Electron beam generator and ion beam etching device

Abstract

An electron beam generator (100) and an ion beam etching device. The electron beam generator (100) comprises: an electron beam generation chamber (1), provided with an extraction port (101); and a shielding assembly (2), movably arranged outside the electron beam generation chamber (1). The shielding assembly (2) is configured to shield the extraction port (101), and the extraction area of the extraction port (101) can be adjusted by adjusting the position of the shielding assembly (2). On the basis of the magnitude of the plasma density amplitude inside the electron beam generation chamber (1), the extraction area of the extraction outlet (101) can be adjusted by means of the shielding assembly (2), such that the extraction area can adapt to the change of plasma sheath morphology, and the electron extraction efficiency is always maintained at a high level, thereby effectively improving the performance and stability of the electron beam generator (100).

Description

Electron beam generator and ion beam etching equipment Technical Field

[0001] The present application relates to the field of semiconductor manufacturing, and in particular to an electron beam generator and an ion beam etching device. Background Art

[0002] With the development of micro-nano processing technology, the requirements for etching technology are becoming increasingly higher. Currently, etching can be divided into wet etching and dry etching in principle. Most dry etching uses the principle of radio frequency coupling to generate a plasma source, including inductively coupled plasma (ICP) and capacitively coupled plasma (CCP), and then uses ions or free radicals in the plasma source to perform the required etching process. Compared with wet etching, dry etching has high etching precision, high controllability, and good anisotropy, and is therefore attracting more and more attention.

[0003] For dry etching systems, in addition to ion sources, electron sources also play an important role. For example, for high vacuum (for example: pressure less than 10 -5 In RF etching systems (less than 100 Torr), successful ignition becomes a challenge that affects system stability due to the scarcity of seed electrons. One way to improve RF system ignition stability is to increase the number of seed electrons. Furthermore, in ion beam etching systems, sufficient electron beam current is required to neutralize the extracted ion beam before the etching process to reduce repulsion between ions, improve ion beam uniformity, minimize charge accumulation on the wafer surface, and increase etching rate. Both of these aspects require a high-density, stable electron beam output.

[0004] An electron beam generator that generates an electron beam includes, for example, an ICP electron beam generator, which is a high-performance electron beam generating device. Compared with other types of electron beam generators, the ICP electron beam generator has a wide range of applicable process scenarios and a long life. Therefore, it has received increasing attention in recent years. The working principle of the ICP electron beam generator is as follows: plasma is generated by inductive coupling. Among them, under the action of the spatial electric field, positive ions move toward the ion collector (cathode) with a negative potential, and electrons are extracted from the extraction port. The balance of these two processes maintains the stability of the operation of the ICP electron beam generator.

[0005] However, the electron beam generator in the prior art has problems with low electron extraction performance and efficiency. Summary of the Invention

[0006] The present application aims to solve at least one of the technical problems existing in the prior art, and proposes an electron beam generator and an ion beam etching device, which can solve the problems of low electron extraction performance and efficiency of the electron beam generator in the prior art.

[0007] To achieve the purpose of this application, an electron beam generator is provided, comprising:

[0008] An electron beam generating cavity having an outlet;

[0009] A shielding component is movably arranged outside the electron beam generating cavity; the shielding component is configured to shield the lead-out port, and the lead-out area of ​​the lead-out port can be adjusted by adjusting the position of the shielding component.

[0010] In some embodiments, the shielding assembly includes a plurality of shielding plates arranged in sequence in the circumferential direction, the inner circumferential surfaces of the plurality of shielding plates together form an outlet control port, and the outlet control port is provided correspondingly to the outlet port;

[0011] The plurality of shielding plates are all capable of moving in the radial direction of the outlet control port, and enclose the outlet control port with different opening areas at different positions in the radial direction of the outlet control port.

[0012] In some embodiments, the outlet control port is coaxial with the outlet port.

[0013] In some embodiments, the electron beam generator further includes a mounting member, the mounting member is provided with a guide groove, the baffle is correspondingly arranged in the guide groove, and each guide groove is used to enable the corresponding baffle to move radially along the lead-out control port.

[0014] In some embodiments, the mounting member is further formed with a hollow portion communicating with the guide groove, and the hollow portion at least partially overlaps with an orthographic projection of the outlet on a radial cross section of the outlet;

[0015] The shielding plate can extend into the hollow portion along the radial direction of the outlet control port.

[0016] In some embodiments, the mounting member is an annular mounting member, and the annular hole of the annular mounting member is coaxially arranged with the outlet;

[0017] Each guide groove is formed with an opening on the inner circumference of the annular mounting member; each shielding plate can extend into the annular hole through the opening along the radial direction of the lead-out control port, and the inner circumference of each shielding plate and the opening are both facing the annular hole.

[0018] In some embodiments, the portion of each shielding plate extending into the hollow portion overlaps with the orthographic projection of the portions of two adjacent shielding plates extending into the hollow portion on the radial cross section of the outlet.

[0019] In some embodiments, the overlapping portions of each shielding plate and the two adjacent shielding plates are located on different sides of the two adjacent shielding plates.

[0020] In some embodiments, a moving channel is formed on the side of each guide groove opposite to the hollow portion and passes through the radial direction of the lead-out control port to the outer side of the mounting member away from the side.

[0021] The electron beam generator also includes multiple connecting rods and multiple linear drive sources, each of the connecting rods is correspondingly arranged in each of the moving channels, and one end of each of the connecting rods is correspondingly connected to each of the baffles, and the other end is correspondingly connected to each of the linear drive sources; each of the linear drive sources is used to drive the corresponding baffle to move radially along the lead-out control port through the corresponding connecting rod.

[0022] In some embodiments, the electron beam generator further includes an annular fixing member, which is fixedly connected to the annular mounting member and is used to confine each of the shielding plates in the corresponding guide groove.

[0023] In some embodiments, a positioning structure is provided between the annular fixing member and the annular mounting member for defining the relative position of the annular fixing member and the annular mounting member.

[0024] In some embodiments, the positioning structure includes a protruding structure formed on the surface of the annular mounting member where the guide groove is located. The protruding structure constitutes a positioning groove on the annular mounting member for limiting the relative position of the annular fixing member on the annular mounting member.

[0025] In some embodiments, the protrusion structure includes an annular protrusion arranged along the outer peripheral edge of the surface of the annular mounting member where the guide groove is located, and a protrusion arranged on the inner peripheral edge of the surface of the annular mounting member where the guide groove is located, and located between each adjacent two guide grooves, the inner peripheral surface of the annular protrusion cooperates with the outer peripheral surface of the annular fixing member; the surface of the protrusion relative to the annular protrusion cooperates with the inner peripheral surface of the annular fixing member.

[0026] In some embodiments, the electron beam generator further comprises a plurality of limiting rods;

[0027] A plurality of limiting channels are formed on the surface of the annular fixing member facing the annular mounting member, each of the limiting channels extending radially along the outlet control port, and a channel opening is formed on the inner circumferential surface of the annular fixing member; each limiting rod is correspondingly disposed in each limiting channel and is capable of extending into the annular hole of the annular fixing member through the channel opening along the radial direction of the outlet control port;

[0028] The limiting rods are stacked one by one on the surface of each shielding plate adjacent to the annular fixing member, and one end of each limiting rod facing the channel opening is fixedly connected to the inner peripheral edge of the corresponding shielding plate.

[0029] In some embodiments, each of the limiting rods is provided with a bent portion on one end facing the channel opening and bent in a direction close to the shielding plate; each of the shielding plates is formed with a fixing hole at an inner peripheral edge of a surface adjacent to the annular fixing member;

[0030] The bent portion of each limiting rod is arranged in the fixing hole of each corresponding shielding plate.

[0031] As another technical solution, the present application also provides an ion beam etching device, comprising a process chamber, and an ion source generating device and a carrying device arranged relative to the process chamber in a first direction, and also comprising the above-mentioned electron beam generator provided in the present application, wherein the electron beam generator is arranged on the cavity body of the process chamber, and the outlet is connected to the process chamber and faces a second direction for drawing an electron beam into the process chamber, wherein the second direction is at an angle to the first direction.

[0032] In some embodiments, a sensor and a controller are further included, wherein the sensor is used to obtain the plasma density in the electron beam generating cavity, and the controller is used to control the shielding component in the electron beam generator to adjust the extraction area of ​​the extraction port according to the plasma density obtained by the sensor.

[0033] This application has the following beneficial effects:

[0034] The electron beam generator provided by the present application can adjust the extraction area of ​​the extraction port of the electron beam generating cavity by blocking the component. Since the extraction performance and efficiency of the electron beam are closely related to the plasma sheath morphology on the surface of the extraction port, and the plasma sheath morphology on the surface of the extraction port is closely related to the plasma density generated inside the electron beam generating cavity, based on this, since the extraction area of ​​the extraction port is fixed in the related art, it can only adapt to one working condition of the electron beam generator, that is, a certain plasma density inside the electron beam generating cavity and the plasma sheath morphology on the corresponding extraction port surface. When the working condition remains unchanged, the extraction area of ​​the extraction port can achieve optimal extraction performance and efficiency. However, when the working condition changes, that is, the plasma density inside the electron beam generating cavity changes, the plasma sheath morphology also changes. At this time, the fixed extraction area cannot adapt to the change in the plasma sheath morphology, thereby making it impossible to maintain the electron extraction efficiency at a relatively large value. In this regard, the solution of the present application controls the shielding component to adjust the lead-out area of ​​the lead-out port according to the magnitude of the plasma density amplitude inside the electron beam generating cavity during the movement of electrons, so that the lead-out area can adapt to the changes in the plasma sheath morphology, so that the electron extraction efficiency is always maintained at a relatively large value, thereby effectively improving the performance and stability of the electron beam generator.

[0035] The ion beam etching equipment provided in the present application, by adopting the above-mentioned electron beam generator provided in the present application, can always maintain the electron extraction efficiency at a relatively large value, thereby optimizing the process effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG1 is a cross-sectional view of an electron beam generator provided in an embodiment of the present application;

[0037] FIG2 is a diagram showing the positional relationship between a shielding component and an electron beam generating cavity used in an embodiment of the present application;

[0038] FIG3A is a three-dimensional structural diagram of another shielding assembly used in an embodiment of the present application at one viewing angle;

[0039] FIG3B is a three-dimensional structural diagram of another shielding assembly used in an embodiment of the present application from another perspective;

[0040] FIG4 is a perspective cross-sectional view of another shielding assembly used in an embodiment of the present application;

[0041] FIG5A is a perspective cross-sectional view of an annular mounting member used in an embodiment of the present application at one viewing angle;

[0042] FIG5B is a perspective cross-sectional view of the annular mounting member used in an embodiment of the present application at another viewing angle;

[0043] FIG6 is an exploded view of the annular mounting member and the shielding assembly used in an embodiment of the present application;

[0044] FIG7 is a perspective view of an annular fixing member used in an embodiment of the present application;

[0045] FIG8 is a diagram showing the structure and distribution of the limiting rods used in an embodiment of the present application;

[0046] FIG9 is an exploded view of the annular mounting member, the shielding assembly, and the annular fixing member used in an embodiment of the present application;

[0047] FIG10 is an assembly diagram of the annular mounting member, the shielding assembly, and the annular fixing member used in an embodiment of the present application;

[0048] FIG11 is a schematic structural diagram of an ion beam etching device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to enable those skilled in the art to better understand the technical solution of the present application, the electron beam generator and ion beam etching equipment provided by the present application are described in detail below with reference to the accompanying drawings.

[0050] Referring to FIG1 , an embodiment of the present application provides an electron beam generator 100, comprising an electron beam generating cavity 1 having an extraction port 101. In some embodiments, the electron beam generator 100 further comprises an extraction electrode 6, a shielding cavity 3, a radio frequency coil 4, and an ion collecting electrode 5, wherein the electron beam generating cavity 1 has the above-mentioned extraction port 101, and electrons in the electron beam generating cavity 1 can move from the extraction port 101 to the outside of the electron beam generating cavity 1. The extraction port 101 can specifically be a through hole provided in a cavity wall (e.g., a lower cavity wall) of the electron beam generating cavity 1. The through hole can be a straight through hole or a variable diameter hole, such as a tapered hole, the diameter of which increases along the direction of electron movement.

[0051] The extraction electrode 6 is arranged outside the electron beam generating cavity 1 and is located at intervals on the side where the extraction port 101 is located. The extraction electrode 6 has a first extraction port 61, which is arranged corresponding to the extraction port 101. The first extraction port 61 is greater than or equal to the extraction port 101 and is used to guide the movement of electrons. The above-mentioned electron beam generating cavity 1 is arranged inside the shielding cavity 3, and can be specifically fixed to the upper cavity wall of the shielding cavity 3 by fasteners 11. The shielding cavity 3 is used to shield the electric field in the electron beam generating cavity 1 to avoid interference with external parts. A second extraction port 33 for allowing electrons to pass through is provided on the cavity wall of the shielding cavity 3 adjacent to the extraction port 101. The second extraction port 33 is arranged corresponding to the extraction port 101 (for example, coaxially arranged), and the second extraction port 33 is greater than or equal to the extraction port 101 to avoid affecting the movement of electrons. Specifically, the shielding cavity 3 includes a shielding cavity body 31 with one end open and a shielding cavity cover 32 sealedly connected to the shielding cavity body 31. The shielding cavity cover 32 is superimposed on the outer surface of the cavity wall where the second outlet 33 of the electron beam generating cavity 1 is located, and is used to seal the open end of the shielding cavity body 31. The above-mentioned second outlet 33 is, for example, a through hole arranged in the shielding cavity cover 32.

[0052] An annular space 34 is defined circumferentially between the inner surface of the shielding cavity 3 and the outer surface of the electron beam generating cavity 1. This annular space 34 is formed, for example, by the inner circumferential surface of the shielding cavity body 31, the outer circumferential surface of the electron beam generating cavity 1, the inner surface of the upper cavity wall of the shielding cavity body 31, and the inner surface of the shielding cavity cover 32. A radio frequency coil 4 is disposed in this annular space 34 and surrounds the electron beam generating cavity 1. The radio frequency coil 4 is electrically connected to an radio frequency source, which may include, for example, an radio frequency power supply and an impedance matcher. The radio frequency power supply is electrically connected to the radio frequency coil 4 via the impedance matcher to apply radio frequency power to the radio frequency coil 4 to excite the gas (e.g., an inert gas) within the electron beam generating cavity 1 to form a plasma.

[0053] One end of the ion collector 5 extends from the side of the shielding cavity 3 away from the second outlet 33 (e.g., the upper side of the shielding cavity 3) through the shielding cavity 3 and the electron beam generating cavity 1 in sequence, and extends into the interior of the electron beam generating cavity 1. The ion collector 5 is provided with an air inlet channel for connecting to a gas source, and an air inlet 51 of the air inlet channel is connected to the interior of the electron beam generating cavity 1 for introducing gas (e.g., an inert gas) into the interior of the electron beam generating cavity 1. In some embodiments, the ion collector 5 is tubular, and the interior space of the tube is the air inlet channel. There are multiple air inlets 51, which are evenly distributed circumferentially in the tube wall. The air inlets 51 are, for example, through holes that radially penetrate the tube wall.

[0054] When the electron beam generator 100 is working, an inert gas is introduced into the electron beam generating cavity 1 through the ion collecting electrode 5, and the radio frequency source is turned on to load radio frequency power to the radio frequency coil 4 to excite the inert gas inside the electron beam generating cavity 1 to form a plasma. The ion collecting electrode 5 has a positive potential and the extraction electrode 6 has a negative potential, and a spatial electric field is formed between the two. The positive ions in the plasma move toward the ion collecting electrode 5 with a negative potential, while the electrons in the plasma move toward the extraction electrode 6 with a positive potential and move from the extraction port 101 to the outside of the electron beam generating cavity 1.

[0055] The inventors discovered that the extraction performance and efficiency of the electron beam are closely related to the morphology of the plasma sheath on the surface of the extraction port 101, and the morphology of the plasma sheath on the surface of the extraction port 101 is closely related to the plasma density generated inside the electron beam generating cavity 1. Based on this, since the extraction area of ​​the extraction port 101 in the related art is fixed, it can only adapt to one working condition of the electron beam generator, that is, a certain plasma density inside the electron beam generating cavity and the corresponding plasma sheath morphology on the surface of the extraction port 101. When the working condition remains unchanged, the above-mentioned fixed extraction area of ​​the extraction port 101 can achieve the optimal extraction performance and efficiency. In other words, the extraction area of ​​the extraction port 101 can only be the optimal size that maintains the electron extraction efficiency at a relatively large value under a certain working condition. However, when the working condition changes, that is, the plasma density inside the electron beam generating cavity changes, the plasma sheath morphology also changes accordingly. At this time, the fixed extraction area cannot adapt to the change in the plasma sheath morphology, and thus cannot always maintain the electron extraction efficiency at a relatively large value, resulting in a decrease in the extraction performance and efficiency of the electron beam.

[0056] To address the above-mentioned issues, the electron beam generator provided in an embodiment of the present application further includes a shielding assembly 2, which is used to adjust the extraction area of ​​the extraction port 101. Specifically, the shielding assembly 2 is, for example, disposed outside the electron beam generating cavity 1 and located on one side of the extraction port 101, for example, between the electron beam generating cavity 1 and the extraction electrode 6. In the case where a shielding cavity 3 is provided, as shown in FIG1 , the shielding assembly 2 can also be disposed between the shielding cavity 3 and the extraction electrode 6.

[0057] The shielding assembly 2 is used to adjust the extraction area of ​​the extraction port 101. The extraction area of ​​the extraction port 101 refers to the radial cross-sectional area of ​​the opening through which electrons can pass. During electron movement, the electron beam generator 100 adjusts the extraction area of ​​the extraction port 101 according to the plasma density amplitude within the electron beam generating cavity 1. This allows the extraction area to adapt to changes in the plasma sheath morphology, maintaining a high electron extraction efficiency, thereby effectively improving the performance and stability of the electron beam generator.

[0058] There are many ways for the shielding component 2 to adjust the lead-out area of ​​the lead-out port 101. For example, as shown in FIG2 , the shielding component 2 can be movably disposed outside the electron beam generating cavity 1, for example, disposed on the side of the lead-out port 101 outside the electron beam generating cavity 1. The shielding component 2 is configured to shield the lead-out port 101, and the lead-out area of ​​the lead-out port 101 can be adjusted by adjusting the position of the shielding component 2. In other words, by adjusting the position of the shielding component 2, the area of ​​the lead-out port 101 shielded by the shielding component 2 can be adjusted to achieve the adjustment of the lead-out area of ​​the lead-out port 101, that is, the shielding component 2 can be adjusted to shield a partial area A of the lead-out port 101, and the opening area of ​​the unshielded area B of the lead-out port 101 is the lead-out area of ​​the lead-out port 101. It is easy to understand that the opening area of ​​the outlet 101 itself is fixed, and as the position of the shielding assembly 2 changes, the area of ​​the partially blocked area A of the outlet 101 changes accordingly, and the area of ​​the unblocked area B of the outlet 101 also changes accordingly. The area of ​​this area B is the outlet area of ​​the outlet 101. The shielding assembly 2 can move in various ways, such as translating and / or rotating in a plane parallel to the radial direction of the outlet 101, and this embodiment of the present application does not specifically limit this.

[0059] The shielding assembly 2 shown in FIG2 does not have an opening itself, and relies on its own structure to block part of the area of ​​the outlet 101 to adjust the outlet area of ​​the outlet 101. However, the embodiments of the present application are not limited to this. In other embodiments, for example, as shown in FIG1 , the shielding assembly 2 may also have an outlet control port 201 itself, and the outlet control port 201 is set corresponding to the outlet 101; the shielding assembly 2 is configured to be able to adjust the opening area of ​​the outlet control port 201, that is, to adjust the area of ​​the area corresponding to the outlet 101 and the outlet control port 201 (that is, area C in FIG1 ), thereby adjusting the outlet area of ​​the outlet 101. It is easy to understand that the shielding assembly 2 can block other areas of the outlet 101 except area C in FIG1 .

[0060] The shielding assembly 2 that realizes the above-mentioned function can have a variety of structures. For example, as shown in Figures 3A and 3B, the shielding assembly 2 includes a plurality of shielding plates 21 arranged in sequence in the circumferential direction, and the inner circumferential surfaces 21a of the plurality of shielding plates 21 enclose the extraction control port 201; in some embodiments, the extraction control port 201 is coaxial with the extraction port 101, which is conducive to improving the extraction performance and efficiency of the electron beam. The plurality of shielding plates 21 are all able to move along the radial direction of the extraction control port 201 (i.e., the direction of the arrow in Figure 3A), and enclose the extraction control ports 201 with different opening areas at different positions on the radial direction of the extraction control port 201. In some embodiments, the inner circumferential surfaces 21a of the plurality of shielding plates 21 are all arc surfaces, and enclose the circular extraction control port 201. Of course, in actual applications, according to different needs, the inner circumferential surfaces 21a of the plurality of shielding plates 21 can also be planes or surfaces of other shapes to enclose extraction control ports 201 of different shapes.

[0061] Specifically, the shielding plate 21 is, for example, a flat plate having four side surfaces, one of which is the inner circumferential surface 21a, such as a circular arc surface, and the remaining three side surfaces are flat surfaces. The flat surface opposite the inner circumferential surface is the outer circumferential surface 21b, which is perpendicular to the other two flat surfaces 21c. The other two flat surfaces 21c are parallel to the direction of movement of the shielding plate 21 (i.e., parallel to the radial direction of the outlet control port 201). When the plurality of shielding plates 21 are at their maximum opening position, the opening area of ​​the outlet control port 201 formed by the inner circumferential surfaces 21a of the plurality of shielding plates 21 is maximized. At this time, the plurality of shielding plates 21 may not overlap in the thickness direction (parallel to the axial direction of the outlet control port 201). As the plurality of shielding plates 21 move from the maximum opening position along the radial direction of the outlet control port 201 toward the center of the outlet control port 201, the plurality of shielding plates 21 partially overlap in the thickness direction, thereby reducing the opening area of ​​the outlet control port 201. Furthermore, in some embodiments, the portion where each shielding plate 21 overlaps with two adjacent shielding plates 21 is located on different sides of the two adjacent shielding plates 21. Specifically, as shown in FIG4 , for each of three adjacent shielding plates 21, namely the first shielding plate 21A, the second shielding plate 21B, and the third shielding plate 21C, the second shielding plate 21B is located between the first shielding plate 21A and the third shielding plate 21C. The portion where the first shielding plate 21A overlaps with the second shielding plate 21B (i.e., the portion within the dashed box D1 in FIG4 ) is located on the side of the second shielding plate 21B closer to the outlet 101, and the portion where the third shielding plate 21C overlaps with the second shielding plate 21B (i.e., the portion within the dashed box D2 in FIG4 ) is located on the side of the second shielding plate 21B farther from the outlet 101. In this way, motion interference between the first shielding plate 21A and the third shielding plate 21C due to being located on the same side of the second shielding plate 21B can be avoided.

[0062] In some embodiments, considering the damage resistance of the shielding plate 21 , the thickness of the shielding plate 21 is greater than or equal to 0.5 mm.

[0063] In some embodiments, the electron beam generator further includes a mounting member having guide grooves, in which the shielding plates 21 are correspondingly disposed, and each guide groove is configured to enable the corresponding shielding plate 21 to move radially relative to the lead-out control port 201. The guide grooves can guide the shielding plates 21, enabling the shielding plates 21 to move radially relative to the lead-out control port 201.

[0064] Furthermore, in some embodiments, the mounting member further comprises a hollow portion connected to the guide groove, wherein the hollow portion at least partially overlaps with the orthographic projection of the outlet 101 on a radial cross-section of the outlet 101; the shielding plate 21 is capable of extending into the hollow portion in a radial direction of the outlet control port 201. Specifically, when each shielding plate 21 is fully retracted into its corresponding guide groove, the opening area of ​​the outlet control port 201 is the opening area of ​​the overlapping region of the hollow portion and the outlet 101. When each shielding plate 21 extends into the hollow portion in a radial direction of the outlet control port 201, the multiple shielding plates 21 shield the edge area of ​​the hollow portion, and the inner circumference of the multiple shielding plates 21 encloses the outlet control port 201 in the hollow portion. At this time, the opening area of ​​the outlet control port 201 is the area of ​​the hollow portion that is not blocked by the multiple shielding plates 21.

[0065] The mounting member that implements the above-mentioned function can have various structures. In some embodiments, referring to Figures 5A, 5B, and 6, the mounting member is an annular mounting member 7. This annular mounting member 7 is disposed on the surface of the electron beam generating chamber 1 on the side where the lead-out port 101 is located, for example, on the surface of the shielding chamber cover 32 away from the electron beam generating chamber 1. The annular hole 73 of the annular mounting member 7 is the aforementioned hollow portion and is coaxially disposed with the lead-out port 101. The opening area of ​​the annular hole 73 should be greater than or equal to the maximum opening area of ​​the lead-out control port 201.

[0066] The annular mounting member 7 is formed with a plurality of guide grooves 74 arranged in sequence along the circumference of the annular mounting member 7. Each guide groove 74 has an opening 741 formed on the inner circumference of the annular mounting member 7. Each shielding plate 21 is disposed in a corresponding manner in each guide groove 74 and is capable of extending into the annular hole 73 through the opening 741 along the radial direction of the outlet control port 201. Furthermore, the inner circumference of each shielding plate 21 and the opening 741 are both oriented toward the annular hole 73. Specifically, when each shielding plate 21 is fully retracted into the corresponding guide groove 74, the opening area of ​​the outlet control port 201 is equal to the opening area of ​​the annular hole 73. When each shielding plate 21 extends into the annular hole 73 along the radial direction of the outlet control port 201 through the opening 741, the plurality of shielding plates 21 shield the edge area of ​​the annular hole 73 of the annular mounting member 7. Simultaneously, the inner circumferences of the plurality of shielding plates 21 enclose the annular hole 73 to form the outlet control port 201. Furthermore, in some embodiments, the orthographic projection shape of the guide groove 74 on the radial cross section of the annular mounting member 7 is adapted to the orthographic projection shape of the baffle plate 21 on the radial cross section of the annular mounting member 7. For example, the baffle plate 21 is a flat plate with four side surfaces, one of which is the inner peripheral surface 21a, for example, a circular arc surface, and the other three side surfaces are all planes, wherein the plane opposite to the inner peripheral surface 21a is the outer peripheral surface 21b, and the outer peripheral surface 21b is perpendicular to the other two planes 21c, and the other two planes 21c are perpendicular to the inner peripheral surface 21a. The moving directions of the baffle plate 21 are parallel to each other (i.e., parallel to the radial direction of the lead-out control port 201). In this case, correspondingly, as shown in FIG5A , the guide groove 74 has three side surfaces, which respectively correspond to the three side surfaces of the baffle plate 21 except the inner circumference. One of the side surfaces 742 is opposite to the opening 741. The other two side surfaces 743 of the guide groove 74 parallel to the radial direction of the lead-out control port 201 can guide the baffle plate 21, so that the baffle plate 21 can move along the radial direction of the lead-out control port 201.

[0067] In some embodiments, the portion of each baffle plate 21 extending into the hollow portion (e.g., the annular hole 73) and the portion of the two adjacent baffle plates 21 extending into the hollow portion (e.g., the annular hole 73) partially overlap in their orthographic projections on the radial cross-section of the outlet 101 (e.g., in the axial direction of the annular mounting member 7). This can achieve a reduction in the opening area of ​​the outlet control port 201. Specifically, as shown in FIG5B , the bottom surface of the guide groove 74 is an inclined surface inclined relative to the radial cross-section of the annular mounting member 7, and the plurality of guide grooves 74 are all inclined in the same direction, that is, the depth of each guide groove 74 increases from one side surface 743 to the other side surface 743. In this way, under the guiding action of the guide groove 74, the portion of the baffle plate 21 extending into the annular hole 73 is also inclined to achieve overlap between adjacent baffle plates 21 and avoid motion interference. Furthermore, for two adjacent guide grooves 74, the maximum depth of one guide groove 74 is d11, and the minimum depth is d12; the maximum depth of the other guide groove 74 is d21, and the minimum depth is d22. In this case, the absolute value of the difference between the minimum depth d12 of one guide groove 74 and the maximum depth d21 of the other guide groove 74 is equal to the thickness of the baffle 21, so that the two adjacent baffles 21 can be ensured to be in contact, thereby forming a closed outlet control port 201.

[0068] In some embodiments, a moving channel 79 is formed on the side of each guide groove 74 relative to the hollow portion (e.g., the annular hole 73), extending radially from the lead-out control port 201 to the outer side of the mounting member facing away from the side (e.g., the outer peripheral surface of the annular mounting member 7). Furthermore, as shown in FIG3A and FIG3B , the electron beam generator further comprises a plurality of connecting rods 22 and a plurality of linear drive sources 23, each connecting rod 22 being correspondingly disposed in each moving channel 79, and each connecting rod 22 having one end connected to each shielding plate 21 and the other end connected to each linear drive source 23. Each linear drive source 23 is configured to drive the corresponding shielding plate 21 to move radially from the lead-out control port 201 via the corresponding connecting rod 22. The linear drive source 23 is, for example, a stepping motor, and a plurality of stepping motors can drive the plurality of shielding plates 21 to move synchronously.

[0069] In some embodiments, as shown in FIG7 , the electron beam generator further includes an annular fixing member 8, which is fixedly connected to the annular mounting member 7 and is used to constrain each shielding plate 21 within a corresponding guide groove 74. The annular fixing member 8 and the annular mounting member 7 are fixedly connected, for example, using a plurality of screws. An annular hole 82 of the annular fixing member 8 is coaxially arranged with the outlet 101, and the opening area of ​​the annular hole 82 is, for example, the same as the opening area of ​​the annular hole 73 of the annular mounting member 7.

[0070] In some embodiments, a positioning structure is provided between the annular fixing member 8 and the annular mounting member 7 to define the relative position of the annular fixing member 8 and the annular mounting member 7. The positioning structure may have various structures. For example, the positioning structure may include a protruding structure formed on the surface of the annular mounting member 7 where the guide groove 74 is located (i.e., surface 71 in Figures 5A and 6). The protruding structure forms a positioning groove on the annular mounting member 7 to define the relative position of the annular fixing member 8 on the annular mounting member 7. The embodiments of the present application have no particular limitations on the protrusion structure, as long as it can define the relative position of the annular fixing member 8 on the annular mounting member 7. For example, as shown in Figures 5A, 5B, 9, and 10, the protrusion structure includes an annular protrusion 75 provided along the outer peripheral edge of the surface where the guide groove 74 of the annular mounting member 7 is located (i.e., surface 71 in Figures 5A and 6), and a protrusion 76 provided on the inner peripheral edge of the surface where the guide groove 74 of the annular mounting member 7 is located (i.e., surface 71 in Figures 5A and 6), and located between each adjacent guide groove 74. The inner peripheral surface of the annular protrusion 75 cooperates with the outer peripheral surface of the annular fixing member 8, and the surface of the protrusion 76 opposite to the annular protrusion 75 cooperates with the inner peripheral surface of the annular fixing member 8. In other words, the annular fixing member 8 is located in the annular groove formed by the annular protrusion 75 and the protrusions 76. The shape of the protrusion 76 located between each two adjacent guide grooves 74 can be adapted to the shape of the interval between each two adjacent guide grooves 74, for example, a triangular protrusion located at the inner peripheral edge of the interval.

[0071] In some embodiments, please refer to Figures 7 to 10 together. The electron beam generator also includes a plurality of limiting rods 84; a plurality of limiting channels 83 are formed on the surface of the annular fixing member 8 facing the annular mounting member 7 (i.e., the surface 81 in Figure 7), and each limiting channel 83 extends radially along the lead-out control port 201, and a channel opening 831 is formed on the inner circumferential surface of the annular fixing member 8; each limiting rod 84 is arranged in each limiting channel 83 in a one-to-one manner, and can extend into the annular hole 83 of the annular fixing member 8 through the channel opening 831 along the radial direction of the lead-out control port 201; each limiting rod 84 is stacked one-to-one on the surface of each baffle plate 21 adjacent to the annular fixing member 8, and one end of each limiting rod 84 facing the channel opening 831 is fixedly connected to the inner circumferential edge of the corresponding baffle plate 21. When the shielding plate 21 moves radially along the outlet control port 201, since each limiting rod 84 is fixedly connected to the corresponding shielding plate 21, the limiting rod 84 will slide along the limiting channel 83 driven by the shielding plate 21. With the help of the limiting rod 84, the corresponding shielding plate 21 can be limited to prevent the shielding plate 21 from tilting.

[0072] There are various ways to securely connect each limiting rod 84 to its corresponding shielding plate 21. In some embodiments, a bent portion 841 is provided on the end of each limiting rod 84 that faces the passage opening 831 and is bent toward the shielding plate 21. A fixing hole 211 is formed on the inner peripheral edge of the surface of each shielding plate 21 adjacent to the annular fixing member 8. The bent portion 841 of each limiting rod 84 is disposed in the fixing hole 211 of the corresponding shielding plate 21. This facilitates installation and removal of the limiting rod 84.

[0073] In some embodiments, as shown in FIG1 , the shielding assembly 2 is disposed between the electron beam generating cavity 1 and the extraction electrode 6 , and the annular mounting member 7 and the annular fixing member 8 are both made of insulating materials to electrically insulate the electron beam generating cavity 1 from the extraction electrode 6 . Thus, the extraction electrode 6 can be disposed on the surface of the annular fixing member 8 facing away from the annular mounting member 7 (i.e., the surface opposite to surface 81 in FIG7 ), thereby facilitating the installation of the extraction electrode 6 . Furthermore, the shielding plate 21 can be made of insulating materials or metal materials.

[0074] In summary, the electron beam generator provided in the embodiments of the present application can adjust the extraction area of ​​the extraction port of the electron beam generating cavity through the shielding assembly. During the movement of electrons, by controlling the shielding assembly to adjust the extraction area of ​​the extraction port according to the amplitude of the plasma density within the electron beam generating cavity, the extraction area can be adapted to the changes in the plasma sheath morphology, so that the electron extraction efficiency is always maintained at a relatively large value, thereby effectively improving the performance and stability of the electron beam generator.

[0075] As another technical solution, referring to FIG. 11 , an embodiment of the present application further provides an ion beam etching apparatus, comprising a process chamber 200, and an ion source generating device 300 and a carrier device 400 disposed relative to each other in a first direction within the process chamber 200. The ion source generating device 300 is configured to generate an ion beam and direct it into the process chamber 200 along the first direction so that the ion beam can move toward the carrier device 400 on the opposite side. The carrier device 400 is configured to support a wafer and also to apply radio frequency power to the wafer.

[0076] The ion beam etching apparatus further includes the electron beam generator 100 provided in an embodiment of the present application. The electron beam generator 100 is disposed on a cavity of a process chamber 200, and an outlet of the electron beam generating cavity is in communication with the process chamber 200 and faces a second direction for extracting an electron beam into the process chamber 200. The second direction forms an angle with the first direction, for example, a 90° angle. Specifically, the first direction is, for example, a horizontal direction, and the second direction is a vertical direction.

[0077] In some embodiments, a sensor and a controller are further included. The sensor is used to obtain the plasma density in the electron beam generating cavity. The controller is used to control the electron beam generator 100 to adjust the extraction area of ​​the extraction port according to the plasma density obtained by the sensor.

[0078] The controller is also used to control the operation of the electron beam generator 100. Taking the electron beam generator 100 shown in FIG1 as an example, the specific control method of the controller includes: controlling the corresponding gas supply device to pass an inert gas into the electron beam generating cavity 1 through the gas inlet channel in the ion collecting electrode 5; then, controlling the RF source to turn on and load RF power to the RF coil 4 to excite the inert gas inside the electron beam generating cavity 1 to form a plasma. Under the action of the spatial electric field formed between the ion collecting electrode 5 and the extraction electrode 6, the electrons in the plasma move from the electron extraction port 101 to the outside of the electron beam generating cavity 1 and enter the process chamber 200. Moreover, during the movement of the electrons, the controller controls the shielding component 2 in the electron beam generator 100 to adjust the extraction area of ​​the extraction port 101 according to the magnitude of the plasma density amplitude inside the electron beam generating cavity 1. In this way, the extraction area of ​​the extraction port can adapt to the changes in the plasma sheath morphology, so that the electron extraction efficiency is always maintained at a relatively large value, thereby effectively improving the performance and stability of the electron beam generator.

[0079] The ion beam etching equipment provided in the embodiment of the present application can maintain the electron extraction efficiency at a relatively large value by adopting the above-mentioned electron beam generator provided in the embodiment of the present application, thereby optimizing the process effect.

[0080] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present application, and the present application is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present application, and such modifications and improvements are also considered to be within the scope of protection of the present application.

Claims

1. An electron beam generator, characterized in that: include: An electron beam generating cavity having an outlet; A shielding component, movably disposed outside the electron beam generating cavity; The shielding component is configured to shield the outlet, and the outlet area of ​​the outlet can be adjusted by adjusting the position of the shielding component.

2. The electron beam generator according to claim 1, characterized in that The shielding assembly includes a plurality of shielding plates arranged in sequence in the circumferential direction, the inner circumferential surfaces of the plurality of shielding plates together enclose an outlet control port, and the outlet control port is arranged corresponding to the outlet; The plurality of shielding plates are all capable of moving in the radial direction of the outlet control port, and surround the outlet control port with different opening areas at different positions in the radial direction of the outlet control port.

3. The electron beam generator according to claim 2, characterized in that The outlet control port is coaxial with the outlet port.

4. The electron beam generator according to claim 2, characterized in that: The electron beam generator further comprises a mounting member, the mounting member is provided with a guide groove, the shielding plates are correspondingly arranged in the guide groove, and each guide groove is used to enable the corresponding shielding plate to move along the radial direction of the lead-out control port.

5. The electron beam generator according to claim 4, characterized in that The mounting member is also provided with a hollow portion communicating with the guide groove, wherein the hollow portion at least partially overlaps with an orthographic projection of the outlet on a radial cross section of the outlet; The shielding plate can extend into the hollow portion along the radial direction of the outlet control port.

6. The electron beam generator according to claim 5, characterized in that The mounting member is an annular mounting member, and the annular hole of the annular mounting member is coaxially arranged with the outlet; Each of the guide grooves is formed with an opening on the inner circumference of the annular mounting member; each of the shielding plates can extend into the annular hole through the opening along the radial direction of the lead-out control port, and the inner circumference of each of the shielding plates and the opening are both facing the annular hole.

7. The electron beam generator according to claim 5, characterized in that The portion of each shielding plate extending into the hollow portion overlaps with the orthographic projection of the portions of two adjacent shielding plates extending into the hollow portion on the radial cross section of the outlet.

8. The electron beam generator according to claim 7, characterized in that The overlapping parts of each shielding plate and two adjacent shielding plates are respectively located on different sides of the two adjacent shielding plates.

9. The electron beam generator according to claim 5, characterized in that: A moving channel is formed on the side of each guide groove relative to the hollow portion and passes through the radial direction of the lead-out control port to the outer side of the mounting member away from the side; The electron beam generator also includes a plurality of connecting rods and a plurality of linear drive sources, each of the connecting rods is correspondingly arranged in each of the moving channels, and one end of each of the connecting rods is correspondingly connected to each of the baffles, and the other end is correspondingly connected to each of the linear drive sources; each of the linear drive sources is used to drive the corresponding baffle to move radially along the lead-out control port through the corresponding connecting rod.

10. The electron beam generator according to claim 6, characterized in that The electron beam generator further comprises an annular fixing member, which is fixedly connected to the annular mounting member and is used to restrict each of the shielding plates in the corresponding guide groove.

11. The electron beam generator according to claim 10, characterized in that A positioning structure is provided between the annular fixing member and the annular mounting member, for limiting the relative position of the annular fixing member and the annular mounting member.

12. The electron beam generator according to claim 11, characterized in that The positioning structure comprises a protruding structure formed on the surface of the annular mounting member where the guide groove is located. The protruding structure forms a positioning groove on the annular mounting member for limiting the relative position of the annular fixing member on the annular mounting member.

13. The electron beam generator according to claim 12, characterized in that The protrusion structure includes an annular protrusion arranged along the outer peripheral edge of the surface of the annular mounting member where the guide groove is located, and a protrusion arranged on the inner peripheral edge of the surface of the annular mounting member where the guide groove is located and located between each adjacent two guide grooves, the inner peripheral surface of the annular protrusion matches the outer peripheral surface of the annular fixing member; the surface of the protrusion relative to the annular protrusion matches the inner peripheral surface of the annular fixing member.

14. The electron beam generator according to claim 10, characterized in that The electron beam generator also includes a plurality of limit rods; A plurality of limiting channels are formed on the surface of the annular fixing member facing the annular mounting member, each of the limiting channels extends in the radial direction of the lead-out control port, and a channel opening is formed on the inner circumferential surface of the annular fixing member; each of the limiting rods is correspondingly arranged in each of the limiting channels, and can extend into the annular hole of the annular fixing member through the channel opening in the radial direction of the lead-out control port; The limiting rods are overlapped one by one on the surface of each shielding plate adjacent to the annular fixing member, and one end of each limiting rod facing the channel opening is fixedly connected to the inner peripheral edge of the corresponding shielding plate.

15. The electron beam generator according to claim 14, characterized in that Each of the limiting rods is provided with a bent portion bent in a direction close to the shielding plate at one end facing the channel opening; each of the shielding plates is formed with a fixing hole at the inner peripheral edge of the surface adjacent to the annular fixing member; The bent portion of each of the limiting rods is arranged in the fixing hole of each of the corresponding shielding plates.

16. An ion beam etching device, comprising a process chamber, and an ion source generating device and a carrying device arranged in the process chamber relative to each other in a first direction, characterized in that: It also includes the electron beam generator as described in any one of claims 1 to 15, wherein the electron beam generator is arranged on the cavity body of the process chamber, and the outlet is connected to the process chamber and faces a second direction for leading the electron beam into the process chamber, wherein the second direction is at an angle to the first direction.

17. The ion beam etching device according to claim 16, characterized in that: It also includes a sensor and a controller, wherein the sensor is used to obtain the plasma density in the electron beam generating cavity, and the controller is used to control the shielding component in the electron beam generator to adjust the lead-out area of ​​the lead-out port according to the plasma density obtained by the sensor.

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