Laser-assisted adjustment method for the perpendicularity of the mounting reference surface

Abstract

This application discloses a method for laser-assisted adjustment of the perpendicularity of a mounting reference surface, comprising the following steps: Step 1, placing a laser emitting device and a reflecting device on the same operating surface; Step 2, emitting a laser beam from the laser emitting device to the reflecting device, ensuring the laser beam is parallel to the operating surface, and reflecting the laser beam to form reflected light, which is then made perpendicular to the laser beam by the reflecting device; Step 3, mounting a camera on a fixed frame using a moving mechanism, and moving the reflecting device until the reflected light forms a spot at the center of the camera's image; Step 4, moving the camera up and down while observing whether the spot remains at the center of the camera's image; if so, the installation is considered correct; otherwise, the installation is considered abnormal. This application provides a comprehensive and intuitive method to verify the perpendicularity of the camera's mounting reference surface at various heights, thereby ensuring the camera is correctly installed and guaranteeing subsequent mounting accuracy.

Description

Technical Field

[0001] This application relates to the field of semiconductor mounting, and more particularly to a method for laser-assisted adjustment of the perpendicularity of a mounting reference surface. Background Technology

[0002] In the semiconductor industry, chip mounting technology is one of the key processes for connecting chips to substrates. With the continuous development of semiconductor technology, the requirements for mounting accuracy and efficiency are becoming increasingly stringent. Automated semiconductor mounting equipment plays a crucial role in this process, with the camera, as the core component of the vision inspection system, being essential for ensuring mounting accuracy.

[0003] Semiconductor automated placement equipment typically comprises a rack, gantry system, wafer loading mechanism, placement head, adhesive application system, sensing and inspection system, and substrate transport system. In these systems, cameras are used to photograph the markings on the chip and substrate for precise positioning and alignment. However, cameras used in existing semiconductor automated placement equipment often suffer from a very shallow depth of field, and their lenses are typically non-zoomable. This is primarily due to cost considerations; with such cameras, the relative distance between the camera lens and the chip must be fixed to ensure accurate chip imaging. However, changes in chip thickness or fixture height will alter this relative distance. Therefore, the camera height needs to be adjusted according to these changes to ensure clear images and thus guarantee the accuracy of subsequent placement.

[0004] Meanwhile, the captured chip image needs to be used as a reference for subsequent mounting. Therefore, it is necessary to ensure that the camera axis is perpendicular to the operating surface parallel to the chip to guarantee the subsequent mounting accuracy. For ease of judgment and description, a mounting reference surface is defined. This mounting reference surface is always parallel to the camera axis. Therefore, the mounting reference surface must always be perpendicular to the operating surface (such as a marble platform) to ensure that the camera is always in the correct position.

[0005] In actual production, when installing or replacing cameras, operators usually rely on subjective observation to judge whether the installation is correct. Operators cannot guarantee the perpendicularity of the camera to the mounting reference surface in its initial position and after the camera changes height. Therefore, in the current production environment related to mounting, there is a lack of a complete method to verify the perpendicularity of the camera to the mounting reference surface at various heights, thereby ensuring the subsequent mounting accuracy. Summary of the Invention

[0006] The purpose of this application is to provide a laser-assisted method for adjusting the perpendicularity of the mounting reference surface to verify the perpendicularity of the camera at various heights, thereby ensuring that the camera is correctly mounted and thus guaranteeing subsequent mounting accuracy. The mounting reference surface is an abstract surface parallel to the camera axis.

[0007] To address the aforementioned technical problems, this application provides a method for laser-assisted adjustment of the perpendicularity of the mounting reference surface, comprising the following steps:

[0008] Step 1: Place the laser emitting device and the reflecting device on the same operating surface;

[0009] Step 2: Use the laser emitting device to emit a laser towards the reflecting device, and make the laser parallel to the operating surface. The laser is reflected by the reflecting device to form reflected light, and the reflecting device makes the reflected light perpendicular to the laser.

[0010] Step 3: Install the camera on the fixed frame using the moving mechanism, and move the reflecting device until the reflected light forms a light spot at the center of the camera image. The fixed frame refers to a mechanism used to fix the moving mechanism. The fixed frame can also refer to a component in the semiconductor automated placement equipment that can fix the moving mechanism.

[0011] Step 4: Move the camera up and down while observing whether the light spot is always located in the center of the camera's image; if so, the installation is correct; if not, the installation is abnormal.

[0012] Preferably, mounting the camera on the fixed frame via the moving mechanism includes mounting the camera on the fixed frame via the moving mechanism and moving the camera to the extreme position of the moving mechanism. The extreme position is the starting end or the ending end of the moving mechanism. The starting end means the highest point that the camera can move to, and the ending end means the lowest point that the camera can move to.

[0013] Preferably, the reflected light is made perpendicular to the laser by means of a reflecting device, wherein the angle between the reflecting surface of the reflecting device and the operating surface is 45°, and the laser is coplanar with the axis of the camera.

[0014] Preferably, determining an installation abnormality includes determining that the installation of the moving mechanism or camera is abnormal, adjusting the moving mechanism or camera, and repeating step 4.

[0015] Preferably, determining an installation abnormality includes determining that both the moving mechanism and the camera are installed abnormally, adjusting the moving mechanism and the camera respectively, and repeating step 4.

[0016] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0017] By comparing the reflected light generated by the laser and reflective device with the imaging center of the camera, and by moving the camera up and down and observing whether the light spot is always in the imaging center of the camera, it is possible to determine whether there is any abnormality in the installation of the camera. This allows for a simple and intuitive verification of the verticality of the installation reference surface of the camera at various heights. The positional relationship between the light spot and the imaging center of the camera provides timely feedback on the installation status of the camera and indicates any installation abnormalities. This obviously provides a guarantee for the correct installation of the camera, and in turn, helps to ensure the subsequent mounting accuracy. Attached Figure Description

[0018] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram illustrating the correct installation of the camera provided in the embodiments of this application;

[0020] Figure 2 This is a schematic diagram illustrating an abnormality in the guide rail during camera installation, as provided in an embodiment of this application.

[0021] Figure 3 This is a schematic diagram of a camera malfunction during camera installation, as provided in an embodiment of this application. Detailed Implementation

[0022] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described in this application are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] The method for laser-assisted adjustment of the perpendicularity of the mounting reference surface includes the following steps:

[0024] Step 1: Place the laser emitting device and the reflecting device on the same operating surface (such as a marble platform), wherein the reflecting device includes a reflector;

[0025] Step 2: Use the laser emitting device to emit a laser towards the reflecting device, and make the laser parallel to the operating surface. The laser is reflected by the reflecting device to form reflected light, and the reflecting device makes the reflected light perpendicular to the laser.

[0026] The method of making the reflected light perpendicular to the laser by means of a reflecting device includes making the angle between the reflecting surface of the reflecting device and the operating surface 45°, making the reflecting surface of the reflecting device the reflecting surface of the mirror, and making the laser coplanar with the axis of the camera.

[0027] Step 3: Install the camera on the fixed frame using the moving mechanism, and move the reflecting device until the reflected light forms a light spot at the center of the camera image. The moving mechanism can move the camera up and down. The moving mechanism includes a guide rail, through which the up and down movement of the camera can be manually controlled. The guide rail can also be an automatically moving electric guide rail, which can control the automatic up and down movement of the camera through an electrical signal. The fixed frame can be an independent mechanism for fixing the moving mechanism, or it can be a component in the semiconductor automated placement equipment that can fix the moving mechanism.

[0028] The process of mounting the camera on the fixed frame via the moving mechanism includes mounting the camera on the fixed frame via the moving mechanism and moving the camera to the extreme position of the moving mechanism. The extreme position is the starting end or the ending end of the moving mechanism. The starting end means the highest point that the camera can move to, and the ending end means the lowest point that the camera can move to.

[0029] Step 4: Move the camera up and down while observing whether the light spot is always located in the center of the camera's image; if so, the installation is correct; if not, the installation is abnormal.

[0030] Please refer to the following: Figure 1 , Figure 1 This is a diagram showing the correct installation of a camera. Since the axis of the camera is the same as the axis of the camera lens, the lens represents the camera in the diagram, and the guide rail represents the moving mechanism. If the light spot is always located at the center of the camera's image, then the axis of the camera lens must be perpendicular to the operating surface, that is, the mounting reference surface is perpendicular to the operating surface. At the same time, the guide rail must also be parallel to the mounting reference surface, that is, the guide rail is also perpendicular to the operating surface.

[0031] Determining an installation anomaly includes determining that the installation of the moving mechanism or the camera is abnormal, or that the installation of both the moving mechanism and the camera is abnormal. That is, there are three possible situations that could lead to an anomaly. When an installation anomaly is found, at least one of these situations is likely to occur. Then, the actual anomaly is resolved by adjusting the moving mechanism or the camera, and step 4 is repeated. The purpose of repeating step 4 is to verify whether the anomaly still exists.

[0032] Please refer to the following: Figure 2 , Figure 2 This is a diagram illustrating an abnormality in the guide rail during camera installation. Figure 2The image shows a camera represented by a lens. The lens is correctly mounted on the guide rail, but the guide rail itself is faulty, meaning its installation is misaligned. Therefore, the guide rail needs to be adjusted. Please refer to the relevant documentation. Figure 3 , Figure 3 This is a diagram illustrating a camera malfunction during installation. Figure 3 The lens represents the camera. At this time, the guide rail is correctly installed on the bracket, but there is an abnormality in the connection between the camera and the guide rail, that is, the installation of the camera relative to the guide rail is deviated. Therefore, the installation of the camera needs to be adjusted.

[0033] Both guide rail malfunctions and camera malfunctions fall under the category of installation malfunctions. There are also cases where both the guide rail and camera are malfunctioning, in which case both the camera and the guide rail need to be adjusted. Determining an installation malfunction is a notification that there is an abnormal situation. Abnormal situations include abnormal installation of the moving mechanism, abnormal installation of the camera, and abnormal installation of both the moving mechanism and the camera. Listing the possible abnormal situations helps to quickly troubleshoot the actual cause of the abnormality.

[0034] In summary, this application provides a complete and intuitive method to verify the perpendicularity of the mounting reference surface of the camera at various heights, thereby ensuring that the camera is correctly installed and thus guaranteeing the subsequent mounting accuracy.

[0035] It should also be noted that, in this specification, the terms "comprising," "including," or any other variations thereof are intended to cover a 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.

Claims

1. A method for laser-assisted adjustment of the perpendicularity of an installation reference surface, characterized in that, Includes the following steps: Step 1: Place the laser emitting device and the reflecting device on the same operating surface; Step 2: Use the laser emitting device to emit a laser towards the reflecting device, and make the laser parallel to the operating surface. The laser is reflected by the reflecting device to form reflected light, and the reflecting device makes the reflected light perpendicular to the laser. Step 3: Install the camera onto the fixed frame using the moving mechanism, and move the reflecting device until the reflected light forms a light spot at the center of the camera image; Step 4: Move the camera up and down while observing whether the light spot is always located in the center of the camera's image; if so, the installation is correct; if not, the installation is abnormal.

2. The method for laser-assisted adjustment of the perpendicularity of the mounting reference surface according to claim 1, characterized in that, Mounting a camera onto a fixed frame via a moving mechanism includes mounting the camera onto the fixed frame via the moving mechanism and moving the camera to the extreme position of the moving mechanism, wherein the extreme position is the starting end or the ending end of the moving mechanism.

3. The method for laser-assisted adjustment of the perpendicularity of the mounting reference surface according to claim 1, characterized in that, The reflected light is made perpendicular to the laser by means of a reflective device, wherein the angle between the reflective surface of the reflective device and the operating surface is 45°, and the laser is coplanar with the axis of the camera.

4. The method for laser-assisted adjustment of the perpendicularity of the mounting reference surface according to claim 1, characterized in that, Determining an installation anomaly includes determining that the installation of the moving mechanism or camera is abnormal, adjusting the moving mechanism or camera, and repeating step 4.

5. The method for laser-assisted adjustment of the perpendicularity of the mounting reference surface according to claim 1 or 4, characterized in that, Determining an installation anomaly includes determining that both the moving mechanism and the camera are installed abnormally, adjusting the moving mechanism and the camera respectively, and repeating step 4.

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