High speed polishing of silicon dioxide thin films using linear planarization technology

摘要

It has been reported in literature that the polish rate for glass follows the Preston equation, removal rate RR=K_pPV, where K_p is the Preston Coefficient, P is the polish pressure and V is the velocity of the wafer surface relative to the polishing surface. Linear Planarization Technology (LPT) offers the advantage of polishing at very high linear velocities. Polishing experiments using LPT over a wide range of polishing speeds (100 - 1000 fpm) and polishing pressures (3 - 7 psi) were conducted to determine if the silicon dioxide removal rate follows the Preston Equation. Results indicate that the removal rate is non-Prestonian for the process conditions specified. Further investigations revealed that for a given set of parameters, there is transition velocity at which the mechanism of wafer support undergoes a fundamental change.