Abstract
Plasmas used as atmospheric pressure ion sources for mass spectrometry are briefly reviewed. The characteristics and analytical capabilities of the microwave-induced plasma (MIP) are discussed. A recently developed microwave-induced plasma ion source configuration is presented, which incorporates a tantalum injector probe (MIP-TIP). The present configuration provides an improvement in sensitivity and stability of the ion signal and in the efficiency of power transfer from the generator to the resonant cavity. Preliminary information obtained, using this improved plasma source, is discussed.