Ion source grid mesh structure and adjusting method thereof

Abstract

The invention discloses an ion source grid mesh structure and an adjusting method thereof, and the adjusting method comprises the steps: providing a grid mesh structure which comprises a screen grid and an acceleration grid, the screen grid comprises a plurality of first through holes which are periodically distributed, and the acceleration grid comprises a plurality of second through holes which are periodically distributed; installing the screen grid and the acceleration grid to enable the screen grid and the acceleration grid to be arranged perpendicular to a first direction, the screen grid and the acceleration grid are arranged along the first direction, and the first through holes and the second through holes are in one-to-one correspondence and are used for enabling an ion beam to pass through; according to the etching process requirement, at least one time of structure adjustment is carried out on the grid mesh structure, the structure adjustment comprises grid pitch adjustment, the grid pitch adjustment is used for controlling the distance between the middle area of the screen grid and the middle area of the acceleration grid, the stability of the grid mesh structure is improved, and the yield of the grid mesh structure is improved. The structure difference between the grid structures of different etching machines is reduced, and the stability of the etching process product performance is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular, to an ion source grid structure and an adjustment method thereof. Background Art

[0002] With the development of semiconductor devices, the wafer pattern accuracy has become higher and higher, and a series of dry etching technologies have been gradually developed. Commonly used ones include plasma etching, reactive ion etching, ion beam etching, etc. Among them, ion beam etching is an anisotropic etching process that can preferentially remove materials along a specific direction. As a pure physical etching method, ion beam etching has no selectivity for materials and can be used to etch almost any solid material, including metals, alloys, oxides, compounds, composite materials, semiconductors, insulators, superconductors, etc.

[0003] The ion source is a key component of ion beam etching, and the quality of the ion source directly affects the etching performance. Among them, the grid structure is a device in the ion source for beam extraction and shaping. A mesh electrode is made of graphite or molybdenum, etc., and is located at the front end of the ion source outlet. By changing the geometric characteristics, relative positions of the grid structure and controlling the potential distribution on the grid, ions can be extracted from the ion source discharge chamber and have a certain spatial concentration and spatial distribution shape.

[0004] However, the repeatability performance of the existing grid structure is poor, which poses a great challenge to the process repeatability of the chamber. Therefore, the performance of the existing grid structure needs to be further improved. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide an ion source grid structure and an adjustment method thereof to improve the performance of the formed grid structure.

[0006] To solve the above technical problem, the technical solution of the present invention provides an ion source grid structure, including: a grid structure, the grid structure includes a screen grid and an acceleration grid, the screen grid includes a plurality of first through holes arranged periodically, the acceleration grid includes a plurality of second through holes arranged periodically, after installation, both the screen grid and the acceleration grid are perpendicular to the first direction, the screen grid and the acceleration grid are arranged along the first direction, and the first through holes and the second through holes are in one-to-one correspondence for allowing the ion beam to pass through; a grid pitch adjustment structure, the grid pitch adjustment structure is used to control the distance between the middle regions of the screen grid and the acceleration grid.

[0007] Optionally, the grid pitch adjustment structure includes a first fixing device and a plurality of first spacer rings with different thickness specifications, and the first fixing device can fix any one of the first spacer rings between the screen grid and the acceleration grid.

[0008] Optionally, the thickness of the first spacing ring ranges from 1.0 mm to 4.2 mm; the exposed edge of the first spacing ring is a chamfered structure.

[0009] Optionally, the first fixing device includes a bolt and a nut that mates with the bolt. The bolt includes a head and a screw rod. The screw rod can pass through the first through hole, the first spacing ring, and the second through hole. The screen grid, the acceleration grid, and the first spacing ring can be fastened using the bolt and the nut.

[0010] Optionally, the diameter of the head is greater than the diameter of the screw rod; the ratio of the diameter of the head to the diameter of the screw rod ranges from 2 to 10; the ratio of the outer diameter of the nut to the diameter of the screw rod ranges from 2 to 10.

[0011] Optionally, the exposed edges of the head and the nut are both chamfered structures.

[0012] Optionally, the grid structure further includes a deceleration grid. The deceleration grid and the screen grid are respectively located on both sides of the acceleration grid. The deceleration grid includes a plurality of third through holes arranged in a periodic pattern. After installation, the first through hole, the second through hole, and the third through hole correspond to each other one by one; the grid pitch adjustment structure further includes a plurality of second spacing rings with different thickness specifications. The first fixing device can also fix any one of the second spacing rings between the middle region of the acceleration grid and the middle region of the deceleration grid.

[0013] Optionally, the thickness of the second spacing ring ranges from 1.0 mm to 4.2 mm; the exposed edge of the second spacing ring is a chamfered structure.

[0014] Optionally, the structure further includes: a shielding structure that can be detachably fixed to the first through hole or the second through hole and shields part of the first through hole or the second through hole.

[0015] Optionally, the shielding structure includes a shielding layer and a second fixing device fixedly connected to the shielding layer. The size of the shielding layer is larger than the size of a single first through hole or second through hole; the shielding layer is installed on the surface of the screen grid or the acceleration grid through the fixing device.

[0016] Optionally, the second fixing device includes a plurality of male-female fastener structures. Each male-female fastener structure includes a female fastener perpendicular to the surface of the shielding layer and fixedly connected to the shielding layer, and a male fastener that mates with the female fastener; each female fastener can pass through the first through hole to install the shielding layer on the surface of the screen grid, or each female fastener can pass through the second through hole to install the shielding layer on the surface of the acceleration grid.

[0017] Optionally, an interference fit is provided between the male buckle and the female buckle.

[0018] Correspondingly, the technical solution of the present invention further provides a method for adjusting an ion source grid structure, including: providing a grid structure, the grid structure including a screen grid and an acceleration grid, the screen grid including a plurality of first through holes arranged periodically, and the acceleration grid including a plurality of second through holes arranged periodically; installing the grid structure such that both the screen grid and the acceleration grid are arranged perpendicular to a first direction, the screen grid and the acceleration grid are arranged along the first direction, and the first through holes and the second through holes correspond one by one for allowing an ion beam to pass through; performing at least one structural adjustment on the grid structure according to the requirements of an etching process, the structural adjustment including a grid pitch adjustment for controlling the distance between a middle region of the screen grid and a middle region of the acceleration grid.

[0019] Optionally, the grid pitch adjustment method includes: providing a grid pitch adjustment structure, the grid pitch adjustment structure including a first fixing device and a plurality of first spacer rings with different thickness specifications, the first fixing device being capable of fixing any one of the first spacer rings between the screen grid and the acceleration grid; obtaining a first adjustment point from the middle region of the screen grid and a second adjustment point from the middle region of the acceleration grid, the first adjustment point and the second adjustment point being arranged along the first direction, and obtaining a first target distance between the first adjustment point and the second adjustment point; selecting a first spacer ring corresponding in thickness to the first target distance according to the first target distance; fixing the selected first spacer ring between the first adjustment point and the second adjustment point; and fixing the selected first spacer ring between the screen grid and the acceleration grid through the first fixing device.

[0020] Optionally, the first fixing device includes a bolt and a nut cooperating with the bolt, the bolt including a head and a screw rod, the screw rod being capable of passing through the first through hole, the first spacer ring, and the second through hole, and the screen grid, the acceleration grid, and the first spacer ring being fastened by the bolt and the nut.

[0021] Optionally, the grid structure further includes a deceleration grid, and the deceleration grid includes a plurality of third through holes arranged periodically; after installation, the deceleration grid and the screen grid are respectively located on both sides of the acceleration grid, and the first through hole, the second through hole, and the third through hole correspond to each other one by one; the grid pitch adjustment structure further includes a plurality of second spacer rings with different thickness specifications, and the first fixing device can also fix any one of the second spacer rings between the acceleration grid and the deceleration grid; the grid pitch adjustment method further includes: obtaining a third adjustment point from the middle area of the deceleration grid, arranging the first adjustment point, the second adjustment point, and the third adjustment point along the first direction, and obtaining a second target distance between the acceleration grid and the deceleration grid; according to the second target distance, selecting a second spacer ring with a thickness corresponding to the second target distance; fixing the second spacer ring between the second adjustment point and the third adjustment point; and fixing the selected second spacer ring between the acceleration grid and the deceleration grid through the first fixing device.

[0022] Optionally, according to the requirements of the etching process, the method for performing at least one structural adjustment on the grid structure includes: obtaining the first process parameter setting when the etching machine reaches the optimal uniformity; according to the first process parameter setting, determining whether the first process parameter setting meets the requirements of the preset process parameter range; when the first process parameter setting does not meet the requirements of the preset process parameter range, performing the grid pitch adjustment.

[0023] Optionally, according to the requirements of the etching process, the method for performing at least one structural adjustment on the grid structure further includes: performing local shielding adjustment on the grid structure according to the requirements of the etching process to shield part of the first through holes or the second through holes.

[0024] Optionally, the method for performing local shielding adjustment on the grid structure according to the requirements of the etching process includes: obtaining the second process parameter setting when the etching machine reaches the optimal uniformity; according to the second process parameter setting, determining whether the second process parameter setting meets the requirements of the preset process parameter range; when the second process parameter setting does not meet the requirements of the preset process parameter range, performing the local shielding adjustment.

[0025] Optionally, after the local shielding adjustment, it further includes: obtaining the third process parameter setting when the etching machine reaches the optimal uniformity; according to the third process parameter setting, determining whether the third process parameter setting meets the requirements of the preset process parameter range; when the third process parameter setting does not meet the requirements of the preset process parameter range, continuing the structural adjustment until the second process parameter setting or the third process parameter setting meets the requirements of the preset process parameter range.

[0026] Optionally, the method for local occlusion adjustment includes: obtaining a target occlusion area on the screen grid or the acceleration grid; obtaining a corresponding occlusion structure according to the target occlusion area, the occlusion structure being detachable and fixable to the first through hole or the second through hole of the target occlusion area, and occluding part of the first through hole or the second through hole; and installing the occlusion structure on the surface of the screen grid or the acceleration grid of the target occlusion area.

[0027] Optionally, the occlusion structure includes an occlusion layer and a second fixing device fixedly connected to the occlusion layer, the size of the occlusion layer being larger than the size of a single first through hole or second through hole; the occlusion layer is installed on the surface of the screen grid or the acceleration grid of the target occlusion area through the second fixing device.

[0028] Optionally, the second fixing device includes a plurality of male-female fastener structures, each male-female fastener structure including a female fastener perpendicular to the surface of the occlusion layer and fixedly connected to the occlusion layer, and a male fastener cooperating with the female fastener; each female fastener can pass through the first through hole to install the occlusion layer on the surface of the screen grid, or each female fastener can pass through the second through hole to install the occlusion layer on the surface of the acceleration grid.

[0029] Optionally, the method for installing the occlusion layer on the surface of the screen grid or the acceleration grid of the target occlusion area includes: making an interference fit between the male fastener and the female fastener.

[0030] Optionally, the installation includes edge-fixing the screen grid and the acceleration grid respectively by an edge-fixing method.

[0031] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0032] In the method for adjusting the ion source grid structure provided by the technical solution of the present invention, at least one structural adjustment is performed on the grid structure according to the requirements of the etching process. The structural adjustment includes grid pitch adjustment, and the grid pitch adjustment is used to control the distance between the middle area of the screen grid and the middle area of the acceleration grid. The grid pitch adjustment structure is placed in the middle area of the grid structure, and the screen grid and the acceleration grid in the free state in the middle area are constrained, which is beneficial to improving the stability of the grid structure, reducing the structural differences between the grid structures of different etching machines, and improving the stability of the performance of the etching process products; in addition, by controlling the distance between the screen grid and the acceleration grid, it is further beneficial to control the overall output energy and divergence angle of the ion beam, and improve the stability of the performance of the etching process products.

[0033] Furthermore, the grid pitch adjustment structure includes a first fixing device and a number of first spacer rings with different thickness specifications. By using first spacer rings with different thicknesses, the distance between the screen grid and the acceleration grid can be further precisely controlled.

[0034] Furthermore, the structure adjustment further includes: according to the requirements of the etching process, locally shielding and adjusting the grid structure to shield part of the first through-holes or the second through-holes, changing the distribution state of the ion beam in a local area, and achieving precise control of the output performance of the ion beam.

[0035] Furthermore, when the setting of the third process parameter does not meet the requirements of the preset process parameter range, continue the structure adjustment until the setting of the second process parameter or the third process parameter meets the requirements of the preset process parameter range, which is beneficial to improving the repeatability of the process between different etching machines.

[0036] In the ion source grid structure provided by the technical solution of the present invention, the grid pitch adjustment structure is used to control the distance between the middle regions of the screen grid and the acceleration grid. The target adjustment point is located in the middle region of the grid structure in the first direction, binding the screen grid and the acceleration grid in the middle region in a free state, which is beneficial to improving the stability of the grid structure, reducing the structural differences between the grid structures of different etching machines, and improving the stability of the performance of the etching process products; in addition, by controlling the distance between the screen grid and the acceleration grid, it is further beneficial to control the overall output energy and divergence angle of the ion beam, and improve the stability of the performance of the etching process products.

[0037] Furthermore, the grid pitch adjustment structure includes a first fixing device and a number of first spacer rings with different thickness specifications. By using first spacer rings with different thicknesses, the distance between the screen grid and the acceleration grid can be further precisely controlled.

[0038] Furthermore, the structure further includes a shielding structure, which can be detachably fixed to the first through-holes or the second through-holes in the target shielding area, and shield part of the first through-holes or the second through-holes, changing the distribution state of the ion beam in a local area, and achieving precise control of the output performance of the ion beam.

[0039] Furthermore, the diameter of the head is greater than the diameter of the screw; the ratio range of the diameter of the head to the diameter of the screw is 2 to 10; the ratio range of the outer diameter of the nut to the diameter of the screw is 2 to 10. Making the sizes of the head and the nut larger is beneficial to protecting the first spacer ring from being back-plated during operation, thereby reducing the probability of direct conduction between the screen grid and the acceleration grid.

[0040] Furthermore, the edges of the head and the nut that are exposed are both chamfered structures, and the chamfered structures are conducive to reducing the probability of arcing during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram of an ion source structure;

[0042] Figures 2 to 10 is a schematic diagram of the structures of the steps of the method for adjusting the ion source grid structure according to an embodiment of the present invention;

[0043] Figure 11 is a flowchart of adjusting the grid structure according to an embodiment of the present invention;

[0044] Figure 12 is a schematic diagram of the structure of the second fixing device according to another embodiment of the present invention;

[0045] Figure 13 is a schematic diagram of the structure of the second fixing device according to still another embodiment of the present invention. DETAILED DESCRIPTION

[0046] It should be noted that the "surface" and "upper" in this specification are used to describe the relative positional relationship in space and do not limit whether there is direct contact.

[0047] As described in the background art, the performance of the existing grid structure needs to be further improved. Now, an ion source structure is combined for illustration and analysis.

[0048] Figure 1 is a schematic diagram of an ion source structure.

[0049] Please refer to Figure 1 , before the ion beam etching operation, an inert gas such as Ar, Kr, or Xe is filled into the discharge chamber 101 through the gas inlet 100. During the ion beam etching operation, under the action of the radio frequency coil 102, the gas in the discharge chamber 101 is ionized to form a uniform plasma, and then the grid structure extracts and accelerates the plasma in a beam shape. The ion beam 103 with a certain energy enters the reaction chamber 104 and bombards the surface of the wafer 106 on the wafer stage 105, causing the material atoms to sputter, achieving the etching purpose, and thus obtaining an etching pattern.

[0050] The above-mentioned grid structure generally consists of two or three grids. Among them, the screen grid 107 and the acceleration grid 108 are necessary components for extracting and accelerating ions. The deceleration grid 109 has a potential of 0, which can effectively protect the acceleration grid, reduce the divergence angle, and adjust the ion beam current trajectory. There are a large number of small holes arranged in a honeycomb pattern on each grid. The fixing method of each grid is in a state of edge fixation and middle freedom. This fixing method is greatly limited by factors such as the stiffness of the grid body, the machining accuracy and matching of the fixing parts, and the thermal expansion and contraction of the grid, resulting in poor repeatability between the grid structures of different etching machines and posing a great challenge to process repeatability.

[0051] To solve the above problems, in an ion source grid structure and its adjustment method provided by the present invention, according to the requirements of the etching process, at least one structural adjustment is performed on the grid structure. The structural adjustment includes grid pitch adjustment. The grid pitch adjustment is used to control the distance between the middle regions of the screen grid and the acceleration grid. The grid pitch adjustment structure is placed in the middle region of the grid structure, and the screen grid and the acceleration grid in the middle region in a free state are constrained, which is beneficial to improving the stability of the grid structure, reducing the structural differences between the grid structures of different etching machines, and improving the stability of the performance of the etching process products. In addition, by controlling the distance between the screen grid and the acceleration grid, it is further beneficial to control the overall output energy and divergence angle of the ion beam, and improve the stability of the performance of the etching process products.

[0052] To make the above objects, features, and beneficial effects of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings.

[0053] Figures 2 to 10 It is a schematic structural diagram of each step of the adjustment method of the ion source grid structure in an embodiment of the present invention.

[0054] Please refer to Figure 2 and Figure 3 , Figure 2 It is a top view structural diagram of the screen grid 20 (acceleration grid 30, deceleration grid 40), Figure 3 For Figure 2 The enlarged cross-sectional structural diagram along the EE1 direction of the local area (at the dotted box P1) in

[0055] In this embodiment, both the screen grid 20 and the acceleration grid 30 have a middle region II and an edge region I. Among them, the edge region I has an edge fixing device (not shown in the figure) for respectively performing edge fixation on the screen grid and the acceleration grid.

[0056] In this embodiment, the grid structure further includes a deceleration grid 40, and the deceleration grid 40 includes a plurality of third through holes 401 arranged periodically. Specifically, the deceleration grid 40 also correspondingly has a middle region II and an edge region I.

[0057] In this embodiment, a plurality of the first through holes 201, a plurality of the second through holes 301, and a plurality of the third through holes 401 are all arranged in a honeycomb pattern, which is used to provide a relatively uniform ion beam distribution. In other embodiments, other periodic arrangement forms may be adopted.

[0058] Please continue to refer to Figure 3 , install the machine so that both the screen grid 20 and the acceleration grid 30 are arranged perpendicular to the first direction X. The screen grid 20 and the acceleration grid 30 are arranged along the first direction X, and the first through holes 201 and the second through holes 301 correspond to each other one by one for the ion beam to pass through.

[0059] In this embodiment, the installation of the machine includes respectively fixing the edges of the screen grid 20 and the acceleration grid 30 by means of edge fixing. Specifically, the deceleration grid 40 is also edge-fixed by means of edge fixing.

[0060] In this embodiment, after the installation of the machine, the deceleration grid 40 and the screen grid 20 are respectively located on both sides of the acceleration grid 30, and the first through holes 201, the second through holes 301, and the third through holes 401 correspond to each other one by one.

[0061] It should be noted that after the installation of the machine, the screen grid 20 is closest to the discharge chamber (not shown in the figure) of the etching machine tool, the deceleration grid 40 is far from the discharge chamber, and is closest to the wafer to be etched.

[0062] Subsequently, according to the requirements of the etching process, at least one structural adjustment is performed on the grid structure. The structural adjustment includes grid pitch adjustment, and the grid pitch adjustment is used to control the distance between the middle region of the screen grid and the middle region of the acceleration grid.

[0063] Figure 11 This is a flowchart of the structural adjustment of the grid structure in an embodiment of the present invention.

[0064] Please refer to Figure 11 , according to the requirements of the etching process, the method for performing at least one structural adjustment on the grid structure includes the following processes:

[0065] Step S701, obtain the first process parameter setting when the etching machine tool reaches the optimal uniformity;

[0066] Step S702, determine whether the first process parameter setting meets the requirements of the preset process parameter range according to the first process parameter setting;

[0067] Step S703: When the setting of the first process parameter does not meet the requirements of the preset process parameter range, perform the grid pitch adjustment.

[0068] Specifically, when the setting of the first process parameter does not meet the requirements of the preset process parameter range, perform the grid pitch adjustment on the grid structure according to the difference between the setting of the first process parameter and the preset process parameter range.

[0069] It should be noted that the first process parameter, the preset process parameter, and the second process parameter and the second process parameter to be mentioned later may include parameters such as radio frequency power, etching gas flow rate, pressure, and process time.

[0070] The method for the grid pitch adjustment will be described in detail below.

[0071] Please refer to Figure 4 , a grid pitch adjustment structure is provided. The grid pitch adjustment structure includes a first fixing device and a plurality of first spacer rings 501 with different thickness specifications. The first fixing device can fix any one of the first spacer rings 501 between the screen grid 20 (as shown in Figure 3 ) and the accelerating grid 30 (as shown in Figure 3 ).

[0072] In this embodiment, the thickness m1 of the first spacer ring 501 ranges from 1.0 mm to 4.2 mm.

[0073] In this embodiment, the first fixing device includes a bolt 503 and a nut 504 that mates with the bolt 503. The bolt 503 includes a head 503a and a screw rod 503b. The screw rod 503b can pass through the first through hole 201, the first spacer ring 501, and the second through hole 301. The screen grid 20, the accelerating grid 30, and the first spacer ring 501 can be fastened by the bolt 503 and the nut 504.

[0074] In this embodiment, the diameter of the head 503a is greater than the diameter of the screw rod 503b; the ratio of the diameter of the head 503a to the diameter of the screw rod 503b ranges from 2 to 10; the ratio of the outer diameter of the nut 504 to the diameter of the screw rod 503b ranges from 2 to 10. Making the sizes of the head 503a and the nut 504 larger is beneficial to protecting the first spacer ring 501 from being back-plated during operation, thereby reducing the probability of direct conduction between the screen grid 20 and the accelerating grid 30.

[0075] In this embodiment, the pitch adjustment structure further includes a plurality of second fixed distance rings 502 with different thickness specifications, and the first fixing device can also fix any one of the second fixed distance rings 502 between the acceleration grid 30 and the deceleration grid 40 (as Figure 3 shown).

[0076] In this embodiment, the thickness m2 of the second fixed distance ring 502 ranges from 1.0 mm to 4.2 mm.

[0077] Furthermore, the sizes of the head 503a and the nut 504 are made larger, which is beneficial to protecting the second fixed distance ring 502 from being reverse-plated during operation, thereby reducing the probability of direct conduction between the deceleration grid 40 and the acceleration grid 30.

[0078] After subsequent pitch adjustment, the exposed edges of the head 503a and the nut 504 are chamfered structures; the exposed edge of the first fixed distance ring 501 is a chamfered structure; the exposed edge of the second fixed distance ring 502 is also a chamfered structure. The chamfered structure is beneficial to reducing the probability of arcing during operation.

[0079] Please refer to Figure 5 and Figure 6 , Figure 5 The view directions of Figure 2 are the same as Figure 6 , and the view directions of Figure 3 are the same as

[0080] In this embodiment, a third adjustment point C is also obtained from the middle region II of the deceleration grid 40. The first adjustment point A, the second adjustment point B, and the third adjustment point C are arranged along the first direction X, and a second target distance h2 between the acceleration grid 30 and the deceleration grid 40 is obtained; according to the second target distance h2, a second fixed distance ring 502 with a thickness corresponding to the second target distance h2 is selected.

[0081] The first adjustment point A, the second adjustment point B, and the third adjustment point C are used to position the position of the pitch adjustment. It should be noted that during the pitch adjustment of the current time, the position of the pitch adjustment and the selection of the first target distance h1 can be adjusted according to information such as the difference between the first process parameter setting during the pitch adjustment of the current time and the preset process parameter range.

[0082] Here, for the convenience of description, the selected position for pitch adjustment is one (as shown by the dashed box P1 in Figure 5 ), and the first adjustment point A, the second adjustment point B, and the third adjustment point C are all located at the center of the middle region II of their respective grid.

[0083] Please continue to refer to Figure 5 and Figure 6 , and fix the selected first fixed-distance ring 501 between the first adjustment point A and the second adjustment point B; fix the selected first fixed-distance ring 501 between the screen grid 20 and the acceleration grid 30 through the first fixing device.

[0084] So far, the pitch adjustment is used to control the distance between the middle region II of the screen grid 20 and the middle region II of the acceleration grid 30. Place the pitch adjustment structure in the middle region II of the grid structure to restrain the screen grid and the acceleration grid in the free state in the middle region, which is beneficial to improving the stability of the grid structure, reducing the structural differences between the grid structures of different etching machines, and improving the stability of the performance of the etched process products; in addition, by controlling the distance between the screen grid 20 and the acceleration grid 30, it is further beneficial to control the overall output energy and divergence angle of the ion beam, and improve the stability of the performance of the etched process products.

[0085] Furthermore, the distance between the screen grid 20 and the acceleration grid 30 can be further accurately controlled by the first fixed-distance rings 501 with different thicknesses.

[0086] In this embodiment, the selected second fixed-distance ring 502 is also fixed between the second adjustment point B and the third adjustment point C; the selected second fixed-distance ring 502 is also fixed between the acceleration grid 30 and the deceleration grid 40 through the first fixing device. The distance between the acceleration grid 30 and the deceleration grid 40 can be further accurately controlled by the second fixed-distance rings 502 with different thicknesses.

[0087] In this embodiment, the method for performing at least one structural adjustment on the grid structure according to the requirements of the etching process further includes: performing local shielding adjustment on the grid structure according to the requirements of the etching process to shield part of the first through hole 201 or the second through hole 301.

[0088] Here, the local shielding adjustment is used to change the distribution state of the local area of the ion beam and achieve precise control of the output performance of the ion beam.

[0089] Specifically, please continue to refer to Figure 11 , and the method for performing local shielding adjustment on the grid structure according to the requirements of the etching process further includes the following steps:

[0090] Step S704, obtain the second process parameter setting when the etcher reaches the optimal uniformity;

[0091] Step S705, determine whether the second process parameter setting meets the requirements of the preset process parameter range according to the second process parameter setting;

[0092] Step S706, when the second process parameter setting does not meet the requirements of the preset process parameter range, perform the local shielding adjustment.

[0093] More specifically, please continue to refer to Figure 11 , after the local shielding adjustment, the following steps are further included:

[0094] Step S707, obtain the third process parameter setting when the etcher reaches the optimal uniformity;

[0095] Step S708, determine whether the third process parameter setting meets the requirements of the preset process parameter range according to the third process parameter setting;

[0096] When the third process parameter setting does not meet the requirements of the preset process parameter range, continue the structure adjustment until the second process parameter setting or the third process parameter setting meets the requirements of the preset process parameter range.

[0097] Here, making the second process parameter setting or the third process parameter setting meet the requirements of the preset process parameter range is beneficial to improving the repeatability of the process between different etchers.

[0098] The method of the local shielding adjustment is described in detail below.

[0099] Please refer to Figure 7 , Figure 7 The view direction of Figure 2 is the same as that of

[0100] Here, it should be noted that after installation, it is easier to operate the shielded part of the first through hole 201 than the shielded part of the second through hole 301. Therefore, in this embodiment, the target shielding area P2 is obtained on the screen grid 20.

[0101] Furthermore, it should be noted that Figure 7 The several target shielding areas P2 shown in

[0102] Please continue to refer to Figure 7 and refer to Figure 8 According to the target occlusion area P2, obtain a corresponding occlusion structure. The occlusion structure is detachable and fixable to the first through-hole 201 or the second through-hole 301 of the target occlusion area P2, and occludes part of the first through-hole 201 or the second through-hole 301.

[0103] In this embodiment, for the convenience of operation, the first through-hole 201 is occluded.

[0104] In this embodiment, the occlusion structure includes an occlusion layer 601 and a second fixing device fixedly connected to the occlusion layer 601. The size of the occlusion layer 601 is larger than the size of a single first through-hole 201 or second through-hole 301; the occlusion layer 601 is installed on the surface of the screen grid 20 or the acceleration grid 30 of the target occlusion area P2 through the second fixing device.

[0105] The second fixing device includes a plurality of male-female buckle structures. Each male-female buckle structure includes a female buckle 602 perpendicular to the surface of the occlusion layer 601 and fixedly connected to the occlusion layer 601, and a male buckle 603 cooperating with the female buckle 602; each female buckle 602 can pass through the first through-hole 201 to install the occlusion layer 601 on the surface of the screen grid 20, or each female buckle 602 can pass through the second through-hole 301 to install the occlusion layer 601 on the surface of the acceleration grid 30.

[0106] In this embodiment, the end of the female buckle 602 has a groove 604, and the male buckle 603 is annular and can be embedded into the groove 604 to achieve fastening. In other embodiments, the male-female buckle structure can adopt other structures.

[0107] In this embodiment, one occlusion layer 601 corresponds to one female buckle 602 and one male buckle 603 to achieve occlusion of a single hole. In other embodiments, one occlusion layer corresponds to a plurality of male-female buckle structures to achieve occlusion of multiple holes.

[0108] Please refer to Figure 9 and Figure 10 , Figure 9 The view direction of Figure 2 is the same as that of Figure 10 The view direction of Figure 3 is the same as that of

[0109] Specifically, make the female buckle 602 pass through the first through-hole 201 or the second through-hole 301, and use the male buckle 603 for fastening.

[0110] In this embodiment, for the convenience of operation, the shielding structure is installed on the surface of the screen grid 20 in the target shielding area P2. More specifically, the female buckle 602 is passed through the first through hole 201, and the male buckle 603 is used for fastening.

[0111] Specifically, the method for installing the shielding layer 601 on the surface of the screen grid 20 or the acceleration grid 30 in the target shielding area P2 includes: making an interference fit between the male buckle 603 and the female buckle 602. The interference fit is beneficial to improving the firmness of the fit between the male buckle 603 and the female buckle 602.

[0112] Correspondingly, the embodiment of the present invention further provides an ion source grid structure formed by the above method. Please continue to refer to Figure 2 、 Figure 3 、 9 and Figure 10 , a grid structure, the grid structure includes a screen grid 20 and an acceleration grid 30. The screen grid 20 includes a plurality of first through holes 201 arranged periodically, and the acceleration grid 30 includes a plurality of second through holes 301 arranged periodically. After installation, both the screen grid 20 and the acceleration grid 30 are perpendicular to the first direction X. The screen grid 20 and the acceleration grid 30 are arranged along the first direction X, and the first through holes 201 and the second through holes 301 are in one-to-one correspondence for allowing the ion beam to pass through; a grid pitch adjustment structure for controlling the distance between the middle region II of the screen grid 20 and the middle region II of the acceleration grid 30.

[0113] Here, the grid pitch adjustment structure is used to control the distance between the middle region II of the screen grid 20 and the middle region II of the acceleration grid 30. The grid pitch adjustment structure is placed in the middle region II of the grid structure to constrain the screen grid and the acceleration grid in the middle region in a free state, which is beneficial to improving the stability of the grid structure, reducing the structural differences between the grid structures of different etching machines, and improving the stability of the performance of the etching process products. In addition, by controlling the distance between the screen grid 20 and the acceleration grid 30, it is further beneficial to control the overall output energy and divergence angle of the ion beam, and improve the stability of the performance of the etching process products.

[0114] In this embodiment, the grid pitch adjustment structure includes a first fixing device and a plurality of first spacer rings 501 with different thickness specifications. The first fixing device can fix any one of the first spacer rings 501 between the screen grid 20 and the acceleration grid 30. The distance between the screen grid 20 and the acceleration grid 30 can be further accurately controlled by the first spacer rings 501 with different thicknesses.

[0115] In this embodiment, the thickness m1 of the first spacer ring 501 ranges from 1.0 mm to 4.2 mm.

[0116] In this embodiment, the exposed edge of the first spacing ring 501 is a chamfered structure. This chamfered structure is conducive to reducing the probability of arcing during operation.

[0117] In this embodiment, the first fixing device includes a bolt 503 and a nut 504 that mates with the bolt 503. The bolt 503 includes a head 503a and a screw rod 503b. The screw rod 503b can pass through the first through hole 201, the first spacing ring 501, and the second through hole 301. The screen grid 20, the accelerating grid 30, and the first spacing ring 501 can be fastened using the bolt 503 and the nut 504.

[0118] In this embodiment, the diameter of the head 503a is greater than the diameter of the screw rod 503b; the ratio of the diameter of the head 503a to the diameter of the screw rod 503b ranges from 2 to 10; the ratio of the outer diameter of the nut 504 to the diameter of the screw rod 503b ranges from 2 to 10. Making the sizes of the head 503a and the nut 504 larger is conducive to protecting the first spacing ring 501 from reverse plating during operation, thereby reducing the probability of direct conduction between the screen grid 20 and the accelerating grid 30.

[0119] In this embodiment, the exposed edges of the head 503a and the nut 504 are both chamfered structures. These chamfered structures are conducive to reducing the probability of arcing during operation.

[0120] In this embodiment, the grid structure further includes a decelerating grid 40. The decelerating grid 40 and the screen grid 20 are respectively located on both sides of the accelerating grid 30. The decelerating grid 40 includes a number of third through holes 401 arranged in a periodic pattern. After installation, the first through hole 201, the second through hole 301, and the third through hole 401 correspond to each other one by one; the grid pitch adjustment structure further includes a number of second spacing rings 502 with different thickness specifications. The first fixing device can also fix any one of the second spacing rings 502 between the middle region II of the accelerating grid 30 and the middle region II of the decelerating grid 40.

[0121] In this embodiment, the thickness range of the second spacing ring 502 is from 1.0 mm to 4.2 mm; the exposed edge of the second spacing ring 502 is a chamfered structure. This chamfered structure is conducive to reducing the probability of arcing during operation.

[0122] In this embodiment, the structure further includes: an occlusion structure, which is detachably and fixedly attached to the first through hole 201 or the second through hole 301, and occludes part of the first through hole 201 or the second through hole 301. The occlusion structure is used to change the distribution state of the local area of the ion beam and achieve precise control of the output performance of the ion beam.

[0123] In this embodiment, the occlusion structure includes an occlusion layer 601 and a second fixing device fixedly connected to the occlusion layer 601. The size of the occlusion layer 601 is larger than the size of a single first through hole 201 or second through hole 301; the occlusion layer 601 is installed on the surface of the screen grid 20 or the acceleration grid 30 through the fixing device.

[0124] In this embodiment, the second fixing device includes a plurality of male-female snap structures. Each male-female snap structure includes a female snap 602 perpendicular to the surface of the occlusion layer 601 and fixedly connected to the occlusion layer 601, and a male snap 603 that cooperates with the female snap 602; each female snap 602 can pass through the first through hole 201 to install the occlusion layer 601 on the surface of the screen grid 20, or each female snap 602 can pass through the second through hole 301 to install the occlusion layer 601 on the surface of the acceleration grid 30.

[0125] In this embodiment, there is an interference fit between the female snap 602 and the male snap 603.

[0126] In this embodiment, the second fixing device includes one male-female snap structure. In other embodiments, the second fixing device may include a plurality of male-female snap structures to achieve close contact between the surface of the occlusion layer and the surface of the screen grid or the acceleration grid.

[0127] Figure 12 It is a schematic structural diagram of the second fixing device in another embodiment of the present invention.

[0128] The difference between this embodiment and the previous embodiment mainly lies in that: the occlusion structure includes an occlusion layer 801 and a second fixing device fixedly connected to the occlusion layer 801; the second fixing device includes three male-female snap structures. Each male-female snap structure includes a female snap 802 perpendicular to the surface of the occlusion layer 801 and fixedly connected to the occlusion layer 801, and a male snap 803 that cooperates with the female snap 802.

[0129] Figure 13 It is a schematic structural diagram of the second fixing device in yet another embodiment of the present invention.

[0130] The differences between this embodiment and the previous one mainly lie in that: the shielding structure includes a shielding layer 901 and a second fixing device fixedly connected to the shielding layer 901; the second fixing device includes five snap-fastener structures, and each snap-fastener structure includes a female snap 902 perpendicular to the surface of the shielding layer 901 and fixedly connected to the shielding layer 901, and a male snap 903 that cooperates with the female snap 902.

[0131] It should be noted that Figure 12 and Figure 13 only for illustration, in the second fixing device, the shielding layer is used to shield part of the first through holes or the second through holes, and the size of the selected shielding layer is related to the size of the area to be shielded. Each snap-fastener is used to mount the shielding layer on the surface of the screen grid or the acceleration grid, and to achieve close contact between the surface of the shielding layer and the surface of the screen grid or the acceleration grid; the projected area of the shielding layer on the surface of the screen grid or the acceleration grid can be in the shape of a straight line, a circle, an ellipse, etc., and no limitation is made here.

[0132] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. An ion source grid structure, characterized in that, Comprising: A grid structure, the grid structure includes a screen grid and an acceleration grid, the screen grid includes a number of first through-holes arranged periodically, the acceleration grid includes a number of second through-holes arranged periodically, after installation, the screen grid and the acceleration grid are both perpendicular to the first direction, the screen grid and the acceleration grid are arranged along the first direction, and the first through-holes and the second through-holes are in one-to-one correspondence for allowing an ion beam to pass through; A grid pitch adjustment structure, the grid pitch adjustment structure is used to control the distance between the middle regions of the screen grid and the acceleration grid.

2. The ion source grid structure according to claim 1, characterized in that, The grid pitch adjustment structure includes a first fixing device and a number of first spacer rings with different thickness specifications, and the first fixing device can fix any one of the first spacer rings between the screen grid and the acceleration grid.

3. The ion source grid structure according to claim 2, characterized in that, The thickness range of the first spacer ring is from 1.0 mm to 4.2 mm; the exposed edges of the first spacer ring are chamfered structures.

4. The ion source grid structure according to claim 2, characterized in that, The first fixing device includes a bolt and a nut that mates with the bolt, the bolt includes a head and a screw rod, the screw rod can pass through the first through-hole, the first spacer ring and the second through-hole, and the screen grid, the acceleration grid and the first spacer ring can be fastened by the bolt and the nut.

5. The ion source grid structure according to claim 4, characterized in that, The diameter of the head is greater than the diameter of the screw rod; the ratio of the diameter of the head to the diameter of the screw rod ranges from 2 to 10; The ratio of the outer diameter of the nut to the diameter of the screw rod ranges from 2 to 10.

6. The ion source grid structure according to claim 4, characterized in that, The exposed edges of the head and the nut are both chamfered structures.

7. The ion source grid structure according to claim 2, characterized in that, The grid structure further includes a deceleration grid, the deceleration grid and the screen grid are respectively located on both sides of the acceleration grid, the deceleration grid includes a number of third through-holes arranged periodically, after installation, the first through-hole, the second through-hole and the third through-hole are in one-to-one correspondence with each other; the grid pitch adjustment structure further includes a number of second spacer rings with different thickness specifications, and the first fixing device can also fix any one of the second spacer rings between the middle regions of the acceleration grid and the deceleration grid.

8. The ion source grid structure according to claim 7, characterized in that, The thickness range of the second spacer ring is from 1.0 mm to 4.2 mm; the exposed edges of the second spacer ring are chamfered structures.

9. The ion source grid structure according to claim 1, characterized in that, The structure further includes: a shielding structure, the shielding structure is detachable and fixable to the first through-hole or the second through-hole, and shields a part of the first through-hole or the second through-hole.

10. The ion source grid structure according to claim 9, characterized in that, The shielding structure includes a shielding layer and a second fixing device fixedly connected to the shielding layer, the size of the shielding layer is larger than the size of a single first through-hole or second through-hole; the shielding layer is installed on the surface of the screen grid or the acceleration grid through the fixing device.

11. The ion source grid structure according to claim 10, characterized in that, The second fixing device includes a number of male-female fastener structures, each male-female fastener structure includes a female fastener perpendicular to the surface of the shielding layer and fixedly connected to the shielding layer, and a male fastener that mates with the female fastener; each female fastener can pass through the first through-hole to install the shielding layer on the surface of the screen grid, or each female fastener can pass through the second through-hole to install the shielding layer on the surface of the acceleration grid.

12. The ion source grid structure according to claim 11, characterized in that, There is an interference fit between the male fastener and the female fastener.

13. A method for adjusting an ion source grid structure, characterized in that, Comprising: Provide a grid structure, the grid structure includes a screen grid and an acceleration grid, the screen grid includes a number of first through holes arranged periodically, and the acceleration grid includes a number of second through holes arranged periodically; Install the machine so that both the screen grid and the acceleration grid are arranged perpendicular to the first direction, the screen grid and the acceleration grid are arranged along the first direction, and the first through holes and the second through holes correspond one by one for the ion beam to pass through; According to the requirements of the etching process, perform at least one structural adjustment on the grid structure. The structural adjustment includes grid pitch adjustment, and the grid pitch adjustment is used to control the distance between the middle regions of the screen grid and the acceleration grid.

14. The method for adjusting an ion source grid structure according to claim 13, characterized in that, The grid pitch adjustment method includes: providing a grid pitch adjustment structure, the grid pitch adjustment structure includes a first fixing device and a number of first spacer rings with different thickness specifications, and the first fixing device can fix any one of the first spacer rings between the screen grid and the acceleration grid; obtain a first adjustment point from the middle region of the screen grid, obtain a second adjustment point from the middle region of the acceleration grid, the first adjustment point and the second adjustment point are arranged along the first direction, and obtain the first target distance between the first adjustment point and the second adjustment point; according to the first target distance, select a first spacer ring with a thickness corresponding to the first target distance; fix the selected first spacer ring between the first adjustment point and the second adjustment point; and fix the selected first spacer ring between the screen grid and the acceleration grid through the first fixing device.

15. The method for adjusting an ion source grid structure according to claim 14, characterized in that, The first fixing device includes a bolt and a nut that mates with the bolt. The bolt includes a head and a screw rod. The screw rod can pass through the first through hole, the first spacer ring, and the second through hole, and the screen grid, the acceleration grid, and the first spacer ring can be fastened by the bolt and the nut.

16. The method for adjusting an ion source grid structure according to claim 14, characterized in that, The grid structure further includes a deceleration grid, and the deceleration grid includes a number of third through holes arranged periodically; after installation, the deceleration grid and the screen grid are respectively located on both sides of the acceleration grid, and the first through holes, the second through holes, and the third through holes correspond to each other one by one; the grid pitch adjustment structure further includes a number of second spacer rings with different thickness specifications, and the first fixing device can also fix any one of the second spacer rings between the acceleration grid and the deceleration grid; the grid pitch adjustment method further includes: obtaining a third adjustment point from the middle region of the deceleration grid, the first adjustment point, the second adjustment point, and the third adjustment point are arranged along the first direction, and obtaining the second target distance between the acceleration grid and the deceleration grid; according to the second target distance, select a second spacer ring with a thickness corresponding to the second target distance; fix the second spacer ring between the second adjustment point and the third adjustment point; and fix the selected second spacer ring between the acceleration grid and the deceleration grid through the first fixing device.

17. The adjustment method of the ion source grid structure according to claim 13, wherein, A method for performing at least one structural adjustment on the grid structure according to the etching process requirements includes: obtaining a first process parameter setting when the etching machine reaches optimal uniformity; determining whether the first process parameter setting meets the requirements of a preset process parameter range according to the first process parameter setting; when the first process parameter setting does not meet the requirements of the preset process parameter range, performing the grid pitch adjustment.

18. The adjustment method of the ion source grid structure according to claim 17, wherein, A method for performing at least one structural adjustment on the grid structure according to the etching process requirements further includes: performing local shielding adjustment on the grid structure according to the etching process requirements to shield part of the first through holes or the second through holes.

19. The adjustment method of the ion source grid structure according to claim 18, wherein, A method for performing local shielding adjustment on the grid structure according to the etching process requirements includes: obtaining a second process parameter setting when the etching machine reaches optimal uniformity; determining whether the second process parameter setting meets the requirements of the preset process parameter range according to the second process parameter setting; when the second process parameter setting does not meet the requirements of the preset process parameter range, performing the local shielding adjustment.

20. The adjustment method of the ion source grid structure according to claim 19, wherein, After the local shielding adjustment, it further includes: obtaining a third process parameter setting when the etching machine reaches optimal uniformity; determining whether the third process parameter setting meets the requirements of the preset process parameter range according to the third process parameter setting; when the third process parameter setting does not meet the requirements of the preset process parameter range, continuing the structural adjustment until the second process parameter setting or the third process parameter setting meets the requirements of the preset process parameter range.

21. The adjustment method of the ion source grid structure according to claim 18, wherein, The method for the local shielding adjustment includes: obtaining a target shielding area on the screen grid or the acceleration grid; obtaining a corresponding shielding structure according to the target shielding area, the shielding structure being detachable and fixable to the first through holes or the second through holes of the target shielding area and shielding part of the first through holes or the second through holes; installing the shielding structure on the surface of the screen grid or the acceleration grid of the target shielding area.

22. The adjustment method of the ion source grid structure according to claim 21, wherein, The shielding structure includes a shielding layer and a second fixing device fixedly connected to the shielding layer, the size of the shielding layer being larger than the size of a single first through hole or second through hole; the shielding layer is installed on the surface of the screen grid or the acceleration grid of the target shielding area through the second fixing device.

23. The adjustment method of the ion source grid structure according to claim 22, wherein, The second fixing device includes a plurality of snap-fastener structures, each snap-fastener structure including a female snap perpendicular to the surface of the shielding layer and fixedly connected to the shielding layer, and a male snap cooperating with the female snap; each female snap can pass through the first through hole to install the shielding layer on the surface of the screen grid, or each female snap can pass through the second through hole to install the shielding layer on the surface of the acceleration grid.

24. The adjustment method of the ion source grid structure according to claim 23, wherein, The method for installing the shielding layer on the surface of the screen grid or the acceleration grid of the target shielding area includes: making the male snap and the female snap have an interference fit.

25. The adjustment method of the ion source grid structure according to claim 13, wherein, The machine installation includes edge-fixing the screen grid and the acceleration grid respectively by an edge-fixing method.

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