Double-station wafer exposure machine table

Abstract

The utility model provides a double-station wafer exposure machine table which comprises a process cavity used for carrying out exposure treatment on a wafer; the first bearing table and the second bearing table are movably arranged in the process cavity, the first bearing table is provided with a first bearing surface, the second bearing table is provided with a second bearing surface, and the first bearing surface and the second bearing surface are both used for bearing wafers; the measuring assembly is arranged in the process cavity; and when the exposed wafer on the first bearing surface or the second bearing surface is conveyed out and the gap of the next wafer to be measured is received, the measuring assembly is used for measuring the surface flatness of the first bearing surface or the second bearing surface which does not bear the wafer. The double-station wafer exposure machine provided by the utility model can measure the surface flatness of the first bearing surface and the second bearing surface in time, so that the measurement accuracy and timeliness are improved, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing equipment, in particular to a double-station wafer exposure machine. Background Art

[0002] Exposure equipment is a critical piece of equipment in semiconductor chip manufacturing. The primary function of the exposure equipment's worktable is to support wafers at high speeds and high accelerations, achieving nanometer-level positioning. This allows for the loading and unloading, pre-alignment, and alignment processes of the lithography process, while also coordinating with the mask stage to complete the exposure. Currently, mainstream exposure machines utilize dual-stage exposure. For example, while one stage performs the necessary pre-exposure measurements, the other performs normal exposure. When both stages are complete, they swap positions. The stage that has completed measurements performs normal exposure, while the previously exposed stage moves to a predetermined position. A robotic arm removes the wafer and receives a new wafer from another arm for measurement. This entire process repeats itself throughout the machine's operation.

[0003] Before exposure, the exposure machine measures the surface height of the wafer to be exposed at the measurement end. If the same height is detected on consecutive wafers and exceeds the programmed height on the machine, the machine triggers a self-cleaning mechanism to ensure that the workpiece stage does not suffer from backside contamination and impact subsequent products. The mainstream exposure machine self-cleaning process involves the following: if the same height is detected on three or four consecutive wafers and exceeds the programmed height, a control command is issued to stop the film feed at the coating and developer interface. After all wafers currently in the machine have been measured and exposed normally, a special grinding stone is used to perform a targeted cleaning of the wafer stage surface.

[0004] This measurement and cleaning method cannot directly and promptly assess the contamination status of the workpiece stage. Its judgment is delayed, leading to further contamination of wafers still in the tool prior to cleaning. Furthermore, the impact can extend beyond the intended observation range of 3-4 wafers, increasing production costs. Furthermore, because the wafer surface is coated with photoresist, surface polymer films, and underlying deposited films, optical signal loss occurs during wafer measurement, reducing the signal-to-noise ratio of the output actual height signal and thus affecting the accuracy and stability of the final measurement results. Utility Model Content

[0005] The purpose of the utility model is to provide a dual-station wafer exposure machine, which can timely measure the surface flatness of a first carrying surface and a second carrying surface, thereby improving the accuracy and timeliness of the measurement and reducing the production cost.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a dual-station wafer exposure machine, comprising:

[0007] A process chamber, used for exposing the wafer;

[0008] a first carrying platform and a second carrying platform movably disposed in the process chamber, wherein the first carrying platform has a first carrying surface, and the second carrying platform has a second carrying surface, and both the first carrying surface and the second carrying surface are used for carrying wafers;

[0009] A measuring component is disposed in the process chamber;

[0010] When the exposed wafer on the first carrying surface or the second carrying surface is transferred out and the next wafer to be measured is received, the measuring component is used to measure the surface flatness of the first carrying surface or the second carrying surface without a wafer.

[0011] The beneficial effect of the present invention is that by placing the measurement component within the process chamber, the surface of the first or second loading surface can be directly measured when no wafer is loaded on the first or second loading surface, thereby ensuring the timeliness and accuracy of the flatness measurement of the first or second loading surface. When the height of the protrusion on the first or second loading surface is measured to be greater than a preset height threshold, the operator can be promptly reminded that the first or second loading surface needs to be processed, thereby improving the reliability of the wafer exposure process and reducing production costs.

[0012] In some embodiments, the process chamber includes an exposure chamber and a measurement chamber that are interconnected, the measurement component is disposed in the measurement chamber, and the exposure chamber is used to perform exposure processing on the wafer;

[0013] When the exposed wafer is transferred out of the exposure chamber and the gap for the next wafer to be measured is received, the measurement component is used to measure the surface flatness of the first or second loading surface located in the measurement chamber. Its beneficial effect is that: the process chamber includes an exposure chamber and a measurement chamber that are interconnected, the exposure chamber is used to perform exposure processing on the wafer, and the measurement component is arranged in the measurement chamber to measure the flatness of the wafer. In the exposure chamber, the exposed wafer is transferred out by the robotic arm and the gap for the next wafer to be measured is received. At this time, the measurement component can measure the surface flatness of the first or second loading surface located in the measurement chamber, thereby improving the efficiency of measurement and ensuring the timeliness of measurement.

[0014] In some embodiments, the dual-station wafer exposure machine further includes a driving mechanism disposed in the process chamber;

[0015] The first carrying platform and the second carrying platform are provided on the driving mechanism, and the driving mechanism is used to drive the first carrying platform and the second carrying platform to move along the first direction and the second direction;

[0016] The first direction and the second direction are perpendicular to each other, and the moving plane formed by the first direction and the second direction is parallel to both the first carrying surface and the second carrying surface. The advantageous effect is that, by providing a driving mechanism in the process chamber, the first carrying stage and the second carrying stage can be transferred between the exposure chamber and the measurement chamber.

[0017] In some embodiments, the measurement assembly includes a first laser measuring device and a first image receiver, the first laser measuring device and the first image receiver being arranged relative to each other along the first direction. The first laser measuring device is configured to emit measurement light toward the first supporting surface or the second supporting surface, and the first image receiver is configured to receive measurement light reflected from the first supporting surface or the second supporting surface. This advantageous effect is that the first laser measuring device and the first image receiver are arranged relative to each other along the first direction. When the driving mechanism drives the first supporting platform or the second supporting platform to move along the first direction within the measurement chamber, the first laser measuring device and the first image receiver can measure the first supporting surface or the second supporting surface along the first direction, thereby achieving flatness measurement of the first supporting surface or the second supporting surface along the first direction, thereby obtaining a scanning cloud map along the first direction.

[0018] In some embodiments, the measurement assembly further includes a second laser measuring device and a second image receiver, the second laser measuring device and the second image receiver being positioned relative to each other along the second direction. The second laser measuring device is configured to emit measurement light toward the first or second supporting surface, and the second image receiver is configured to receive measurement light reflected from the first or second supporting surface. This advantageously provides the following advantages: The second laser measuring device and the second image receiver are positioned relative to each other along the second direction. When the drive mechanism drives the first or second supporting platform to move along the second direction within the measurement chamber, the second laser measuring device and the second image receiver can measure the first or second supporting surface along the second direction, thereby measuring the flatness of the first or second supporting surface along the second direction, thereby generating a scanning nephogram along the second direction. Subsequently, the scanning nephogram along the first and second directions can be linearly superimposed and edge-corrected to form a three-dimensional model, generating a final nephogram of the height and topography of the platform surface.

[0019] In some embodiments, the dual-station wafer exposure tool further includes a controller, wherein the controller is electrically connected to the first laser measurer, the first image receiver, the second laser measurer, the second image receiver, and the driving mechanism;

[0020] When the controller controls the driving mechanism to drive the first carrying surface or the second carrying surface in the measuring chamber to move along a first direction, the controller controls the first laser measuring device and the first image receiver to operate, and controls the second laser measuring device and the second image receiver to shut down;

[0021] When the controller controls the driving mechanism to drive the first carrying surface or the second carrying surface located in the measuring chamber to move along the second direction, the controller controls the first laser measurer and the first image receiver to turn off, and controls the second laser measurer and the second image receiver to work.

[0022] In some embodiments, the dual-station wafer exposure machine further includes a grinding mechanism disposed in the process chamber;

[0023] The grinding mechanism is electrically connected to the controller, and the grinding mechanism has a grinding head;

[0024] When the measuring assembly detects that the height of the protrusion on the first or second bearing surface is greater than a preset height threshold, the controller controls the grinding head to grind the first or second bearing surface. This advantageous effect is that the grinding mechanism is electrically connected to the controller, and when the measuring assembly detects that the height of the protrusion on the first or second bearing surface is greater than the preset height threshold, the controller can promptly control the grinding head to grind the first or second bearing surface, thereby improving the timeliness of the treatment of the first or second bearing surface.

[0025] In some embodiments, the dual-station wafer exposure machine further includes a robot disposed within the process chamber, the robot being configured to transfer exposed wafers out of the process chamber. This advantageously allows the robot to transfer exposed wafers out of the exposure chamber, providing a gap for the next wafer to be measured. During this time, the measurement assembly can measure the surface flatness of the first or second supporting surfaces, which are not supporting wafers, thereby ensuring efficient measurement.

[0026] In some embodiments, the first laser measurer and the second laser measurer are both 3D line laser sensors. The beneficial effect is that by using 3D line laser sensors for scanning measurement, the speed and accuracy of measurement are improved.

[0027] In some embodiments, the measurement component further comprises an alarm;

[0028] The alarm is electrically connected to the controller;

[0029] When the measurement component detects that the height of the protrusion on the first or second supporting surface exceeds a preset height threshold, the controller sends an alarm signal to the alarm, which then sounds an alarm. This advantageously allows the controller to transmit the protrusion location and height information to the machine's data storage system for storage, and to display an alarm message on the machine interface. Upon receiving the alarm message, the alarm's red indicator lights up, alerting engineers to review and address the situation. This alarm can provide timely reminders for engineers to review and assess measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the internal structure of a dual-station wafer exposure machine according to an embodiment of the present invention;

[0031] Figure 2 This is a top view of the dual-station wafer exposure machine according to an embodiment of the present invention;

[0032] Figure 3 This is a front view of a dual-station wafer exposure machine according to an embodiment of the present invention.

[0033] Reference numerals:

[0034] Process chamber 1, exposure chamber 11, measurement chamber 12, first carrier platform 2, first carrier surface 21, second carrier platform 3, second carrier surface 31, measurement component 4, first laser measurer 41, first image receiver 42, second laser measurer 43, second image receiver 44, controller 45, alarm 46, drive mechanism 5, manipulator 6. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The words "including" and similar words used in this article mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Unless otherwise specified, the "connection" described in this article can be a direct connection or an indirect connection, that is, a connection through an intermediate.

[0036] In view of the problems existing in the prior art, the embodiment of the present invention provides a dual-station wafer exposure machine, referring to Figure 1As shown, the dual-station wafer exposure machine includes a process chamber 1, a first carrier 2, a second carrier 3, and a measurement assembly 4. The first carrier 2 and the second carrier 3 are movably disposed within the process chamber 1. The first carrier 2 has a first carrier surface 21, and the second carrier 3 has a second carrier surface 31. The first carrier surface 21 and the second carrier surface 31 are at the same height and parallel to each other. Both the first carrier surface 21 and the second carrier surface 31 are used to carry wafers for exposure processing within the process chamber 1. The measurement assembly 4 is disposed within the process chamber 1 and is used to measure the flatness of the first carrier surface 21 and the second carrier surface 31.

[0037] When the exposed wafer on the first carrying surface 21 or the second carrying surface 31 is transferred out of the process chamber 1 and an idle gap is left to receive the next wafer to be measured, the measuring component 4 is used to measure the surface flatness of the first carrying surface 21 or the second carrying surface 31 without a wafer.

[0038] Specifically, in this embodiment, since a dual-station wafer exposure machine is used, when the wafer on the first carrier 2 is undergoing exposure processing, the wafer that has been exposed and processed on the second carrier 3 can be transferred out of the process chamber 1. When the exposed wafer is transferred out by the robotic arm and receives the next wafer to be measured, the measuring component 4 can be used to directly measure the second carrier surface 31 to obtain the flatness of its surface. When the height of the protrusion at a certain position on the second carrier surface 31 is greater than the preset height, the exposure processing is suspended, and after all wafers are transferred out of the process chamber, the second carrier surface 31 is cleaned.

[0039] Similarly, when the wafer on the second carrier 3 is undergoing exposure processing, the wafer that has been exposed and processed on the first carrier 2 can be transferred out of the process chamber 1. When the exposed wafer is transferred out by the robotic arm and receives the next wafer to be measured, the measuring component 4 can be used to directly measure the first carrier surface 21 to obtain the flatness of its surface. When the height of the protrusion at a certain position on the first carrier surface 21 is greater than the preset height, the exposure processing is suspended, and the first carrier surface 21 is cleaned after all wafers are transferred out of the process chamber.

[0040] It will be appreciated that in this embodiment, by directly measuring the first supporting surface 21 or the second supporting surface 31 using the measurement assembly 4, measurement accuracy is ensured. Furthermore, by measuring the first supporting surface 21 or the second supporting surface 31 between the time when an exposed wafer is transferred out and the time when a newly transferred wafer to be measured is measured, measurement timeliness is improved, thereby reducing the number of affected wafers and thereby lowering production costs.

[0041] refer to Figure 1 and Figure 2 As shown, in some embodiments, the process chamber 1 includes an exposure chamber 11 and a measurement chamber 12 that are interconnected. The measurement assembly 4 is disposed in the measurement chamber 12. The exposure chamber 11 is used to perform exposure processing on the wafer. A drive mechanism 5 is disposed in the process chamber 1. The first carrier 2 and the second carrier 3 are disposed on the drive mechanism 5. The drive mechanism 5 is used to drive the first carrier 2 and the second carrier 3 to move along a first direction and a second direction. The first direction and the second direction are perpendicular to each other, and the movement plane formed by the first direction and the second direction is parallel to both the first carrier surface 21 and the second carrier surface 31.

[0042] It should be noted that, in this embodiment, the first direction and the second direction are used to limit the directions in which the driving mechanism 5 can move. During the actual movement process, the driving mechanism 5 can drive the first carrier 2 and the second carrier 3 to move back and forth along the first direction and the second direction. For example, when the wafer on the first carrier 2 is moved to the measurement chamber 12 by the driving mechanism 5 after exposure processing, the second carrier 3 transfers the measured wafer to the exposure chamber 11 through the driving mechanism 5. Subsequently, the robot 6 located in the process chamber 1 transfers the exposed wafer on the first carrier 2. Before another robot transfers the wafer to be measured to the first carrier 2, the measurement component 4 is used to measure the surface flatness of the first carrier surface 21.

[0043] In some embodiments, the measuring component 4 includes a first laser measurer 41 and a first image receiver 42. The first laser measurer 41 and the first image receiver 42 are arranged opposite to each other along the first direction. The first laser measurer 41 is used to emit measuring light to the first bearing surface 21 or the second bearing surface 31, and the first image receiver 42 is used to receive measuring light reflected from the first bearing surface 21 or the second bearing surface 31.

[0044] In this embodiment, when the first laser measuring device 41 and the first image receiver 42 are used to measure the first carrying surface 21 or the second carrying surface 31, the driving mechanism 5 drives the first carrying platform 2 or the second carrying platform 3 to move along the first direction in the measuring chamber 12 to measure the first carrying surface 21 or the second carrying surface 31 in the first direction, so as to realize the flatness measurement of the first carrying surface 21 or the second carrying surface 31 along the first direction, thereby obtaining a scanning cloud map along the first direction.

[0045] Furthermore, the measuring component 4 also includes a second laser measurer 43 and a second image receiver 44, and the second laser measurer 43 and the second image receiver 44 are arranged opposite to each other along the second direction. The second laser measurer 43 is used to emit measuring light to the first bearing surface 21 or the second bearing surface 31, and the second image receiver 44 is used to receive measuring light reflected from the first bearing surface 21 or the second bearing surface 31.

[0046] In this embodiment, when the second laser measuring device 43 and the second image receiver 44 are used to measure the first carrying surface 21 or the second carrying surface 31, the driving mechanism 5 drives the first carrying platform 2 or the second carrying platform 3 to move in the second direction within the measurement chamber 12 to measure the first carrying surface 21 or the second carrying surface 31 in the second direction, thereby achieving a flatness measurement of the first carrying surface 21 or the second carrying surface 31 along the second direction, thereby obtaining a scanning nephogram along the second direction. Subsequently, the scanning nephogram along the first direction and the scanning nephogram along the second direction can be linearly superimposed and edge-corrected to form a final nephogram of the height topography of the stage surface.

[0047] In some embodiments, the first laser measurer 41 and the second laser measurer 43 are both 3D line laser sensors. The first image receiver 42 and the second image receiver 44 are both cameras.

[0048] refer to Figures 1 to 3 As shown, in some embodiments, the measuring component 4 further includes a controller 45 , and the controller 45 is electrically connected to the first laser measurer 41 , the first image receiver 42 , the second laser measurer 43 , the second image receiver 44 and the driving mechanism 5 .

[0049] In this embodiment, when the controller 45 controls the driving mechanism 5 to move the first carrying surface 21 or the second carrying surface 31 within the measurement chamber 12 in a first direction, the controller 45 controls the first laser measuring device 41 and the first image receiver 42 to operate, and controls the second laser measuring device 43 and the second image receiver 44 to shut down. When the controller 45 controls the driving mechanism 5 to move the first carrying surface 21 or the second carrying surface 31 within the measurement chamber 12 in a second direction, the controller 45 controls the first laser measuring device 41 and the first image receiver 42 to shut down, and controls the second laser measuring device 43 and the second image receiver 44 to operate.

[0050] In some embodiments, the measurement assembly 4 further includes a grinding mechanism disposed within the process chamber 1, the grinding mechanism being electrically connected to the controller 45 and having a grinding head. When the measurement assembly 4 detects that the protrusion height of the first carrying surface 21 or the second carrying surface 31 is greater than a preset height threshold, the controller 45 controls the grinding head to grind the first carrying surface 21 or the second carrying surface 31 to keep the first carrying surface 21 or the second carrying surface 31 clean, thereby ensuring that the flatness of the first carrying surface 21 or the second carrying surface 31 meets specified requirements.

[0051] In some embodiments, the measuring component 4 further includes an alarm 46, which is electrically connected to the controller 45. When the measuring component 4 detects that the height of the protrusion on the first supporting surface 21 or the second supporting surface 31 is greater than a preset height threshold, the controller 45 transmits the protrusion position and height information to the machine data storage system for storage and pops up an alarm message on the machine interface. Upon receiving the alarm message, the red indicator light of the alarm 46 lights up to remind engineers to check and handle the situation.

[0052] In this embodiment, the alarm 46 is provided outside the process chamber. By providing the alarm 46 , engineers can be reminded to check and judge the measurement results in a timely manner.

[0053] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A dual-station wafer exposure machine, characterized in that: include: A process chamber, used for exposing the wafer; a first carrying platform and a second carrying platform movably disposed in the process chamber, wherein the first carrying platform has a first carrying surface, and the second carrying platform has a second carrying surface, and both the first carrying surface and the second carrying surface are used for carrying wafers; A measuring component is disposed in the process chamber; When the exposed wafer on the first carrying surface or the second carrying surface is transferred out and the next wafer to be measured is received, the measuring component is used to measure the surface flatness of the first carrying surface or the second carrying surface without a wafer.

2. The dual-station wafer exposure machine according to claim 1, characterized in that: The process chamber comprises an exposure chamber and a measurement chamber that are interconnected, the measurement component is arranged in the measurement chamber, and the exposure chamber is used to perform exposure processing on the wafer; When the exposed wafer is transferred out of the exposure chamber and a gap is formed between the exposure chamber and the next wafer to be measured, the measuring component is used to measure the surface flatness of the first carrying surface or the second carrying surface in the measurement chamber.

3. The dual-station wafer exposure machine according to claim 2, characterized in that: Also included is a driving mechanism disposed within the process chamber; The first carrying platform and the second carrying platform are provided on the driving mechanism, and the driving mechanism is used to drive the first carrying platform and the second carrying platform to move along the first direction and the second direction; The first direction and the second direction are perpendicular to each other, and a moving plane formed by the first direction and the second direction is parallel to both the first bearing surface and the second bearing surface.

4. The dual-station wafer exposure machine according to claim 3, characterized in that: The measuring component includes a first laser measurer and a first image receiver, which are arranged opposite to each other along the first direction. The first laser measurer is used to emit measuring light to the first bearing surface or the second bearing surface, and the first image receiver is used to receive measuring light reflected from the first bearing surface or the second bearing surface.

5. The dual-station wafer exposure machine according to claim 4, characterized in that: The measuring assembly also includes a second laser measurer and a second image receiver, which are arranged opposite to each other along the second direction. The second laser measurer is used to emit measuring light to the first bearing surface or the second bearing surface, and the second image receiver is used to receive measuring light reflected from the first bearing surface or the second bearing surface.

6. The dual-station wafer exposure machine according to claim 5, characterized in that: The measuring assembly further includes a controller electrically connected to the first laser measurer, the first image receiver, the second laser measurer, the second image receiver, and the driving mechanism; When the controller controls the driving mechanism to drive the first carrying surface or the second carrying surface in the measuring chamber to move along a first direction, the controller controls the first laser measuring device and the first image receiver to operate, and controls the second laser measuring device and the second image receiver to shut down; When the controller controls the driving mechanism to drive the first carrying surface or the second carrying surface located in the measuring chamber to move along the second direction, the controller controls the first laser measurer and the first image receiver to turn off, and controls the second laser measurer and the second image receiver to work.

7. The dual-station wafer exposure machine according to claim 6, characterized in that: Also included is a grinding mechanism disposed within the process chamber; The grinding mechanism is electrically connected to the controller, and the grinding mechanism has a grinding head; When the measuring component detects that the protrusion height of the first bearing surface or the second bearing surface is greater than a preset height threshold, the controller controls the grinding head to grind the first bearing surface or the second bearing surface.

8. The dual-station wafer exposure machine according to claim 1, wherein: It also includes a robot arm arranged in the process chamber, and the robot arm is used to transfer the wafer after the exposure process out of the process chamber.

9. The dual-station wafer exposure machine according to claim 5, characterized in that: The first laser measuring device and the second laser measuring device are both 3D line laser sensors.

10. The dual-station wafer exposure machine according to claim 6, wherein: The measuring component also includes an alarm; The alarm is electrically connected to the controller; When the measuring component detects that the protrusion height of the first bearing surface or the second bearing surface is greater than a preset height threshold, the controller feeds back an alarm signal to the alarm, and the alarm sounds an alarm.

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