Title: Computational model for the steady-state elasto-hydrodynamic interaction in wafer slicing process using wiresaw
Authors: Liqun Zhu, Imin Kao
Addresses: Manufacturing and Automation Laboratory, Department of Mechanical Engineering, State University of New York, Stony Brook, NY 11794-2300, USA. ' Manufacturing and Automation Laboratory, Department of Mechanical Engineering, State University of New York, Stony Brook, NY 11794-2300, USA
Abstract: A computational model for analysing the steady state elasto hydrodynamic (EHD) interaction in the wiresaw slicing process is presented in this paper. In this model, the coupling of the steady state motion of the translating wire and the hydrodynamic behaviour of the abrasive carrying slurry is studied. A numerical scheme incorporating the finite element method (FEM) and Inexact Newton-GMRES method is employed to solve the governing equations. By applying this method, better computational efficiency can be achieved than by using the typical Newton-Raphson method. Therefore, extensive parametric studies are made possible. Results from the parametric studies indicate that the noncontact floating machining mechanism dominates the wafer slicing process using the wiresaw. Direct contact machining, however, also may occur when the contact span between the wire and the ingot is short, coupled with the lack of slurry. Simulation results also show that too large a bow angle of the wire may cause the breakdown of proper EHD condition, resulting in the ductile ploughing of abrasive particles on the ingot surface. This computational model can provide insights into the mechanism of the wiresaw slicing process, and suggest process control methods to facilitate industrial wafer slicing process using slurry wiresaws.
Keywords: wiresaw slicing; wafer slicing; semiconductor manufacturing; elasto-hydrodynamic interaction; finite element method; FEM; inexact Newton-GMRES method; parametric studies; translating wire; hydrodynamic behaviour; abrasive-carrying slurry; noncontact floating machining mechanism; simulation; ductile ploughing; process control; slurry wiresaws; wiresaw machining; wafer fabrication.
International Journal of Manufacturing Technology and Management, 2005 Vol.7 No.5/6, pp.407 - 429
Published online: 02 Sep 2005 *Full-text access for editors Access for subscribers Purchase this article Comment on this article