Gas supply device and etching machine
By designing a multi-zone air intake ring and an independent control valve on the etching machine, the non-uniformity problem outside the wafer center area is solved, achieving higher etching uniformity and film thickness consistency, which is suitable for etching processes in integrated circuit manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SIEN (QINGDAO) INTEGRATED CIRCUITS CO LTD
- Filing Date
- 2025-07-11
- Publication Date
- 2026-06-12
AI Technical Summary
In traditional techniques, the uniformity optimization of the etching equipment in the central region of the wafer cannot completely cover the edges or special locations, resulting in non-uniformity problems. In particular, under low-temperature deposition processes, problems such as uneven film thickness and edge warping deformation are prominent.
Design a gas supply device with an intake ring divided into multiple regions, each equipped with an independent control valve. By adjusting the opening or closing of the gas passage through the control valve, the position of the tuning gas entering the etching chamber can be precisely controlled. Combined with the gradually expanding structure of the guide element and the independent guide channel, uniform gas distribution can be achieved.
It solves the asymmetry problem caused by the low-temperature deposition process and the non-uniformity of the front layer film thickness on the wafer, improves the uniformity and accuracy of the etching process, and reduces the non-uniformity problem in the edge region.
Smart Images
Figure CN224355221U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of integrated circuit manufacturing technology, and in particular to a gas supply device and an etching machine. Background Technology
[0002] As the critical dimensions of integrated circuit technology nodes continue to shrink, higher demands are being placed on etching performance. Uniformity is a crucial quality metric in semiconductor manufacturing processes, especially etching (ETCH) and lithography (LITHO), which typically require high in-plane uniformity to achieve precise linewidth control. Beyond the recipe's architecture, the equipment itself is constantly being optimized to provide engineers with more methods to improve uniformity.
[0003] In traditional techniques, edge gas tuning is an effective method to adjust uniformity. By injecting clean gas or polymer gas at the wafer edge, the chemical balance of edge etching can be controlled.
[0004] In current semiconductor etching processes, the core approach to improving uniformity focuses on optimizing the wafer centering region. However, in actual production, in addition to centering, there may be non-uniformity issues at edges or special locations, and traditional centering optimization cannot fully cover such areas. Utility Model Content
[0005] The purpose of this application is to provide a gas supply device and an etching machine to overcome the problem that the core means of improving uniformity in traditional technologies are concentrated in the central area of the wafer, and cannot completely cover areas such as the edges or special locations.
[0006] In a first aspect, this application provides a gas supply device for use in an etching machine, the etching machine including an etching cavity, in which a wafer to be processed is placed; the gas supply device includes: an air inlet ring, a gas supply system, and a control valve;
[0007] The intake ring is connected to the air supply system;
[0008] The intake ring is provided with multiple regions along the circumference; each region is provided with multiple air passages along the circumference.
[0009] Each of the areas is provided with a control valve, which is used to control the opening or closing of each air passage in the area.
[0010] In one embodiment, each of the regions is provided with a flow guide, and the flow guide has the air passage.
[0011] In one embodiment, the regions are evenly distributed on the intake ring, and the air passages are evenly distributed within the regions.
[0012] In one embodiment, the outlet side of the air guide adopts a gradually expanding structure.
[0013] In one embodiment, each region of the intake ring is provided with an arc-shaped opening.
[0014] In one embodiment, the air intake ring is provided with an air intake pipe, and the air supply system supplies air to each of the air passages through the air intake pipe.
[0015] In one embodiment, the gas supply system includes a first gas supply pipe and a second gas supply pipe; the first gas supply pipe and the second gas supply pipe are respectively connected to the air inlet pipe; a first switching valve is provided on the first gas supply pipe, and a second switching valve is provided on the second gas supply pipe, and the control signals of the first switching valve and the second switching valve are opposite.
[0016] In one embodiment, the air intake ring is disposed at the top of the etching cavity.
[0017] In one embodiment, the control valve is a flow control valve.
[0018] Secondly, this application also provides an etching apparatus, comprising:
[0019] Etching cavity;
[0020] An electrostatic chuck is disposed within the etching cavity to fix the wafer to be processed;
[0021] The gas supply device described in any one of the first aspects above is partially disposed on the top of the electrostatic chuck for outputting tuning gas to the edge region of the wafer to be processed.
[0022] The aforementioned gas supply device and etching machine have at least the following advantages:
[0023] The gas supply device of this application sets the air intake ring into multiple regions, each region is equipped with multiple air channels, and each region is equipped with a control valve. In this way, for each region, all or part of the air channels can be opened, thereby precisely controlling the position of the tuning gas entering the etching cavity. This solves to some extent the asymmetry problem caused by the low temperature deposition process of the front layer and the problem of uneven film thickness of the front layer of the wafer. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of an etching machine in traditional technology;
[0025] Figure 2 This is a schematic diagram of the structure of an air supply component in traditional technology;
[0026] Figure 3 This is a schematic diagram of the gas supply device in one embodiment;
[0027] Figure 4 This is a schematic diagram of the gas supply system in one embodiment;
[0028] Figure 5 This is a structural schematic diagram of a region of the intake ring in one embodiment;
[0029] Figure 6 This is a schematic diagram of gas flow in different regions of one embodiment;
[0030] Figure 7 This is a schematic diagram of gas flow in different regions in another embodiment.
[0031] Figure label:
[0032] 1. Etching chamber; 2. Wafer; 3. Electrostatic chuck; 4. Gas supply device; 5. Exhaust port; 6. Inlet ring;
[0033] 7. Control valve; 8. Flow guide. Detailed Implementation
[0034] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.
[0035] 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 herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0036] When using the terms “including,” “having,” and “comprising” as described herein, another component may be added unless explicitly qualifying terms such as “only,” “consisting of,” etc. are used. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.
[0037] It should be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of this application, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.
[0038] In this application, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal connection of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0039] Please see Figure 1 In traditional technology, the etching machine includes an etching chamber, an electrostatic chuck (ESC) 3, an air supply component 4, and an exhaust port 5.
[0040] The electrostatic chuck 3 is located inside the etching chamber. During the etching process of wafer 2, wafer 2 is placed on the electrostatic chuck 3, which uses electrostatic force to attract and fix wafer 2, avoiding contamination caused by physical contact. Furthermore, the electrostatic chuck 3 is also used to maintain the surface temperature uniformity of wafer 2 through back helium gas and a multi-zone temperature control system; furthermore, the electrostatic chuck 3 also serves as part of the electrode, transferring radio frequency energy to the plasma to control the etching rate and directionality.
[0041] The gas supply component 4 is located inside the etching chamber and at the top of the etching chamber. An air inlet channel is inserted through the top of the etching chamber. One end of the air inlet pipe is connected to the gas supply component 4 inside the etching chamber, and the other end of the air inlet pipe is connected to an external gas supply system for introducing clean gas or polymer gas into the gas supply component 4.
[0042] The exhaust port 5 is located at the bottom of the etching chamber and is connected to the vacuum pump. The exhaust port 5 is also equipped with a swing valve, which is used to extract the reaction gas in the etching chamber when the swing valve is open, so as to maintain the stability of the vacuum environment in the etching chamber.
[0043] In wafer 2 edge tuning, if the front layer uses LT / DEP (Low Temperature Deposition) technology, asymmetry problems may arise. Specifically, LT (low temperature) refers to a deposition process performed at a relatively low temperature (e.g., <300°C), often used for the fabrication of sensitive materials (such as organic thin films, certain metals, or dielectric layers) to avoid damage to the underlying structure from high temperatures. DEP (deposition) refers to the process of forming a thin film on the surface of wafer 2 using techniques such as chemical vapor deposition (CVD), physical vapor deposition (PVD), or atomic layer deposition (ALD). At low temperatures, the deposition rate is slower and the reaction kinetics are limited, which can easily lead to uneven distribution of film thickness or composition between the edge and center regions of wafer 2. In addition, the film deposited at low temperatures may generate local stress due to the mismatch of thermal expansion coefficients, resulting in warping or deformation of the wafer 2 edge. Low temperature deposition may also lead to weaker adhesion between the film and the substrate interface, making the edge region more susceptible to peeling or microcracks during plasma etching.
[0044] Please see Figure 2 , Figure 2 The diagram shows a typical gas supply component 4. This component 4 is annular and has multiple evenly distributed air inlets. Cleaning gas or polymer gas enters the etching chamber evenly through these inlets. With this structure, if the preceding layer uses the aforementioned LT / DEP process, the uniform air supply method will be unable to solve the non-uniformity problem in the edge areas during subsequent etching processes.
[0045] Please see Figure 3 Based on this, in one embodiment, a gas supply device is provided, which is applied to the above-mentioned etching machine and includes: an air inlet ring 6, a gas supply system and a control valve 7.
[0046] An air intake ring 6 is disposed within the etching chamber of the etching machine and is located at the top of the etching chamber. The air intake ring 6 is connected to the air supply system and receives tuning gas provided by the air supply system, which includes cleaning gas and polymer gas.
[0047] Furthermore, an intake pipe is provided on the intake ring 6, and the intake ring 6 is connected to the air supply system through the intake pipe.
[0048] Please see Figure 4 Optionally, the gas supply system includes a first gas supply pipeline and a second gas supply pipeline.
[0049] The first and second gas supply pipes are respectively connected to the aforementioned air intake pipe, for example. Figure 4The pipe at the upper end is designated as the first gas supply pipe, and the pipe at the lower end is designated as the second gas supply pipe. Clean gas is sequentially fed into the intake ring 6 through the first gas supply pipe and the intake pipe; polymer gas is sequentially fed into the intake ring 6 through the second gas supply pipe and the intake pipe.
[0050] Optionally, a first switching valve is installed on the first gas supply pipeline, and a second switching valve is installed on the second gas supply pipeline, with the control signals of the first and second switching valves being opposite. With this structure, the gas supply system can provide clean gas through the first gas supply pipeline or polymer gas through the second gas supply pipeline.
[0051] Please see Figure 3 The intake ring 6 has multiple regions along its circumference. For example, in this embodiment, the intake ring 6 has six regions, as shown in the front view of the intake ring 6 after it is unfolded. Figure 3 The six connected rectangular structures shown.
[0052] Optionally, the aforementioned regions are evenly distributed along the circumference. This structure allows the tuning gas to uniformly cover the intake ring 6.
[0053] To further explain, each region has multiple air channels along the circumference. During the etching process of wafer 2, the tuning gas input by the gas supply system flows into the etching cavity through each air channel.
[0054] Optionally, each region of the intake ring 6 is provided with multiple intake holes evenly distributed along the circumferential direction, and in this case, each intake hole constitutes the aforementioned air passage.
[0055] A control valve 7 is connected to the intake ring 6, and each region of the intake ring 6 is equipped with a control valve 7. This control valve 7 controls the opening or closing of the air passages within its region. With intake holes evenly distributed across each region of the intake ring 6, adjusting the control valve 7 allows tuning gas to enter the etching chamber through one or more intake holes in the region corresponding to that control valve 7, thereby controlling the entry position of the tuning gas. Furthermore, the control valves 7 in each region are independent of each other; that is, by adjusting different control valves 7, the air passages in one or more regions can be selected.
[0056] Optionally, the control valve 7 is a flow control valve 7. That is, the opening size of the control valve 7 is adjustable. For example, in this embodiment, the control valve 7 is a split valve, that is, the two valve plates of the control valve 7 can move relative to or away from each other, thereby adjusting the opening size. In actual use, other suitable models of flow control valves 7 can also be selected as needed, such as vacuum needle valves, diaphragm valves, piezoelectric valves, proportional valves, metal-sealed butterfly valves, etc.
[0057] Alternatively, in another embodiment, each region of the intake ring 6 may also be configured as a complete arc-shaped opening. See also... Figure 5, Figure 5 This is a bottom view of a region of the intake ring 6. The arc-shaped opening and control valve 7 together form the aforementioned air passage. The size of the air passage can be adjusted by regulating the opening of control valve 7.
[0058] The aforementioned gas supply device sets the air intake ring 6 into multiple regions, each region having multiple air channels, and each region is equipped with a control valve 7. The opening size of the control valve 7 is adjustable. In this way, for each region, all or part of the air channels can be opened, thereby precisely controlling the position of the tuning gas entering the etching cavity. This solves to some extent the asymmetry problem caused by the use of LT / DEP process in the front layer and the problem of uneven film thickness in the front layer of the wafer.
[0059] Please see Figure 3 Optionally, in one embodiment, the above-mentioned gas supply device further includes a flow guide 8.
[0060] The flow guide 8 is connected to the control valve 7 in each area, and the flow guide 8 has the aforementioned multiple air passages.
[0061] Specifically, the guide element 8 includes multiple independent guide channels. When multiple air inlets are provided in each region of the intake ring 6, each guide channel corresponds to one air inlet, forming the aforementioned air passage. When an arc-shaped opening is provided in each region of the intake ring 6, the arc-shaped opening and each guide channel form the aforementioned air passage. After the tuning gas enters a region of the intake ring 6, it enters the etching chamber from one or more guide channels according to the opening status of the control valve 7. Through the guidance of each guide channel, the gas introduction position can be precisely controlled.
[0062] Optionally, the aforementioned flow channels are uniformly distributed along the circumference of each region. This structure allows the tuning gas to be uniformly distributed to the corresponding positions within the etching cavity via the flow channels.
[0063] Please see Figure 3 and Figure 6 For example, in this embodiment of the application, the flow guide 8 includes six independent and uniformly distributed flow guide channels, such as... Figure 3 As shown, the guide channels are numbered from left to right as the first guide channel to the sixth guide channel. With this structure, after the tuning gas enters the intake ring 6 through the intake pipe, if the control valve 7 of a certain area is completely closed, the tuning gas will not be able to enter the etching chamber through that area; if the control valve 7 of a certain area is partially open, the tuning gas enters the etching chamber through the second and third guide channels; if the control valve 7 of a certain area is completely open, the tuning gas enters the etching chamber simultaneously through all six guide channels.
[0064] For example, when the intake ring 6 is evenly divided into six regions along its circumference, six control valves 7 are also configured accordingly. Each control valve 7 operates independently, thus opening or closing one or more regions of the intake ring 6. Figure 6 As shown, the regions from left to right are labeled as Region 1 to Region 6, and the corresponding control valves 7 for each region are labeled as Control Valve 1 to Control Valve 6. With this structure, partially opening the first and second control valves opens the fifth and sixth flow channels in Region 1, as well as the first and second flow channels in Region 2; fully opening the fifth control valve 7 opens all flow channels in Region 5. At this time, the tuning gas enters the corresponding position in the etching chamber from the aforementioned flow channels. Further, as... Figure 7 As shown, all control valves 7 can also be fully opened, at which point the tuning gas enters the corresponding position of the etching chamber from all the guide channels of the intake ring 6.
[0065] Optionally, the outlet side of the guide member 8 adopts a gradually expanding structure. For example, the outlet side of the guide member 8 adopts a trumpet-shaped structure, which allows the gas to diffuse evenly to the corresponding position in the etching cavity; it also reduces the space occupied by the gas inlet and control valve 7, allowing for precise control of the valve movement of the control valve 7. Further, the guide member 8 has an overall fan-shaped structure. In this embodiment, the guide member 8 can be a distributed design or a one-piece design. If it is a distributed design, each area corresponds to one guide member 8, and multiple guide members 8 are combined to form a complete guide member 8; for example, the guide members 8 are snap-fit connected to each other, thereby achieving quick disassembly. If it is a one-piece design, the size of the guide member 8 can be configured according to the size of the air inlet ring 6.
[0066] Optionally, the interior of the guide member 8 can also be configured as an adjustable angle guide plate, which can be used to adjust the gas injection direction by changing the angle of the guide plate and guide the tuned gas to enter the corresponding position of the etching cavity along a specific path.
[0067] Optionally, spiral grooves or honeycomb structures may be provided on the inner wall of the aforementioned guide plate or guide channel to precisely guide the gas flow to a designated position within the etching cavity.
[0068] The aforementioned gas supply device also includes a guide member 8 connected to the control valve 7. The tuned gas, guided by the guide member 8, can be precisely introduced into the corresponding position of the etching chamber. Furthermore, the outlet side of the guide member 8 adopts a gradually expanding structure. This allows the gas to diffuse evenly to the corresponding position of the etching chamber, while also reducing the space occupied by the gas inlet and the control valve 7, thus enabling precise control of the valve movement of the control valve 7.
[0069] Furthermore, the internal structure of the flow guide 8 can be configured in various ways, such as multiple independent flow channels or an adjustable-angle flow guide plate. Additionally, spiral grooves or honeycomb structures can be formed on the inner walls of the flow guide plate or flow channels. Using these methods, gas flow can be precisely guided to a designated location within the etching cavity, thus mitigating to some extent the asymmetry issues caused by the LT / DEP process used in the front layer and the problem of uneven film thickness in the front layer of the wafer.
[0070] Optionally, in one embodiment, an etching apparatus is also provided, including: an etching chamber, an electrostatic chuck 3, and an air supply device.
[0071] An electrostatic chuck 3 is set inside the etching cavity to fix the wafer 2 to be processed;
[0072] The gas supply device disclosed in the above embodiments includes an inlet ring 6, a gas supply system, and a control valve 7. The gas supply device portion is located on top of the electrostatic chuck 3, meaning the inlet ring 6 and control valve 7 are positioned on top of the electrostatic chuck 3, and are used to output tuning gas to the edge region of the wafer 2 to be processed. It should be noted that the specific structures of each component of the gas supply device have been disclosed in the above embodiments, and will not be repeated here for brevity.
[0073] The aforementioned etching machine has an air inlet ring 6 in the gas supply device, which is configured with multiple zones. Each zone has multiple air channels, and each zone is equipped with a control valve 7. The opening size of the control valve 7 is adjustable. This allows for the selection of opening all or part of the air channels for each zone, thereby precisely controlling the position of the tuning gas entering the etching chamber. This solves to some extent the asymmetry problem caused by the use of LT / DEP process in the front layer and the problem of uneven film thickness in the front layer of the wafer.
[0074] Please note that the above embodiments are for illustrative purposes only and do not imply any limitation on this application.
[0075] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.
[0076] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0077] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A gas supply device, characterized in that, It is applied to an etching machine, the etching machine including an etching chamber, in which a wafer to be processed is placed; the gas supply device includes: an air inlet ring, a gas supply system and a control valve; The intake ring is connected to the air supply system; The intake ring is provided with multiple regions along the circumference; each region is provided with multiple air passages along the circumference. Each of the areas is provided with a control valve, which is used to control the opening or closing of each air passage in the area.
2. The gas supply device according to claim 1, characterized in that, Each of the aforementioned regions is provided with a flow guide, and the flow guide contains the air passage.
3. The gas supply device according to claim 2, characterized in that: Each of the aforementioned regions is evenly distributed on the intake ring, and each of the aforementioned air passages is evenly distributed within the aforementioned regions.
4. The gas supply device according to claim 2, characterized in that: The air outlet side of the guide element adopts a gradually expanding structure.
5. The gas supply device according to claim 2, characterized in that: Each area of the intake ring is provided with an arc-shaped opening.
6. The gas supply device according to claim 1, characterized in that: An air intake pipe is provided on the air intake ring, and the air supply system supplies air to each of the air passages through the air intake pipe.
7. The gas supply device according to claim 6, characterized in that: The gas supply system includes a first gas supply pipe and a second gas supply pipe; the first gas supply pipe and the second gas supply pipe are respectively connected to the air inlet pipe; a first switching valve is provided on the first gas supply pipe, and a second switching valve is provided on the second gas supply pipe, and the control signals of the first switching valve and the second switching valve are opposite.
8. The gas supply device according to claim 2, characterized in that: The air intake ring is located at the top of the etching cavity.
9. The gas supply device according to claim 1, characterized in that: The control valve is a flow control valve.
10. An etching machine, characterized in that, include: Etching cavity; An electrostatic chuck is disposed within the etching cavity to fix the wafer to be processed; The gas supply device according to any one of claims 1-9 is partially disposed on the top of the electrostatic chuck for outputting tuning gas to the edge region of the wafer to be processed.