Recently, more attentions have been paid on non-contact handling approaches in the field of semiconductor production process, especially the application in wafer. Since the contact handling often leads to damaging and contaminating the products, it is highly desirable to get effective non-contact handling for the improvement of the product quality. Many non-contact methods making use of magnetic, electrostatic, acoustic and pneumatic levitations of a workpiece have been proposed to date. A number of investigations are being made on the pneumatic levitation since it is magnetic free with little heat and can be easily applied to any kind of materials.
The pneumatic levitation is based upon Bernoulli principle. However, this method is known to consume large gas flow rate which can be the cost rise of products. Moreover, the recent trend of wafer is increasing its size so that more power is required to lift up and transport the wafer. In this case, the gas flow rate should be increased and the compressibility effects of gas may be of practical importance.

In the present paper, a computational fluid dynamics method was used to get insight into the Bernoulli levitation. The compressible Navier-Stokes equations furnished with the SST k-ω turbulence model were solved using a fully implicit finite volume scheme. The performance of such non-contact handling device can strongly depend on the operating conditions and device shapes which were investigated in detail. In this study, numerical simulations were carried out on Bernoulli levitation device with various mass flow rate, clearance gap and device shape to obtain the optimal performance of the device. Based on the present results, the flow characteristics around the workpiece were discussed in terms of the total pressure, static pressure and levitation force.