Method of fabricating a porous polymeric material by electrophoretic deposition

A method of making a porous polishing pad material for a polishing pad, the method comprising electrophoretic deposition by immersing spaced apart electrodes in a bath, and while mixing the bath, impressing the electrodes with controlled electrical conditions, the method further comprising the steps of:

• immersing spaced apart electrodes in a bath having polymeric particles and water;
• impressing the electrodes with the controlled electrical conditions that consist of, a controlled voltage difference across the electrodes, and 4 controlled current flow through the electrodes;
• depositing the polymeric particles on one of the electrodes to form a polymeric mass while generating gaseous bubbles within the polymeric mass, which bubbles open at an exterior surface of the polymeric mass to provide a porous polishing pad material having pores therein that open at an exterior polishing surface on the polishing pad material;
• and
• varying one of the controlled electrical conditions over a time duration as a thickness of the polymeric mass increases to increase the lengths of the bubbles transverse to the thickness of the polymeric mass.