Ion implanter target stage height calibration tool and calibration method
By combining the EPM optical path calibration fixture and the Faraday centering fixture, the theoretical center position was marked, which solved the problem of target stage assembly error between ion implanters of the same type and achieved the consistency and accurate calibration of the target stage height.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Filing Date
- 2026-02-05
- Publication Date
- 2026-06-19
AI Technical Summary
In the prior art, the target stage assembly error between ion implanters of the same type leads to the difference in the encoding of the center position of the optical path height, which affects the calculation of the overscan range and lacks a consistent calibration method.
Design a calibration fixture that includes an EPM optical path verification fixture and a Faraday centering fixture. By cooperating with the optical path verification rod and the Faraday centering fixture, the theoretical center position is marked. Combined with the grating ruler encoding data, the center position of the target stage height is calculated, assembly errors are eliminated, and consistency is ensured.
It improves the accuracy and consistency of target height calibration, simplifies operation, eliminates assembly errors between different machines, and ensures the consistency of target height.
Smart Images
Figure CN122246030A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of target stage height calibration technology for ion implanters, and specifically to a target stage height calibration fixture and calibration method for ion implanters. Background Technology
[0002] As is well known, ion implanters are one of the key pieces of equipment in semiconductor chip manufacturing. Ion implanters ionize impurity atoms into ions, accelerate them with a high-energy electric field to achieve high speeds, and then implant them into the wafer surface placed on a target stage within a vacuum target chamber. Therefore, the height calibration of the target stage is a crucial step in ensuring that the ion beam is precisely focused on a specific location on the wafer.
[0003] In reality, unavoidable errors exist during target assembly. Currently, optical path calibration only applies to a single machine and does not consider consistency between machines of the same type. However, assembly errors between machines of the same type can lead to differences in the encoding of the target disk at the center position of the optical path height on different machines, thus affecting the calculation of the overscan range. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a compact, easy-to-operate ion implanter target stage height calibration fixture and calibration method that addresses the shortcomings of the prior art and is conducive to improving calibration accuracy.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: An ion implanter target stage height calibration fixture includes an EPM optical path verification fixture and a Faraday alignment fixture. The Faraday alignment fixture is detachably mounted on a movable Faraday component within the ion implanter cavity, and has a notch for marking the theoretical Faraday beam center position. The EPM optical path verification fixture is installed at the optical path entrance of the ion implanter cavity and includes an optical path verification rod for marking the theoretical EPM optical path center. After the EPM optical path verification fixture and the Faraday alignment fixture are installed, if the head of the optical path verification rod coincides with the notch on the Faraday alignment fixture, it indicates that the theoretical EPM optical path center coincides with the center of the movable Faraday optical path.
[0006] As a further improvement of the present invention, the EPM optical path verification fixture includes a detachably connected optical path verification seat and an optical path verification plate. The optical path verification plate is detachably installed at the optical path inlet of the ion implanter cavity, and the optical path verification seat and the optical path verification plate are provided with a through guide hole, and the optical path verification rod passes through the guide hole.
[0007] As a further improvement of the present invention, the tail end of the optical path verification rod is provided with an electrode position detection seat.
[0008] As a further improvement of the present invention, the Faraday centering fixture includes a detachably connected Faraday centering seat and a Faraday centering plate, the Faraday centering plate being detachably mounted on a movable Faraday assembly, and the upper part of the Faraday centering seat having a cutout.
[0009] As a further improvement of the present invention, the lower part of the Faraday centering seat is provided with a first positioning pin.
[0010] As a further improvement of the present invention, the width and depth of the cut are both 0.5±0.02mm.
[0011] As a general technical concept, the present invention also provides a method for calibrating the target stage height of an ion implanter based on the above-mentioned target stage height calibration fixture, comprising the following steps: Step S1: Assemble the Faraday centering fixture; Step S2: Assemble the EPM optical path verification fixture; Step S3: Install the EPM optical path verification fixture at the optical path inlet of the ion implanter cavity; Step S4: Install the Faraday centering fixture on the moving Faraday component; Step S5: Make the optical path verification rod in the EPM optical path verification fixture contact with the cut in the Faraday centering fixture; Step S6: Inside the ion implanter chamber, measure the height h1 from the bottom of the target disk to the upper surface of the target stage, the height h2 from the top of the target disk to the upper surface of the target stage, and the height h3 from the moving Faraday center to the upper surface of the target stage. Based on the above three height data, calculate the height H from the center of the target stage to the center of the optical path. The units of measurement for h1, h2, h3, and H are all mm. Step S7: Inside the ion implanter chamber, read the grating ruler encoding data X at the corresponding position of the target stage; Step S8: Combine the height value H from the target center to the optical path center obtained in step S6 with the grating ruler encoding data X obtained in step S7 to calculate the target height center position value CP. CP = X + H × 1000, which is the grating ruler encoding data at any position on the target stage; Step S9: Write the Y value into the control program of the ion implanter.
[0012] As a further improvement of the present invention, in step S5, the movable Faraday component is dragged to the top of the target stage, and the optical path verification rod is moved so that the head of the optical path verification rod contacts the Faraday centering seat. The contact between the head of the optical path verification rod and the cut on the Faraday centering seat is observed. If the head of the optical path verification rod coincides with the cut, it indicates that the theoretical center of the EPM optical path coincides with the center of the movable Faraday optical path.
[0013] As a further improvement of the present invention, in step S6, the X-tilt and Y-tilt angles of the target stage are adjusted until the target plate is in a vertical state and parallel to the inlet flange on the moving Faraday assembly, and h1, h2 and h3 are measured with a ruler. Based on the formula: H=h3-(h1+h2) / 2, the height H from the center of the target stage to the center of the optical path is calculated when the target stage is in the initial position.
[0014] As a further improvement of the present invention, h1, h2 and h3 are each measured with at least three sets of data and the average value is taken.
[0015] Compared with the prior art, the advantages of the present invention are as follows: The target stage height calibration fixture and calibration method of the ion implanter of the present invention are designed based on the theoretical optical path center. By using the cooperation of Faraday centering fixture and EPM optical path verification fixture, the target stage height center is calibrated, which meets the theoretical requirements of centering and is easy to operate. It eliminates the assembly error between different machines and ensures the consistency of target stage height between different machines. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the target stage height calibration process of the ion implanter in a specific embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the structural principle of the Faraday centering seat in a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the assembly of the Faraday centering tool in a specific embodiment of the present invention; Figure 4 This is a schematic diagram of the assembly of the verification rod and the electrode position detection seat in a specific embodiment of the present invention; Figure 5 This is a schematic diagram of the optical path verification base in a specific embodiment of the present invention; Figure 6 This is a schematic diagram of the assembly of the optical path verification component in a specific embodiment of the present invention; Figure 7 This is a schematic diagram of the assembly of the EPM optical path verification fixture in a specific embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the EPM optical path verification fixture installed on the cavity in a specific embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the Faraday centering tooling installed on the mobile Faraday component in a specific embodiment of the present invention; Figure 10 This is a schematic diagram of the structure in which the optical path verification rod contacts the Faraday centering seat in a specific embodiment of the present invention; Figure 11This is a schematic diagram of the target stage height measurement in a specific embodiment of the present invention; wherein, h0 represents the reference height of the upper surface of the target stage, mm; h1 represents the height from the bottom of the target disk to the upper surface of the target stage, mm; h2 represents the height from the top of the target disk to the upper surface of the target stage, mm; h3 represents the height from the moving Faraday center to the upper surface of the target stage, mm; H represents the height from the center of the target stage to the center of the optical path, mm; Figure 12 This is a schematic diagram illustrating the calibration theory of the target platform height in a specific embodiment of the present invention.
[0017] Legend: 1. Faraday centering seat; 2. Cutout; 3. First locating pin; 4. Mounting hole; 5. Faraday centering plate; 6. Second locating pin; 7. Electrode position detection seat; 8. Optical path verification rod; 9. Optical path verification seat; 10. Third locating pin; 11. Optical path verification plate; 12. Fastening screw; 100. Ion implanter chamber; 101. Target stage; 102. Target plate; 200. EPM optical path verification fixture; 300. Faraday centering fixture; 400. Moving Faraday assembly; 401. Entrance aperture. Detailed Implementation
[0018] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.
[0019] In the description of this invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as a limitation of this invention.
[0020] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more unless otherwise explicitly specified.
[0021] Example like Figures 2 to 10As shown, the ion implanter target stage height calibration fixture of the present invention includes an EPM optical path verification fixture 200 and a Faraday alignment fixture 300. The Faraday alignment fixture 300 is detachably mounted on a movable Faraday component 400 within the ion implanter cavity 100, and has a notch 2 for marking the theoretical Faraday beam center position. The EPM optical path verification fixture 200 is installed at the optical path entrance of the ion implanter cavity 100, and includes an optical path verification rod 8 for marking the theoretical EPM optical path center. After the EPM optical path verification fixture 200 and the Faraday alignment fixture 300 are installed, if the head of the optical path verification rod 8 coincides with the notch 2 on the Faraday alignment fixture 300, it indicates that the theoretical EPM optical path center coincides with the center of the movable Faraday optical path.
[0022] In this embodiment, the design is based on the theoretical optical path center. The Faraday centering fixture 300 and the EPM optical path verification fixture 200 are used to calibrate the target height center, which meets the theoretical requirements of centering and is easy to operate. This eliminates the assembly errors between different machines and ensures the consistency of the target height between different machines.
[0023] like Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, the EPM optical path verification fixture 200 includes a detachably connected optical path verification base 9 and an optical path verification board 11. For example... Figure 8 As shown, the optical path verification plate 11 is detachably installed at the optical path entrance of the ion implanter cavity 100 by fastening screws 12, and the optical path verification seat 9 and the optical path verification plate 11 are provided with through guide holes, and the optical path verification rod 8 passes through the guide holes.
[0024] Furthermore, the tail of the optical path calibration rod 8 is provided with an electrode position detection seat 7 to detect whether the focusing electrode of the EPM can be located in the detection seat slot. If it can, it means that the center of the EPM optical path is correct.
[0025] like Figure 2 and Figure 3 As shown, the Faraday centering fixture 300 includes a detachably connected Faraday centering seat 1 and a Faraday centering plate 5, as... Figure 9 As shown, the Faraday centering plate 5 is detachably mounted on the entrance light barrier 401 of the movable Faraday assembly 400 via the second positioning pin 6, and a cutout 2 is provided on the upper part of the Faraday centering seat 1.
[0026] Furthermore, the width and depth of notch 2 are both approximately 0.5 mm. By marking the center of the moving Faraday optical path through notch 2, the calibration error can be controlled within ±0.5 mm, significantly improving the accuracy of target stage height calibration.
[0027] like Figure 2 As shown, the Faraday centering seat 1 has mounting holes 4, into which fasteners are screwed to achieve a detachable connection between the Faraday centering seat 1 and the Faraday centering plate 5. The lower part of the Faraday centering seat 1 has a first positioning pin 3, on which a lifting ring can be installed to check the verticality of the Faraday centering seat 1.
[0028] like Figure 1 and Figure 12 As shown, this embodiment also provides a method for calibrating the target stage height of an ion implanter based on the above-mentioned calibration fixture, including the following steps: Step S1: Assemble the Faraday centering fixture 300. Assemble the Faraday centering plate 5 and the Faraday centering seat 1 together using screws, as follows: Figure 3 As shown.
[0029] Step S2: Assemble the EPM optical path verification fixture 200. First, assemble the optical path verification rod 8 and the electrode position detection seat 7 together using screws, as follows: Figure 4 As shown; secondly, install the third positioning pin 10 onto the optical path verification seat 9, as follows. Figure 5 As shown; then, use screws and flat washers to install the optical path verification seat 9, which has the third positioning pin 10 installed, onto the optical path verification plate 11, as shown. Figure 6 As shown; finally, insert the optical path verification rod 8 into the guide holes of the optical path verification seat 9 and the optical path verification plate 11 to form the EPM optical path verification fixture 200, as shown. Figure 7 As shown.
[0030] Step S3: Install the EPM optical path verification fixture 200 at the optical path entrance of the ion implanter cavity 100, such as... Figure 8 As shown.
[0031] Step S4: Install the Faraday centering fixture 300 on the opening of the inlet aperture 401 of the movable Faraday component 400, such as... Figure 9 As shown.
[0032] Step S5: Make contact between the optical path verification rod 8 in the EPM optical path verification fixture 200 and the cutout 2 in the Faraday centering fixture 300. Specifically, as follows... Figure 10 As shown, drag the movable Faraday component 400 above the target stage 101, move the optical path verification rod 8 so that the head of the optical path verification rod 8 contacts the Faraday centering seat 1, and observe the contact between the head of the optical path verification rod 8 and the cut 2 on the Faraday centering seat 1; if the head of the optical path verification rod 8 coincides with the cut 2, it indicates that the theoretical center of the EPM optical path coincides with the center of the movable Faraday optical path.
[0033] Step S6: Within the ion implanter cavity 100, measure the height h1 from the bottom of the target disk 102 to the upper surface of the target stage 101, the height h2 from the top of the target disk 102 to the upper surface of the target stage 101, and the height h3 from the moving Faraday center to the upper surface of the target stage 101. Based on these three height data, calculate the height H from the center of the target stage 101 to the center of the optical path. Figure 11 As shown; where h1, h2, h3 and H are all measured in mm.
[0034] Specifically, adjust the X-tilt and Y-tilt angles of the target stage 101 until the target plate 102 is in a vertical position and parallel to the inlet flange on the moving Faraday assembly 400. Use a ruler to measure h1, h2 and h3; and measure at least three sets of data for each of h1, h2 and h3, and take the average value to improve the accuracy of the measurement.
[0035] Based on the formula: H=h3-(h1+h2) / 2, the height H from the center of the target stage 101 to the center of the optical path is calculated when the target stage 101 is in the initial position.
[0036] Step S7: Inside the ion implanter cavity 100, read the encoded data X of the mechanical scanning grating ruler at the corresponding position of the target stage 101.
[0037] Step S8: Combining the height value H from the center of the target stage 101 to the center of the optical path obtained in step S6 and the grating ruler encoding data X obtained in step S7, calculate the height center position value CP of the target stage 101 according to the calculation formula of the height center position of the target stage 101. CP = X + H × 1000, the grating ruler encoding data at any position of the target stage 101; where, the conversion relationship between encoding and distance is determined according to the specifications of the grating ruler: 1000cont = 1mm.
[0038] Step S9: Write the Y value into the control program of the ion implanter, thus completing the target stage height calibration.
[0039] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.
Claims
1. A target stage height calibration fixture for an ion implanter, characterized in that, The assembly includes an EPM optical path verification fixture (200) and a Faraday centering fixture (300); the Faraday centering fixture (300) is detachably mounted on a movable Faraday assembly (400) inside the ion implanter cavity (100), and the Faraday centering fixture (300) has a notch (2) for marking the position of the Faraday theoretical beam center; the EPM optical path verification fixture (200) is mounted on the ion implanter cavity (100). At the optical path entrance of 0), the EPM optical path verification fixture (200) includes an optical path verification rod (8), which is used to mark the theoretical center of the EPM optical path. After the EPM optical path verification fixture (200) and the Faraday alignment fixture (300) are installed, if the head of the optical path verification rod (8) coincides with the cut (2) on the Faraday alignment fixture (300), it indicates that the theoretical center of the EPM optical path coincides with the center of the moving Faraday optical path.
2. The target stage height calibration fixture for an ion implanter according to claim 1, characterized in that, The EPM optical path verification fixture (200) includes a detachably connected optical path verification seat (9) and an optical path verification plate (11). The optical path verification plate (11) is detachably installed at the optical path entrance of the ion implanter cavity (100). The optical path verification seat (9) and the optical path verification plate (11) are provided with through guide holes, and the optical path verification rod (8) passes through the guide holes.
3. The target stage height calibration fixture for an ion implanter according to claim 2, characterized in that, The tail of the optical path verification rod (8) is provided with an electrode position detection seat (7).
4. The target stage height calibration fixture for an ion implanter according to claim 1, characterized in that, The Faraday centering fixture (300) includes a detachably connected Faraday centering seat (1) and a Faraday centering plate (5). The Faraday centering plate (5) is detachably mounted on a movable Faraday assembly (400). The upper part of the Faraday centering seat (1) is provided with a cutout (2).
5. The target stage height calibration fixture for an ion implanter according to claim 4, characterized in that, The Faraday centering seat (1) is provided with a first positioning pin (3) at its lower part.
6. The target stage height calibration fixture for an ion implanter according to claim 4, characterized in that, The width and depth of the cut (2) are both 0.5±0.02mm.
7. A method for calibrating the height of an ion implanter target stage based on the ion implanter target stage height calibration fixture according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step S1: Assemble the Faraday centering fixture (300). Step S2: Assemble the EPM optical path verification fixture (200). Step S3: Install the EPM optical path verification fixture (200) at the optical path entrance of the ion implanter cavity (100); Step S4: Install the Faraday centering fixture (300) on the movable Faraday component (400); Step S5: Make the optical path verification rod (8) in the EPM optical path verification fixture (200) contact the cut (2) in the Faraday centering fixture (300); Step S6: Inside the ion implanter cavity (100), measure the height h1 from the bottom of the target disk (102) to the upper surface of the target stage (101), the height h2 from the top of the target disk (102) to the upper surface of the target stage (101), and the height h3 from the moving Faraday center to the upper surface of the target stage (101). Based on the above three height data, calculate the height H from the center of the target stage (101) to the center of the optical path. The units of measurement for h1, h2, h3 and H are all mm. Step S7: Inside the ion implanter cavity (100), read the grating ruler encoding data X at the corresponding position of the target stage (101); Step S8: Combine the height value H from the center of the target platform (101) to the center of the optical path obtained in step S6 with the grating ruler encoding data X obtained in step S7, and calculate the height center position value CP of the target platform (101). CP = X + H × 1000, which is the grating ruler encoding data at any position of the target stage (101); Step S9: Write the Y value into the control program of the ion implanter.
8. The method for calibrating the target stage height of an ion implanter according to claim 7, characterized in that, In step S5, the movable Faraday component (400) is dragged above the target stage (101), and the optical path verification rod (8) is moved so that the head of the optical path verification rod (8) contacts the Faraday centering seat (1). The contact between the head of the optical path verification rod (8) and the cut (2) on the Faraday centering seat (1) is observed. If the head of the optical path verification rod (8) coincides with the cut (2), it indicates that the theoretical center of the EPM optical path coincides with the center of the movable Faraday optical path.
9. The method for calibrating the target stage height of an ion implanter according to claim 7, characterized in that, In step S6, the X-tilt and Y-tilt angles of the target stage (101) are adjusted until the target plate (102) is in a vertical state and parallel to the inlet flange on the moving Faraday assembly (400), and h1, h2 and h3 are measured with a ruler. Based on the formula: H=h3-(h1+h2) / 2, the height H of the target stage (101) from the center of the optical path to the center of the target stage (101) when it is in the initial position is calculated.
10. The method for calibrating the target stage height of an ion implanter according to claim 9, characterized in that, Each of h1, h2, and h3 requires at least three sets of data, and the average value is taken.