Mask side wall detection device and etching equipment

Abstract

The utility model belongs to the field of mask plate side wall detection, and particularly relates to a mask plate side wall detection device and etching equipment, the mask plate side wall detection device comprises a rotatable sample table, a laser, a first camera, a second camera and a lifting mechanism; the rotatable sample table is used for supporting a mask plate and driving the mask plate to rotate; the laser is used for generating laser points; the first camera is used for shooting the side wall of the mask pattern from a first direction so as to obtain coordinate positions of a laser point in the X-axis direction and the Z-axis direction; the second camera is used for shooting the side wall of the mask pattern from a second direction so as to obtain the coordinate positions of the laser point in the Y-axis direction and the Z-axis direction; the lifting mechanism is used for driving the laser to reciprocate in the Z-axis direction. Compared with a scanning electron microscope or an optical microscope which can only obtain two-dimensional plane information, the three-dimensional shape measuring device provided by the utility model provides real-time three-dimensional shape data for the etching process, and effectively solves the problem of over-etching or under-etching.

Description

Technical Field

[0001] This utility model belongs to the field of mask sidewall inspection, and particularly relates to a mask sidewall inspection device and etching equipment. Background Technology

[0002] The inspection of mask sidewalls mainly relies on two-dimensional planar inspection techniques, such as scanning electron microscopy (SEM) or optical microscopy. While these techniques can achieve high-resolution observation, they only provide two-dimensional planar information and cannot timely acquire three-dimensional sidewall geometric features, such as sidewall tilt angles, roughness, and microgrooves. Due to the lack of accurate understanding of the three-dimensional sidewall morphology, it is difficult to precisely and dynamically control the etching degree during the etching process, which can easily lead to undercut or footing of the sidewalls. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a mask sidewall detection device, which aims to solve the problem of not being able to obtain three-dimensional sidewall geometric features in a timely manner.

[0004] A mask sidewall detection device is installed on the machine base of an etching equipment. The mask sidewall detection device includes a rotatable sample stage, a laser, a first camera, a second camera, and a lifting mechanism.

[0005] The rotatable sample stage is used to support the mask and to drive the mask to rotate about a rotation axis parallel to the Z-axis.

[0006] The laser is used to generate laser spots that are directed toward the sidewalls of the mask.

[0007] The first camera is used to capture images of the mask pattern sidewall from a first direction to obtain the coordinate positions of the laser point along the X-axis and Z-axis.

[0008] The second camera is used to capture images of the mask pattern sidewall from a second direction to obtain the coordinate positions of the laser point along the Y-axis and Z-axis, wherein the first direction and the second direction are staggered.

[0009] The lifting mechanism is used to drive the laser to reciprocate along the Z-axis.

[0010] Optionally, the first direction is the Y-axis direction, and the second direction is the X-axis direction.

[0011] Optionally, it also includes a mounting frame installed on the machine tool, the mounting frame including a first crossbar and a second crossbar;

[0012] The first camera is mounted on the first crossbar and its position can be adjusted along the X-axis.

[0013] The second camera is mounted on the second crossbar and its position can be adjusted along the Y-axis.

[0014] Optionally, the first crossbar is provided with a plurality of spaced first connecting structures along the X-axis direction, and the first camera is detachably connected to the first connecting structure;

[0015] And / or, the second crossbar is provided with a plurality of spaced second connecting structures along the Y-axis direction, and the second camera is detachably connected to the second connecting structure.

[0016] Optionally, both the first and second horizontal connecting rods are connected to the machine tool via at least one vertical connecting rod.

[0017] Optionally, the vertical connecting rod is detachably connected to the machine base.

[0018] Optionally, a mounting base may also be included;

[0019] The laser is mounted on the mounting base and its orientation relative to the mounting base is adjustable;

[0020] The lifting mechanism is used to drive the mounting base to reciprocate along the Z-axis.

[0021] Optionally, the mounting base and the laser are connected by a multi-joint connection structure.

[0022] Optionally, the rotatable sample stage can be raised and lowered along the Z-axis.

[0023] This invention also provides an etching apparatus, including the mask sidewall detection device described above.

[0024] Compared to scanning electron microscopes or optical microscopes that can only acquire two-dimensional planar information, this device provides real-time three-dimensional morphological data for the etching process through a three-dimensional spatial layout, effectively solving the problems of over-etching or under-etching, and significantly improving the comprehensiveness and accuracy of mask sidewall inspection in semiconductor manufacturing. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of the mask sidewall detection device provided in this embodiment of the utility model.

[0027] Explanation of icon numbers:

[0028] label name label name 100 Rotatable sample stage 200 laser 310 First camera 320 Second camera 410 First crossbar 420 Second crossbar 500 Vertical connecting rod 600 machine Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0030] This utility model embodiment provides a mask sidewall detection device, which is installed on the machine base 600 of an etching equipment.

[0031] Please see Figure 1 The mask sidewall detection device includes a rotatable sample stage 100, a laser 200, a first camera 310, a second camera 320, and a lifting mechanism (not shown in the figure).

[0032] The rotatable sample stage 100 is used to support the mask and to drive the mask to rotate about a rotation axis parallel to the Z-axis.

[0033] Laser 200 is used to generate laser spots that are directed toward the sidewalls of the mask;

[0034] The first camera 310 is used to capture images of the mask pattern sidewall from a first direction to obtain the coordinate positions of the laser point along the X-axis and Z-axis.

[0035] The second camera 320 is used to capture images of the mask pattern sidewall from a second direction to obtain the coordinate positions of the laser points along the Y-axis and Z-axis, wherein the first direction and the second direction are staggered.

[0036] The lifting mechanism is used to drive the laser 200 to move back and forth along the Z-axis.

[0037] Based on this invention, during use, laser 200 first emits a laser beam, which is precisely directed towards the sidewall of the mask, forming a clearly visible laser point on the sidewall. This laser point serves as a key marker for subsequent three-dimensional coordinate measurements. Next, the first camera 310 captures an image of the mask sidewall from a specific first direction, obtaining the coordinate positions of the laser point along the X and Z axes based on optical imaging principles and pre-calibrated coordinate system parameters. Simultaneously, the second camera 320 captures an image from a second direction, using the same measurement logic to obtain the coordinate positions of the laser point along the Y and Z axes. Utilizing the triangulation principle of binocular vision, based on parameters such as the shooting angle, focal length, and optical axis spacing of the two cameras, the coordinates (X, Y, Z) of the laser point in three-dimensional space can be accurately calculated.

[0038] Subsequently, the rotatable sample stage 100 begins operation, driving the mask to rotate smoothly around a rotation axis parallel to the Z-axis. During rotation, at each selected angle, i.e., at each different angular position, the coordinates of the laser point formed by the laser 200 can be acquired by the dual cameras, thereby obtaining multiple three-dimensional coordinates of the outer periphery of a horizontal section of the mask. By acquiring and processing these discrete coordinate points, the shape contour of the outer periphery of the horizontal section of the mask can be accurately constructed. The lifting mechanism plays a crucial role in the vertical scanning process. It drives the laser 200 to move linearly along the Z-axis. During the movement, the steps of laser point projection, coordinate acquisition, and section construction are repeated, gradually covering different height areas of the mask, and finally integrating the information of the outer periphery of each horizontal section to construct the three-dimensional morphology of the entire sidewall of the mask.

[0039] Compared to scanning electron microscopes or optical microscopes that can only acquire two-dimensional planar information, this device provides real-time three-dimensional morphological data for the etching process through the precise coordination of spatial three-dimensional layout and motion relationships. It effectively solves the problems of over-etching or under-etching, and significantly improves the comprehensiveness and accuracy of mask sidewall inspection in semiconductor manufacturing.

[0040] In this embodiment of the invention, the first direction is the Y-axis direction, and the second direction is the X-axis direction. The orthogonal layout simplifies the calibration process of the first camera 310 and the second camera 320, reduces the difficulty of equipment debugging, and facilitates subsequent data docking with the motion control module of the etching equipment to achieve real-time linkage between detection data and etching parameters.

[0041] In this embodiment of the utility model, the mask sidewall detection device further includes a mounting frame installed on the machine base 600, and the mounting frame includes a first crossbar 410 and a second crossbar 420.

[0042] The first camera 310 is mounted on the first crossbar 410 and its position can be adjusted along the X-axis.

[0043] The second camera 320 is mounted on the second crossbar 420 and its position can be adjusted along the Y-axis.

[0044] The first horizontal connecting rod 410 extends along the X-axis, and the second horizontal connecting rod 420 extends along the Y-axis, forming a cross-shaped two-dimensional adjustment frame. This allows the first camera 310 and the second camera 320 to be translated along the X-axis and Y-axis respectively, enabling flexible adjustment of the shooting field of view. This adjustable structural design significantly improves the versatility and adaptability of the device: for masks of different sizes, the shooting range can be adjusted by translating the cameras to ensure that the laser point is always in the center of the lens's field of view; for side wall features at different locations (such as edge areas or center areas), dynamic calibration of the coordinate position can avoid detection blind spots caused by viewing angle shifts.

[0045] In this embodiment of the utility model, the first horizontal connecting rod 410 is provided with a plurality of first connecting structures spaced apart along the X-axis direction, and the first camera 310 is detachably connected to the first connecting structures.

[0046] In this embodiment of the utility model, the second crossbar 420 is provided with a plurality of spaced second connecting structures along the Y-axis direction, and the second camera 320 is detachably connected to the second connecting structures.

[0047] The first camera 310 and the second camera 320 can be detachably installed in different locations.

[0048] When inspecting large-area masks, the camera can be mounted at the far end of the crossbar to expand the field of view; when inspecting local fine structures, the camera can be moved to the near end to improve the imaging resolution.

[0049] In this embodiment of the invention, both the first horizontal connecting rod 410 and the second horizontal connecting rod 420 are connected to the machine base 600 via at least one vertical connecting rod 500. The height of the vertical connecting rod 500 can be customized according to the frame size so that the installation height of the horizontal connecting rod matches the center height of the rotatable sample stage 100, ensuring that the optical axis of the camera maintains the optimal detection angle with the side wall of the mask.

[0050] In this embodiment of the invention, the vertical connecting rod 500 is detachably connected to the machine base 600, such as by bolt connection or quick-release buckle, allowing the vertical connecting rod 500 to be quickly disassembled or its position adjusted as needed. When it is necessary to inspect the internal components of the machine base 600 or replace the mask transmission mechanism, the vertical connecting rod 500 can be quickly disassembled, avoiding operational inconvenience caused by the mounting bracket obstructing the view. When changing to different models of etching equipment, by adjusting the installation position of the vertical connecting rod 500, the device can be adapted to different machine bases 600 without redesigning the entire mounting bracket.

[0051] In this embodiment of the utility model, a mounting base is also included;

[0052] The laser 200 is mounted on a mounting base and its orientation relative to the mounting base is adjustable;

[0053] The lifting mechanism is used to drive the mounting base to reciprocate along the Z-axis.

[0054] The adjustable orientation design solves the problem of adapting the laser projection angle to different mask sidewall tilt angles. The orientation adjustment of the laser 200 enables full-area detection of sidewalls with complex topography (such as structures with microgrooves or protrusions), ensuring that the laser projection direction at each detection point is perpendicular to the local sidewall surface, thus improving the accuracy of 3D coordinate calculation.

[0055] In this embodiment of the utility model, the mounting base and the laser 200 are connected by a multi-joint connection structure. The multi-joint structure allows the laser 200 to be continuously adjusted in three degrees of freedom: pitch, yaw, and roll, thus constructing a three-dimensional free adjustment space for the laser 200.

[0056] In this embodiment of the invention, the rotatable sample stage 100 can be raised and lowered along the Z-axis. Compared to a sample stage with a fixed height, this height-adjustable design solves the problem of detection adaptability caused by inconsistent mask thickness in the prior art. Especially in multi-variety, small-batch production scenarios, it allows for quick switching between the detection of different product specifications without changing hardware, significantly improving the production efficiency and versatility of the equipment.

[0057] This utility model also proposes an etching device, which includes a mask sidewall detection device. The specific structure of the etching device is as described in the above embodiments. Since this etching device adopts all the technical solutions of all the above embodiments, it also has all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0058] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A mask side wall detection device, installed on a machine of an etching apparatus, characterized in that, The mask side wall detection device comprises a rotatable sample table, a laser, a first camera, a second camera and a lifting mechanism. The rotatable sample table is used to support the mask and drive the mask to rotate around a rotation axis parallel to the Z axis. The laser is used to generate a laser spot directed to the side wall of the mask. The first camera is used to capture the side wall of the mask pattern from a first direction to obtain the coordinate positions of the laser spot in the X axis direction and the Z axis direction. The second camera is used to capture the side wall of the mask pattern from a second direction to obtain the coordinate positions of the laser spot in the Y axis direction and the Z axis direction, wherein the first direction and the second direction are staggered. The lifting mechanism is used to drive the laser to reciprocate along the Z axis direction.

2. The reticle sidewall inspection apparatus of claim 1, wherein, The first direction is the Y axis direction, and the second direction is the X axis direction.

3. The reticle sidewall inspection apparatus of claim 1 or 2, wherein The mounting frame mounted on the machine table is also included, and the mounting frame comprises a first cross connecting rod and a second cross connecting rod. The first camera is mounted on the first cross connecting rod and can be adjusted in position along the X axis direction. The second camera is mounted on the second cross connecting rod and can be adjusted in position along the Y axis direction.

4. The reticle sidewall inspection apparatus of claim 3, wherein The first cross connecting rod is provided with a plurality of first connecting structures arranged at intervals along the X axis direction, and the first camera is detachably connected to the first connecting structures. And / or, the second cross connecting rod is provided with a plurality of second connecting structures arranged at intervals along the Y axis direction, and the second camera is detachably connected to the second connecting structures.

5. The reticle sidewall inspection apparatus of claim 3, wherein The first cross connecting rod and the second cross connecting rod are connected to the machine table through at least one vertical connecting rod.

6. The reticle sidewall inspection apparatus of claim 5, wherein, The vertical connecting rod is detachably connected to the machine table.

7. The reticle sidewall inspection apparatus of claim 1, wherein A mounting seat is also included. The laser is mounted on the mounting seat and can be adjusted in posture relative to the mounting seat. The lifting mechanism is used to drive the mounting seat to reciprocate along the Z axis direction.

8. The reticle sidewall inspection apparatus of claim 7, wherein, The mounting seat and the laser are connected through a multi-joint connecting structure.

9. The reticle sidewall inspection apparatus of claim 1, wherein, The rotatable sample table can be lifted along the Z axis direction.

10. An etching apparatus, characterized by, The mask side wall detection device as claimed in any one of claims 1 to 9 is included.

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