US Patent 7163437 System with sealed polishing pad

A polishing pad, polishing system, method of making a polishing pad and method of using a polishing pad. The polishing pad includes a polishing layer having a polishing surface, a backing layer with an aperture and a first portion that is permeable to liquid, and a sealant that penetrates a second portion of the backing layer adjacent to and surrounding the aperture such that the second portion is substantially impermeable to liquid. The aperture is positioned below a substantially fluid-impermeable element.