Title :
A new theory for CMP with soft pads
Author :
Shi, Frank G. ; Zhao, Bin ; Wang, Shi-Qing
Author_Institution :
California Univ., Irvine, CA, USA
Abstract :
A new theory for chemical-mechanical polishing with soft pads is developed. In contrast to the conventional Preston´s equation, the pressure dependence of the removal rate for CMP with soft pads is found to be nonlinear, i.e. RR∝P2/3. The combined effect of both pressure and the elastic modulus of the wafer (Hw) and the pad (Ha) on the CMP removal rate can be characterized by a dimensionless parameter, Ea1/3P2/3/E w. The new results are shown to be consistent with available experimental evidence on dielectric films. This theory thus may provide an important basis for understanding CMP mechanisms, as well as for optimization of experimental parameters for actual process design
Keywords :
chemical mechanical polishing; design engineering; dielectric thin films; elastic moduli; integrated circuit interconnections; integrated circuit metallisation; optimisation; semiconductor process modelling; CMP; CMP mechanisms; CMP removal rate; Preston´s equation; chemical-mechanical polishing; dielectric films; experimental parameter optimization; nonlinear CMP removal rate pressure dependence; pad elastic modulus; process design; soft CMP pads; wafer elastic modulus; Abrasives; Atom optics; Chemical engineering; Design optimization; Dielectric films; Manufacturing; Microelectronics; Nonlinear equations; Planarization; Semiconductor materials;
Conference_Titel :
Interconnect Technology Conference, 1998. Proceedings of the IEEE 1998 International
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-4285-2
DOI :
10.1109/IITC.1998.704755
