Method for laser-assisted adjustment of verticality of installation reference surface

Abstract

The invention discloses a method for laser-assisted adjustment of the perpendicularity of a mounting reference surface. The method comprises the following steps that 1, a laser emitting device and a reflecting device are arranged on the same operation surface; step 2, using a laser emitting device to emit laser to a reflecting device, enabling the laser to be parallel to the operation surface, enabling the laser to be reflected by the reflecting device to form reflected light, and enabling the reflected light to be perpendicular to the laser through the reflecting device; 3, the camera is installed on the fixing frame through a moving mechanism, and the reflecting device is moved until the reflected light forms a light spot in the imaging center of the camera; 4, moving the camera back and forth up and down, and observing whether the light spot is always located at the imaging center of the camera; if yes, judging that the installation is correct; and if not, judging that the installation is abnormal. The invention provides a perfect and intuitive method to verify the perpendicularity of the camera at the mounting reference surfaces at various heights, so that the camera is ensured to be correctly mounted, and the subsequent mounting precision is further ensured.

Description

Technical Field

[0001] The present application relates to the field of semiconductor mounting, and in particular to a method for laser-assisted adjustment of the verticality of a mounting reference surface. Background Art

[0002] In the semiconductor industry, placement technology is one of the key processes to achieve the connection between chips and substrates. With the continuous development of semiconductor technology, the requirements for placement accuracy and efficiency are getting higher and higher. Semiconductor automated placement equipment plays a vital role in this process. Among them, cameras, as the core components of the visual inspection system, are crucial to ensure placement accuracy.

[0003] Semiconductor automated placement equipment usually includes components such as a rack, a gantry system, a wafer loading mechanism, a placement head, a glue coating system, a sensing and detection system, and a substrate conveying system. In these systems, cameras are used to capture the marking points on the chip and the substrate to achieve precise positioning and alignment. However, the cameras used in existing semiconductor automated placement devices usually have a very small depth of field, and the camera lens usually cannot be zoomed. This is mainly due to the cost factor of the camera. Due to the limitations of such cameras, the relative distance between the camera lens and the chip must be fixed to ensure the imaging effect of the chip. However, when the chip thickness changes or the fixture height changes, the relative distance between the camera lens and the chip will change. Therefore, the height of the camera needs to change with the actual situation to ensure the clarity of the captured image, thereby ensuring the accuracy of subsequent placement.

[0004] At the same time, the captured chip image needs to be used as a reference for subsequent mounting, so it is necessary to ensure that the camera axis is perpendicular to the operating surface parallel to the chip to ensure the subsequent mounting accuracy. In order to facilitate judgment and description, a mounting reference plane is defined. The mounting reference plane is always parallel to the camera axis. Therefore, the mounting reference plane needs to be always 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 a camera, it is usually the operator who subjectively judges whether the camera is installed correctly through observation. The operator cannot guarantee the verticality of the camera's installation reference surface at the initial position and after the camera's height is changed. Therefore, in the current production environment related to placement, there is a lack of a complete method to verify the verticality of the camera's installation reference surface at various heights, thereby ensuring the subsequent placement accuracy. Summary of the invention

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

[0007] In order to solve the above technical problems, the present application provides a method for laser-assisted adjustment of the verticality of the installation reference surface, comprising the following steps: Step 1: Place the laser emitting device and the reflecting device on the same operating surface; Step 2, using the laser emitting device to emit laser light to the reflecting device, and making the laser light parallel to the operation surface, the laser light is reflected by the reflecting device to form reflected light, and the reflected light is made perpendicular to the laser light by the reflecting device; Step 3, the camera is mounted on a fixed frame by a moving mechanism, and the reflecting device is moved until the reflected light forms a light spot at the imaging center of the camera, wherein the fixed frame refers to a mechanism for fixing the moving mechanism, and the fixed frame may also refer to a component in a semiconductor automated placement device that can fix the moving mechanism; Step 4: Move the camera up and down and back and forth, and observe whether the light spot is always located at the imaging center of the camera; if so, it is determined that the installation is correct; if not, it is determined that the installation is abnormal.

[0008] Preferably, installing the camera on the fixed frame through the moving mechanism includes installing the camera on the fixed frame through 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, the starting end indicates the topmost end that the camera can move to, and the ending end indicates the tailmost end that the camera can move to.

[0009] Preferably, making the reflected light perpendicular to the laser by a reflection device includes making the angle between the reflection surface of the reflection device and the operation surface 45°, and making the laser coplanar with the axis of the camera.

[0010] Preferably, determining that there is an installation abnormality includes determining that there is an abnormality in the installation of the moving mechanism or the camera, adjusting the moving mechanism or the camera, and repeating step 4.

[0011] Preferably, determining that there is an installation abnormality includes determining that there are abnormalities in the installation of both the moving mechanism and the camera, adjusting the moving mechanism and the camera respectively, and repeating step 4.

[0012] One or more technical solutions provided in this application have at least the following technical effects or advantages: The reflected light formed by the laser and the reflective device is compared with the imaging center of the camera. At the same time, by moving the camera up and down and observing whether the light spot is always located in the imaging center of the camera, it is possible to determine whether there is any abnormality in the installation of the camera. This makes it possible to easily and intuitively verify the verticality of the installation reference surface of the camera at various heights, and provide timely feedback on the installation status of the camera through the positional relationship between the light spot and the imaging center of the camera, indicating any installation abnormalities. This obviously provides a guarantee for the correct installation of the camera, and is also conducive to ensuring the subsequent mounting accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 is a schematic diagram of the correct installation of the camera provided in the embodiment of the present application; Figure 2 is a schematic diagram of an abnormal guide rail when installing a camera provided in an embodiment of the present application; Figure 3 It is a schematic diagram of a camera abnormality when the camera provided in an embodiment of the present application is installed. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described in the present application are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0016] The method for adjusting the verticality of the installation reference surface with laser assistance comprises the following steps: Step 1: placing a laser emitting device and a reflecting device on the same operating surface (such as a marble platform), wherein the reflecting device includes a reflecting mirror; Step 2, using the laser emitting device to emit laser light to the reflecting device, and making the laser light parallel to the operation surface, the laser light is reflected by the reflecting device to form reflected light, and the reflected light is made perpendicular to the laser light by the reflecting device; Among them, making the reflected light perpendicular to the laser by the reflection device includes making the angle between the reflection surface of the reflection device and the operating surface 45°, making the reflection surface of the reflection device the reflection surface of the reflection mirror, and making the laser coplanar with the axis of the camera.

[0017] Step 3, the camera is mounted on the fixed frame by a moving mechanism, and the reflecting device is moved until the reflected light forms a spot at the imaging center of the camera, the moving mechanism can move the camera up and down, the moving mechanism includes a guide rail, and the up and down movement of the camera can be manually controlled by the guide rail, and the guide rail can also be an electric guide rail that can move automatically, and the electric guide rail can control the automatic movement of the camera in the up and down direction through an electrical signal, and the fixed frame can be an independent mechanism for fixing the moving mechanism, and the fixed frame can also be a component in the semiconductor automatic placement equipment that can fix the moving mechanism; Among them, installing the camera on the fixed frame through the moving mechanism includes installing the camera on the fixed frame through the moving mechanism, and moving the camera to the extreme position of the moving mechanism, and the extreme position is the starting end or the ending end of the moving mechanism. The starting end indicates the topmost end that the camera can move to, and the ending end indicates the tailmost end that the camera can move to.

[0018] Step 4: Move the camera up and down and back and forth, and observe whether the light spot is always located at the imaging center of the camera; if so, it is determined that the installation is correct; if not, it is determined that the installation is abnormal.

[0019] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the correct installation of the camera. Because the axis of the camera is the axis of the camera lens, the lens represents the camera in the figure, and the guide rail represents the moving mechanism. If the light spot is always located at the imaging center of the camera, the axis of the camera lens must be perpendicular to the operating surface, that is, the installation reference surface is perpendicular to the operating surface, and the guide rail must also be parallel to the installation reference surface, that is, the guide rail is also perpendicular to the operating surface; Determining the installation abnormality includes determining that there is an abnormality in the installation of the moving mechanism or the camera, or determining that there are abnormalities in the installation of both the moving mechanism and the camera, that is, there are three situations that lead to the abnormality. When the installation abnormality is found, at least one of the situations is likely to occur, and then the moving mechanism or the camera is adjusted to solve the actual abnormality, and step 4 is repeated. The purpose of repeating step 4 is to verify whether the abnormality still exists; Please refer to Figure 2 , Figure 2 This is a schematic diagram of the guide rail abnormality when the camera is installed. Figure 2 The lens represents the camera. In this case, the lens is correctly installed on the rail, but the rail is abnormal, that is, the installation of the rail is deviated, so the installation of the rail needs to be adjusted; please refer to Figure 3 , Figure 3 This is a schematic diagram of camera anomalies when the camera is installed. Figure 3 In the figure, the lens represents the camera. At this time, the guide rail is correctly installed on the fixing frame, but the connection between the camera and the guide rail is abnormal, that is, the installation of the camera relative to the guide rail is deviated, so the installation of the camera needs to be adjusted; Both guide rail abnormalities and camera abnormalities belong to installation abnormalities. Installation abnormalities also include situations where both the guide rail and the camera are abnormal. At this time, both the camera and the guide rail need to be adjusted. Determining installation abnormalities is a prompt for abnormal conditions. Abnormal conditions include abnormal installation of the mobile mechanism, abnormal camera installation, and abnormal installation of both the mobile mechanism and the camera. Listing possible abnormal conditions will help to quickly identify the actual cause of the abnormality.

[0020] In summary, the present application provides a complete and intuitive method to verify the verticality of the camera's mounting reference surface at various heights, thereby ensuring that the camera is correctly installed and further ensuring subsequent mounting accuracy.

[0021] It should also be noted that in this specification, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A method for adjusting the verticality of a mounting reference surface with the aid of laser, characterized in that: The steps include: Step 1: Place the laser emitting device and the reflecting device on the same operating surface; Step 2, using the laser emitting device to emit laser light to the reflecting device, and making the laser light parallel to the operation surface, the laser light is reflected by the reflecting device to form reflected light, and the reflected light is made perpendicular to the laser light by the reflecting device; Step 3, installing the camera on the fixed frame by means of a moving mechanism, and moving the reflecting device until the reflected light forms a light spot at the imaging center of the camera; Step 4: Move the camera up and down and back and forth, and observe whether the light spot is always located at the imaging center of the camera; if so, it is determined that the installation is correct; if not, it is determined that the installation is abnormal.

2. The method for adjusting the verticality of the installation reference surface with laser assistance according to claim 1, characterized in that: Installing the camera on the fixed frame through the moving mechanism includes installing the camera on the fixed frame through 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 adjusting the verticality of the installation reference surface with laser assistance according to claim 1, characterized in that: The reflected light is made perpendicular to the laser by a reflection device, including making the angle between the reflection surface of the reflection device and the operation surface 45 degrees, and making the laser and the axis of the camera coplanar.

4. The method for adjusting the verticality of the installation reference surface with laser assistance according to claim 1, characterized in that: Determining the installation abnormality includes determining that there is an abnormality in the installation of the moving mechanism or the camera, adjusting the moving mechanism or the camera, and repeating step 4.

5. The method for adjusting the verticality of the installation reference surface with laser assistance according to claim 1 or 4, characterized in that: Determining the installation abnormality includes determining that both the moving mechanism and the camera are abnormally installed, adjusting the moving mechanism and the camera respectively, and repeating step 4.

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