ULSI Technology and Materials: Quantitative Answers by Combined Mass Spectrometry Surface Techniques

The progressive microelectronics ULSI device shrinking towards improving the performances has driven the development of new materials and process technologies. A goood example is given by oxynitride, an innovative material which is thought for the next generation of 0.25 mm MOS circuits. Oxynitrides have replaced thermal silicon oxides as gate insulator due to the properties of gook masking against impurity diffusione, together with the excellen dielectric strenght and the better resistance to dielectric breakdown. The strong request from microelectronics industries for a complete and accurate characterization of this new material and the technological processes concerned, has considerably stimulated the research, particularly in the field of analytical methodology. Secondary Ion Mass Spectrometry, linked since the beginning with microelectronics development, shows again to be the most reliable and suitable microanalytical technique to geve answers to this topics. In this work we present some examples of methodologies applied to an accurate quantitative characterization of this new material, together with its impact on the production processes. We show how the complementary employing of several mass spectrometry techniques, such as magnetic sector SIMS, SNMS, SNMS and ToF-SIMS, can give a more complete overview both to process issues and to methodological developments of the techniques themselves