High-precision high-speed mounting force control system and method

Abstract

The present application relates to the technical fields of semiconductor chip mounting force control, in particular to a high-precision and high-speed mounting force control system and method, comprising a mounting machine and an upper computer connected by communication, the mounting machine is provided with a mounting module, the mounting module comprises a servo motor and a mounting suction nozzle, the mounting suction nozzle comprises a mounting elastic body, both ends of the mounting elastic body are respectively provided with encoders, the encoders are used for detecting the elastic deformation of both ends of the mounting elastic body and converting into electric signals, the encoders are connected with a force control processing module arranged in the upper computer, the force control processing module comprises an MCU assembly and a subtraction calculator, the force control processing module is electrically connected with the servo motor, the force control processing module receives the electric signals of the encoders, analyzes the stress of the mounting elastic body and adjusts the output torque of the servo motor. The present application adopts a full-closed loop control mode, can reduce the calculation amount of MCU and improve the signal processing speed.

Description

Technical Field

[0001] This invention relates to the field of semiconductor chip mounting force control technology, and in particular to a high-precision, high-speed mounting force control system and method. Background Technology

[0002] In the semiconductor chip packaging and testing process, the force control of the soldering head is a critical step. Because the chip itself is small, precise force is required for picking up and placing the chip. Too much force will damage the chip, while too little force will result in the chip not being firmly gripped. Therefore, high-precision force control is needed to avoid damaging the chip during picking up and placing.

[0003] Currently, the industry commonly uses force control sensors for detection. The welding nozzle obtains data by touching the force sensor, which is then filtered and transmitted to the A / D converter to obtain the result, which is fed back to the host computer to control the output torque. The principle of this measurement is that the nozzle presses down on the pressure sensor, which senses the force caused by the deformation of the metal surface, calculates the specific value, and then transmits it to the A / D converter through a filter to obtain the value.

[0004] However, the above-mentioned existing technical solutions have the following drawbacks: Since the pressure sensor cannot directly output force data, the MCU needs to filter and perform A / D conversion on the signal output by the pressure sensor before it can be used as an output signal. The MCU has a large amount of computational workload, and the intermediate data processing is long, resulting in slow transmission speed and affecting the final placement cycle. In addition, during the process of the welding head pressing down on the surface, the metal deforms at an angle, and the deformation on both sides is different. The existing single-sided pressure sensor solution can only obtain deformation data at one point, and the accuracy of the force data obtained is not high enough. Summary of the Invention

[0005] The purpose of this invention is to provide a high-precision, high-speed mounting force control system and method to solve the problems existing in the prior art.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A high-precision, high-speed placement force control system includes a placement machine and a host computer connected by communication. The placement machine is equipped with a placement module, which includes a servo motor and a placement nozzle. The placement nozzle includes a placement elastomer, which serves as a connector between the servo motor and the nozzle. Encoders are mounted at both ends of the elastomer; these encoders are either incremental or absolute encoders. The encoders detect the elastic deformation at both ends of the elastomer and convert it into electrical signals, outputting force data. The encoders can directly output numerical data without additional signal processing steps. The encoders are connected to a force control processing module in the host computer. The force control processing module includes an MCU component and a subtraction calculator. The force control processing module is electrically connected to the servo motor. It receives the electrical signals from the encoders, analyzes the force on the elastomer, and adjusts the output torque of the servo motor. The system also includes a distance sensor connected to the force control processing module, which is used to acquire the movement distance of the placement nozzle. The force control processing module directly calculates the difference between the numerical data output by the encoder to obtain the actual force value, establishes a two-dimensional coordinate relationship between the moving distance of the mounting nozzle and the actual force value, and defines an effective action range. When the two-dimensional vector composed of the moving distance of the mounting nozzle and the actual force value falls within the effective action range, force control processing begins.

[0007] By adopting the above technical solution, an encoder is added to each end of the mounted elastomer. During the detection process, the encoder can quickly and directly obtain the value. The difference between the two values ​​can be used to obtain the final value, which is convenient, fast and accurate.

[0008] By adopting the above technical solution, the movement distance of the mounting nozzle is further considered in the force control system to avoid incorrect judgment caused by excessive force due to cable or air resistance during the nozzle's descent.

[0009] In a further embodiment, the selection range of the effective action interval is: x1≤X≤x2, y1≤Y≤y2.

[0010] A high-precision, high-speed placement force control method, applied to the aforementioned high-precision, high-speed placement force control system, includes the following steps: Step S1: Install encoders at both ends of the mounted elastomer. The encoders collect the deformation at both ends of the mounted elastomer and output electrical signals. The output electrical signals are the force values ​​at both ends of the mounted elastomer. Step S2: Calculate the difference between the force values ​​at both ends of the attached elastomer, and the obtained difference data is the actual force value of the attached elastomer; Step S3: Set up a distance measuring sensor to obtain the moving distance of the mounting nozzle, and establish a two-dimensional coordinate relationship between the moving distance and the actual force value, with the moving distance as the X-axis and the actual force value as the Y-axis. Step S4: Define the effective action range. Select a box in the two-dimensional coordinate system established in step S3. The selection range is: x1≤X≤x2, y1≤Y≤y2. The two-dimensional vector composed of the moving distance of the mounting nozzle and the actual force value falls within the effective action range, and the force control processing module starts to perform force control processing.

[0011] In summary, the present invention has the following beneficial effects: 1. The present invention provides a high-precision and high-speed mounting force control system and method, which adopts a fully closed-loop control method and uses dual encoders to collect the deformation of the elastomer, thereby reducing the computational load of the MCU and improving the signal processing speed; 2. The present invention provides a high-precision and high-speed mounting force control system and method, which, by setting up dual encoders in conjunction with movement distance detection, can eliminate interference errors caused by cables, wind resistance, and the elastomer itself, thereby improving the accuracy of force control. Attached Figure Description

[0012] Figure 1 This is a system structure diagram of a high-precision, high-speed mounting force control system according to the present invention; Figure 2 This is a flowchart illustrating the steps of a high-precision, high-speed mounting force control method according to the present invention. Figure 3 This is a two-dimensional coordinate diagram of step S3 in the high-precision and high-speed mounting force control method of the present invention. Detailed Implementation

[0013] The present invention will be further described in detail below with reference to the accompanying drawings.

[0014] Identical parts are indicated by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to the attached figures. Figure 1In this specification, the terms "bottom surface" and "top surface," "inner" and "outer" refer to the direction toward or away from the geometry of a specific component. 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 specification, "a plurality of" means two or more, unless otherwise explicitly and specifically defined by the direction of the center.

[0015] Example: like Figure 1 As shown, this embodiment provides a high-precision and high-speed mounting force control system. The system is applied in semiconductor chip mounting and packaging testing and is used to solve the problems of low mounting force control accuracy and large error in the prior art.

[0016] To address the problems of the prior art, this embodiment adopts the following design: The system includes a placement machine and a host computer connected by communication. The placement machine is equipped with a placement module, which includes a servo motor and a placement nozzle. The placement nozzle includes a placement elastomer, and encoders are installed at both ends of the placement elastomer. The encoders are connected to a force control processing module in the host computer. The force control processing module includes an MCU component and a subtraction calculator. The force control processing module is electrically connected to the servo motor. The force control processing module receives the electrical signals from the encoders, analyzes the force on the placement elastomer, and adjusts the output torque of the servo motor.

[0017] In this embodiment, the mounting elastomer is a connecting component to the mounting nozzle, which can be a connection between a servo motor and the mounting nozzle. The encoder is used to detect the elastic deformation at both ends of the mounting elastomer and convert it into an electrical signal. The output electrical signal is the force data. By adding an encoder to each end of the mounting elastomer, the encoder can quickly and directly obtain values ​​during the detection process. Subtracting the values ​​at both ends yields the final value, which is convenient, fast, and accurate.

[0018] In a further embodiment, the encoder can be selected according to actual needs. The purpose of setting the encoder is to be able to directly output numerical data without additional signal processing steps. Therefore, the encoder can be selected according to the output signal method. The selected encoder needs to ensure that the encoder accuracy is high enough to avoid errors caused by insufficient encoder accuracy. The encoder is one of incremental encoder and absolute encoder.

[0019] In a further embodiment, the system further includes a ranging sensor connected to the force control processing module, the ranging sensor being used to acquire the moving distance of the mounting nozzle.

[0020] By adopting the above technical solution, the movement distance of the mounting nozzle can be further considered in the force control system, avoiding incorrect judgment caused by excessive force due to cable or air resistance during the nozzle's descent.

[0021] This embodiment also provides a high-precision, high-speed placement force control method, applied to the aforementioned high-precision, high-speed placement force control system. The method includes the following steps: Step S1: Install encoders at both ends of the mounted elastomer. The encoders collect the deformation at both ends of the mounted elastomer and output electrical signals. The output electrical signals are the force values ​​at both ends of the mounted elastomer. Step S2: Calculate the difference between the force values ​​at both ends of the attached elastomer, and the obtained difference data is the actual force value of the attached elastomer; Step S3: Set up a distance measuring sensor to obtain the moving distance of the mounting nozzle, and establish a two-dimensional coordinate relationship between the moving distance and the actual force value, with the moving distance as the X-axis and the actual force value as the Y-axis. Step S4: Define the effective action range. Select a box in the two-dimensional coordinate system established in step S3. The selection range is: x1≤X≤x2, y1≤Y≤y2. The two-dimensional vector composed of the moving distance of the mounting nozzle and the actual force value falls within the effective action range, and the force control processing module starts to perform force control processing.

[0022] In the embodiments disclosed in this invention, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments disclosed in this invention according to the specific circumstances.

[0023] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A high-precision, high-speed placement force control system, the system comprising a placement machine and a host computer connected by communication, the placement machine being equipped with a placement module, the placement module comprising a servo motor and a placement nozzle, characterized in that: The mounting nozzle includes a mounting elastomer, which serves as a connector between the servo motor and the mounting nozzle. Encoders are mounted at both ends of the mounting elastomer; these encoders are either incremental or absolute encoders. The encoders detect the elastic deformation at both ends of the mounting elastomer and convert it into electrical signals, outputting force data. The encoders can directly output numerical data without additional signal processing steps. The encoders are connected to a force control processing module in the host computer. The force control processing module includes an MCU component and a subtraction calculator. The force control processing module is electrically connected to the servo motor. It receives the electrical signals from the encoders, analyzes the force on the mounting elastomer, and adjusts the output torque of the servo motor. The system also includes a distance sensor connected to the force control processing module, which is used to acquire the movement distance of the mounting nozzle. The force control processing module directly calculates the difference between the numerical data output by the encoder to obtain the actual force value, establishes a two-dimensional coordinate relationship between the moving distance of the mounting nozzle and the actual force value, and defines an effective action range. When the two-dimensional vector composed of the moving distance of the mounting nozzle and the actual force value falls within the effective action range, force control processing begins.

2. The high-precision, high-speed mounting force control system according to claim 1, characterized in that: The effective action range is defined as follows: x1≤X≤x2, y1≤Y≤y2, where X represents the X-axis of the two-dimensional relational coordinates and Y represents the Y-axis of the two-dimensional relational coordinates.

3. A high-precision, high-speed placement force control method, applied to the high-precision, high-speed placement force control system according to any one of claims 1-2, characterized in that, Includes the following steps: Step S1: Install encoders at both ends of the mounted elastomer. The encoders collect the deformation at both ends of the mounted elastomer and output electrical signals. The output electrical signals are the force values ​​at both ends of the mounted elastomer. Step S2: Calculate the difference between the force values ​​at both ends of the attached elastomer, and the obtained difference data is the actual force value of the attached elastomer; Step S3: Set up a distance measuring sensor to obtain the moving distance of the mounting nozzle, and establish a two-dimensional coordinate relationship between the moving distance and the actual force value, with the moving distance as the X-axis and the actual force value as the Y-axis. Step S4: Define the effective action range. Select a box in the two-dimensional coordinate system established in step S3. The selection range is: x1≤X≤x2, y1≤Y≤y2. The two-dimensional vector composed of the moving distance of the mounting nozzle and the actual force value falls within the effective action range, and the force control processing module starts to perform force control processing.

Images