Chemo-mechanical magneto-rheological finishing (CMMRF) of silicon for microelectronics applications

A new finishing process, namely, chemo-mechanical magneto-rheological finishing (CMMRF) was developed for polishing silicon blanks that combines the beneficial features of chemical mechanical polishing (CMP) and magneto-rheological finishing (MRF) without the detrimental effects of either process involved. Chemical reactions associated with CMP are used to enhance the finish quality while the magneto-rheological polishing fluid is used to control the magnitude of the forces acting on the workpiece that controls the material removal rates (MRR) and minimizes the surface integrity problems. An apparatus for CMMRF was designed and built for nanometric finishing of silicon substrates. This process is able to finish silicon blanks with nanometric finish, minimal surface defects, and higher removal rates. (C) 2010 CIRP.