC + 2O2 → SiO2(s) + CO2 Preferably, the binding plate 4 is made of graphite, which has low sputtering yield. Graphite has high thermal conductivity, high chemical stability, and corrosion resistance. After purification, the ash content of the graphite can be controlled below 5 ppm. The high-purity graphite liner, produced by chemical cleaning, can effectively eliminate metal element contamination caused by ion beam bombardment and reduce particle generation, making it the preferred material.

[0040] See Figures 3 to 4 The injection port 11 is a circular hole, and the binding plate is a ring structure, which can be a circular ring structure, a rectangular ring structure, or an elliptical ring structure. Figure 3 The middle binding plate 4 has a circular ring structure. Figure 4 The middle binding plate 4 is a rectangular ring structure.

[0041] The length of the restraint plate 4 extending out of the spray nozzle 11 is adjustable; for example, the restraint plate 4 and the spray nozzle 11 can be detachably connected or slidably connected. The restraint plate 4 adheres to the spray nozzle 11 solely by its own weight without the aid of other components.

[0042] When the restraint plate 4 is detachably connected to the injection port 11, the restraint plate 4 is detachably mounted on the injection port 11 by fasteners. When it is necessary to install the restraint plate 4, the restraint plate is installed on the injection port 11 by fasteners.

[0043] Fasteners can be metal or non-metal. In particular, when they are non-metallic, it can reduce the amount of metal released and reduce metal and particulate contamination during the process.

[0044] In some examples, the restraint plate 4 is slidably disposed at the nozzle 11. The ion beam process chamber also includes a drive, a transmission, and a slide rail. The slide rail extends along the width direction of the nozzle 11. The restraint plate 4 is slidably disposed on the slide rail. The drive drives the restraint plate 4 to slide on the slide rail through the transmission.

[0045] In some embodiments, the transmission components and slide rails are made of non-metallic materials, which can reduce the release of metal and reduce metal and particulate contamination during the process.

[0046] See Figure 5 and Figure 6 This application also discloses a restraint plate 4, which includes a substrate 41 with an opening 42 and at least two sliding blades 43. The sliding blades 43 are slidably arranged at the opening 42 of the substrate 41 to adjust the size of the opening 42. By stretching the sliding blades 43, the length of the sliding blades 43 extending into the opening 42 can be adjusted, thereby adjusting the size of the opening 42 and further adjusting the bombardment area of ​​the ion beam.

[0047] The diagram shows four sliding blades 43. In some examples, the number of sliding blades 43 may be two, three, five, etc.

[0048] In addition, for easy adjustment, the aforementioned restraint plate 4 also includes a flexible rope 44, which passes through at least two sliding blades 43 in sequence to pull the sliding blades 43 and adjust the size of the opening 42. The adjusting blade can be pulled out by pulling the flexible rope 44, thereby adjusting the size of the opening 42.

[0049] It should be noted that the aforementioned substrate 41, sliding blade 43, and flexible rope 44 are all made of non-metallic materials.

[0050] This application can also reduce the use of metallic materials in the bombardment area, thereby reducing pollution. In some examples, the reaction chamber 2 is provided with a non-metallic liner 5 or is coated with a non-metallic material in the bombardment area of ​​the ion beam.

[0051] As described above, the lining 5 made of non-metallic material or coated with a non-metallic material can chemically react with the reactive gas in the etching environment of IBE and IBS processes, forming gas that is then discharged without causing pollution.

[0052] See Figure 7 and Figure 8 In the above examples, the lining 5 is mainly arranged in the areas of the inner wall of the reaction chamber 2 that can be bombarded, that is, the lining 5 is arranged in key areas. On the one hand, this can effectively reduce the generation of pollution, and on the other hand, it can reduce the improvement cost. In some other examples of this application, the entire interior of the reaction chamber 2 is arranged with the lining 5.

[0053] As described above, since the shell wall of the wafer stage 3 is made of metal, in some examples of this application, the outer periphery of the wafer stage 3 is provided with a non-metallic outer liner 6 or coated with a non-metallic outer liner 6. Similarly, using a non-metallic outer liner 6 or coating with a non-metallic outer liner 6 can further reduce the generation of contaminants.

[0054] It should be noted that the outer liner 6 is a barrel-shaped structure, fitted around the outer periphery of the wafer stage 3; or the outer liner 6 is made of a non-metallic flexible material wound together.

[0055] See Figures 9 to 12 To further optimize the above solution, an adsorption sleeve 7 is also provided around the electrostatic adsorption tray of the wafer stage 3. The adsorption sleeve 7 is made of non-metallic material or is coated with non-metallic material. Using the above-mentioned adsorption sleeve 7 can reduce the generation of contamination in this area.

[0056] It should be noted that the aforementioned adsorption sleeve 7 is a tubular structure, fitted around the outer periphery of the electrostatic adsorption disk; or the adsorption sleeve is made of a non-metallic flexible material wound together.

[0057] In addition, the adsorption sleeve 7 also includes an edge 8, which extends outward from the adsorption sleeve 7. The edge 8 is made of non-metallic material or is coated with non-metallic material. By setting the edge 8, the ion beam can be blocked from bombarding the inner liner 5.

[0058] This application provides an ion etching apparatus including an ion beam process chamber as described above. Since the aforementioned ion beam process chamber has the above-mentioned beneficial effects, the ion etching apparatus including this ion beam process chamber also has corresponding effects, which will not be elaborated further here.

[0059] In the above context, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0060] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed, and is not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. The scope of the invention is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in the present invention.

Claims

1. An ion beam process chamber, characterized in that, The device includes an ion chamber, a reaction chamber, a wafer stage, and a restraining plate. The ion chamber has an ion source, and the connection point with the reaction chamber is a jet nozzle. The ion source forms an ion beam in the reaction chamber through the jet nozzle. The wafer stage is arranged in the reaction chamber. The restraining plate is arranged at the jet nozzle to adjust the bombardment angle of the ion beam.

2. The ion beam process chamber as described in claim 1, characterized in that, The restraint plate is made of non-metallic material.

3. The ion beam process chamber as described in claim 1, characterized in that, The injection port is a circular hole; the restraint plate is a ring-shaped structure.

4. The ion beam process chamber as described in claim 3, characterized in that, The binding plate can be any one of a circular ring structure, a rectangular ring structure, or an elliptical ring structure.

5. The ion beam process chamber as described in claim 1, characterized in that, The restraint plate is detachably connected to the injection port.

6. The ion beam process chamber as described in claim 5, characterized in that, The restraint plate is detachably mounted at the injection port via fasteners.

7. The ion beam process chamber as described in claim 6, characterized in that, The fasteners are made of non-metallic material.

8. The ion beam process chamber as described in claim 1, characterized in that, The restraint plate is slidably disposed at the injection port.

9. The ion beam process chamber as described in claim 8, characterized in that, The ion beam process chamber further includes a drive unit, a transmission unit, and a slide rail. The slide rail extends along the width direction of the jet nozzle. The restraint plate is slidably disposed on the slide rail. The drive unit drives the restraint plate to slide on the slide rail through the transmission unit.

10. The ion beam process chamber as described in claim 9, characterized in that, The transmission components and slide rails are made of non-metallic materials.

11. The ion beam process chamber as described in claim 1, characterized in that, The restraint plate includes a base plate with an opening and at least two sliding blades, the sliding blades being slidably arranged at the opening of the base plate to adjust the size of the opening.

12. The ion beam process chamber as described in claim 11, characterized in that, The restraint plate also includes a flexible rope that passes sequentially through at least two of the sliding blades to pull the sliding blades and adjust the size of the opening.

13. The ion beam process chamber as described in claim 1, characterized in that, The reaction chamber is lined with a non-metallic material or coated with a non-metallic material within the bombardment area of ​​the ion beam.

14. The ion beam process chamber as described in claim 1, characterized in that, The outer periphery of the wafer stage is provided with a non-metallic liner or is coated with a non-metallic liner.

15. The ion beam process chamber as described in claim 14, characterized in that, The outer liner is a barrel-shaped structure, fitted around the outer periphery of the wafer stage; or the outer liner is made of a flexible non-metallic material wound together.

16. The ion beam process chamber as described in claim 1, characterized in that, The periphery of the electrostatic adsorption disk of the wafer stage is provided with an adsorption sleeve, which is made of non-metallic material or is coated with non-metallic material.

17. The ion beam process chamber as described in claim 16, characterized in that, The adsorption sleeve is a tubular structure and is fitted around the outer periphery of the electrostatic adsorption disk; or the adsorption sleeve is made of a flexible non-metallic material wound together.

18. The ion beam process chamber as described in claim 17, characterized in that, The adsorption sleeve also includes an edge that extends outward from the adsorption sleeve, and the edge is made of non-metallic material or coated with non-metallic material.

19. The ion beam process chamber according to any one of claims 2 to 18, characterized in that, The non-metallic materials are graphite, quartz, SiC, and PTFE.

20. An ion etching apparatus, characterized in that, Includes the ion beam process chamber as described in any one of claims 1 to 19.

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