Design And Research Of A Wafer Transport Platform Based On Pneumatic Suspension And Ultrasonic Non-contact Drive

With the increasing integration of large-scale integrated circuits,the requirements for silicon wafer size and wafer processing accuracy in the semiconductor industry are increasing.The wafer transport platform is an extremely critical part of wafer fabrication equipment,and the semiconductor industry is increasingly demanding its performance.Semiconductor silicon wafers are extremely demanding in the transportation environment,and anti-static,anti-magnetic fields,high cleanliness and other working conditions must be ensured during transportation.In this paper,a semiconductor wafer transport device based on pneumatic suspension-ultrasonic noncontact drive is proposed to achieve non-contact transport of loads of enormous area and weight.The working principle is that the pneumatic suspension device floats the wafer,the ultrasonic transducer generates traveling waves on the vibration plate,and the wafer in the floating state moves along the traveling wave transmission direction under the action of the traveling wave to realize the non-contact transportation of the semiconductor wafer.First of all,this paper analyzed the theory of pneumatic suspension and ultrasonic non-contact drive.In theoretical analysis part of the pneumatic suspension,the various throttling modes of the pneumatic suspension device were briefly discussed,and the small orifice restrictor was used as the throttling form of the pneumatic suspension device for the suspension transport platform.At the same time,the bearing capacity of the pneumatic suspension device was analyzed,which lays a theoretical foundation for advanced simulation and experiment.In the theoretical analysis section of ultrasonic non-contact drive,this paper analyzed the piezoelectric transducer vibrator and the sound pressure of near-field ultrasonic suspension,and selected the vibration excitation-absorption method as the formation method of the traveling wave of the transport device.At the end of this chapter,dynamics analysis of the traveling wave drive system was carried out.In the next chapter,a combination of formula derivation and simulation analysis was utilized to design the various system components of the non-contact conveyor platform.Firstly,ANSYS(FLUENT)was used to analyze the flow field of the minor orifice restrictor of the air flotation system,and the specific optimized size of the small orifice restrictor was obtained.The next part is the design of the ultrasonic traveling wave drive system.This section was mainly carried out from the structural design of the transducer,the design of the horn and the organizational design of the traveling wave drive system.The fixed position of the piezoelectric transducer in the system was then determined and the impedance matching analysis of the transducer at the receiving end was made to maximize the efficiency of the system.Finally,the overall design of the non-contact transport platform was completed.In the last section,an experimental platform for non-contact transportation system was built,and its suspension drive capability was studied,including experimental research and analysis on various factors such as system carrying capacity and transportation rate affecting non-contact conveying platform,and related conclusions were obtained.