Endpoint detection apparatus, planarizing machines with endpointing apparatus, and endpointing methods for mechanical or chemical-mechanical planarization of microelectronic substrate assemblies

A machine for planarizing a microelectronic substrate assembly, comprising:

• a polishing pad having a planarizing surface defining a planarizing plane and a backside opposite the planarizing surface;
• a carrier assembly having a head configured to hold a substrate assembly against the planarizing surface;
• a table including a base and a primary plate moveable with respect to the base in a lateral motion corresponding to the lateral drag forces, the base having a base surface supporting the polishing pad and at least a first stop surface extending from the base surface transverse to the planarizing plane, and the primary plate having a bearing surface facing the backside of the polishing pad to support at least a portion of the polishing pad in a planarizing zone and at least a first contact surface adjacent to the first stop surface;
• a drive system coupled one of the table and the carrier assembly to move the substrate assembly relative to the polishing pad in a lateral direction at least generally parallel to the planarizing plane to generate lateral drag forces when the substrate assembly engages the planarizing surface;
• and
• at least a first force detector contacting the first stop surface and the first contact surface at a first load site to sense lateral forces between the base and the primary plate.