Endpoint detection apparatus and ion beam etching system

Abstract

An endpoint detection apparatus and an ion beam etching system. The endpoint detection apparatus comprises a mounting bottom plate, an anti-deposition member, a light-transmitting piece, and a detection element. The light-transmitting piece is mounted on the outer side of the mounting bottom plate by means of a fixing member, and the mounting bottom plate is provided with a light-transmitting hole leading to the light-transmitting piece. The anti-deposition member is arranged on the inner side of the mounting bottom plate and extends from the mounting bottom plate in the direction away from the inner side surface of the mounting bottom plate, a light guide channel corresponding to the light-transmitting hole being provided in the anti-deposition member. The detection element is connected to the mounting bottom plate, is located on the outer side of the light-transmitting piece, and corresponds to the light-transmitting piece. The endpoint detection apparatus has an anti-deposition effect, and can effectively prevent particles from being deposited on the light-transmitting piece, thus greatly prolonging the maintenance interval of the light-transmitting piece while not affecting the normal detection function.

Description

End point detection device and ion beam etching system

[0001] This application claims priority to the invention patent application filed with the China Patent Office on November 16, 2022, with application number 202211442526.6 and invention name “An endpoint detection device and ion beam etching system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of semiconductor chip production technology, and in particular to an endpoint detection device used in a chip ion beam etching system. The present invention also relates to an ion beam etching system equipped with the endpoint detection device. Background Art

[0003] With the development of semiconductor devices, wafer pattern precision has become increasingly higher, and a series of dry etching technologies have gradually been developed. The most commonly used ones are plasma etching, reactive ion etching, and ion beam etching. Among them, ion beam etching is a purely physical etching method with no selectivity for materials. It can be used to etch almost any solid material, including metals, alloys, oxides, compounds, hybrid materials, semiconductors, insulators, superconductors, etc.

[0004] When ion beam etching is working, inert gases such as Ar, Kr or Xe need to be filled into the ion source discharge chamber to ionize and form a uniform plasma. The ions are then drawn out and accelerated by the gate in a beam shape. The ion beam with a certain energy enters the reaction chamber and bombards the surface of the wafer on the carrier stage, causing the material atoms to sputter, achieving the etching purpose and then obtaining the etched pattern.

[0005] In ion beam etching systems, excessive etching can damage the next layer of material, while insufficient etching can affect the next process and cause device failure. Therefore, in order to selectively and accurately remove the material in the predetermined area during the etching process, real-time monitoring is required to control the etching process and etching amount.

[0006] Endpoint detection is a commonly used process control method in etching, and methods include optical emission spectroscopy (OES), laser interferometry, and mass spectrometry. Of these, optical emission spectroscopy (OES) can very sensitively detect subtle changes in the film layer, providing a variety of information about the etching process in real time. It is easily integrated with the etching tool without affecting the etching process, making it the most widely used. Its principle is that at the end point of etching, the light intensity of specific product groups drops sharply, while the product groups formed by the reaction between the underlying film and the plasma begin to increase. Endpoint detection is achieved by monitoring the changes in the intensity of the spectral lines emitted by these groups.

[0007] In existing ion beam etching systems, the optical emission spectroscopy (OES) endpoint detection device is often fixed to the chamber and stationary, such as on the top, transfer side, or ion source side. However, due to its distance from the wafer surface, the intensity of the emission lines received by the reactants or products is weak, resulting in poor real-time monitoring. Furthermore, the light-transmitting plate has poor anti-deposition capabilities, requiring maintenance within a short period of time, which fails to meet customer requirements for mean time between maintenance (MTBC).

[0008] Summary of the Invention

[0009] The object of the present invention is to provide an endpoint detection device to solve the above problems.

[0010] Another object of the present invention is to provide an ion beam etching system provided with the endpoint detection device.

[0011] To achieve the above-mentioned purpose, the present invention provides an end point detection device, including a mounting base, an anti-deposition part, a light-transmitting sheet, and a detection element; the light-transmitting sheet is mounted on the outer side of the mounting base through a fixing part, and the mounting base is provided with a light-transmitting hole leading to the light-transmitting sheet; the anti-deposition part is arranged on the inner side of the mounting base, and extends from the mounting base in a direction away from the inner surface of the mounting base, and is provided with a light-guiding channel corresponding to the light-transmitting hole inside the anti-deposition part; the detection element is connected to the mounting base, and is located on the outer side of the light-transmitting sheet and corresponds to the light-transmitting sheet.

[0012] Optionally, the anti-deposition member is provided with a first striped baffle and a second striped baffle at both ends of its light guide channel, respectively. The first striped baffle and the second striped baffle are provided with striped grooves respectively, and the axial projections of the striped grooves of the two are in a cross state.

[0013] Optionally, the stripe-shaped grooves of the first stripe barrier and the second stripe barrier are stripe-shaped grooves with unequal intervals and / or unequal widths.

[0014] Optionally, the anti-deposition member is provided with plugs spaced apart along the axial direction inside the light guide channel thereof, the plugs dividing the light guide channel into a plurality of inner cavities, and a light guide hole is provided at the center of the plug.

[0015] Optionally, the anti-deposition component includes a plug tube; the inner cavity of the plug tube forms the light-guiding channel, the plug tube is provided with a lateral socket, and the plug piece is inserted into the light-guiding channel of the plug tube along the radial direction from the lateral socket.

[0016] Optionally, the plug tube is provided with an outer sleeve, and an annular space is formed between the two; the plug has a first semicircular portion adapted to the inner diameter of the outer sleeve and a second semicircular portion adapted to the inner diameter of the plug tube, and the diameter of the first semicircular portion is larger than the diameter of the second semicircular portion.

[0017] Optionally, the plugs are distributed at unequal intervals, and / or the light guide holes of the plugs at different positions have different apertures.

[0018] Optionally, a fixing frame is connected to the end of the plug tube; the fixing frame is used to fix the relative position of the outer sleeve and the plug tube to hold the plug piece therebetween.

[0019] Optionally, the light-transmitting sheet mounting surface of the mounting base has an angle that deviates from the optical axis.

[0020] Optionally, the aspect ratio of the light-transmitting hole is ≥3, and the depth-to-width ratio of the light-transmitting hole is ≥2.

[0021] Optionally, a cavity for accommodating the light-transmitting sheet is provided on the outer side of the mounting base plate, and the light-transmitting sheet is located inside the cavity and is pressed and fixed by a fixing cover.

[0022] Optionally, a light-transmitting sheet gasket is provided between the fixing cover and the light-transmitting sheet; and / or a sealing ring is provided between the light-transmitting sheet and the bottom of the cavity.

[0023] Optionally, the detection element is mounted on the fixed cover via an adjusting member, and a height adjustment structure is provided between the adjusting member and the fixed cover.

[0024] Optionally, the height adjustment structure includes an adjustment slot provided in the middle of the fixed cover, and the adjustment member can be embedded in the adjustment slot so as to move up and down. Threaded holes are respectively provided at the top and bottom of the fixed cover, and adjustment screws for adjusting the height of the adjustment member are provided in the threaded holes.

[0025] Optionally, the adjustment groove is a rectangular groove, and the adjustment piece is a rectangular block structure; the inner bottom of the adjustment groove is provided with a step portion supporting the adjustment piece, and the two sides of the adjustment piece are limited by the side walls of the adjustment groove, and the adjustment piece has the freedom to move up and down in the adjustment groove.

[0026] Optionally, a threaded hole is provided on a side portion of the adjustment slot, a fastening screw is provided in the threaded hole, and the fastening screw presses the adjustment member through an edge portion of its head.

[0027] Optionally, the fixed cover is provided with scale lines, and the adjusting member is provided with indicator lines.

[0028] To achieve the above-mentioned other object, the present invention provides an ion beam etching system, which is provided with an endpoint detection device, wherein the endpoint detection device is any of the endpoint detection devices described above, and the detection element of the endpoint detection device is connected to the spectrometer via an optical fiber.

[0029] Optionally, the endpoint detection device is installed on the lower electrode rocker arm of the ion beam etching system.

[0030] Optionally, the mounting base plate of the endpoint detection device constitutes a vacuum sealing plate of the lower electrode rocker arm.

[0031] Optionally, the lower electrode rocker arm is fixed to the inner surface of the chamber cover of the etching chamber through a magnetic fluid shaft, and the chamber cover is connected to the cavity body of the etching chamber through a hinge.

[0032] Optionally, the optical fiber is routed along the rotation center of the lower electrode rocker arm.

[0033] The endpoint detection device provided by the present invention disposes a light-transmitting sheet on the outside of a mounting base, thereby positioning the light-transmitting sheet away from the etching environment and preventing excessive exposure of the light-transmitting sheet to the etching environment. Furthermore, an anti-deposition member is provided on the inside of the mounting base, extending away from the inner surface of the mounting base and having a light-guiding channel formed therein. In this way, radicals generated by etching need to travel a longer path to reach the light-transmitting sheet, thereby achieving an anti-deposition effect, effectively preventing particulate matter from depositing on the light-transmitting sheet and significantly improving the maintenance cycle of the light-transmitting sheet. Furthermore, light can pass through the light-guiding channel of the anti-deposition member and the light-transmitting hole of the mounting base to reach the light-transmitting sheet, thereby being detected by the detection element without affecting normal detection functions.

[0034] The ion beam etching system provided by the present invention is provided with the endpoint detection device. Since the endpoint detection device is installed on the lower electrode rocker arm of the ion beam etching system, it is close to the wafer and revolves with the wafer, and can receive stronger emission spectrum lines of reactants or products, thereby effectively improving the monitoring effect of endpoint detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a schematic diagram of the exploded structure of an endpoint detection device provided by an embodiment of the present invention;

[0036] FIG2 is a cross-sectional view of the endpoint detection device shown in FIG1 after assembly;

[0037] FIG3 is a partial enlarged view of the light-transmitting hole of the mounting base shown in FIG1 ;

[0038] FIG4 is a schematic diagram of an end portion of the height adjustment structure shown in FIG1 ;

[0039] FIG5 is a schematic structural diagram of a first stripe baffle and a second stripe baffle;

[0040] FIG6 is a schematic structural diagram of an anti-deposition member provided in another embodiment;

[0041] FIG7 is a curve showing a change in light intensity signal within one MTBC cycle after using the endpoint detection device provided by the present invention;

[0042] FIG8 is a partial schematic diagram of an ion beam etching system provided by an embodiment of the present invention.

[0043] In the figure: 10. Anti-deposition member 12. First striped baffle 13. Second striped baffle 14. Striped groove 15. Plug tube 16. Base 17. Plug 18. Fixing bracket 19. Outer sleeve 20. Mounting base 21. Light transmission hole 22. Light transmission hole width 23. Light transmission hole depth 24. Light transmission plate mounting surface 30. Sealing ring 40. Light transmission plate 41. Light transmission plate gasket 50. Fixing cover 51. Adjusting screw 52. Fastening screw 53. Threaded hole 54. Scale line 55. Indicator line 60. Adjusting member 70. Detection element 80. Optical fiber 90. Spectrometer 110. Cavity 120. Lower electrode assembly 130. Cavity cover 140. Electrostatic chuck 150. Lower electrode rocker arm 160. Magnetic fluid axis 170. Transfer port 210. Wafer center axis 220. Revolution axis DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0045] In this article, terms such as "upper, lower, inside, outside" are established based on the positional relationships shown in the drawings. Depending on the different drawings, the corresponding positional relationships may also change accordingly. Therefore, they cannot be understood as absolute limitations on the scope of protection; moreover, relational terms such as "first" and "second" are only used to distinguish one component from another with the same name, and do not necessarily require or imply any actual relationship or order between these components.

[0046] Please refer to Figures 1, 2, and 3. Figure 1 is a schematic diagram of the decomposed structure of an endpoint detection device provided by an embodiment of the present invention; Figure 2 is a cross-sectional view of the endpoint detection device shown in Figure 1 after assembly; and Figure 3 is a partial enlarged view of the light-transmitting hole of the mounting base shown in Figure 1.

[0047] As shown in the figure, in a specific embodiment, the end point detection device provided by the present invention is mainly composed of an anti-deposition part 10, a mounting base plate 20, a sealing ring 30, a light-transmitting sheet 40, a fixed cover 50, an adjustment part 60, a detection element 70, an optical fiber 80, a spectrometer 90 and other parts.

[0048] The mounting base 20 is generally flange-shaped, with the upper half of the flange edge being semicircular and the lower half being rectangular, so as to match the shape of the mounting position; the light-transmitting sheet 40 is mounted on the outside of the mounting base 20 through the fixing cover 50, and the mounting base 20 is provided with a light-transmitting hole 21 leading to the light-transmitting sheet 40, and the light-transmitting sheet 40 completely covers the light-transmitting hole 21; the anti-deposition component 10 is cylindrical, with a flange at one end, and is mounted on the inner side of the mounting base 20 through the flange, and the anti-deposition component 10 has a certain length, which extends from the mounting base 20 in a direction away from the inner surface of the mounting base, and is provided with a light-guiding channel corresponding to the light-transmitting hole 21 inside.

[0049] The detection element 70 is connected to the mounting base 20 , and is located outside the light-transmitting sheet 40 and facing the center area of ​​the light-transmitting sheet 40 . The detection element 70 is connected to the spectrometer 90 via an optical fiber 80 to transmit the optical signal to the spectrometer 90 .

[0050] In actual use, the outside of the fixed cover 50 , the adjusting member 60 , the detecting element 70 and the mounting base 20 are in the atmospheric environment, and the anti-deposition member 10 , the mounting base 20 and the inside of the mounting base 20 are exposed to the vacuum environment.

[0051] A circular cavity for accommodating the light-transmitting sheet 40 is provided on the outer side of the mounting base 20 . The light-transmitting sheet 40 is located inside the cavity and is pressed and fixed by the fixing cover 50 .

[0052] The light-transmitting sheet 40 serves as a sealing force-bearing member between the vacuum and the atmosphere. In order to prevent damage due to excessive extrusion, a soft light-transmitting sheet gasket 41 is provided between the fixed cover 50 and the light-transmitting sheet 40. The material of the light-transmitting sheet 40 can be quartz or sapphire. Depending on different process requirements, the material of the light-transmitting sheet gasket 41 can be PP (polypropylene) or PTFE (polytetrafluoroethylene).

[0053] A sealing ring 30 is provided between the light-transmitting sheet 40 and the bottom of the cavity. The fixing cover 50 is installed on the mounting base plate 20 to press the light-transmitting sheet 40 , thereby squeezing the sealing ring 30 to achieve sealing.

[0054] The mounting surface of the light-transmitting sheet 40 has an angle that deviates from the optical axis. That is, by changing the design angle of the light-transmitting sheet mounting surface 24 on the mounting base 20, the center of the detection element 70 can be made parallel to the wafer surface, or the center of the detection element 70 can be made at a certain angle to the wafer surface.

[0055] The light-transmitting hole 21 on the mounting base 20 is designed as a narrow and deep slit, and its cross-section is a flat oblong. The aspect ratio of the light-transmitting hole 21 is ≥3, and the depth-to-width ratio of the light-transmitting hole is ≥2, that is, the ratio of the depth 23 to the width 22 shown in the figure is ≥2, so as to achieve the purpose of preventing deposition.

[0056] The endpoint detection device may use optical emission spectroscopy (OES) to implement the endpoint detection function, and relies on the spectrometer 90 to convert the detected optical signal inside the ion beam etching chamber into an analog electrical signal output.

[0057] In order to detect the optical signal, the center of the detection element 70 must be higher than the upper surface of the wafer, and the height difference will directly affect the intensity of the optical signal. Therefore, a structure that is easy to adjust the height is designed between the adjustment member 60 and the fixed cover 50.

[0058] Please also refer to FIG. 4 , which is a schematic diagram of an end portion of the height adjustment structure shown in FIG. 1 .

[0059] As shown in the figure, the detection element 70 is mounted on the fixed cover 50 through the adjustment member 60 , and a height adjustment structure is provided between the adjustment member 60 and the fixed cover 50 .

[0060] Specifically, the adjustment member 60 is a block-shaped structure with a square axial projection. A rectangular adjustment slot is provided in the middle of the fixed cover 50. The lateral width of the rectangular adjustment slot is substantially equal to that of the adjustment member 60, and the longitudinal length of the rectangular adjustment slot is greater than the longitudinal length of the adjustment member 60. The inner bottom of the adjustment slot is provided with a stepped portion to support the adjustment member 60 (i.e., the inner bottom of the adjustment slot has a portion that is not completely penetrated). The adjustment member 60 is restrained on both sides by the side walls of the adjustment slot and cannot move in the left-right direction. The adjustment member 60 has the freedom to move up and down within the adjustment slot. Once inserted into the adjustment slot, the adjustment member 60 can move up and down within the adjustment slot. Threaded holes are provided at the top and bottom of the fixed cover 50, respectively, and adjustment screws 51 are installed in the threaded holes to adjust the height of the adjustment member 60.

[0061] A threaded hole is provided on the side of the adjustment slot, and a fastening screw 52 is provided in the threaded hole. The fastening screw 52 presses the adjustment member 60 through the edge of the head thereof.

[0062] The fixed cover 50 is designed with multiple scale lines 54, spaced symmetrically around the center. The adjustment member 60 is designed with a single indicator line 55, which serves as a pointer for easy visual adjustment. To adjust the height, turn the upper and lower adjustment screws 51, following the indications of the indicator lines 55, to secure the adjustment member 60 in the desired position. Then, tighten the fastening screws 52 to fully secure the adjustment member 60 to the fixed cover 50. Initially, the adjustment member 60 is positioned in the center of the fixed cover 50, with a 2mm adjustment range provided above and below.

[0063] The detection element 70 is provided with an external thread, and a through threaded hole 53 is provided in the middle of the adjustment member 60. The detection element 70 is connected to the adjustment member 60 through a thread. The detection element 70 can be directly screwed into the threaded hole 53 of the adjustment member 60 and can move with the adjustment member 60.

[0064] Please continue to refer to FIG5 , which is a schematic structural diagram of the first stripe blocking piece and the second stripe blocking piece.

[0065] In another embodiment, the anti-deposition member 10 is provided with a first striped baffle 12 and a second striped baffle 13 at both ends of its light guide channel, respectively. The first striped baffle 12 and the second striped baffle 13 are respectively provided with striped grooves 14 of equal spacing and width starting from the center, and the axial projections of the striped grooves 14 of the two are in a cross state. In this embodiment, the axial projections of the striped grooves 14 of the first striped baffle 12 and the second striped baffle 13 are perpendicular to each other, and the baffles of the two are in a 90° cross state.

[0066] Of course, in other embodiments, the stripe-shaped grooves 14 on the first stripe barrier 12 and the second stripe barrier 13 may also have unequal intervals and / or unequal widths.

[0067] By adding a first striped baffle 12 and a second striped baffle 13 at both ends of the anti-deposition component 10, the reactants or products must pass through the striped groove 14 before reaching the transparent sheet 40, and are preferentially deposited on the baffles forming the striped groove 14, thereby reducing the amount of deposition on the transparent sheet 40 and further improving the anti-deposition effect.

[0068] Please refer to FIG. 6 , which is a schematic structural diagram of an anti-deposition component provided by another embodiment.

[0069] In another embodiment, the anti-deposition member 10 is provided with plugs 17 spaced apart in the axial direction inside its light guide channel. These plugs 17 divide the light guide channel of the anti-deposition member 10 into several spaced inner cavities. A coaxial light guide hole is provided in the center of the plug 17.

[0070] Specifically, the main body of the anti-deposition member 10 is a plug tube 15 , the inner cavity of the plug tube 15 forms a light guide channel, the plug tube 15 is provided with a lateral insertion port, and the plug piece 17 is inserted into the light guide channel of the plug tube 15 along the radial direction from the lateral insertion port.

[0071] An outer sleeve 19 is sleeved on the outside of the plug tube 15, forming an annular space between the two. The plug 17 has a first semicircular portion that is adapted to the inner diameter of the outer sleeve 19 and a second semicircular portion that is adapted to the inner diameter of the plug tube 15. The diameter of the first semicircular portion is larger than the diameter of the second semicircular portion. The plug 17 divides the light guide channel into several inner cavities through the second semicircular portion and a part of the first semicircular portion. The remaining annular portion of the first semicircular portion is located in the annular space between the plug tube 15 and the outer sleeve 19.

[0072] The spacings between the plugs 17 may be different, and the apertures of the light guide holes of the plugs 17 at different positions may also be different.

[0073] One end of the plug tube 15 is provided with a base 16 and the other end is connected to a fixing frame 18. The fixing frame 18 is disc-shaped and is fixed to the end of the plug tube 15 by screws, thereby pressing the outer sleeve 19 onto the base 16, so that the position of the outer sleeve 19 and the plug tube 15 is relatively fixed, and multiple plug pieces 17 are positioned at the same time.

[0074] By arranging a plug 17 in the light-guiding channel of the anti-deposition component 10, the reactants or products must first pass through the various inner cavities formed by the plug 17 before reaching the light-transmitting sheet 40, and are preferentially deposited in the various inner cavities, thereby reducing the amount of deposition on the light-transmitting sheet 40, effectively avoiding the deposition of particulate matter on the light-transmitting sheet 40, and further improving the anti-deposition effect.

[0075] The above four anti-deposition structures (light-transmitting hole, light-guiding channel, striped baffle and plugging plate) can be used alone or in combination of two or more to prevent particles from being deposited on the light-transmitting sheet 40 .

[0076] The endpoint detection device is designed with an anti-deposition structure, which can effectively prevent particulate matter from depositing on the transparent sheet 40. Relevant experiments have shown that after using the above-mentioned endpoint detection device, the light intensity signal does not significantly weaken within one MTBC cycle (see Figure 7), which greatly improves the maintenance cycle of the transparent sheet 40.

[0077] In addition, the endpoint detection device is easy to install and adjust, and has good practical use effect.

[0078] The above embodiments are merely preferred solutions of the present invention and are not intended to be limiting. Based on these solutions, targeted adjustments can be made based on actual needs to achieve various implementations. For example, the mounting surface of the anti-deposition member 10 can be provided with an inner cavity, thereby forming a vacuum cavity with a diameter larger than that of the light guide channel thereof, together with the mounting base plate 20. Alternatively, the mounting base plate 20 can be designed into other shapes, and so on. Due to the numerous possible implementations, we will not provide a detailed list of examples here.

[0079] As shown in FIG8 , in addition to the above-mentioned endpoint detection device, the present invention also provides an ion beam etching system, which is provided with an endpoint detection device, and the endpoint detection device is the endpoint detection device described above, and the detection element 70 of the endpoint detection device is connected to the spectrometer 90 via an optical fiber 80 .

[0080] Specifically, the endpoint detection device is mounted on and integrated with the lower electrode rocker arm 150 of the ion beam etching system. Its mounting base 20 serves as a vacuum seal for the lower electrode rocker arm 150. This allows the detection element 70 to be located less than 300 mm from the wafer's central axis 210, away from the transfer port 170, and able to orbit with the wafer, but not rotate with it.

[0081] The lower electrode rocker arm 150 is fixed to the inner surface of the chamber cover 130 of the etching chamber through the magnetic fluid shaft 160. The chamber cover 130 is connected to the chamber body 110 of the etching chamber through a hinge. It can be opened along with the chamber cover 130, which is easy to install and has a large maintenance space.

[0082] During use, the wafer is adsorbed on the lower electrode assembly 120 through the electrostatic suction cup 140, and rotates around the wafer center axis 210. The lower electrode assembly 120 and the lower electrode rocker arm 150 are fixed together, and together with the wafer, they rotate around the orbital rotation axis 220.

[0083] The optical fiber 80 is routed at the rotation center of the lower electrode rocker arm 150 and is designed with a fixing part so that it does not follow the revolution, so as to achieve the purpose of protecting the optical fiber and increasing its service life.

[0084] Since the endpoint detection device is installed on the lower electrode rocker arm 150 in the ion beam etching system, it is close to the wafer and revolves with the wafer, so it can receive stronger emission lines of reactants or products, thereby effectively improving the monitoring effect of endpoint detection.

[0085] For the rest of the structure of the ion beam etching system, please refer to the prior art and will not be described in detail in this article.

[0086] The endpoint detection device and ion beam etching system provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An endpoint detection device, characterized in that: The invention comprises a mounting base plate (20), an anti-deposition member (10), a light-transmitting sheet (40), and a detection element (70); the light-transmitting sheet (40) is mounted on the outer side of the mounting base plate (20) through a fixing member, and the mounting base plate (20) is provided with a light-transmitting hole (21) leading to the light-transmitting sheet (40); the anti-deposition member (10) is arranged on the inner side of the mounting base plate (20) and extends from the mounting base plate (20) in a direction away from the inner surface of the mounting base plate, and is provided with a light-guiding channel corresponding to the light-transmitting hole (21) inside the anti-deposition member (10); the detection element (70) is connected to the mounting base plate (20), and is located on the outer side of the light-transmitting sheet (40) and corresponds to the light-transmitting sheet (40).

2. The endpoint detection device according to claim 1, characterized in that: The anti-deposition member (10) is provided with a first striped baffle (12) and a second striped baffle (13) at both ends of its light guide channel, respectively; the first striped baffle (12) and the second striped baffle (13) are respectively provided with striped grooves (14), and the axial projections of the striped grooves (14) of the two are in a cross state.

3. The endpoint detection device according to claim 2, wherein: The stripe-shaped grooves (14) of the first stripe baffle (12) and the second stripe baffle (13) are stripe-shaped grooves with unequal spacing and / or unequal width.

4. The endpoint detection device according to claim 1, wherein: The anti-deposition member (10) is provided with plugs (17) spaced apart in the axial direction inside its light guide channel. The plugs (17) divide the light guide channel into a plurality of inner cavities. A light guide hole is provided at the center of the plug (17).

5. The endpoint detection device according to claim 4, characterized in that: The anti-deposition component (10) comprises a plug tube (15); the inner cavity of the plug tube (15) forms the light guide channel, the plug tube (15) is provided with a lateral insertion port, and the plug sheet (17) is inserted into the light guide channel of the plug tube (15) along a radial direction from the lateral insertion port.

6. The endpoint detection device according to claim 5, characterized in that: The plug tube (15) is provided with an outer sleeve (19), and an annular space is formed between the two; the plug piece (17) has a first semicircular portion adapted to the inner diameter of the outer sleeve (19) and a second semicircular portion adapted to the inner diameter of the plug tube (15), and the diameter of the first semicircular portion is larger than the diameter of the second semicircular portion.

7. The endpoint detection device according to claim 6, characterized in that: The plugs (17) are distributed at unequal intervals, and / or the light guide holes of the plugs (17) at different positions have different apertures.

8. The endpoint detection device according to claim 7, characterized in that: The end of the plug tube (15) is connected to a fixing frame (18); the fixing frame (18) is used to fix the relative position of the outer sleeve (19) and the plug tube (15) to keep the plug piece (17) therebetween.

9. The endpoint detection device according to any one of claims 1 to 8, characterized in that: The light-transmitting sheet mounting surface (24) of the mounting base plate (20) has an angle that deviates from the optical axis.

10. The endpoint detection device according to any one of claims 1 to 8, characterized in that: The aspect ratio of the light-transmitting hole (21) is ≥3, and the depth-to-width ratio of the light-transmitting hole (21) is ≥2.

11. The endpoint detection device according to any one of claims 1 to 8, characterized in that: A cavity for accommodating the light-transmitting sheet (40) is provided on the outside of the installation base plate (20); the light-transmitting sheet (40) is located inside the cavity and is pressed and fixed by a fixing cover (50).

12. The endpoint detection device according to claim 11, characterized in that: A light-transmitting sheet gasket (41) is provided between the fixed cover (50) and the light-transmitting sheet (40); and / or a sealing ring (30) is provided between the light-transmitting sheet (40) and the bottom of the cavity.

13. The endpoint detection device according to claim 12, characterized in that: The detection element (70) is mounted on the fixed cover (50) via an adjusting member (60), and a height adjustment structure is provided between the adjusting member (60) and the fixed cover (50).

14. The endpoint detection device according to claim 13, wherein: The height adjustment structure comprises an adjustment slot provided in the middle of the fixed cover (50), the adjustment member (60) being embedded in the adjustment slot so as to be movable up and down, and threaded holes being provided at the top and bottom of the fixed cover (50), respectively, and adjustment screws (51) for adjusting the height of the adjustment member being provided in the threaded holes.

15. The endpoint detection device according to claim 14, characterized in that: The adjusting groove is a rectangular groove, and the adjusting member (60) is in a rectangular block structure; a step portion for supporting the adjusting member (60) is provided at the inner bottom of the adjusting groove, and both sides of the adjusting member (60) are limited by the side walls of the adjusting groove, and the adjusting member (60) has the freedom to move up and down in the adjusting groove.

16. The endpoint detection device according to claim 15, characterized in that: A threaded hole is provided on the side of the adjustment slot, a fastening screw (52) is provided in the threaded hole, and the fastening screw (52) presses the adjustment member (60) through the edge of its head.

17. The endpoint detection device according to claim 13, characterized in that: The fixed cover (50) is provided with a scale line (54), and the adjusting member (60) is provided with an indicator line (55).

18. An ion beam etching system, provided with an endpoint detection device, characterized in that: The endpoint detection device is the endpoint detection device according to any one of claims 1 to 17, wherein the detection element (70) of the endpoint detection device is connected to the spectrometer (90) via an optical fiber (80).

19. The ion beam etching system according to claim 18, wherein: The endpoint detection device is installed on the lower electrode rocker arm (150) of the ion beam etching system.

20. The ion beam etching system according to claim 19, wherein: The mounting base plate (20) of the endpoint detection device forms a vacuum sealing plate of the lower electrode rocker arm (150).

21. The ion beam etching system according to claim 19, wherein: The lower electrode rocker arm (150) is fixed to the inner side of a chamber cover (130) of the etching chamber via a magnetic fluid shaft (160), and the chamber cover (130) is connected to the chamber body (110) of the etching chamber via a hinge.

22. The ion beam etching system according to claim 19, 20 or 21, wherein: The optical fiber (80) is routed along the rotation center of the lower electrode rocker arm (150).

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