Method and apparatus for wireless transfer of chemical-mechanical planarization measurements

A method for transmitting data from a planarizing apparatus having a first portion and a second portion movable relative to the first portion to planarize a semiconductor substrate positioned between the first and second portions, the method comprising:

• supporting a transmitter on the second portion of the planarizing apparatus;
• coupling more than one transmitting transducer to the transmitter, the transmitting transducers being positioned on the second portion and spaced apart from the transmitter;
• measuring a value of a selected property of one of the planarizing apparatus and the semiconductor substrate and generating a sensor signal corresponding to the value of the selected property;
• storing the sensor signal in a memory device of the planarizing apparatus;
• transmitting the sensor signal from the memory device through the transmitting transducers.

A method for detecting removal of material from a substrate, the substrate having a first surface and a second surface opposite the first surface, the substrate being light transmissive from the first surface to a point proximate to the second surface, the second surface having a reflective layer attached thereto, the method comprising:

• removing at least a portion of the reflective layer;
• directing light through the first surface of the substrate and toward the reflective layer with a light source;
• detecting light reflected by the reflective layer through the first surface of the substrate;
• generating a signal corresponding to the detected light;
• and
• communicating the signal to a transmitter that is coupled to a plurality of transmitting transducers to wirelessly communicate the signal to a receiver.