System and method for optimizing the fully horizontal scanned beam distance

Abstract

A method for optimizing the fully horizontal scanned beam distance of an accelerator beam is provided herein. In one method, the method includes placing a first Faraday cup along a first side of an intended beam scan region, placing a second Faraday cup along a second side of the intended beam scan region, scanning an ion beam along the first and second sides of the intended beam scan region, measuring a first beam current of the ion beam at the first Faraday cup and measuring a second beam current of the ion beam at the second Faraday cup, and determining an optimal scan distance of the ion beam across the intended beam scan region based on the first beam current and the second beam current.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of priority of U.S. Patent Application No. 17 / 827,204, filed May 27, 2022, which is hereby incorporated by reference in its entirety.

[0002] The present disclosure generally relates to ion beam processing techniques, and more particularly to systems and methods for optimizing the fully horizontal scanned beam distance.

Background Art

[0003] Today, various types of processing apparatuses are employed to treat or process substrates with ions. In a processing substrate such as a semiconductor substrate, ions can be used to etch layers or features on the substrate. Ions can also be used to deposit a layer or structure on the substrate, to implant nuclides into the substrate, or to amorphize the substrate. Also, techniques have been developed for monitoring the processing of the substrate in order to control the processing of the substrate.

[0004] To scan a beam across the wafer diameter, a horizontal scan distance is used. Current techniques use an estimation of the beam edge to estimate the total required horizontal scan distance. However, due to the fact that no actual measurement is carried out to confirm that the beam is sufficiently scanned across the wafer, over - scanning or under - scanning of the wafer often occurs.

[0005] Therefore, it would be beneficial to ensure that the beam is sufficiently scanned across the entire wafer diameter in order to provide uniform implantation and to optimize the beam current utilized during the implantation of the wafer. In view of this and other considerations, the present disclosure is provided.

Summary of the Invention

[0006] The summary of the present invention is provided in a simplified manner to introduce the selection of concepts further described below in modes for carrying out the invention. The summary of the present invention does not identify the main or essential features of the claimed subject matter, nor does it help in determining the scope of the claimed subject matter.

[0007] In one embodiment, the method may include providing a first Faraday cup position along a first side of an intended beam-scan area; providing a second Faraday cup position along a second side of the intended beam-scan area; scanning an ion beam along the first and second sides of the intended beam-scan area; measuring a first beam current of the ion beam at the first Faraday cup position; measuring a second beam current of the ion beam at the second Faraday cup position; and determining an optimal scan distance of the ion beam across the intended beam-scan area based on the first and second beam currents.

[0008] In another embodiment, a device for optimizing the scanned beam distance of an ion beam may include a beam scanner operable to scan a spot ion beam with respect to an intended beam scan region, a Faraday cup positioned along a first side of the intended beam scan region, and a Faraday profiler positioned along a second side of the intended beam scan region, wherein the Faraday cup is operable to measure a first beam current of the spot ion beam, and the Faraday profiler is operable to measure a second beam current of the spot ion beam. The device may further include a beam calibration component comprising a controller and memory, wherein the memory comprises a calibration routine operable on the controller to determine an optimal scan distance of the ion beam based on a first beam current and a second beam current.

[0009] In another embodiment, a non-temporary computer-readable storage medium includes instructions, which, when executed by a computer, cause the computer to scan a spot ion beam with a beam scanner with respect to an intended beam scan area, measure a first beam current of the spot ion beam in a first Faraday cup positioned along a first side of the intended beam scan area, and measure a second beam current of the spot ion beam in a second Faraday cup positioned along a second side of the intended beam scan area. The non-temporary computer-readable storage medium further includes instructions, when executed by a computer, causing the computer to determine an optimal scan distance of the ion beam based on the first and second beam currents.

[0010] Next, an embodiment of the present disclosure will be described as an example, with reference to the accompanying drawings. [Brief explanation of the drawing]

[0011] [Figure 1] This is a diagram of a system according to an embodiment of the present disclosure, including a pair of Faraday cup positions for determining the beam distance to be scanned. [Figure 2] A and B are graphs showing current-multiplicative values ​​according to embodiments of the present disclosure. [Figure 3] This is a diagram of a system according to an embodiment of the present disclosure, including a pair of Faraday cup positions for determining the beam distance to be scanned. [Figure 4A] This is a diagram of a system according to an embodiment of the present disclosure, including a pair of Faraday cup positions for determining the beam distance to be scanned. [Figure 4B] This is a graph showing current-to-position pairs according to an embodiment of the present disclosure. [Figure 4C] This is a graph showing current-to-position pairs according to an embodiment of the present disclosure. [Figure 5]This is a block plan view of a beamline ion implantation apparatus according to various embodiments of the present disclosure. [Figure 6] This is an exemplary process flow of the method according to various embodiments of the present disclosure. [Modes for carrying out the invention]

[0012] The drawings are not necessarily to a fixed scale. The drawings are for illustrative purposes only and do not depict any specific parameters of the disclosure. The drawings illustrate exemplary embodiments of the disclosure and should therefore not be considered limiting. In the drawings, similar numbering represents similar elements.

[0013] Furthermore, some elements in some of the figures may be omitted or not shown at a certain scale in order to clarify the explanation. Sectional views may be in the form of "fragmentary" or "myopic" sections, omitting some background lines that would normally be visible in an "accurate" section, in order to clarify the explanation. In addition, for clarity, some reference numbers may be omitted in some drawings.

[0014] Next, these embodiments will be described more thoroughly below with reference to the accompanying drawings, which show several embodiments. The subject matter of this disclosure can be embodied in many different forms and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure is thorough and complete and so well conveys the scope of the subject matter to those skilled in the art. Similar numbers refer to similar elements throughout.

[0015] Embodiments described herein provide a novel technique for optimizing the horizontal scan distance of an accelerator beam using beam current measurements from a set of Faraday cups positioned at opposing edges of a wafer. Unlike prior art methods, which use beam edge estimation in an attempt to determine the total required horizontal scan distance, embodiments of the disclosure use actual beam current measurements from Faraday cups positioned on each side of the wafer to determine the optimal beam distance to scan. This ensures that the beam passes beyond the wafer edges, minimizing additional overscanned distance. Advantageously, there is no wasted beam current when the beam leaves the wafer, and the beam current is utilized / optimized during wafer injection. Furthermore, embodiments of the specification ensure that the beam is sufficiently scanned across the entire wafer diameter to ensure uniform injection. Also advantageously, embodiments of the specification ensure accurate measurements from the injection monitoring Faraday cups for dose accuracy.

[0016] Figure 1 shows a first embodiment of a device 100 for determining the optimal scan distance for an ion implanter. The device 100 may include a Faraday cup 101 at a first Faraday cup position 102 along a first side 104 of the intended beam scan region 106, and a Faraday cup or Faraday profiler 103 at a second Faraday cup position 110 along a second side 112 of the intended beam scan region 106. In some embodiments, only a Faraday cup 101 is present, and measurements are taken at multiple positions by a single Faraday cup 101.

[0017] While not limiting, the Faraday cup 101 is generally fixed along the x-direction, but the Faraday profiler 103 may move horizontally along the x-direction. For example, the Faraday profiler 103 may be positioned inside or outside the intended beam scanning area 106. The first Faraday cup 102 may include a first opening (not shown) that is operable to receive an indication of the current of the ion beam 114 when the ion beam 114 is scanned horizontally near the first side 104 (for example, along the x-direction in the illustrated orientation). The Faraday profiler 103 may measure the current of the ion beam 114 when the ion beam 114 is scanned horizontally near the second side 112. As further described herein, measurements obtained from the Faraday cup 101 and the Faraday profiler 103 can be used to determine when the beam current completely passes through specific locations outside the intended beam scan region 106, such as the first opening in the Faraday cup 101. The ion beam 114 may, but not limited to, be an accelerator spot beam. In some cases, the left and right edges of the ion beam 114 may be detected as it passes near the Faraday cup 101 and the Faraday profiler 103. These edges may represent approximately 0.6% of the detected peak (not the integrated current) of the spot ion beam 114.

[0018] The intended beam scan region 106 may generally correspond to the region where the wafer is to be processed (e.g., scanned) by the ion beam 114. During use, the ion beam 114 may be scanned horizontally (e.g., in the x direction), while the wafer may be moved vertically (e.g., along the y direction). The implantation region 106 may be defined by the outer perimeter 124, and the first side 104 and the second side 112 may correspond to opposing points on the circumference along the outer perimeter 124. The diameter of the intended beam scan region 106 may extend between the first side 104 and the second side 112. In the illustrated embodiment, the Faraday cup 101 is disposed outside the outer perimeter 124 in the first overscan region 130, and the Faraday profiler 103 is disposed outside the outer perimeter 124 in the second overscan region 132. The first overscan region 130 may include a first CLF dimension (CD1) corresponding to the length (e.g., along the x direction) between the first aperture and the first side 104.

[0019] During use, the ion beam 114 is scanned between the first side 104 and the second side 110 of the intended beam scan region 106. The first beam current of the ion beam 114 is measured at the first Faraday cup position 102, and the second beam current of the ion beam 114 is measured at the second Faraday cup position 110. Based on the first beam current and the second beam current, the optimal scan distance of the ion beam across the intended beam scan region 106 and across the first overscan region 130 and the second overscan region 132 may be determined. Advantageously, by optimizing the horizontal scan distance, the beam current may be increased. More specifically, embodiments herein reduce the horizontal scan distance as much as possible to maximize the beam current in the case of a high-dose strategy. In another example, the horizontal scan distance is increased in the case of a low-dose strategy, and thus the beam current may be reduced. In other words, the apparatus 100 enables rapid adjustment of that distance to hold the beam current down to the target such that the horizontal scan distance is at least the minimum HSD.

[0020] In one embodiment, the ion beam 114 is scanned over a wide horizontal distance (e.g., from the first overscan region 130 to the second overscan region 132), and then the width in the horizontal direction can be gradually reduced toward the center of the intended beam scan region 106. FIG. 2A shows the relationship between the current and the first Faraday cup multiplier (hereinafter multiplier 1). As shown by the reference line 133, the current is expected to increase linearly as the overscan is reduced. In other words, as the ion beam 114 moves away from the first overscan region 130 and toward the intended beam scan region 106, the current increases. A line 135 tracking an exemplary current measurement by the Faraday cup 101 shows a case where the overscan is insufficient and the line 135 deviates from the reference line 133. To determine an appropriate value for multiplier 1, a current deviation above or below a first predetermined threshold can be used. For example, a scan location before a "x"% drop in current from the expected value (reference line 133) can be selected. In various examples, "x" can be between 0.01 and 10. Thus, multiplier 1 can be approximately 1.1, as shown by line 138 in this example.

[0021] As shown in FIG. 2B, a similar analysis can be performed for the Faraday profiler 103. The reference line 133 corresponds to the expected current that increases linearly, and the line 139 connects an exemplary current measurement by the Faraday profiler 103. To determine an appropriate value for the second Faraday cup multiplier (hereinafter multiplier 2), a current deviation above or below a second predetermined threshold, in this case, a scan location before a "x"% drop in current from the expected value (reference line 133) can be used. In various examples, "x" can be between 0.01 and 10. Thus, multiplier 2 can be approximately 0.8, as shown by line 140 in this example.

[0022] The dynamic horizontal scan distance (ScanWidthTotal) of the ion beam 114 can be determined with respect to the intended beam scan region 106 of the instrument 100, the first overscan region 130, and the second overscan region 132 using the following equation (1). ScanWidthTotal=Multipler1*Beam width +CLF distance +Wafer Diameter +Multipler2*Beam width (1)

[0023] In the above, Beam width This is a measurable value and may vary depending on the parameters of the ion beam 114.

[0024] Figure 3 shows another method for determining the horizontal scan distance for apparatus 200. Apparatus 200 may be the same as or similar to apparatus 100. Therefore, only a few embodiments of apparatus 200 are described below for brevity. In this embodiment, a set of stationary spot ion beams 214A and 214B are initially positioned in a first overscan region 230 and a second overscan region 232, respectively. The first ion beam 214A can be iteratively shifted towards a Faraday cup 201 at a first Faraday position 202 via a scanner commanded to a fixed position. The Faraday cup 201 measures the increase in current as the first ion beam 214A moves towards the intended beam scan region 206. Similarly, the second ion beam 214B can be iteratively shifted towards a Faraday profiler 203 at a second Faraday position 210 via a scanner commanded to a fixed position. The Faraday profiler 203 measures the increase in current as the second ion beam 214B moves toward the intended beam scan region 206. The scan distance can be set based on the point where each beam is outside the intended beam scan region 206 and the Faraday cup 201 and Faraday profiler 203 do not measure the increased beam current from no-beam offset. Equation (1) above can be used again to calculate the horizontal scan distance.

[0025] Figures 4A–4C illustrate yet another method for determining the dynamic horizontal scan distance of a “fast spot” beam. In the “fast spot” beam method, the spot beam 214A may be swept multiple times, such as 16 times, across the Faraday cup 201 to obtain the average current response as a fast spot profile, which may require approximately 3 seconds. Similarly, the spot beam 214B may be swept multiple times, such as 16 times, across the Faraday profiler 203 to obtain the average current response as a fast spot profile. In this embodiment, the fast spot ion beam may be scanned around the CLF position (i.e., opening) of the Faraday cup 201 to determine the current-to-position profile 260, as shown in Figure 4B. The fast spot ion beam may similarly be scanned in the Faraday profiler 203 to determine the current edge at the edge of the intended beam scan region 206, based on the current-to-position profile 262 shown in Figure 4C. High-speed spot data can then be used to determine the edge of the measured current, and the scan distance can then be set based on the high-speed spot current measurement distance.

[0026] Figure 5 shows a block-form plan view of a beamline ion implanter, shown as ion implanter 300, according to various embodiments of the present disclosure. The ion implanter 300 includes an ion source 302 configured to produce an ion beam 304. The ion beam 304 may be provided as a spot beam scanned along a direction such as the X direction. By convention as used herein, the Z direction refers to the direction of an axis parallel to the central ray trajectory of the ion beam 304. Thus, the absolute direction of the Z direction and the absolute direction of the X direction, where the X direction is perpendicular to the Z direction, may vary at different points within the ion implanter 300, as shown. The ion beam 304 may travel through an analyzer magnet 306, a mass separation slit 308, and a collimator 312 before affecting a substrate 316 disposed on a substrate stage 314. In some embodiments, the substrate stage 314 may be configured to scan the substrate 316 along at least the Y direction. In the example shown in Figure 5, the ion implanter 300 includes a beam scanner 310. When the ion beam 304 is provided as a spot beam, the beam scanner 310 scans the ion beam 304 along the X direction, producing a scanned ion beam, which can also be scanned on the substrate along the X direction. The width of the resulting scanned spot beam may correspond to the width W of the substrate 316.

[0027] The ion implanter 300 further includes a set of current detectors 318A–318B, including a Faraday cup current detector and, in particular, a closed-loop Faraday current detector for monitoring the beam current supplied to the substrate 316, as well as a profiler Faraday cup for measuring beam uniformity. The current detectors 318A–318B may be positioned along opposing sides of the substrate 316 to intercept the ion beam 304 and may be configured to record the beam current of the ion beam 304 during various horizontal scanning beam distance optimization operations as described above.

[0028] The ion implanter 300 also includes a beam calibration component 320. The beam calibration component 320 may be coupled to the beam scanner 310 and current detectors 318A and 318B. The beam calibration component 320 may be coupled to one or more components to adjust the scan of the ion beam 304 in order to provide more uniform and efficient ion implantation to the substrate 316 as a result of a beam distance optimization procedure. The beam calibration component 320 may include logic for determining ScanWidthTotal based on the application of various beam measurements and for determining the application of routines based on these measurements, as described in the example above. The logic may further generate adjustment signals for adjusting the scan of the ion beam 304 based on the determined ScanWidthTotal. In some cases, the logic of the beam calibration component 320 may be implemented in combination of software and hardware or firmware. In some examples, the beam calibration component 320 may include a circuit such as a controller 320-A and a software-coupled memory 320-B for executing instructions to adjust the scan of the ion beam 304 based on the determination of ScanWidthTotal. Embodiments are not limited to this context.

[0029] Referring to Figure 6, a method 400 according to an embodiment of the present disclosure is described. In block 401, the method 400 may include providing a first Faraday cup position along a first side of the intended beam scan region and providing a second Faraday cup position along a second side of the intended beam scan region. In some embodiments, the Faraday cup may be located at the first Faraday cup position, and the Faraday profiler may be located at the second Faraday cup position. The first and second Faraday cup positions may be located along the same horizontal axis at points opposite each other in the circumferential direction of the intended beam scan region.

[0030] In block 402, method 400 may further include scanning the ion beam along a first and a second side of the intended beam scan region. In some embodiments, the ion beam may be scanned completely across the intended beam scan region and between a first Faraday cup position and a second Faraday cup position. In some embodiments, the ion beam may be scanned only at the first and second Faraday cup positions. That is, a spot beam may be held beyond each of the Faraday cups and Faraday profilers, moved inward toward the intended beam scan region, and stopped at the edge of the intended beam scan region. This process may be carried out using high-speed spot beam operation.

[0031] In block 403, method 400 may include measuring a first beam current of the ion beam at a first Faraday cup position and measuring a second beam current of the ion beam at a second Faraday cup position.

[0032] In block 404, method 400 may include determining an optimal scan distance of the ion beam over an intended beam scan region based on a first beam current and a second beam current. In some embodiments, determining the optimal scan distance includes scanning the ion beam over a first side of the intended beam scan region until the ion beam has completely passed through a first opening in the Faraday cup, and scanning the ion beam over a second side of the intended beam scan region until the ion beam has completely passed through the Faraday profiler. In some embodiments, the method may further include determining that the ion beam has completely passed through the first opening in the Faraday cup when a first current measurement in the Faraday cup reaches a first predetermined threshold, and determining that the ion beam has completely passed through a second opening in the second Faraday cup when a second current measurement in the second Faraday cup reaches a second predetermined threshold.

[0033] The above description is presented for illustrative and explanatory purposes only and does not limit the disclosure to one or more forms disclosed herein. For example, various features of the disclosure may be grouped together in one or more aspects, embodiments, or configurations for the purpose of streamlining the disclosure. However, it should be understood that various features of some aspects, embodiments, or configurations of the disclosure may be combined in alternative aspects, embodiments, or configurations. Furthermore, the following claims are incorporated herein into the forms for carrying out the invention by this reference, and each claim stands independently as an individual embodiment of the disclosure.

[0034] Any element or step described herein in the singular and beginning with the word "a" or "an" should be understood not to exclude multiple elements or steps unless such exclusion is expressly stated. Furthermore, any reference to “one embodiment” in this disclosure should not be construed as excluding the existence of additional embodiments that also incorporate the described features.

[0035] The use of “including,” “comprising,” or “having” and their variations herein encompasses the items and their equivalents listed thereafter, as well as any additional items. Therefore, the terms “including,” “comprising,” or “having” and their variations are open-ended and may be used interchangeably herein.

[0036] References indicating all directions (e.g., proximal, distal, upper, lower, upward, downward, left, right, transverse, vertical, front, back, top, bottom, up, down, vertical, horizontal, radial, axial, clockwise, and counterclockwise) are used solely for identification purposes to aid the reader's understanding of this disclosure and do not create any limitation in terms of location, orientation, or use of this disclosure. References of connections (e.g., attached, joined, connected, and joined) should be interpreted broadly and, unless otherwise specified, may include intermediate members between sets of elements and relative movement between elements. Thus, references to connections do not necessarily imply that two elements are directly connected and fixed to one another.

[0037] Furthermore, identifying references (e.g., primary, secondary, first, second, third, fourth, etc.) are not intended to imply importance or priority, but are used to distinguish one feature from another. The drawings are for illustrative purposes only, and the dimensions, locations, order, and relative sizes reflected in the drawings attached herein may vary.

[0038] Furthermore, the terms “substantial” or “substantially,” as well as “approximate” or “approximately,” may be used interchangeably in some embodiments and may be described using any relative measure acceptable to those skilled in the art. For example, these terms may serve as a comparison with a reference parameter to indicate a deviation that can provide the intended function. While not limiting, the deviation from the reference parameter may be in quantities such as less than 1%, less than 3%, less than 5%, less than 10%, less than 15%, or less than 20%.

[0039] While several embodiments of the present disclosure have been described herein, the present disclosure is broad in scope to the extent permitted by the art, and this specification can be read similarly; therefore, the present disclosure is not limited to those embodiments. Accordingly, the above description should not be construed as limiting. Those skilled in the art will anticipate other modifications within the scope and spirit of the claims appended herein.

Claims

1. A method, To provide a first Faraday cup position along the first side of the intended beam scan region, To provide a second Faraday cup position along the second side of the intended beam scan region, Scanning the ion beam along the first and second sides of the intended beam scan region, The first beam current of the ion beam at the first Faraday cup position is measured, and the second beam current of the ion beam at the second Faraday cup position is measured, Determining a first overscan value by adding a first product to the length dimension between the first opening of the first Faraday cup at the first Faraday cup position and the first side of the intended beam scan region, The first product is obtained by multiplying the beam width of the ion beam by the first multiplier. The first multiplier is determined from a first predetermined threshold value of the first beam current of the ion beam at the first Faraday cup position. To determine the first overscan value, Determining a second overscan value by multiplying the beam width by a second multiplier, wherein the second multiplier is determined from a second predetermined threshold value of the second beam current of the ion beam at the second Faraday cup position. Methods that include...

2. Scanning the ion beam along the first and second sides of the intended beam scan region is Scanning the ion beam beyond the first side of the intended beam scan region until the ion beam has completely passed through the first opening of the first Faraday cup at the first Faraday cup position, Scanning the ion beam beyond the second side of the intended beam scan area until the ion beam has completely passed the second Faraday cup position. The method according to claim 1, including the method described in claim 1.

3. The method described above is: When the first beam current of the first Faraday cup reaches a predetermined first threshold, it is determined that the ion beam has completely passed through the first opening of the first Faraday cup, When the second beam current at the second Faraday cup position reaches the second predetermined threshold, it is determined that the ion beam has completely passed through the second Faraday cup position. The method according to claim 2, further comprising:

4. The method determines the optimal scan distance of the ion beam by summing the first overscan value, the second overscan value, and the diameter of the intended beam scan area. The method according to claim 3, further comprising:

5. Scanning the ion beam along the first and second sides of the intended beam scan region is First, in the first overscan region, the ion beam is positioned beyond the first Faraday cup, Moving the ion beam toward the first side of the intended beam scan region The method according to claim 2, including the method described in claim 2.

6. Scanning the ion beam along the first and second sides of the intended beam scan region is First, in the second overscan region, the ion beam is positioned beyond the second Faraday cup position, Moving the ion beam toward the second side of the intended beam scan region The method according to claim 5, further comprising:

7. An apparatus for optimizing the scanned beam distance of a spot ion beam, wherein the apparatus is: A beam scanner capable of operating to scan the spot ion beam with respect to an intended beam scan area, A Faraday cup along the first side of the intended beam scan region, A Faraday profiler along a second side of the intended beam scan region, wherein the Faraday cup is operable to measure a first beam current of the spot ion beam, and the Faraday profiler is operable to measure a second beam current of the spot ion beam. A beam calibration component comprising a controller and a memory, wherein the memory is Determining a first overscan value by adding a first product to the length dimension between the first opening of the Faraday cup at the Faraday cup position and the first side of the intended beam scan region, The first product is obtained by multiplying the beam width of the spot ion beam by the first multiplier. The first multiplier is determined from a first predetermined threshold value of the first beam current of the spot ion beam at the Faraday cup position. To determine the first overscan value, Determining a second overscan value by multiplying the beam width by a second multiplier, wherein the second multiplier is determined from a second predetermined threshold value of the second beam current of the spot ion beam at the Faraday profiler position. A beam calibration component comprising a calibration routine that can be operated on the controller that performs the following: A device equipped with the following features.

8. The apparatus according to claim 7, wherein the beam scanner is operable to scan the spot ion beam along the first and second sides of the intended beam scan region.

9. The beam scanner, which is operable to scan the spot ion beam along the first and second sides of the intended beam scan region, Scanning the spot ion beam beyond the first side of the intended beam scan area until the spot ion beam has completely passed through the first opening of the Faraday cup, Scanning the spot ion beam beyond the second side of the intended beam scan region until the spot ion beam has completely passed through the Faraday profiler. The apparatus according to claim 8, further operable to perform the following:

10. The calibration routine is as follows: When the first beam current of the Faraday cup reaches the first predetermined threshold, it is determined that the spot ion beam has completely passed through the first opening of the Faraday cup. When the second beam current of the Faraday profiler reaches the second predetermined threshold, it is determined that the spot ion beam has completely passed through the Faraday profiler. The apparatus according to claim 9, further operable on the controller to perform the following actions.

11. The calibration routine is as follows: The apparatus according to claim 7, wherein the controller is further operable to determine the optimal scan distance of the spot ion beam by summing the first overscan value, the second overscan value, and the diameter of the intended beam scan area.

12. The aforementioned beam scanner First, in the first overscan region, the spot ion beam is positioned beyond the Faraday cup, Moving the spot ion beam toward the first side of the intended beam scan region The apparatus according to claim 7, further operable to perform the following:

13. The aforementioned beam scanner First, in the second overscan region, the spot ion beam is positioned beyond the Faraday profiler, Moving the spot ion beam toward the second side of the intended beam scan region The apparatus according to claim 7, further operable to perform the following:

14. A non-temporary computer-readable storage medium, wherein the non-temporary computer-readable storage medium contains an instruction, and when the instruction is executed by a computer, the computer receives The beam scanner scans the spot ion beam with respect to the intended beam scan area, Measuring the first beam current of the spot ion beam in a first Faraday cup positioned along the first side of the intended beam scan region, and measuring the second beam current of the spot ion beam in a second Faraday cup positioned along the second side of the intended beam scan region, Determining a first overscan value by adding a first product to the length dimension between the first opening of the first Faraday cup at the first Faraday cup position and the first side of the intended beam scan region, The first product is obtained by multiplying the beam width of the spot ion beam by the first multiplier. The first multiplier is determined from a first predetermined threshold value of the first beam current of the spot ion beam at the first Faraday cup position. To determine the first overscan value, A non-temporary computer-readable storage medium that causes a second overscan value to be determined by multiplying the beam width by a second multiplier, wherein the second multiplier is determined from a second predetermined threshold value of the second beam current of the spot ion beam at a second Faraday cup position.

15. The non-temporary computer-readable storage medium according to claim 14, wherein the instruction further configures the computer to scan the spot ion beam along the first and second sides of the intended beam scan region.

16. The aforementioned instruction causes the computer to Scanning the spot ion beam beyond the first side of the intended beam scan area until the spot ion beam has completely passed through the first opening of the first Faraday cup, Scanning the spot ion beam beyond the second side of the intended beam scan area until the spot ion beam has completely passed through the second opening of the second Faraday cup. A non-temporary computer-readable storage medium according to claim 14, further configured to perform the following:

17. The aforementioned instruction causes the computer to When the first beam current of the first Faraday cup reaches a first predetermined threshold, it is determined that the spot ion beam has completely passed through the first opening of the first Faraday cup, When the second beam current of the second Faraday cup reaches the second predetermined threshold, it is determined that the spot ion beam has completely passed through the second opening of the second Faraday cup. A non-temporary computer-readable storage medium according to claim 16, further configured to perform the following:

18. The aforementioned instruction causes the computer to The non-temporary computer-readable storage medium according to claim 14, further configured to determine the optimal scan distance of the spot ion beam by summing the first overscan value, the second overscan value, and the diameter of the intended beam scan area.

19. The aforementioned instruction causes the computer to First, in the first overscan region, the spot ion beam is positioned beyond the first Faraday cup, When the spot ion beam moves toward the first side of the intended beam scan region, the first beam current is measured, First, in the second overscan region, the spot ion beam is positioned beyond the second Faraday cup, When the spot ion beam moves toward the second side of the intended beam scan region, the second beam current is measured. A non-temporary computer-readable storage medium according to claim 14, further configured to perform the following:

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