Charged particle beam device

Abstract

The utility model discloses a kind of charged particle beam devices, it includes: main chamber, mobile platform is equipped inside, the moving track of mobile platform includes wafer loading position;Electrostatic chuck, it is set on the mobile platform, for carrying wafer;Vacuum ultraviolet light source, it is set on the side wall of the main chamber, for providing vacuum ultraviolet light in the main chamber;Wherein, the vacuum ultraviolet light propagates in the direction towards the wafer loading position, to irradiate the electrostatic chuck moved to the wafer loading position.The vacuum ultraviolet light source of the utility model emits vacuum ultraviolet light, and the upper surface of electrostatic chuck moved to wafer loading position can be covered, and using wafer transmission in and out gap carries out electrostatic elimination processing, effectively improve the efficiency of electrostatic elimination and increase equipment throughput.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor detection, and in particular to a charged particle beam device. Background Technology

[0002] In the semiconductor manufacturing field, charged particle beam devices such as scanning electron microscopes (SEM) are widely used for measuring wafer surface patterns and detecting defects. To achieve high-precision wafer positioning and fixation, charged particle beam devices are typically equipped with electrostatic chucks (ESCs), which use electrostatic force to attract the wafer to their surface. However, due to factors such as contact and friction between the wafer and the ESC, residual electrostatic charge can easily accumulate on the ESC surface, causing the chuck's bearing surface to become charged, which in turn affects the normal operation of the charged particle beam device.

[0003] Currently, to eliminate residual electrostatic charges accumulated on the surface of an electrostatic chuck, a vacuum ultraviolet (VUV) light source is typically used to irradiate the surface of the chuck, thereby eliminating the accumulated residual electrostatic charges and preventing residual electrostatic forces from affecting the wafer. However, existing methods suffer from low efficiency in eliminating static electricity.

[0004] The statements herein provide only background information relating to this invention and do not necessarily constitute prior art. Utility Model Content

[0005] The purpose of this invention is to provide a charged particle beam device so that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source can cover the entire upper surface of the electrostatic chuck located at the wafer loading position, thereby improving the efficiency of static electricity elimination and the throughput of the equipment.

[0006] To achieve the above objectives, this utility model provides a charged particle beam device, comprising: a main chamber with a movable stage inside, the moving trajectory of which includes a wafer loading position; an electrostatic chuck disposed on the movable stage for carrying the wafer; and a vacuum extreme ultraviolet light source disposed on the side wall of the main chamber for providing vacuum extreme ultraviolet light into the main chamber; wherein the vacuum extreme ultraviolet light propagates in a direction toward the wafer loading position to irradiate the electrostatic chuck that has moved to the wafer loading position.

[0007] For example, the distance between the vacuum extreme ultraviolet light source and the wafer loading position is greater than or equal to a preset distance, so that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source can cover the entire upper surface of the electrostatic chuck.

[0008] For example, the vacuum extreme ultraviolet light source is positioned on a sidewall away from the wafer loading location.

[0009] For example, the charged particle beam device further includes a light-shielding device disposed at the light outlet of the vacuum extreme ultraviolet light source for blocking or exposing the vacuum extreme ultraviolet light source.

[0010] For example, the light-shielding device includes a light-shielding element and a driving element, the driving element being connected to the light-shielding element, the driving element being used to drive the light-shielding element to switch between a first position and a second position; when the light-shielding element is in the first position, it blocks the vacuum extreme ultraviolet light source; when the light-shielding element is in the second position, it exposes the vacuum extreme ultraviolet light source.

[0011] For example, the vacuum extreme ultraviolet light source is located inside or outside the main chamber, and the light outlet of the vacuum extreme ultraviolet light source faces the wafer loading position.

[0012] For example, when the vacuum extreme ultraviolet light source is located outside the main chamber, a light-transmitting structure is provided on the side wall of the main chamber, and the light outlet of the vacuum extreme ultraviolet light source is opposite to the light-transmitting structure.

[0013] For example, the electrostatic chuck is provided with a push pin for lifting the wafer; a detection device is provided below the electrostatic chuck for determining whether there is electrostatic charge on the electrostatic chuck.

[0014] For example, the detection device is a force sensor connected to the ejector pin. When the wafer is lifted to a preset height by the ejector pin, the force of the ejector pin lifting the wafer is measured to determine whether there is static charge on the electrostatic chuck.

[0015] For example, the detection device is a current sensor; the charged particle beam device also includes a motor for driving the lifting and lowering of the ejector pin, the motor being connected to the current sensor. When the wafer is lifted to a preset height by the ejector pin, the input current of the motor is measured to determine whether there is electrostatic charge on the electrostatic chuck.

[0016] For example, the detection device is a capacitance sensor. When the wafer is lifted to a preset height by the ejector pin, the capacitance between the lifted wafer and the electrostatic chuck is measured to determine whether there is electrostatic charge on the electrostatic chuck.

[0017] For example, the preset height to which the wafer is lifted by the ejector pin does not exceed 1 mm.

[0018] For example, the charged particle beam device also includes a control device connected to the vacuum extreme ultraviolet light source. When the current wafer is being transferred out of the main chamber and the next wafer has not been transferred into the main chamber, the control device controls the vacuum extreme ultraviolet light source to turn on and irradiate the electrostatic chuck located at the wafer loading position.

[0019] For example, the control device is also connected to the detection device and the drive unit respectively. When the number of wafers sent out of the main chamber reaches a set number or the amount of static charge on the electrostatic chuck exceeds a preset threshold, the control device controls the drive unit to drive the light-shielding member to switch to the second position at least once.

[0020] For example, the set quantity ranges from 1 piece to 300 pieces.

[0021] For example, the charged particle beam device further includes a conveying device disposed outside the main chamber for picking up and placing the wafer at the wafer loading position.

[0022] For example, the charged particle beam device further includes a drive device connected to the ejector pin for driving the ejector pin to move up and down.

[0023] For example, the charged particle beam device further includes a rotating device disposed below the electrostatic chuck and connected to the electrostatic chuck to drive the electrostatic chuck to rotate.

[0024] Compared with the prior art, the technical solution of this utility model has at least the following beneficial effects:

[0025] The charged particle beam device provided by this invention improves the efficiency of static electricity elimination by placing a vacuum extreme ultraviolet light source on the side wall of the main chamber and emitting vacuum extreme ultraviolet light towards the wafer loading position. This allows the vacuum extreme ultraviolet light to cover the upper surface of the electrostatic chuck that has moved to the wafer loading position. Simultaneously, by setting the static electricity elimination position of the electrostatic chuck at the wafer loading position, no additional movement of the electrostatic chuck is required during static electricity elimination, reducing the number of times the electrostatic chuck is moved. Furthermore, static electricity elimination can be performed using the gap between wafer infeed and outfeed, effectively improving the efficiency of static electricity elimination and increasing equipment throughput.

[0026] Furthermore, by placing the vacuum extreme ultraviolet light source on a sidewall far from the wafer loading position or on a sidewall at a distance greater than or equal to a preset distance, the present invention provides a larger irradiation area of ​​the vacuum extreme ultraviolet light source, which can cover the entire upper surface of the electrostatic chuck with a single irradiation, thereby improving the efficiency and uniformity of static elimination.

[0027] Furthermore, this invention provides a light-shielding device at the light outlet of the vacuum extreme ultraviolet light source, enabling rapid blocking or exposure of the source. This allows the vacuum extreme ultraviolet light source to be shielded without being turned off during continuous alternating detection and static elimination processes. This reduces the frequent switching and preheating time required for the vacuum extreme ultraviolet light source, improves the efficiency of static elimination, and extends the lifespan of the vacuum extreme ultraviolet light source.

[0028] Furthermore, by setting a detection device below the electrostatic chuck, the present invention can detect the amount of residual static charge on the electrostatic chuck in a timely manner. The control device controls the opening of the vacuum extreme ultraviolet light source or the light shielding device according to the amount of static charge, so that the vacuum extreme ultraviolet light irradiates the electrostatic chuck to eliminate the static charge, effectively avoiding the accumulation of excessive residual charge on the electrostatic chuck and thus avoiding the impact on wafer inspection. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the charged particle beam device of this utility model;

[0030] Figure 2 This is a side view of the charged particle beam device of this utility model;

[0031] Figure 3 This is a schematic diagram of the switch for the vacuum extreme ultraviolet light source in the charged particle beam device of this utility model;

[0032] Figure 4 This is a schematic diagram of a charged particle beam device according to an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of a charged particle beam device according to another embodiment of the present invention;

[0034] Figure 6 This is a schematic diagram of a charged particle beam device according to another embodiment of the present invention;

[0035] Figure 7 This is a flowchart of the method for removing residual electrostatic charge in the charged particle beam device of this invention. Detailed Implementation

[0036] The charged particle beam device proposed in this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this utility model will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, only for the purpose of conveniently and clearly illustrating the embodiments of this utility model. Please refer to the drawings to make the objectives, features, and advantages of this utility model more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0037] Research has found that due to factors such as contact and friction between the wafer and the electrostatic chuck, residual electrostatic charge easily accumulates on the surface of the electrostatic chuck in charged particle beam devices, thus affecting the normal operation of the device. Therefore, to reduce the impact of residual electrostatic charge on the charged particle beam device, it is necessary to periodically remove the accumulated residual electrostatic charge on the electrostatic chuck. In practical applications, a vacuum extreme ultraviolet (VUV) light source can be used to irradiate the surface of the electrostatic chuck, neutralizing the residual electrostatic charge through the photoelectric effect or gas ionization, thereby achieving electrostatic elimination. However, this method has the following drawbacks: 1. Because the electrostatic chuck needs frequent electrostatic elimination, the VUV light source also needs to be frequently switched on and off. The preheating time for each VUV light source switch is long, reducing the throughput of the charged particle beam device; 2. The VUV light emitted by the VUV light source cannot completely cover the entire upper surface of the electrostatic chuck. Moving the light source or the electrostatic chuck is required to eliminate the electrostatic charge on the entire upper surface, resulting in a long time required to eliminate residual electrostatic charge and low efficiency in electrostatic elimination.

[0038] To address the aforementioned shortcomings, this utility model provides a charged particle beam device 100 (see [link to utility model]). Figure 1 The charged particle beam device 100 uses a vacuum extreme ultraviolet (EUV) light source 102 mounted on the side wall 111 of the main chamber 101. The UV light source 102 emits UV light towards the wafer loading position 112, allowing the UV light to cover the entire upper surface of the electrostatic chuck 103 that has moved to the wafer loading position 112, thereby improving the static elimination effect and reducing the required static elimination time. Furthermore, by setting the static elimination position of the electrostatic chuck 103 at the wafer loading position 112, the number of times the electrostatic chuck 103 moves is reduced, and static elimination is performed using the wafer infeed / outfeed gap, effectively improving the efficiency of static elimination and increasing equipment throughput.

[0039] Specifically, such as Figure 1 As shown, this utility model discloses a charged particle beam device 100, which includes: a main chamber 101, inside which is a movable stage (not shown), the moving trajectory of which includes a wafer loading position 112 and a wafer observation position 113; an electrostatic chuck 103, which is disposed on the movable stage and used to carry the wafer, the movable stage can drive the electrostatic chuck 103 to move from the wafer observation position 113 to the wafer loading position 112; and a conveying device 104, which is disposed outside the main chamber 101 and used to pick up the wafer at the wafer loading position 112. The wafer is placed in the main chamber 101; a vacuum extreme ultraviolet light source 102 is disposed on the side wall 111 of the main chamber 101 to provide vacuum extreme ultraviolet light into the main chamber 101; wherein, the vacuum extreme ultraviolet light propagates in a direction toward the wafer loading position 112 to irradiate the electrostatic chuck 103 that has moved to the wafer loading position 112. By setting the electrostatic elimination position at the wafer loading position 112, not only are the number of movements of the electrostatic chuck 103 reduced, but the electrostatic elimination process can also be carried out using the gap between wafer ingress and egress, effectively improving the efficiency of electrostatic elimination and increasing the throughput of the equipment. It is understood that, as Figure 2 As shown, the height of the vacuum extreme ultraviolet light source 102 on the side wall 111 is higher than the height of the upper surface of the electrostatic chuck 103, so as to ensure that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 illuminates the upper surface of the electrostatic chuck 103.

[0040] Furthermore, to ensure that the illumination area of ​​the vacuum extreme ultraviolet light provided by the vacuum extreme ultraviolet light source 102 can meet the requirement of uniformly eliminating static electricity, such as... Figure 1 As shown, the vacuum extreme ultraviolet light source 102 is disposed on the sidewall away from the wafer loading position 112. In this embodiment, the main chamber 101 includes two long sidewalls 111a and 111b and two short sidewalls 111c and 111d. The wafer loading position 112 is located at the corner where the long sidewalls 111a and 111d intersect. The vacuum extreme ultraviolet light source 102 is disposed on the long sidewall 111b away from the wafer loading position 112 to make the illumination area of ​​the vacuum extreme ultraviolet light source 102 larger. By disposing of the vacuum extreme ultraviolet light source 102 on the sidewall away from the wafer loading position 112, it is possible not only to ensure that the illumination area of ​​the vacuum extreme ultraviolet light can cover the entire upper surface of the electrostatic chuck 103, thereby achieving all-round static elimination of the electrostatic chuck 103, but also to ensure the efficiency and uniformity of static elimination of the electrostatic chuck 103.

[0041] In other embodiments, the distance between the vacuum extreme ultraviolet light source 102 and the wafer loading position 112 is greater than or equal to a preset distance, so that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 can cover the entire upper surface of the electrostatic chuck 103, thereby achieving uniform irradiation of the electrostatic chuck 103 by the vacuum extreme ultraviolet light, reducing the blind zone for static elimination, and ensuring the uniformity of static elimination on the electrostatic chuck 103. This eliminates residual static charge accumulated on the electrostatic chuck 103, thereby avoiding process problems such as wafer warpage, breakage, or positioning errors caused by residual static charge. For example, the preset distance ranges from 500mm to 1000mm. In some embodiments, the preset distance is 500mm, 600mm, 900mm, or 1000mm. When the distance between the vacuum extreme ultraviolet light source 102 and the wafer loading position 112 is any of the above preset distances, the vacuum extreme ultraviolet light source 102 can achieve a better static elimination effect.

[0042] To further improve the uniformity of static electricity elimination in the vacuum extreme ultraviolet light source 102, such as Figure 4 and Figure 5 As shown, the charged particle beam device 100 also includes a rotating device 108, which is disposed below the electrostatic chuck 103 and connected to the electrostatic chuck 103 to drive the electrostatic chuck 103 to rotate. In practical applications, when eliminating static electricity from the electrostatic chuck 103, the vacuum extreme ultraviolet light provided by the vacuum extreme ultraviolet light source 102 propagates along the direction toward the wafer loading position 112 and irradiates the surface of the electrostatic chuck 103. At the same time, the electrostatic chuck 103 rotates under the drive of the rotating device 108, so that the upper surface of the electrostatic chuck 103 is completely covered and irradiated by the vacuum extreme ultraviolet light, reducing the irradiation dead zone of the vacuum extreme ultraviolet light, thereby improving the effect and uniformity of eliminating static electricity.

[0043] Furthermore, such as Figure 1 and Figure 2 As shown, the vacuum extreme ultraviolet light source 102 can be disposed inside or outside the main chamber 101, with the light outlet 121 of the vacuum extreme ultraviolet light source 102 facing the wafer loading position 112. When the vacuum extreme ultraviolet light source 102 is disposed inside the main chamber 101, the vacuum extreme ultraviolet light can directly irradiate the electrostatic chuck 103, shortening the optical transmission path of the vacuum extreme ultraviolet light in the vacuum environment. This reduces window absorption and scattering losses of the vacuum extreme ultraviolet light, enhances the light intensity utilization rate, and thus effectively improves the static electricity elimination effect.

[0044] In this embodiment, as Figure 1As shown, the vacuum extreme ultraviolet light source 102 is disposed outside the main chamber 101. A light-transmitting structure is provided on the side wall of the main chamber 101. The light-emitting port 121 of the vacuum extreme ultraviolet light source 102 is opposite to the light-transmitting structure. The vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 is transmitted to the main chamber 101 through the light-transmitting structure and propagates in a direction toward the wafer loading position 112, thereby illuminating the electrostatic chuck 103 located at the wafer loading position 112. For example, the light-transmitting structure includes a light-transmitting window located on the side wall 111 of the main chamber 101. A corresponding lens is provided inside the light-transmitting window to allow the vacuum extreme ultraviolet light to enter the main chamber 101 through the lens. By placing the vacuum extreme ultraviolet light source 102 outside the main chamber 101, not only can the space inside the main chamber 101 be saved, but the interference caused by the heat generated by the vacuum extreme ultraviolet light source 102 to other components (such as electron guns, detectors, etc.) in the vacuum environment inside the main chamber 101 can also be reduced.

[0045] Furthermore, after the static electricity elimination process, the vacuum extreme ultraviolet light source 102 needs to be turned off to prevent the extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 from affecting the wafer inspection process. Therefore, the vacuum extreme ultraviolet light source 102 needs to be turned on again before the next static electricity elimination process. However, the vacuum extreme ultraviolet light source 102 needs to be preheated before it can work normally, and this preheating process is time-consuming, which will seriously affect the production cycle when continuous inspection and static electricity elimination are performed. Based on the above, in order to avoid the decrease in static electricity elimination efficiency caused by the frequent switching of the vacuum extreme ultraviolet light source 102, such as... Figure 3 As shown, a light-shielding device 122 is provided at the light outlet 121 of the vacuum extreme ultraviolet light source 102. The light-shielding device 122 is used to block or expose the vacuum extreme ultraviolet light source 102, thereby realizing that when the detection process and the static electricity elimination process are continuously and alternately performed, there is no need to frequently switch the vacuum extreme ultraviolet light source 102 on and off, reducing the preheating time required for frequent switching of the vacuum extreme ultraviolet light source 102, improving the efficiency of static electricity elimination, and extending the service life of the vacuum extreme ultraviolet light source 102.

[0046] For example, the light-shielding device 122 includes a light-shielding member 1221 and a driving member (not shown in the figure). The driving member is connected to the light-shielding member 1221 and is used to drive the light-shielding member 1221 to switch between a first position and a second position. Further, as... Figure 3 As shown, Figure 3Figures (a) and (b) are schematic diagrams of the light-shielding member 1221 in the first and second positions of this embodiment, respectively. When the light-shielding member 1221 is in the first position, it blocks the vacuum extreme ultraviolet light source 102, allowing the wafer inspection process to be performed in the main chamber 101. When the light-shielding member 1221 is in the second position, it exposes the vacuum extreme ultraviolet light source 102, and the emitted vacuum extreme ultraviolet light irradiates the electrostatic chuck 103 located at the wafer loading position 112, eliminating the electrostatic charge on the surface of the electrostatic chuck 103. As an optional embodiment, the light-shielding member 1221 is a shielding plate, and the driving member is a linear motor to drive the shielding plate to move along a straight line from the first position to the second position or from the second position to the first position.

[0047] Since the vacuum extreme ultraviolet light source 102 is only needed to provide vacuum extreme ultraviolet light to eliminate static electricity when residual static charge exists on the surface of the electrostatic chuck, the charged particle beam device 100 provided by this invention also provides various detection devices to measure the static charge on the electrostatic chuck 103. For example... Figures 4-6 As shown, the electrostatic chuck 103 is equipped with a push pin 131, which is used to lift the wafer W. A detection device is provided below the electrostatic chuck 103 to determine whether there is electrostatic charge on the electrostatic chuck 103. If there is residual electrostatic charge on the electrostatic chuck 103, the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 can dissociate the gas and neutralize the electrostatic charge under vacuum. When the electrostatic chuck 103 moves to the wafer loading position 112, and the current wafer W is transferred out of the main chamber 101 by the transfer device 104 and the next wafer has not been transferred into the main chamber 101, the vacuum extreme ultraviolet light source 102 is turned on or the shielding member 1221 that blocks the vacuum extreme ultraviolet light source 102 is turned on, so that the vacuum extreme ultraviolet light irradiates the surface of the electrostatic chuck 103 to eliminate the residual electrostatic charge on the surface of the electrostatic chuck 103.

[0048] In one embodiment, such as Figure 4As shown, a driving device 106 is provided below the ejector pin 131. The driving device 106 is connected to the ejector pin 131 and is used to drive the ejector pin 131 to rise and fall. The driving device 106 is a cylinder to drive the ejector pin 131 to move vertically. In this embodiment, the detection device 171 is located between the driving device 106 and the ejector pin 131, and the detection device 171 is a force sensor. The force sensor is connected to the ejector pin 131. When the wafer W is lifted to a preset height by the ejector pin 131, the force sensor measures the supporting force of the ejector pin 131 lifting the wafer W to determine whether there is electrostatic charge on the electrostatic chuck 103. Specifically, by comparing with the reference supporting force when there is no electrostatic charge on the electrostatic chuck 103, if the supporting force of the ejector pin lifting the wafer W measured by the force sensor is greater than the reference supporting force, it is determined that there is electrostatic charge on the electrostatic chuck 103.

[0049] In another embodiment, such as Figure 5 As shown, the driving device 106 located below the ejector pin 131 is a motor used to drive the ejector pin 131 to rise and fall. In this embodiment, the detection device 172 is a current sensor connected to the motor. When the wafer W is lifted to a preset height by the ejector pin 131, the input current of the motor is measured to determine whether there is electrostatic charge on the electrostatic chuck 103. Specifically, by comparing the current with the reference current input when the motor drives the ejector pin 131 to rise and fall when there is no electrostatic charge on the electrostatic chuck 103, if the current sensor measures that the input current of the motor is greater than the reference current, it is determined that there is electrostatic charge on the electrostatic chuck 103.

[0050] In yet another embodiment, such as Figure 6As shown, the detection device 173 is a capacitance sensor, which is electrically connected to the electrostatic chuck 103. When the wafer W is lifted to a preset height by the ejector pin 131, the capacitance between the lifted wafer W and the electrostatic chuck 103 is measured to determine whether there is electrostatic charge on the electrostatic chuck 103. Specifically, if there is no electrostatic charge on the electrostatic chuck 103, the wafer W is lifted by the ejector pin 131 and completely leaves the surface of the electrostatic chuck 103. The distance d between the lower surface of the wafer W and the upper surface of the electrostatic chuck 103 is large. At this time, the capacitance measured by the capacitance sensor between the lifted wafer W and the electrostatic chuck 103 is small. If there is electrostatic charge on the electrostatic chuck 103, when the wafer W is lifted by the ejector pin 131, part of the wafer W does not leave the surface of the electrostatic chuck 103, that is, part of the lower surface of the wafer W (e.g., The wafer edge is in contact with the upper surface of the electrostatic chuck 103. The distance d between the lower surface of the wafer W and the upper surface of the electrostatic chuck 103 is small. At this time, the capacitance sensor measures that the capacitance between the lifted wafer W and the electrostatic chuck 103 is large. By comparing the capacitance between the wafer W and the electrostatic chuck 103, it is possible to determine whether there is electrostatic charge on the electrostatic chuck 103. If the capacitance between the wafer W and the electrostatic chuck is large, it is determined that there is electrostatic charge on the electrostatic chuck 103.

[0051] For example, in any of the above embodiments, the preset height at which the wafer W is lifted by the ejector pin 131 does not exceed 1 mm. Within this preset height range, after the wafer W is lifted by the ejector pin 131, due to the electrostatic force provided by the electrostatic chuck 103, the wafer W will slightly arch, and its cross-section will form a convex shape with a high center and low edges. The distance between the highest point of the center of the lower surface of the wafer W and the upper surface of the electrostatic chuck 103 does not exceed 1 mm, which can effectively prevent the wafer W from breaking.

[0052] like Figure 1 As shown, in one embodiment, the charged particle beam device 100 further includes a control device 105 connected to the vacuum extreme ultraviolet light source 102. When the current wafer W is transferred out of the main chamber 101 and the next wafer W is not transferred into the main chamber 102, the control device 105 controls the vacuum extreme ultraviolet light source 102 to turn on. The vacuum extreme ultraviolet light provided by the vacuum extreme ultraviolet light source 102 is emitted from the light outlet 121 and irradiates the electrostatic chuck 103 located at the wafer loading position 112, thereby realizing the elimination of static electricity from the electrostatic chuck 103.

[0053] Furthermore, such as Figures 1-4As shown, the control device 105 is also connected to the detection device and the driving component respectively. When the number of wafers W being transferred out of the main chamber 101 reaches a set number or the amount of static charge on the electrostatic chuck 103 exceeds a preset threshold, the control device 105 controls the driving component to drive the light-shielding component 1221 to switch to the second position at least once, that is, to open the light-shielding component 1221 and expose the vacuum extreme ultraviolet light source 102, so that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source 102 irradiates the electrostatic chuck 103 located at the wafer loading position 112. The set quantity ranges from 1 to 300 wafers. When the set quantity is 1 wafer, the electrostatic chuck 103 is subjected to vacuum extreme ultraviolet light irradiation after each wafer W is transferred out of the main chamber 101 to remove any residual electrostatic charge. When the set quantity is 300 wafers, the electrostatic chuck 103 is subjected to vacuum extreme ultraviolet light irradiation only after every 300 wafers W are transferred to the main chamber 101, i.e., a static electricity elimination process is performed. The specific set quantity is determined based on the actual testing conditions, and this utility model does not limit it.

[0054] It is understood that the preset threshold for the amount of electrostatic charge can be set based on experience, or the presence or absence of electrostatic charge can be determined based on the magnitude of the supporting force of the ejector pin lifting the wafer measured by a force sensor, the magnitude of the input current of the measuring motor measured by a current sensor, or the magnitude of the capacitance between the wafer and the electrostatic chuck measured by a capacitance sensor. When these measured values ​​are greater than the corresponding threshold (e.g., reference supporting force, reference current, etc.), it can also be considered that the amount of electrostatic charge on the electrostatic chuck exceeds the preset threshold. This utility model does not limit this.

[0055] Accordingly, when performing static electricity elimination processing based on the charged particle beam device 100 provided by this utility model, such as Figure 7 As shown, the specific steps include the following:

[0056] S1. When the nth wafer W is inspected, the electrostatic chuck 103 is moved to the wafer loading position 112, where n is a positive integer;

[0057] S2. The detection device measures the amount of static charge on the electrostatic chuck 103;

[0058] S3. Determine whether the static charge of the electrostatic chuck 103 exceeds a preset threshold; if it does, proceed to S4; if it does not, proceed to step S5.

[0059] S4. Perform the static electricity elimination process; the static electricity elimination process includes:

[0060] S41. Determine whether the vacuum extreme ultraviolet light source 102 is in the start-up state and whether the light-shielding member 1221 is in the first position; if the vacuum extreme ultraviolet light source 102 is in the start-up state and the light-shielding member 1221 is in the first position, then execute S411 to S413; otherwise, execute S421 to S424.

[0061] S411, the conveying device 104 takes out the current wafer W, switches the light shielding component 1221 to the second position, and the vacuum extreme ultraviolet light source 102 provides vacuum extreme ultraviolet light to irradiate the electrostatic chuck 103.

[0062] S412, the light-shielding component 1221 is switched to the first position, the conveying device 104 introduces the m-th wafer, and performs a detection process on the m-th wafer; m = n + i, i is the number of detections;

[0063] S413. After the m-th wafer is inspected, move the electrostatic chuck 103 to the wafer loading position 112 and repeat steps S2 to S4.

[0064] The specific steps of S421 to S424 are as follows:

[0065] S421. Start the vacuum extreme ultraviolet light source 102 and switch the light shield 1221 to the first position;

[0066] S422, the conveying device 104 takes out the current wafer W, switches the light-shielding 1221 to the second position, and the vacuum extreme ultraviolet light source 102 provides vacuum extreme ultraviolet light to irradiate the electrostatic chuck 103.

[0067] S423, the light-shielding component 1221 is switched to the first position, the conveying device 104 introduces the m-th wafer, and performs a detection process on the m-th wafer, where m = n + i, and i is the number of detections;

[0068] S424. After the m-th wafer is inspected, move the electrostatic chuck 103 to the wafer loading position 112 and repeat steps S2 to S4.

[0069] Step S5 includes: determining whether to continue the wafer inspection process; if the wafer inspection process continues, then step S424 is executed, and steps S2 to S4 are repeated; if the wafer inspection process ends, then the vacuum extreme ultraviolet light source is turned off.

[0070] In summary, the charged particle beam device 100 of this utility model improves the efficiency of static elimination by placing a vacuum extreme ultraviolet light source 102 on the side wall 111 of the main chamber 101 and emitting vacuum extreme ultraviolet light towards the wafer loading position 112. This allows the vacuum extreme ultraviolet light to cover the upper surface of the electrostatic chuck 103 that has moved to the wafer loading position 112. At the same time, setting the static elimination position of the electrostatic chuck 103 at the wafer loading position 112 reduces the number of times the electrostatic chuck 103 moves and utilizes the gap between wafer infeed and outfeed for static elimination, effectively improving the efficiency of static elimination and increasing the throughput of the equipment.

[0071] Furthermore, by setting the vacuum extreme ultraviolet light source 102 on the sidewall 111 away from the wafer loading position 112 or on the sidewall 111 at a distance greater than or equal to a preset distance, the present invention makes the irradiation area of ​​the vacuum extreme ultraviolet light source 102 larger, and can cover the entire upper surface of the electrostatic chuck 103 with one irradiation, thereby improving the efficiency and uniformity of static elimination.

[0072] Furthermore, by providing a light-shielding device 122 at the light outlet 121 of the vacuum extreme ultraviolet light source 102, this utility model enables rapid shielding or exposure of the vacuum extreme ultraviolet light source. Consequently, during the continuous alternating execution of the detection process and the static electricity elimination process, it is not necessary to turn off the vacuum extreme ultraviolet light source 102. The light-shielding device 122 can also shield the vacuum extreme ultraviolet light source 102, reducing the preheating time required for frequent switching of the vacuum extreme ultraviolet light source 102, improving the efficiency of static electricity elimination, and extending the service life of the vacuum extreme ultraviolet light source 102.

[0073] Furthermore, by setting a detection device below the electrostatic chuck 103, the present invention can detect the amount of residual static charge on the electrostatic chuck 103 in a timely manner. The control device controls the opening of the vacuum extreme ultraviolet light source 102 or the light shielding device 122 according to the amount of static charge, so that the vacuum extreme ultraviolet light irradiates the electrostatic chuck 103 to eliminate the static charge, effectively avoiding the accumulation of excessive residual charge on the electrostatic chuck 103, which would affect wafer inspection.

[0074] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0075] In the description of this utility model, it should be understood that the terms "center," "height," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0076] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0077] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0078] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above content. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A charged particle beam device, characterized in that, include: The main chamber contains a movable stage, the movement trajectory of which includes the wafer loading position; An electrostatic chuck, which is disposed on the moving stage, is used to carry the wafer; A vacuum extreme ultraviolet light source is disposed on the side wall of the main chamber and is used to provide vacuum extreme ultraviolet light into the main chamber; The vacuum extreme ultraviolet light propagates in a direction toward the wafer loading position to irradiate the electrostatic chuck that has moved to the wafer loading position.

2. The charged particle beam device as described in claim 1, characterized in that, The distance between the vacuum extreme ultraviolet light source and the wafer loading position is greater than or equal to a preset distance, so that the vacuum extreme ultraviolet light emitted by the vacuum extreme ultraviolet light source can cover the entire upper surface of the electrostatic chuck.

3. The charged particle beam device as described in claim 1, characterized in that, The vacuum extreme ultraviolet light source is located on the sidewall away from the wafer loading position.

4. The charged particle beam device as described in claim 1, characterized in that, Also includes: A light-shielding device is installed at the light outlet of the vacuum extreme ultraviolet light source to block or expose the vacuum extreme ultraviolet light source.

5. The charged particle beam device as described in claim 4, characterized in that, The light-shielding device includes a light-shielding component and a driving component. The driving component is connected to the light-shielding component and is used to drive the light-shielding component to switch between a first position and a second position. When the light-shielding component is in the first position, it blocks the vacuum extreme ultraviolet light source. When the light-shielding component is in the second position, it exposes the vacuum extreme ultraviolet light source.

6. The charged particle beam device as claimed in claim 1, characterized in that, The vacuum extreme ultraviolet light source is located inside or outside the main chamber, with the light outlet of the vacuum extreme ultraviolet light source facing the wafer loading position.

7. The charged particle beam device as described in claim 6, characterized in that, When the vacuum extreme ultraviolet light source is located outside the main chamber, a light-transmitting structure is provided on the side wall of the main chamber, and the light outlet of the vacuum extreme ultraviolet light source is opposite to the light-transmitting structure.

8. The charged particle beam device as claimed in claim 1, characterized in that, The electrostatic chuck is equipped with a push pin for lifting the wafer; a detection device is located below the electrostatic chuck for determining whether there is electrostatic charge on the electrostatic chuck.

9. The charged particle beam device as described in claim 8, characterized in that, The detection device is a force sensor connected to the ejector pin. When the wafer is lifted to a preset height by the ejector pin, the force of the ejector pin lifting the wafer is measured to determine whether there is static charge on the electrostatic chuck.

10. The charged particle beam device as claimed in claim 8, characterized in that, The detection device is a current sensor; the charged particle beam device also includes a motor for driving the lifting and lowering of the ejector pin. The motor is connected to the current sensor. When the wafer is lifted to a preset height by the ejector pin, the input current of the motor is measured to determine whether there is electrostatic charge on the electrostatic chuck.

11. The charged particle beam device as claimed in claim 8, characterized in that, The detection device is a capacitance sensor. When the wafer is lifted to a preset height by the ejector pin, the capacitance between the lifted wafer and the electrostatic chuck is measured to determine whether there is electrostatic charge on the electrostatic chuck.

12. The charged particle beam device according to any one of claims 9 to 11, characterized in that, The preset height at which the wafer is lifted by the ejector pin does not exceed 1 mm.

13. The charged particle beam device as described in claim 1 or 5, characterized in that, It also includes a control device connected to the vacuum extreme ultraviolet light source. When the current wafer is transferred out of the main chamber and the next wafer has not been transferred into the main chamber, the control device controls the vacuum extreme ultraviolet light source to turn on and irradiate the electrostatic chuck located at the wafer loading position.

14. The charged particle beam device as claimed in claim 13, characterized in that, The control device is also connected to the detection device and the driving component. When the number of wafers sent out of the main chamber reaches a set number or the amount of static charge on the electrostatic chuck exceeds a preset threshold, the control device controls the driving component to drive the light-shielding component to switch to the second position at least once.

15. The charged particle beam device as claimed in claim 14, characterized in that, The set quantity ranges from 1 piece to 300 pieces.

16. The charged particle beam device as claimed in claim 1, characterized in that, Also includes: A conveying device, located outside the main chamber, is used to pick up and place the wafer at the wafer loading position.

17. The charged particle beam device as claimed in claim 8, characterized in that, Also includes: A driving device, which is connected to the ejector pin, is used to drive the ejector pin to rise and fall.

18. The charged particle beam device as claimed in claim 1, characterized in that, Also includes: A rotating device is disposed below the electrostatic chuck and connected to the electrostatic chuck to drive the electrostatic chuck to rotate.

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