Chemical planarization

A method of chemically planarizing a substrate, the method comprising;

• introducing an abrasive-free planarization solution onto a porous pad, the abrasive-free planarization solution comprising a hydrolyzing agent and a complexing agent;
• contacting the substrate with the porous pad while moving the porous pad such that higher portions of the substrate contact the porous pad and lower portions of the substrate do not contact the porous pad;
• removing material from the higher portions of the substrate via hydrolyzing agent on the porous pad to reduce a height of the higher portions of the substrate relative to the lower portions of the substrate;
• and
• complexing, via the complexing agent, the material removed.

A chemical planarization system, comprising:

• a porous pad comprising
• a first polymer layer configured to contact a substrate during abrasive-free chemical planarization, the first polymer layer comprising a first, larger average pore size, and
• a second polymer layer positioned on an opposite side of the first polymer layer as a substrate-contacting side of the first polymer layer, the second polymer layer comprising a second, smaller average pore size;
• a planarization solution introduction system for introducing an abrasive-free planarization solution onto the porous pad, the abrasive-free planarization solution comprising a functionalizing compound comprising one or more of a complexing agent or a hydrolyzing agent;
• a platen supporting the porous pad;
• and
• a substrate holder configured to hold a substrate against the first surface of the porous pad, wherein one or more of the platen and the substrate holder are configured to rotate to impart rotational motion of the substrate relative to the porous pad during abrasive-free chemical planarization.