Abstract: Apparatus for determining the speed of sound through a specimen comprises an ultrasound sending transducer, an ultrasound receiving transducer, a pair of laser distance sensors, a display device, a controller in communication with the ultrasound sending transducer, the ultrasound receiving transducer and the pair of laser distance sensors and the display device. The ultrasound sending transducer and one laser distance sensor are supported with a transducer surface in a first plane. The ultrasound receiving transducer and one last distance sensor are supported with a transducer surface in a second plane parallel with the first plane. A support for a specimen is provided between the first and second planes. The controller is programmed for gathering data from the ultrasound transducers and the laser distance sensors for calculating the speed of ultrasound in the specimen and displaying the results.

Abstract: Apparatus for determining the speed of sound through a specimen comprises an ultrasound sending transducer, an ultrasound receiving transducer, a pair of laser distance sensors, a display device, a controller in communication with the ultrasound sending transducer, the ultrasound receiving transducer and the pair of laser distance sensors and the display device. The ultrasound sending transducer and one laser distance sensor are supported with a transducer surface in a first plane. The ultrasound receiving transducer and one last distance sensor are supported with a transducer surface in a second plane parallel with the first plane. A support for a specimen is provided between the first and second planes. The controller is programmed for gathering data from the ultrasound transducers and the laser distance sensors for calculating the speed of ultrasound in the specimen and displaying the results.

Abstract: A method of characterizing the surface of a CMP pad by directing an ultrasound pulse at the surface from an ultrasound transducer that is not in contact with the surface and observing the frequency spectrum of the reflected pulse which is indicative of properties of the surface.

Abstract: An ultrasonic CMP polishing pad analyzer is disclosed. The analyzer provides a manufacturer or other user an ability to inspect a CMP polishing pad without removing the pad from the CMP machine by creating and displaying a topographical image of an in-service polishing pad. The analyzer includes an ultrasonic transducer and an analyzer body mounted to the CMP machine such that the ultrasonic transducer is positioned to receive reflected ultrasonic signals from a surface of the polishing pad.