Photomask cleaning device and semiconductor equipment

Abstract

The utility model provides a photomask cleaning device and semiconductor equipment, and the device comprises a clamping mechanism which is disposed corresponding to a photomask placement position and is used for clamping a photomask; the ultrasonic probe is arranged above the photomask and is used for emitting ultrasonic waves to the photomask, so that the photomask generates vibration; and the plurality of nozzles are arranged below the photomask at intervals and are used for spraying gas to the lower surface of the photomask so as to purge particulate matters on the photomask. According to the utility model, the ultrasonic probe emits the ultrasonic waves to the photomask, so that the photomask vibrates, and the particles on the photomask vibrate along with the photomask, thereby reducing the acting force between the particles and the surface of the photomask, and enabling the particles to be separated from the surface of the photomask more easily under the action of gas purging. Due to the fact that the nozzle is arranged below the photomask, blowing from bottom to top is achieved, and when the particulate matter is blown away from the photomask, the particulate matter can fall down under the action of the gravity of the particulate matter, and the particulate matter is prevented from being attached to the photomask again.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, and in particular to a photomask cleaning device and semiconductor equipment. Background Technology

[0002] Modern semiconductor manufacturing is essentially a process of continuous template pattern transfer. As the most basic template for different layers, the photomask is highly susceptible to contamination, which can significantly impact the product. The cleanliness of the photomask is a key factor in ensuring production quality. A photomask typically has two sides: a glass side and a film side. The film side protects the photomask from scratches, but it often attracts contaminants (pollutants), chemicals, etc., due to static electricity. As for the glass side, since the photomask is used with the glass side facing upwards, foreign particles tend to settle on it. Therefore, regular cleaning of the photomask is necessary to ensure that particles on the protective film do not affect the image formation and consequently impact the yield of the semiconductor manufacturing process.

[0003] Currently, photomask cleaning mainly relies on purging. When the Integrated Reticle Inspection System (IRIS) detects particulate matter on the photomask surface, the photomask must be removed from the exposure machine and cleaned from outside the machine. Current cleaning methods primarily rely on nitrogen purging. Typically, during operation, the nitrogen nozzle is moved near the particles, and nitrogen is released from top to bottom. This method can remove particles from the glass and film surfaces. However, for particles with strong adhesion or those on the film surface, nitrogen removal efficiency is very limited. Particles purged by nitrogen may also re-adhere to another location on the photomask. Furthermore, when the nitrogen gas cleanliness is insufficient, the top-down purging action may actually introduce some contamination.

[0004] In view of this, it is necessary to propose a photomask cleaning device and semiconductor equipment to solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a photomask cleaning device and semiconductor equipment to improve the pollution problem caused by the existing photomask cleaning method during the blowing process.

[0006] This utility model provides a photomask cleaning device, comprising:

[0007] A clamping mechanism is provided corresponding to the placement position of the photomask and is used to clamp the photomask;

[0008] An ultrasonic probe is positioned above the photomask and is used to emit ultrasonic waves into the photomask, causing the photomask to vibrate.

[0009] Several nozzles are spaced apart below the photomask and are used to spray gas toward the lower surface of the photomask to sweep away particulate matter on the photomask.

[0010] The beneficial effects of the photomask cleaning device provided by this utility model are as follows: Ultrasonic waves are emitted to the photomask via an ultrasonic probe, causing the photomask to vibrate. The particles on the photomask vibrate accordingly, thereby reducing the force between the particles and the photomask surface, making it easier for the particles to detach from the photomask surface under the action of gas blowing. Since the nozzle is located below the photomask, bottom-up blowing is achieved. When particles are blown off the photomask, they fall downwards due to their own gravity, preventing them from re-adhering to the photomask.

[0011] In one possible embodiment, the photomask cleaning device further includes a dust suction mechanism located below the photomask for sucking up particles on the photomask.

[0012] Its beneficial effects are as follows: the suction force of the dust collection mechanism will suck away the particles that have detached from the surface of the photomask, avoiding the residue of particles and improving the cleaning effect and efficiency of the photomask.

[0013] In one possible embodiment, the clamping mechanism includes at least one pair of first clamping components and a plurality of second clamping components that are offset from and spaced apart from the first clamping components, wherein the first clamping components and the second clamping components are independently adjustable.

[0014] Its beneficial effects are as follows: by clamping the photomask at different positions by the first clamping component and the second clamping component respectively, and by changing the clamping position, the clamping position can be cleaned, thereby avoiding cleaning dead corners caused by the clamping position blocking.

[0015] In one possible embodiment, the photomask cleaning device further includes a first clamping drive connected to the first clamping assembly and used to control the first clamping assembly to switch between opening and clamping; and / or,

[0016] The photomask cleaning device also includes a second clamping drive connected to the second clamping assembly and used to control the second clamping assembly to switch between opening and clamping.

[0017] Its beneficial effects are as follows: the first clamping drive unit can independently control the first clamping assembly to clamp or release the photomask. Similarly, the second clamping drive unit can independently control the second clamping assembly to clamp or release the photomask.

[0018] In one possible embodiment, the photomask cleaning device further includes a first rotation drive connected to the first clamping assembly and used to control the rotational adjustment of the first clamping assembly; and / or,

[0019] The photomask cleaning device also includes a second rotation drive connected to the second clamping assembly and used to control the rotational adjustment of the second clamping assembly.

[0020] Its beneficial effects are as follows: the rotation of the first clamping component can be controlled independently by the first rotation drive component, and the rotation of the second clamping component can be controlled independently by the second rotation drive component, thereby realizing the control of the front and back flipping and tilt angle of the photomask.

[0021] In one possible embodiment, the photomask cleaning device further includes a vibration monitoring element disposed on the clamping mechanism for monitoring the vibration of the photomask, and a controller connected to the vibration monitoring element. The controller is used to compare the real-time monitored photomask vibration frequency with a preset vibration frequency. When the photomask vibration frequency is greater than or equal to the preset vibration frequency, the ultrasonic frequency of the ultrasonic probe is reduced.

[0022] Its beneficial effect is that when the vibration frequency of the photomask is greater than or equal to the preset vibration frequency, the controller controls the ultrasonic probe to reduce the ultrasonic frequency, thereby preventing the photomask from being damaged due to excessive vibration frequency.

[0023] In one possible embodiment, the photomask cleaning device further includes a guide rail assembly, on which a plurality of the nozzles are mounted, the nozzles being movable and adjustable along the extension direction of the guide rail assembly and rotatable and adjustable around the guide rail assembly.

[0024] Its beneficial effects are: the position and tilt angle of the nozzle can be flexibly adjusted according to the position of the particles or the preset blowing area on the photomask, thereby adjusting the blowing position, blowing angle and blowing force, thus improving the cleaning flexibility and cleaning effect.

[0025] In one possible embodiment, the photomask cleaning device further includes a plurality of mounting seats movably and adjustablely disposed on the guide rail assembly and a spherical adjusting member disposed on the nozzle. The mounting seats and the adjusting members are arranged in a one-to-one correspondence. The mounting seats are provided with grooves adapted to the adjusting members. The adjusting members are rotatably disposed in the grooves. The mounting seats are threadedly connected with fasteners that are offset from the groove openings. The fasteners extend into the grooves and abut against the adjusting members to lock the adjusting members in place within the grooves. After the fasteners are released from locking the adjusting members, the adjusting members can be rotated and adjusted.

[0026] Its beneficial effect is that after the fastener is released from locking the adjusting member, the adjusting member can be rotated and adjusted, thereby adjusting the tilt angle of the nozzle. By adjusting the fastener, the adjusting member can be locked and fixed, and the nozzle can be locked to the required tilt angle.

[0027] In one possible embodiment, the photomask cleaning device further includes a support for supporting the photomask before the clamping mechanism clamps the photomask.

[0028] Its beneficial effect is that: before the clamping mechanism clamps the photomask, the photomask is supported by the support member, and after the clamping mechanism clamps the photomask, the support member is removed.

[0029] This invention also provides a semiconductor device, including: a photomask cleaning device as described in any of the above embodiments. Attached Figure Description

[0030] Figure 1 This is a front view of the photomask cleaning device of this utility model in one embodiment.

[0031] Figure 2 This is a top view of one embodiment of the photomask cleaning device of this utility model.

[0032] Figure 3 This is a schematic diagram of the first clamping component clamping the photomask in the photomask cleaning device of this utility model.

[0033] Figure 4 This is a schematic diagram of the second clamping component clamping the photomask in the photomask cleaning device of this utility model.

[0034] Figure 5 This is a schematic diagram of the first clamping component, the first clamping drive component, the first rotation drive component, and the vibration monitoring component in the photomask cleaning device of this utility model.

[0035] Figure 6 This is a schematic diagram of the photomask cleaning device of this utility model, including the guide rail, mounting base, nozzle, and adjusting components.

[0036] Explanation of reference numerals in the attached drawings: 111, First clamping assembly; 1111, First clamping plate; 112, Second clamping assembly; 1121, Second clamping plate; 120, Ultrasonic probe; 130, Nozzle; 131, Adjusting component; 140, Dust suction mechanism; 150, First clamping drive component; 160, First rotation drive component; 170, Vibration monitoring component; 180, Guide rail assembly; 181, Sub-guide rail; 190, Mounting base; 191, Groove; 192, Fastener; 200, Photomask. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0038] To address the problems existing in the prior art, embodiments of this utility model provide a photomask cleaning device, see [link to relevant documentation]. Figure 1 and Figure 2 The photomask cleaning device includes a clamping mechanism, an ultrasonic probe 120, and several nozzles 130. The clamping mechanism is positioned corresponding to the photomask 200 and is used to clamp the photomask 200. The ultrasonic probe 120 is positioned above the photomask 200 and is used to emit ultrasonic waves into the photomask 200, causing the photomask 200 to vibrate. The several nozzles 130 are spaced apart below the photomask 200 and are used to spray gas onto the lower surface of the photomask 200 to blow away particulate matter on the photomask 200. The gas is an inert gas such as nitrogen or hydrogen.

[0039] In this embodiment, ultrasonic waves are transmitted through the air to the photomask 200 and interact with the particles on the photomask 200, thereby reducing the force between the particles and the surface of the photomask 200. This makes it easier for the particles to detach from the surface of the photomask 200 under the impact of the gas. The ultrasonic frequency is not less than 20 kHz, and 35 kHz is optimally recommended. Since the nozzle 130 is located below the photomask 200, the gas blows the photomask 200 from bottom to top. When the particles are blown off the photomask 200, they fall downwards due to their own gravity. This solution uses a combination of suction and bottom-up blowing, which greatly improves the pollution problem caused by the blowing process. At the same time, the combination of ultrasonic vibration, blowing, and gravity cleaning methods greatly improves the particle removal efficiency and enhances the cleaning effect.

[0040] In one embodiment, see Figure 1 The photomask cleaning device also includes a vacuuming mechanism 140 located below the photomask 200 for sucking up particles from the photomask 200. When particles are blown off the photomask 200, they are collected and stored in the vacuuming mechanism 140 by their own gravity, the lateral blowing force of the gas from the nozzle 130, and the suction force of the vacuuming mechanism 140 below. The suction force of the vacuuming mechanism 140 can be controlled by its internal flow control device. The vacuuming mechanism 140 also has an automatic cleaning function, which can periodically clean the collected particles and pipelines. The particle storage box can also be directly replaced.

[0041] In one embodiment, see Figure 1and Figure 2 The clamping mechanism includes at least one pair of first clamping components 111 and a plurality of second clamping components 112 that are offset from and spaced apart from the first clamping components 111. The first clamping components 111 and the second clamping components 112 are independently adjustable.

[0042] The photomask 200 is clamped at different positions by the first clamping component 111 and the second clamping component 112 respectively. Since the first clamping component 111 and the second clamping component 112 can be adjusted independently, when the first clamping component 111 is clamping, the second clamping component 112 is not clamping, so the clamping position of the second clamping component 112 can be cleaned. When the second clamping component 112 is clamping, the first clamping component 111 is not clamping, so the clamping position of the first clamping component 111 can be cleaned. This can avoid cleaning dead corners caused by the clamping position.

[0043] Further, see Figure 4 The area where the first clamping component 111 clamps the photomask 200 is strip-shaped, see [reference]. Figure 3 The area where the second clamping component 112 clamps the photomask 200 is block-shaped.

[0044] Furthermore, see Figure 1 The first clamping assembly 111 includes a pair of first clamping plates 1111, see [link to previous section] Figure 2 The second clamping assembly 112 includes a pair of second clamping plates 1121.

[0045] In one specific embodiment, the photomask 200 is square in shape, see [reference]. Figure 1 Each pair of first clamping components 111 is symmetrically located on opposite sides of the photomask 200, see [reference]. Figure 2 The second clamping components 112 are four in number and are located at the four corners of the photomask 200.

[0046] In one embodiment, see Figure 5 The photomask cleaning device also includes a first clamping drive 150 connected to the first clamping assembly 111 and used to control the first clamping assembly 111 to switch between opening and clamping.

[0047] Furthermore, the first clamping drive 150 is connected to a pair of first clamping plates 1111 and is used to drive one of the first clamping plates 1111 to move closer to or further away from the other first clamping plate 1111. The first clamping drive 150 can be a linear module, a motor, an electric telescopic rod, a cylinder, etc. Figure 5 The first clamping drive unit 150 shown is a linear module. The first clamping drive unit 150 can be used to individually control the pair of first clamping plates 1111 to clamp or release the photomask 200.

[0048] In one embodiment, the photomask cleaning device further includes a second clamping drive connected to the second clamping assembly 112 and used to control the second clamping assembly 112 to switch between opening and clamping.

[0049] Furthermore, the second clamping drive is connected to a pair of second clamping plates 1121 and is used to drive one of the second clamping plates 1121 to move closer to or further away from the other second clamping plate 1121. The second clamping drive can be a linear module, a motor, an electric telescopic rod, a cylinder, etc. The second clamping drive can independently control the pair of second clamping plates 1121 to clamp or release the photomask 200.

[0050] In one embodiment, see Figure 5 The photomask cleaning device also includes a first rotation drive 160 connected to the first clamping assembly 111 and used to control the rotation adjustment of the first clamping assembly 111.

[0051] In one embodiment, the photomask cleaning device further includes a second rotation drive connected to the second clamping assembly 112 and used to control the rotational adjustment of the second clamping assembly 112.

[0052] In some embodiments, see Figure 5 The first rotation drive 160 is disposed on the first clamping drive 150, and the second rotation drive is disposed on the second clamping drive. The first rotation drive 160 and the second rotation drive are rotary cylinders, motors, etc.

[0053] The first rotation drive 160 can independently control the rotation of the first clamping assembly 111, and the second rotation drive can independently control the rotation of the second clamping assembly 112. By controlling the synchronous rotation of several first clamping assemblies 111 or several second clamping assemblies 112, the front and back of the photomask 200 can be flipped to achieve cleaning of the front and flipped sides of the photomask 200 respectively. In addition, according to different cleaning process requirements, several first clamping assemblies 111 or several second clamping assemblies 112 can be adjusted to the corresponding tilt angle, thereby adjusting the photomask 200 to the required tilt angle to achieve cleaning at different tilt angles.

[0054] In one specific embodiment, see Figure 1 and Figure 2 The first clamping component 111 and the second clamping component 112 are used to clamp the edge of the photomask 200 to reduce the damage to the photomask 200 caused by clamping.

[0055] In one embodiment, see Figure 6The photomask cleaning device also includes a vibration monitoring element 170 mounted on the clamping mechanism for monitoring the vibration of the photomask 200, and a controller connected to the vibration monitoring element 170. The controller is used to compare the real-time monitored vibration frequency of the photomask 200 with a preset vibration frequency. When the vibration frequency of the photomask 200 is greater than or equal to the preset vibration frequency, the ultrasonic frequency of the ultrasonic probe 120 is reduced.

[0056] The vibration frequency of the photomask 200 is monitored in real time by the vibration monitoring device 170, and the vibration frequency of the photomask 200 monitored in real time is compared with the preset vibration frequency by the controller. When the vibration frequency of the photomask 200 is greater than or equal to the preset vibration frequency, the controller controls the ultrasonic probe 120 to reduce the ultrasonic frequency, thereby reducing the vibration frequency of the photomask 200 and thus preventing the photomask 200 from being damaged due to excessive vibration frequency.

[0057] In one embodiment, see Figure 2 The photomask cleaning device also includes a guide rail assembly 180, on which several nozzles 130 are mounted. The nozzles 130 can be moved and adjusted along the extension direction of the guide rail assembly 180 and can be rotated and adjusted around the guide rail assembly 180. Based on the position of the particles or a preset blowing area on the photomask 200, the position and tilt angle of the nozzles 130 can be flexibly adjusted to achieve more precise blowing and cleaning, thereby improving the flexibility and effectiveness of the cleaning process.

[0058] In one embodiment, see Figure 2 and Figure 6 The photomask cleaning device also includes several mounting seats 190 movably and adjustablely mounted on the guide rail assembly 180, and a spherical adjusting member 131 mounted on the nozzle 130. Each mounting seat 190 corresponds to one adjusting member 131. Each mounting seat 190 has a groove 191 adapted to the adjusting member 131, and the adjusting member 131 is rotatably mounted within the groove 191. A fastener 192, threadedly connected to the mounting seat 190 and offset from the groove 191, extends into the groove 191 and abuts against the adjusting member 131, locking the adjusting member 131 securely within the groove 191. After releasing the fastener 192 from locking the adjusting member 131, the adjusting member 131 can be rotated for adjustment. The fastener 192 can be a bolt, screw, etc.

[0059] When it is necessary to adjust the tilt angle of the nozzle 130, the fastener 192 is moved out of the groove 191 by tightening the fastener 192 to release the fastener 192 from locking the adjusting member 131. At this time, the adjusting member 131 can rotate in the groove 191, so that the nozzle 130 can be rotated and adjusted to the required tilt angle. Then, the fastener 192 is moved into the groove 191 by tightening the fastener 192 so that the end of the fastener 192 is pressed against the adjusting member 131, so that the adjusting member 131 is locked and fixed in the groove 191.

[0060] In one specific embodiment, see Figure 2 and Figure 6 The guide rail assembly 180 is provided with several displacement driving components (not shown in the figure). The displacement driving components are arranged one-to-one with the mounting base 190 and are drivenly connected to the corresponding mounting base 190. The displacement driving components are used to drive the mounting base 190 to move along the guide rail assembly 180. The displacement driving components are linear modules, electric telescopic rods, cylinders, etc.

[0061] In one specific embodiment, see Figure 2 and Figure 6 The photomask 200 is rectangular in shape. The guide rail assembly 180 includes four sub-guide rails 181 corresponding to the four sides of the photomask 200. Each sub-guide rail 181 has a groove extending along its direction. The mounting base 190 of the nozzle 130 slides in the groove. By adjusting the position of the mounting base 190 on the sub-guide rails 181, the position of the nozzle 130 can be adjusted. The nozzle 130 is angled to provide lateral gas purging force to the photomask 200, effectively removing particles from the photomask 200 from all directions. The angle of the nozzle 130 can be adjusted between 80° and 10°. A flow control element is also provided on the nozzle 130 to regulate the gas flow rate of each nozzle 130. The long side of the photomask 200 corresponds to 6 nozzles 130, and the short side of the photomask 200 corresponds to 4 nozzles 130. The spacing between two adjacent nozzles 130 on the same side is 1.5-2.5cm, and each nozzle 130 is independently controlled.

[0062] In one specific embodiment, the photomask cleaning device further includes a support member (not shown) for supporting the photomask 200 before the clamping mechanism clamps it. The photomask 200 is supported by the support member before the clamping mechanism clamps it, and the support member is removed after the clamping mechanism clamps the photomask 200.

[0063] In one specific embodiment, the ultrasonic probe 120 is positioned at the center of the photomask 200.

[0064] This invention also provides a semiconductor device, including: a photomask cleaning device as described in any of the above embodiments.

[0065] In the description of this utility model, it should be understood that the terms "comprising" and "having" as used herein, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0066] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0067] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0068] While the embodiments of this utility model have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of this utility model as set forth in the claims. Furthermore, the utility model described herein may have other embodiments and can be implemented or realized in various ways. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains.

Claims

1. A photomask cleaning device, characterized in that, include: A clamping mechanism is provided corresponding to the placement position of the photomask and is used to clamp the photomask; An ultrasonic probe is positioned above the photomask and is used to emit ultrasonic waves into the photomask, causing the photomask to vibrate. Several nozzles are spaced apart below the photomask and are used to spray gas toward the lower surface of the photomask to sweep away particulate matter on the photomask. Each nozzle is independently adjustable.

2. The photomask cleaning device according to claim 1, characterized in that, It also includes a dust suction mechanism located below the photomask for sucking up particles on the photomask.

3. The photomask cleaning device according to claim 1, characterized in that, The clamping mechanism includes at least one pair of first clamping components and a plurality of second clamping components that are offset from and spaced apart from the first clamping components. The first clamping components and the second clamping components are independently adjustable.

4. The photomask cleaning device according to claim 3, characterized in that, It also includes a first clamping drive connected to the first clamping assembly and used to control the switching of the first clamping assembly between opening and clamping; and / or, It also includes a second clamping drive connected to the second clamping assembly and used to control the second clamping assembly to switch between opening and clamping.

5. The photomask cleaning device according to claim 3, characterized in that, It also includes a first rotation drive connected to the first clamping assembly and used to control the rotational adjustment of the first clamping assembly; and / or, It also includes a second rotation drive connected to the second clamping assembly and used to control the rotational adjustment of the second clamping assembly.

6. The photomask cleaning device according to claim 1, characterized in that, It also includes a vibration monitoring device disposed on the clamping mechanism for monitoring the vibration of the photomask, and a controller connected to the vibration monitoring device. The controller is used to compare the real-time monitored photomask vibration frequency with a preset vibration frequency. When the photomask vibration frequency is greater than or equal to the preset vibration frequency, the ultrasonic frequency of the ultrasonic probe is reduced.

7. The photomask cleaning device according to claim 1, characterized in that, It also includes a guide rail assembly, on which a plurality of the nozzles are mounted, the nozzles being movable and adjustable along the extension direction of the guide rail assembly and being rotatable.

8. The photomask cleaning device according to claim 7, characterized in that, It also includes several mounting seats that are movably and adjustablely disposed on the guide rail assembly and a spherical adjusting member disposed on the nozzle. The mounting seats and the adjusting members are arranged in a one-to-one correspondence. The mounting seats are provided with grooves that are adapted to the adjusting members. The adjusting members are rotatably disposed in the grooves. The mounting seats are threadedly connected with fasteners that are offset from the groove openings. The fasteners extend into the grooves and press against the adjusting members to lock the adjusting members in place within the grooves. After the fasteners are released from locking the adjusting members, the adjusting members can be rotated and adjusted.

9. The photomask cleaning device according to any one of claims 1-8, characterized in that, It also includes a support member for supporting the photomask before the clamping mechanism clamps the photomask.

10. A semiconductor device, characterized in that, include: The photomask cleaning device as described in any one of claims 1-9.

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