Methods and apparatus for detecting errors in real time in CMP processing. A method includes disposing a semiconductor wafer onto a wafer carrier in a tool for chemical mechanical polishing (“CMP”); positioning the wafer carrier so that a surface of the semiconductor wafer contacts a polishing pad mounted on a rotating platen; dispensing an abrasive slurry onto the rotating polishing pad while maintaining the surface of the semiconductor wafer in contact with the polishing pad to perform a CMP process on the semiconductor wafer; in real time, receiving signals from the CMP tool into a signal analyzer, the signals corresponding to vibration, acoustics, temperature, or pressure; and comparing the received signals from the CMP tool to expected received signals for normal processing by the CMP tool; outputting a result of the comparing. A CMP tool apparatus is disclosed.