Abstract: The present invention relates to securing a substrate to an electrostatic chuck to minimise damage to the substrate. In particular, the present invention relates to securing a substrate to an electrostatic chuck provided as part of a substrate scanner in an ion implanter. A method of loading a substrate on an electrostatic chuck of a substrate holder is provided that comprises placing a substrate onto the chuck; supplying a first voltage to an electrode in the chuck thereby causing an electrostatic force due to attraction of the substrate to the chuck; subsequently, but prior to moving the substrate, supplying a second voltage to the electrode greater than the first voltage thereby causing an increased electrostatic force.

Abstract: A particle monitor in the process chamber of a semiconductor device manufacturing apparatus provides a measure of a flux of contaminant particles in the chamber. The flux is measured whilst process conditions are produced in the process chamber and a process parameter is adjusted in response to the measured flux in order to reduce this flux during the process. In an ion implanter, the particle sensor measures the flux of particles entrained with the ion beam at a location in front of the wafer being processed.

Abstract: Dose uniformity of a scanning ion implanter is determined. A base beam current is measured at the beginning and/or the end of a complete scan over the whole substrate area. This base beam current is measured at a time when the measurement should be unaffected by outgassing from a substrate being implanted and a base dose distribution map is then calculated for the scan in question. During the scan itself beam instability events are detected and the magnitude and position in the scan of the detected instability events is measured. Corresponding deviations in the calculated base dose map are determined and subtracted from the previously calculated base dose distribution map to provide a corrected distribution map. By determining overall dose uniformity substractively in this way, good overall accuracy can be obtained with lesser accuracy in the measurement of the beam instability events.

Abstract: An electrically insulating vacuum coupling for use in an ion implanter for connecting any two parts of the vacuum chamber housing together while maintaining the electrical potentials of the two parts. The coupling comprises an inner sleeve of ceramic material (e.g. Al2O3) and an outer sleeve of a polymer/litharge mixture. The polymer may be a urethane polymer. Litharge is included in the material of the outer sleeve to absorb x-rays produced within the vacuum chamber.

Abstract: A performance parameter for an ion implanter is obtained by monitoring vacuum pressure in a vacuum chamber of the implanter to identify pulses of said pressure caused by outgassing from the wafer surfaces during respective scans or groups of scans of the wafer through the ion beam. The pressure values are integrated during the identified pulses to provide a series of pulse pressure integral values which provide the performance parameter. An increase in the integral values indicates deterioration in vacuum system performance.