Electron beam diaphragm and beam shutter integrated device and electron optical system

Abstract

The application provides an electron beam diaphragm and beam shutter integrated device and an electron optical system, which comprises a base, a positive electrode, a first diaphragm sheet and a second diaphragm sheet; the inside of the base is provided with a first negative electrode plate and a second negative electrode plate, and the top of the base is provided with a first diaphragm sheet mounting hole and a second diaphragm sheet mounting hole; the positive electrode is in a strip shape, the upper part of the positive electrode is matched with the base, the first negative electrode plate and the second negative electrode plate are separately arranged on the two sides of the upper part of the positive electrode, the first negative electrode plate and the positive electrode form a first beam shutter, and the second negative electrode plate and the positive electrode form a second beam shutter; the lower part of the positive electrode is provided with a knife slot structure; the first diaphragm sheet and the second diaphragm sheet are respectively mounted in the first diaphragm sheet mounting hole and the second diaphragm sheet mounting hole; the first diaphragm sheet is located above the first beam shutter, and the second diaphragm sheet is located above the second beam shutter. The application adopts an integrated design for the beam shutter and the diaphragm, has a simple and compact structure, is convenient to assemble and debug, and achieves the purposes of fast shutdown speed and small tailing.

Description

Technical Field

[0001] The present application belongs to the technical field of electron beam processing and testing in integrated circuit production, and in particular relates to an integrated electron beam aperture and beam gate device and an electron optical system. Background Art

[0002] Electron beam lithography uses an electron beam emitted by an electron gun to form an electron beam spot after being focused and deflected by an electron optical system. The electron beam spot is scanned on the surface of a wafer coated with photosensitive resin and selectively exposed according to the graphic file to form a customized pattern.

[0003] Electron beam lithography requires a very small electron beam spot, typically less than 10 nm. However, the spot size of the electron beam emitted by an electron gun is generally very large. Even with the converging effect of a lens, it still cannot meet the requirements. This requires an aperture to further reduce the beam spot size. The aperture is a very important step in the electron beam focusing process. It not only affects the size of the electron beam spot, but also directly affects the size of the electron beam current.

[0004] A beam gate is used to control the on / off switching of an electron beam. Its operating principle is to place a pair of parallel plates symmetrically at appropriate locations along the electron beam axis. When a DC voltage is applied to the plates, the electric field deflects the electron beam away from the optical axis, typically blocking it at an intermediate aperture, thereby "switching off" the electron beam.

[0005] In current applications, apertures and beam gates are typically installed as separate components at different locations within the optical column. Theoretically, there are multiple mounting locations for the beam gate, typically at the focal point of the second-stage lens. Two common locations for the aperture are above the beam gate and at the third-stage lens. Apertures typically have only a single aperture, while beam gates have only a single beam path.

[0006] Existing beam gates are large and complex in structure. Furthermore, the beam gate and aperture are separate components, mounted at different locations within the optical system. This results in a large optical column and bulky equipment. Furthermore, the larger beam gate size increases the spacing between the beam gate plates, which in turn increases the required cutoff voltage and the complexity of the control circuit. Furthermore, the large spacing between the beam gate plates makes it more likely that the beam spot will move across the substrate when the electron beam is blocked by the beam gate, causing smearing.

[0007] In addition, the intercepted electron beam is deflected and bombards the beam gate plate or the lower aperture, causing surface contamination and aging of the beam gate plate or the lower aperture, shortening the maintenance cycle and affecting normal use. Summary of the Invention

[0008] In order to overcome the problems existing in the related art, the embodiment of the present application provides an integrated device of electron beam aperture and beam gate and electron optical system, so that the beam gate and aperture adopt an integrated design with a simple and compact structure and easy assembly and debugging, so as to achieve the purpose of fast shutdown speed and small tailing.

[0009] This application is achieved through the following technical solutions:

[0010] In a first aspect, an embodiment of the present application provides an integrated electron beam stop and beam gate device, comprising:

[0011] A base, a positive electrode, a first aperture blade, and a second aperture blade;

[0012] The base is provided with a first negative plate and a second negative plate inside, and a first aperture piece mounting hole and a second aperture piece mounting hole on the top;

[0013] The positive electrode is in the shape of a long strip, the upper part of the positive electrode is matched with the base, the first negative plate and the second negative plate are separated on both sides of the upper part of the positive electrode, a first beam gate is formed between the first negative plate and the positive electrode, and a second beam gate is formed between the second negative plate and the positive electrode; the lower part of the positive electrode is provided with a knife-edge groove structure;

[0014] The first aperture plate and the second aperture plate are respectively installed in the first aperture plate installation hole and the second aperture plate installation hole; the first aperture plate is located above the first beam gate, and the second aperture plate is located above the second beam gate.

[0015] In a possible implementation of the first aspect, the base includes: a cylindrical hollow structure and a mounting seat;

[0016] A first groove and a second groove are provided inside the cylindrical hollow structure. The central axis of the first groove coincides with the central axis of the second groove, and the width of the first groove is smaller than the width of the second groove. The first negative electrode plate and the second negative electrode plate serve as two side walls of the first groove. When the positive electrode is mated with the base, the positive electrode is located between the first negative electrode plate and the second negative electrode plate.

[0017] The first aperture piece mounting hole and the second aperture piece mounting hole are located at the top of the cylindrical hollow structure, and are respectively arranged on both sides of the central axis;

[0018] The mounting seat is arranged on one side of the cylindrical hollow structure, and the lower surface thereof is flush with the lower surface of the cylindrical hollow structure;

[0019] A positive electrode mounting hole is provided on the bottom surface of the first groove, and a first fixing bolt passes through the positive electrode mounting hole to fix the positive electrode on the base;

[0020] The mounting seat is provided with a base mounting hole, and the second fixing bolt passes through the base mounting hole to fix the base on other mechanisms.

[0021] In a possible implementation manner of the first aspect, the upper part of the anode is provided with two threaded holes matched with the first fixing bolts.

[0022] The lower part of the anode is below the base, the knife-edge groove structure is a groove provided on both sides of the lower part of the anode, and a knife-edge plane structure is provided at the end of the groove, and the plane in the groove is at a preset distance from the outer side plane of the upper part of the anode.

[0023] In a possible implementation manner of the first aspect, the lower part of the anode is in an inverted T shape and connected with the upper part of the anode, and the connection between the upper part of the anode and the lower part of the anode is in a circular arc shape.

[0024] In a possible implementation manner of the first aspect, the distance between the two side walls of the upper part of the anode and the first negative plate and the second negative plate is not more than 1 mm; and after power-on, the two side walls of the upper part of the anode and the first negative plate and the second negative plate form two uniform electrostatic fields.

[0025] In a possible implementation manner of the first aspect, the device further comprises two insulating positioning columns and two gaskets.

[0026] The two insulating positioning columns, the two gaskets, the anode mounting hole and the first fixing bolt are matched, and are used to connect the base and the anode.

[0027] The two insulating positioning columns are opposite to the anode mounting hole and are located outside the base; and the two gaskets are located between the anode and the base.

[0028] In a possible implementation manner of the first aspect, the insulating positioning column and the gasket are ceramic materials.

[0029] In a possible implementation manner of the first aspect, the aperture of the first light hole on the first diaphragm sheet is different from the aperture of the second light hole on the second diaphragm sheet.

[0030] In a possible implementation manner of the first aspect, the base mounting hole is matched with the second fixing bolt to fix the base on the fine adjustment mechanism; the fine adjustment mechanism selects different diaphragm sheets by controlling the position and rotation angle of the base, and controls the position of the center of the light hole; the diaphragm sheet comprises a first diaphragm sheet and a second diaphragm sheet.

[0031] In the second aspect, the embodiments of the present application provide an electron optical system, comprising the electron beam diaphragm and beam shutter integrated device of any one of the first aspect, and the electron beam diaphragm and beam shutter integrated device is installed behind the second-stage lens of the electron optical system.

[0032] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0033] In the embodiment of the present application, by designing the shapes of the base and the positive electrode, the upper part of the positive electrode cooperates with the cylindrical hollow structure of the base to form two beam gates, thereby reducing the size of the beam gate. A knife-edge groove structure is provided at the lower part of the positive electrode, which can receive the bombardment of the electron beam shut off by the beam gate, and avoid the intercepted electron beam from bombarding and contaminating the positive electrode or the lower aperture of the positive electrode. By providing two apertures, it is convenient to switch according to the processing requirements when the equipment is used, thereby improving the processing efficiency. The beam gate and the aperture are designed as an integrated whole, and the aperture is designed on the base. There is an electron beam gate corresponding to the bottom of each aperture. During use, each beam gate switches synchronously with the corresponding aperture, making the overall structure simple and compact, and easy to assemble and debug, so as to achieve the purpose of fast shutdown speed and small tailing.

[0034] The beneficial effects of the second aspect mentioned above refer to the beneficial effects of the first aspect and will not be repeated here.

[0035] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0037] Figure 1 This is a structural assembly diagram of an integrated electron beam stop and beam gate device provided in one embodiment of the present application;

[0038] Figure 2 This is an exploded view of parts of an integrated electron beam stop and beam gate device provided in one embodiment of the present application;

[0039] Figure 3 This is a schematic diagram of the principle of an integrated electron beam stop and beam gate device provided in one embodiment of the present application;

[0040] Figure 4 This is a front view of a base provided by an embodiment of the present application;

[0041] Figure 5 1 is a three-view diagram of a base provided in one embodiment of the present application;

[0042] Figure 6 This is a structural diagram of an aperture piece provided by an embodiment of the present application installed in an aperture piece mounting hole;

[0043] Figure 7 This is a front view of the positive electrode provided by one embodiment of the present application;

[0044] Figure 8 1 is a three-view diagram of a positive electrode provided in one embodiment of the present application;

[0045] Figure 9 1 is a comparative schematic diagram of the blade plane structure P1 and the vertical plane structure P2 at the lower part of the positive electrode provided in one embodiment of the present application;

[0046] Figure 10 Schematic diagram of the position of the electron beam stop and beam gate integrated device in the optical column provided by one embodiment of the present application;

[0047] Figure 11 This is a schematic diagram of the application analysis of the integrated electron beam stop and beam gate device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0048] In the following description, specific details such as specific system structures and techniques are provided for purposes of illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obscuring the description of the present application with unnecessary detail.

[0049] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections thereof.

[0050] It will also be understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0051] It should also be understood that the term "relative" as used in this specification and the appended claims refers to relative positions in mechanical movement.

[0052] As used in this specification and the appended claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0053] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0054] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0055] Photolithography is a key process in semiconductor manufacturing, directly determining the manufacturing quality of semiconductor devices. Compared to optical exposure, electron beam lithography offers unique advantages in photolithography, making it widely used in the manufacture of power devices, specialty devices, novel circuits, and in the research of nanodevices.

[0056] The electron beam lithography system mainly consists of an electron optical system, an ultra-high vacuum system, a computer control system, a motion control system, and a high-voltage control system. The electron optical system, also known as the optical column, is a crucial component of the lithography system and primarily includes the electron gun, electromagnetic lens, deflection coil, stigmator coil, aperture, beam gate, and electron detector.

[0057] Electron beam lithography requires a very small electron beam spot. The aperture is used to change the shape or size of the electron beam, filter out off-axis electrons in the electron beam, and reduce the influence of electron lens spherical aberration. The smaller the aperture, the smaller the aperture angle and the greater the depth of field. There are usually multiple apertures at different positions along the lower part of the optical column, and the middle aperture limits the divergence of the electron beam. The shading plate of the adjustable aperture is equipped with multiple apertures of different sizes to limit the final convergence angle of the electron beam to the substrate to optimize the focusing quality and beam current density. The convergence angle of the electron beam affects not only the final beam spot size at the substrate surface, but also the beam current density of the final beam spot at the substrate surface.

[0058] As described in the background, in current applications, the aperture and beam gate are typically used as separate components, resulting in several operational deficiencies. Since the aperture and beam gate are separate components, adjusting the adjustable aperture's operating position while leaving the beam gate unchanged can affect the beam gate's ability to shut off the electron beam. Therefore, adjusting the beam gate's position again requires high mechanical position calibration accuracy for the aperture.

[0059] There are also some variable-size narrow slit rectangular apertures in the existing technology. In essence, the size of the narrow slit aperture is adjusted by changing the rectangular size through a baffle. The structure is complex and cannot solve the above-mentioned problems caused by the aperture and beam gate being two independent components. In the application of aperture size at the micron level, the feasibility is poor.

[0060] Based on the above problems, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] Figure 1 This is the structural diagram of the integrated electron beam aperture and beam gate device, refer to Figure 1 , a device integrating an electron beam aperture and a beam gate, comprising: a base 100, a positive electrode 200, a first aperture piece 300 and a second aperture piece 400.

[0062] The base 100 is provided with a first negative plate and a second negative plate inside, and a first aperture piece mounting hole 103 and a second aperture piece mounting hole 104 are provided on the top. Figure 2 shown.

[0063] The positive electrode 200 is in the shape of a long strip. The upper portion 201 of the positive electrode 200 is matched with the base 100. The first negative electrode plate and the second negative electrode plate are separated on both sides of the upper portion 201 of the positive electrode 200. A first beam gate is formed between the first negative electrode plate and the positive electrode 200, and a second beam gate is formed between the second negative electrode plate and the positive electrode 200. Figure 2 The lower portion 202 of the positive electrode is provided with a knife-edge groove structure 203 .

[0064] The first aperture plate 300 and the second aperture plate 400 are respectively installed in the first aperture plate installation hole 103 and the second aperture plate installation hole 104; the first aperture plate 300 is located above the first beam gate, and the second aperture plate 400 is located above the second beam gate.

[0065] The aperture of the first aperture blade mounting hole 103 and the aperture of the second aperture blade mounting hole 104 can be the same or different. If the aperture of the first aperture blade mounting hole 103 and the aperture of the second aperture blade mounting hole 104 are the same, the number of replacement times for the same-sized aperture can be reduced. If the aperture of the first aperture blade mounting hole 103 and the aperture of the second aperture blade mounting hole 104 are different, aperture blades of different sizes can be installed, and the aperture can be directly switched to meet the working requirements during use.

[0066] For example, the diaphragm is made of platinum or molybdenum because the electron beam has high energy and continuously bombards the diaphragm. Cleaning the contaminated diaphragm requires high-temperature burning. The diaphragm is a consumable part and needs to be replaced regularly.

[0067] For example, see Figure 2 and Figure 3The upper portion 201 of the positive electrode is inserted into the cylindrical hollow structure 101 of the base 100. A predetermined distance is established between the first negative electrode plate and the positive electrode 200, thereby forming a first beam gate. Similarly, a predetermined distance is established between the second negative electrode plate and the positive electrode 200, thereby forming a second beam gate. The electrical and mechanical properties of the first and second beam gates are identical.

[0068] For example, the first aperture piece 300 and the first aperture piece mounting hole 103 are combined to form the first aperture of the device; the second aperture piece 400 and the second aperture piece mounting hole 104 are combined to form the second aperture of the device. In the horizontal direction, the approximate positional relationship between the first aperture, the second aperture, and the first beam gate and the second beam gate is as follows: Figure 3 shown.

[0069] The beam gate is used to control the on and off of the electron beam. Parallel plates are symmetrically set on both sides of the electron beam axis, namely the first negative plate and the positive electrode 200, and the second negative plate and the positive electrode 200. When a certain DC voltage is applied to the parallel plates, the electron beam will be deflected and deviate from the optical axis due to the effect of the electric field. It will generally be blocked by the first aperture plate or the second aperture plate, thereby achieving the purpose of "turning off" the electron beam. During the pattern scanning, Beam shutter Can be driven automatically.

[0070] For example, by designing the shapes of the base 100 and the positive electrode 200, the upper portion 201 of the positive electrode cooperates with the first and second negative plates of the base 100 to form two beam gates, reducing the size of the beam gates. A knife-edge groove structure 203 is provided on the lower portion 202 of the positive electrode. This structure can receive the electron beam blocked by the beam gate, preventing the intercepted electron beam from bombarding and contaminating the positive electrode 200 or the aperture.

[0071] The beam gate and aperture utilize an integrated design. The apertures are mounted on the base 100, with each aperture corresponding to an electron beam gate. During operation, each beam gate switches synchronously with the corresponding aperture, resulting in a simple and compact overall structure and easy assembly and commissioning. The integrated device is installed after the second-stage lens, with the aperture mounted above the negative plate of the beam gate. This reduces the beam current after passing through the aperture, facilitating beam gate control and reducing photolithography tailing, thereby achieving fast shutdown speeds and minimal tailing.

[0072] Specifically, such as Figure 2 、 Figure 4 and Figure 5 As shown, the base 100 includes a cylindrical hollow structure 101 and a mounting seat 102 .

[0073] A first groove and a second groove are provided inside the cylindrical hollow structure 101. The central axis of the first groove coincides with the central axis of the second groove, and the width of the first groove is smaller than the width of the second groove. The first negative electrode plate and the second negative electrode plate are the two side walls of the first groove. When the positive electrode 200 is matched with the base 100, it is located between the first negative electrode plate and the second negative electrode plate.

[0074] Exemplarily, the cylindrical hollow structure 101 is a semi-enclosed double-layer groove structure, which is a groove with a closed top and a through bottom. The groove includes a first groove and a second groove. The bottom surface of the first groove is the same as the bottom surface of the groove. The notch of the second groove is the notch of the groove. The notch of the first groove penetrates the bottom surface of the second groove, forming a double-layer groove structure. The double-layer groove structure as a whole is a structure in which a stepped groove is set in a cylinder. The positive electrode 200 is matched with the base 100 through the unenclosed part. The upper part 201 of the positive electrode is inserted into the groove. The first negative electrode plate and the second negative electrode plate are located on both sides of the bottom surface of the first groove and are the inner side walls of the first groove.

[0075] The first aperture piece mounting hole 103 and the second aperture piece mounting hole 104 are located at the top of the cylindrical hollow structure 101 and are respectively arranged on both sides of the above-mentioned central axis.

[0076] For example, Figure 6 As shown, the first aperture plate mounting hole 103 and the second aperture plate mounting hole 104 are both stepped through holes.

[0077] The first aperture plate mounting hole 103 includes a first stepped groove and a first through hole. The first aperture of the first aperture plate 300, the first stepped groove, and the first through hole are coaxially mounted about the central axis of the first aperture plate. The first aperture plate is mounted within the first stepped groove. The dimensions of the first stepped groove are identical to those of the first aperture plate 300 within a preset error range, limiting the position of the first aperture plate 300. The aperture of the first through hole is much larger than the aperture of the first aperture plate 300, but smaller than the dimensions of the first aperture plate. The aperture of the first aperture on the first aperture plate 300 can be 20 μm.

[0078] The second aperture plate mounting hole 104 includes a second stepped groove and a second through hole. The second aperture plate 400, the second stepped groove, and the second through hole are coaxially mounted about the central axis of the second aperture plate. The second aperture plate is mounted within the second stepped groove. The dimensions of the second stepped groove are identical to those of the second aperture plate 400 within a predetermined tolerance range, thus limiting the position of the second aperture plate 400. The aperture of the second through hole is much larger than that of the second aperture plate 300, but smaller than that of the second aperture plate. The aperture of the second aperture in the second aperture plate 400 can be 10 μm.

[0079] The distance between the central axes of the first light hole and the second light hole can be set to 3 mm.

[0080] For example, the size of the aperture of the device is determined by the size of the aperture on the aperture plate. By providing two aperture plates with different apertures, two apertures with different apertures are formed, which facilitates switching of the apertures according to the processing requirements during use of the device, thereby improving processing efficiency.

[0081] The mounting seat 102 is disposed on one side of the cylindrical hollow structure 101 , and the lower surface thereof is flush with the lower surface of the cylindrical hollow structure 101 .

[0082] For example, the mounting base 102 and the cylindrical hollow structure 101 may be integrally formed, or may be connected together by welding or other methods.

[0083] The bottom surface of the first groove is provided with a positive electrode mounting hole 105, through which a first fixing bolt 500 passes to fix the positive electrode 200 to the base 100. The mounting base 102 is provided with a base mounting hole 106, through which a second fixing bolt 800 passes to fix the base 100 to other mechanisms.

[0084] Illustratively, the positive electrode mounting hole 105 is provided on the bottom surface of the first recess within the cylindrical hollow structure 101. Two positive electrode mounting holes 105 may be provided. The other mechanism may be a related mechanism or device in the optical system capable of connecting to the aperture, such as the fine adjustment mechanism described below. The fixing bolts may be replaced with other connecting structures such as screws.

[0085] For example, the size of the base 100 is no larger than 10 mm×10 mm×30 mm. The cooperation between the positive electrode 200 and the base 100 can make the overall structure of the device compact and small in size.

[0086] Specifically, such as Figure 2 、 Figure 7 and Figure 8 As shown, the positive electrode 200 includes a positive electrode upper portion 201 and a positive electrode lower portion 202 .

[0087] The upper portion 201 of the positive electrode is provided with two threaded holes 204 that engage with the first fixing bolt 500. The lower portion 202 of the positive electrode is located below the base 100. The knife-edge groove structure 203 is a groove provided on both sides of the lower portion 202 of the positive electrode, with a knife-edge flat structure provided at the end of the groove. The flat surface within the groove is separated from the outer flat surface of the upper portion 201 of the positive electrode by a predetermined distance. The lower portion 202 of the positive electrode is connected to the upper portion 201 of the positive electrode in an inverted T-shape, and the connection between the upper portion 201 and the lower portion 202 of the positive electrode is designed to be circular.

[0088] For example, a semi-open and semi-closed knife-edge groove structure 203 is machined on both sides of the lower portion 202 of the positive electrode. The knife-edge groove structure includes grooves on both sides and a knife-edge plane structure. The grooves on both sides extend to the end of the lower portion 202 of the positive electrode, and a knife-edge plane structure is formed at the end, i.e., an inverted T-shaped structure. The knife-edge direction faces the central axis of the corresponding light hole, and is used to receive the bombardment of the electron beam blocked by the beam gate, such as Figure 9 At P1 shown in the figure, the circle is the main bombardment area of ​​the electron beam after it is turned off. It is a knife-edge plane structure, the electron beam incident angle is close to 90 degrees, and the secondary reflection phenomenon of the electron is light. Compared with the non-knife-edge plane structure, the electron beam directly bombards the vertical surface, such as Figure 9 At point P2, the circled area represents the primary impact area of ​​the electron beam after shutdown. This vertical plane is a structure where the electron beam strikes the vertical surface at a very small angle, which can easily cause secondary reflections of the electrons, resulting in tailing and vacuum chamber contamination. Therefore, the use of knife-edge groove structure 203 effectively reduces secondary reflections and prevents the intercepted electron beam from impacting and contaminating the anode 200 or the lower aperture.

[0089] Illustratively, the junction of the upper part 201 of the positive electrode and the lower part 202 of the positive electrode is the neck 205 of the positive electrode 200. The neck 205 adopts an inwardly concave arc shape to reduce the heat transfer from the knife-edge groove structure 203 to the upper part 201 of the positive electrode, thereby reducing thermal stress.

[0090] Specifically, the distance between the two side walls of the upper part 201 of the positive electrode and the first negative plate and the second negative plate is no more than 1 mm; after power is applied, the two side walls of the upper part 201 of the positive electrode form two uniform electrostatic fields with the first negative plate and the second negative plate.

[0091] For example, the two sidewalls of the upper portion 201 of the positive electrode and the two sidewalls of the groove in the base 100 form two parallel plate electrodes. When energized, they generate two uniform electrostatic fields. These two electrostatic fields can be used to shut off the electron beam after it passes through the corresponding aperture above. The spacing of these electric fields can be varied to meet different electron optical path requirements. Each aperture is fixedly associated with a beam gate. When an aperture is adjusted to a working position concentric with the optical axis of the optical system, its corresponding beam gate also moves synchronously to a position concentric with the optical axis.

[0092] For example, the spacing between the parallel plate electrodes does not exceed 1 mm, and the spacing between the positive and negative poles of the beam gate in the device is small, which reduces the required beam gate control voltage, reduces the complexity of the beam gate control circuit, increases the electron beam shutdown frequency, and improves the equipment processing efficiency.

[0093] In practical applications, the residual charge on the gate plate must be sufficiently small and the on-off switching time must be sufficiently fast. Reducing the gate plate size and spacing helps reduce the turn-off voltage, increase the frequency of on-off switching, and reduce the contamination of the beam gate plate by the electron beam. The selection of the turn-off voltage and the design of the beam gate plate size and spacing require comprehensive consideration of the installation space for the control circuit and the optical column. The beam gate plate should be installed in a location with a smaller electron beam cross-section. Generally, a lens in front of the beam gate will generate a focal point of the electron beam at the electrical center of the beam gate plate. The most common installation location is at the outer focus of the second-stage lens.

[0094] In one embodiment, the electron beam stop and beam gate integrated device may further include: an insulating positioning column 600 and a washer 700 .

[0095] There may be multiple insulating positioning columns 600 and washers 700, such as Figure 2 As shown, in this embodiment, the number of insulating positioning columns 600 and washers 700 can be set to two.

[0096] Two insulating positioning columns 600 and two washers 700 cooperate with the positive electrode mounting hole 105 and the first fixing bolt 500 to connect the base 100 and the positive electrode 200; the two insulating positioning columns 600 are opposite to the positive electrode mounting hole 105 and are located outside the base 100; the two washers 700 are located between the positive electrode 200 and the base 100.

[0097] Illustratively, the first fixing bolt 500 passes through the insulating positioning column 600, the positive electrode mounting hole 105 of the base 100, the washer 700 and the threaded hole 204 of the positive electrode 200 in sequence, connecting the positive electrode 200 and the base 100 serving as the negative electrode together to achieve the integration of the aperture and the beam gate.

[0098] The insulating positioning column 600 and the washer 700 can be made of ceramic materials, such as Figure 2 As shown, the positioning column is a step type. By setting the step size, the first fixing bolt 500 is vertically spaced apart from the positive electrode mounting hole 105 at a preset distance, which can prevent the first fixing bolt 500 made of metal material from contacting the base 100 and causing a short circuit between the positive and negative plates, thereby ensuring electrical insulation between the base 100 and the positive electrode 200.

[0099] Illustratively, the base mounting hole 106 cooperates with the second fixing bolt 800 to fix the base 100 on the fine-tuning mechanism; the fine-tuning mechanism selects different aperture pieces by controlling the position and rotation angle of the base 100, and controls the position of the center of the light hole; the aperture pieces include a first aperture piece 300 and a second aperture piece 400, and the light hole includes a first light hole and a second light hole.

[0100] The whole device is connected to one end of the connecting rod of the fine adjustment mechanism through the fixing screw of the base 100.Figure 10 As shown, the fine-tuning mechanism, located outside the wall of the optical column vacuum chamber, is used to adjust the horizontal and vertical positions of the base 100, as well as the rotation angle along the connecting rod. This serves to align the center of the active aperture with the optical axis of the optical system. The fine-tuning mechanism uses the connecting rod to select different aperture plate mounting holes, thereby selecting different apertures. Different apertures correspond to different scale values ​​on the fine-tuning mechanism.

[0101] In one embodiment, in order to more clearly describe the structure of the electron beam stop and beam gate integrated device, Figure 2 , now the device assembly and debugging process is shown:

[0102] Step 1: Place the insulating positioning post 600 outside the positive electrode mounting hole 105. Insert the first fixing bolt 500 of the positive electrode 200 through the insulating positioning post 600 and the positive electrode mounting hole 105. Then, insert the washer 700 and connect it to the threaded hole 204 of the positive electrode 200. The knife-edge groove on the lower portion 202 of the positive electrode faces the central axis of the aperture. Following this process, the two sets of first fixing bolts 500, insulating positioning post 600, positive electrode mounting hole 105, washer 700, and threaded hole 204 are connected.

[0103] Step 2: After fixing the positive electrode 200, use a feeler gauge to check the distance between the two side walls of the upper part 201 of the positive electrode and the side walls of the inner groove of the base 100, that is, the distance between the positive electrode 200 and the first negative electrode plate and the second negative electrode plate. Adjust the distance and keep the distance between the two sides uniform, and then tighten the first fixing bolt 500.

[0104] Step 3: Install the new diaphragm into the corresponding diaphragm mounting hole and press the diaphragm tightly and flat. Observe the two diaphragms under a microscope until the 10um and 20um holes are visible.

[0105] Step 4: Set the multimeter to the 20MΩ setting, connect the two test leads to the positive terminal 200 and the base 100, and measure the insulation resistance between them. It should be infinite. If the resistance is not infinite, check whether the assembly is correct and determine whether the ceramic insulation needs to be replaced.

[0106] Step 5: Use the second fixing screw to connect and fix the base mounting hole 106 of the base 100 and the end of the operating rod of the fine-tuning mechanism, with the top of the base 100 facing the direction of the electron gun.

[0107] Step 6: Connect the control signal line of the positive electrode 200 to the first fixing bolt 500 connected to the positive electrode 200. The pattern generator of the equipment controls the beam gate driver according to the processing pattern requirements. The beam gate driver outputs a DC voltage applied to the positive electrode 200 through the signal line. The typical value is between 10V and 15V, which shuts off the electron beam.

[0108] Step 7: Use the fine-tuning knobs on the external adjustment mechanism to adjust the device's x- and y-direction positions, as well as the horizontal position of the base 100. Adjustment can be manual or automatic. The spacing between the first aperture blade mounting hole 103 and the second aperture blade mounting hole 104 can be approximately 3 mm. The corresponding y-direction scale on the fine-tuning knob allows the center of the aperture to be roughly adjusted to the working position, i.e., the optical axis of the electron optical system. Further fine-tuning requires the use of the device's built-in imaging system.

[0109] Step 8: Use the installed compact electron beam aperture and beam gate integrated device to perform parameter design and application analysis.

[0110] The first and second negative plates (two flat surfaces inside the groove) on the inner side of the base 100 and the two side surfaces of the upper portion 201 of the positive electrode respectively form the two parallel plates of the beam gate structure. Two uniform electric fields are formed under the action of the deflection voltage. Electrons in the electron beam have a charge q and a mass m. In the uniform electric field of field strength E, they are subjected to a constant electric force F. The direction of force F is perpendicular to the optical axis and directed toward the positive electrode 200. Electrons are emitted from the cathode filament of the electron gun, pass through the extraction and focusing electrodes, and are then subjected to the electron gun's high-voltage acceleration U0, undergoing uniformly accelerated linear motion, ultimately achieving a velocity v0. The electron beam enters the beam gate with an initial velocity v0 and, under the action of the deflection voltage U between the beam gate plates, undergoes a quasi-parallel deflection motion. This parallax motion can be further divided into two directions: vertically, uniform linear motion downward along the optical axis of the optical system; and horizontally, uniformly accelerated linear motion perpendicular to the optical axis with an initial velocity of zero. After exiting the beam gate, the electrons begin to transition to uniform linear motion.

[0111] In this embodiment, if Figure 11 As shown, the right-side second aperture is in its operating position. The electron beam enters the corresponding second beam gate through the mounting hole of the right-side second aperture. Assume the distance between the beam gate plates is d, the length of the upper portion 201 of the positive electrode is L1, the length of the blade portion of the lower portion 202 of the positive electrode is L2, and the deflection voltage between the plates is U. Point A on the lower portion 202 of the positive electrode is the near point where the electron beam is shut off, corresponding to the maximum deflection angle of the electron beam; point B is the far point where the electron beam is shut off, corresponding to the minimum deflection angle of the electron beam. The area between points A and B is the effective operating area of ​​the blade structure, receiving the bombardment of the shut-off electron beam.

[0112] The speed of electrons in the accelerating electric field is v0. According to the law of conservation of energy in the electric field, have to

[0113] In the deflection electric field inside the beam gate, the electrons move vertically downward along the optical axis of the optical system in a uniform linear motion, and move in a direction perpendicular to the optical axis and parallel to the magnetic field lines with a uniform acceleration of a. Therefore, the expression of the vertical displacement y is:

[0114] y=v0t (1)

[0115] The expression of the horizontal displacement x is:

[0116]

[0117] The expression of vertical component velocity is:

[0118] v y =v0 (3)

[0119] The expression of the horizontal component velocity is:

[0120] v x =at (4)

[0121] The expression of acceleration a is:

[0122]

[0123] Where x1 is the distance the electron beam deviates from the optical axis at the beam gate exit, x2 is the distance the electron deviates from the optical axis at the lower portion 202 of the positive electrode, and θ is the angle between the electron's motion direction and the downward direction of the optical axis at time t. Since this is a quasi-projectile motion, the intersection of the reverse extension of the electron's motion direction at time t and the optical axis must be at point M, the midpoint of the electron's displacement along the optical axis. Mathematical calculations show that at time t:

[0124]

[0125]

[0126]

[0127] The acceleration voltage U0 of the electron gun in the device is between 40kV and 100kV, with a typical value of 70kV. The deflection voltage applied to the beam gate plate is between 10V and 15V, with a typical value of 12V.

[0128] To ensure that the electron beam can be shut off normally when U0 and U are within the normal voltage range, and that the electron beam position is between points A and B after shutdown, x1 and x2 must at least meet the following conditions:

[0129]

[0130]

[0131] In this embodiment, the beam gate plate length L1 = 14.4 mm, the plate spacing d = 0.4 mm, and the length of the blade edge portion of the lower portion 202 of the positive electrode, L2 = 15.0 mm. Substituting these values ​​into the formula to calculate the values ​​of x1 and x2, it can be seen that when U varies within the range of 10 to 15 V, or when U0 varies between 40 kV and 100 kV, the electron beam passing through this device is effectively shut off between points A and B of the blade edge. This ensures that the shut-off electron beam does not strike the upper portion of the positive electrode 200 plate and prevents light leakage during shut-off, thus meeting operational requirements. In practical applications, the values ​​of x1 and x2 are calculated with a 5-10-fold redundancy to further ensure the reliability of the device.

[0132] In addition, the two apertures and the corresponding two beam gates are completely symmetrical in mechanical structure and electrical performance. Therefore, when the working aperture is switched to another path, the same design dimensions, calculation results and application effects are used to ensure that the electron beam can still be effectively shut off.

[0133] Step 9: If maintenance or replacement of the aperture blades is required during use, first disassemble the optical column of the semiconductor device to expose the device. Remove the control voltage signal cable and the second fixing bolt 800 before removing the device. Observe the two aperture blades in the aperture section under a microscope to identify and determine the damaged aperture. Remove the damaged aperture using tweezers and a small flat-head screwdriver. Place the two components, the bolt, and the washer 700 in anhydrous ethanol and sonicate for 15 minutes using an ultrasonic generator. Dry after sonication.

[0134] After replacing the new aperture, reassemble the aperture and beam gate components according to the same structure and order as when they were disassembled. Wipe the lower surface of the upper half of the light column and the upper surface of the lower half, and clean and inspect the seals. Use a vacuum cleaner and nitrogen gun to blow out the upper and lower parts of the light column, and finally reassemble the entire assembly.

[0135] Step 10: After turning on the device, follow the operating procedures and use the device's built-in software to further complete the overall calibration of the electronic optical system.

[0136] The present invention provides an integrated electron beam aperture and beam gate device. By positioning the aperture on the upper portion of the base, it can be installed in the optical path before the beam gate, facilitating beam gate control of the electron beam. The overall device is compact and compact. This compact design reduces the volume of the entire optical column, further reducing the overall device size and improving cleanroom utilization. The spacing between the positive and negative plates of the beam gate in the device is small, reducing the required beam gate control voltage, reducing the complexity of the beam gate control circuit, increasing the electron beam shutoff frequency, and improving device processing efficiency. The lower portion of the positive electrode utilizes a knife-edge groove structure, improving electron beam bombardment tolerance and reducing component maintenance cycles. The knife-edge flat structure shortens the travel distance during electron beam shutoff, effectively reducing beam tailing during shutdown. By providing two apertures with different apertures, switching between them is facilitated according to processing requirements, improving processing efficiency. The device comprises two apertures and two beam gates, forming two identical aperture and beam gate paths corresponding to each other, allowing for convenient switching between them as needed.

[0137] By modifying the design dimensions of the device of the present invention, it can adapt to different requirements of electronic optical systems, and has guiding and reference significance in the maintenance and modification of related equipment and instruments such as electron beam lithography machines and electron scanning microscopes, the development of new equipment and instruments, and related technical research.

[0138] An embodiment of the present application further provides an electron optical system, comprising an electron beam stop and beam gate integrated device as described in the above embodiment, wherein the electron beam stop and beam gate integrated device is installed after the second-stage lens of the electron optical system.

[0139] An embodiment of the present application also provides a semiconductor device comprising the above-mentioned electronic optical system.

[0140] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0141] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0142] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0143] In the embodiments provided in this application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely illustrative. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0144] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0145] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. An integrated electron beam stop and beam gate device, characterized in that: include: A base, a positive electrode, a first aperture blade, and a second aperture blade; The base is provided with a first negative plate and a second negative plate inside, and a first aperture piece mounting hole and a second aperture piece mounting hole on the top; The positive electrode is in the shape of an elongated strip, the upper portion of the positive electrode is engaged with the base, the first negative electrode plate and the second negative electrode plate are separated on both sides of the upper portion of the positive electrode, a first beam gate is formed between the first negative electrode plate and the positive electrode, and a second beam gate is formed between the second negative electrode plate and the positive electrode; a knife-edge groove structure is provided at the lower portion of the positive electrode; the knife-edge groove structure is a groove provided on both sides of the lower portion of the positive electrode, and a knife-edge plane structure is provided at the end of the groove, and the plane within the groove is at a preset distance from the outer plane of the upper portion of the positive electrode; The first aperture plate and the second aperture plate are respectively installed in the first aperture plate installation hole and the second aperture plate installation hole; the first aperture plate is located above the first beam gate, and the second aperture plate is located above the second beam gate.

2. The electron beam stop and beam gate integrated device according to claim 1, wherein: The base comprises: a cylindrical hollow structure and a mounting seat; A first groove and a second groove are provided inside the cylindrical hollow structure. The central axis of the first groove coincides with the central axis of the second groove, and the width of the first groove is smaller than the width of the second groove. The first negative electrode plate and the second negative electrode plate are two side walls of the first groove. When the positive electrode is mated with the base, it is located between the first negative electrode plate and the second negative electrode plate. The first aperture piece mounting hole and the second aperture piece mounting hole are located at the top of the cylindrical hollow structure and are respectively arranged on both sides of the central axis; The mounting seat is arranged on one side of the cylindrical hollow structure, and the lower surface thereof is flush with the lower surface of the cylindrical hollow structure; A positive electrode mounting hole is provided on the bottom surface of the first groove, and a first fixing bolt passes through the positive electrode mounting hole to fix the positive electrode on the base; The mounting seat is provided with a base mounting hole, and a second fixing bolt passes through the base mounting hole to fix the base on a mechanism or device connected to the diaphragm.

3. The electron beam stop and beam gate integrated device according to claim 2, wherein: The upper portion of the positive electrode is provided with two threaded holes that cooperate with the first fixing bolts; The lower portion of the positive electrode is located below the base.

4. The electron beam stop and beam gate integrated device according to claim 3, wherein: The lower portion of the positive electrode is in an inverted T shape and connected to the upper portion of the positive electrode, and the connection between the upper portion of the positive electrode and the lower portion of the positive electrode is configured in an arc shape.

5. The electron beam stop and beam gate integrated device according to claim 1, wherein: The distance between the two side walls of the upper part of the positive electrode and the first negative plate and the second negative plate is no more than 1 mm; after power is applied, the two side walls of the upper part of the positive electrode form two uniform electrostatic fields with the first negative plate and the second negative plate.

6. The electron beam stop and beam gate integrated device according to claim 3, wherein: The device also includes: two insulating positioning posts and two washers; The insulating positioning column and the washer cooperate with the corresponding positive electrode mounting hole and the corresponding first fixing bolt to connect the base and the positive electrode; The insulating positioning column is opposite to the positive electrode mounting hole and is located outside the base; the gasket is located between the positive electrode and the base.

7. The electron beam stop and beam gate integrated device according to claim 6, wherein: The insulating positioning column and the washer are made of ceramic material.

8. The electron beam stop and beam gate integrated device according to claim 1, wherein: The aperture of the first light hole on the first aperture plate is different from the aperture of the second light hole on the second aperture plate.

9. The electron beam stop and beam gate integrated device according to claim 2, wherein: The base mounting hole cooperates with the second fixing bolt to fix the base on the fine-tuning mechanism; the fine-tuning mechanism selects different aperture pieces by controlling the position and rotation angle of the base, and controls the position of the center of the aperture hole; the aperture pieces include the first aperture piece and the second aperture piece.

10. An electron optical system, characterized in that The invention comprises the electron beam stop and beam gate integrated device according to any one of claims 1 to 8, wherein the electron beam stop and beam gate integrated device is installed after the second-stage lens of the electron optical system.

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