Patent ID: 6268224
Filing Date: 2001-07-31
Classification: H01L

Abstract:
A method of fabricating a semiconductor wafer, comprising the steps of:implanting ions into said wafer so as to form a polishing endpoint layer in said wafer, said ion-implanted polishing endpoint layer having a first outer level and a second outer level;polishing said wafer in order to remove material from said wafer;detecting a first change in friction when material of said ion-implanted polishing endpoint layer begins to be removed during said polishing step so as to determine that said wafer has been polished to said first outer level of said ion-implanted polishing endpoint layer;detecting a second change in friction when material of said ion-implanted polishing endpoint layer ceases to be removed during said polishing step so as to determine that said wafer has been polished to said second outer level of said ion-implanted polishing endpoint layer; andterminating said polishing step in response to detection of said second change in friction.