Optimization And Application Of Wafer Dicing Machine Control System

With the rapid development of the electronic consumer industry,the demand for semiconductor manufacturing equipment is getting higher and higher.As the final process of processing silicon wafer dicing machine has become a key equipment for the semiconductor industry,its cutting performance directly affects the quality and efficiency of the processing chip.Although some companies in China have developed a dicing saw,they still require a certain amount of manual participation when the equipment is put into operation,and the correction of streets wastes much time;currently,it is mainly used for cutting small-size wafers,and when cutting large-size wafers can't guarantee the positioning accuracy;In addition there is instability in the work.In view of the above problems,the paper deeply studied the features and processing methods of the wafer microscopic images,improved the efficiency of street alignment,analyzed the positioning error of the feed axis and the vibration of the working disk rotation,and improved the positioning accuracy and stability of the system.The main research work and results of the thesis are summarized as follows:(1)Analyzed the characteristics of the microscopic image of the wafer,and proposed the second-order central moment method to locate and calculate the directions of the left and right extreme images of the street,and achieved automatic and accurate alignment of the “no marks” wafers;For cutting the wafer with marks,the paper proposes a teaching-recursive method based on template matching algorithm to quickly locate the left and right mark,and achieve efficient and accurate alignment.(2)A full-closed feed control system is constructed by installing a grating,the feed positioning error data of the Y-axis is collected,and the error trend is analyzed.The back-propagation neural network algorithm is used to train the positioning error data,and a positioning error is established.The prediction and compensation model.The experimental verification of the revised positioning error from the original ± 20um/100 mm to ± 5um/100 mm.(3)For the phenomenon of jitter and position overshoot caused by DD motor under variable load conditions,this paper studies the time-varying and nonlinear problems in the motor drive control,introduces the fuzzy PID intelligent control algorithm,and realizes the self-tuning of the system parameters.Improves stability during DD motor positioning.The developed wafer cutting equipment has been put into trial operation,and the "one-click" automatic alignment of the wafer streets has been achieved,which has significantly reduced the amount of manual intervention.The accuracy of the spindle skipping positioning in the process of cutting has been improved significantly than that in the semi-closed loop mode;then a stable and reliable positioning movement of the DD motor under different working discs is achieved.Trial cut wafers have a significant increase in cutting accuracy and yield.