This Small Business Innovation Research Phase I project will develop an improved micro x-ray fluorescence instrument for thin film measurements. A new technique, monochromatic micro x-ray fluorescence (MMXRF) analysis using doubly curved crystal optics, can meet this significant market need. A toroidal crystal can focus characteristic x-rays from a microfocus x-ray source based upon diffraction. The focused beam is monochromatic and the beam size is expected to be significantly smaller than that of current MXRF systems. In this Phase I project, toroidal crystals for focusing Cu Ka1 and Mo Ka1 photons will be designed and fabricated using silicon and mica crystals. The reflection and focusing properties of the optics will be investigated and the feasibility of the MMXRF technique for critical semiconductor applications will be evaluated.<br/> This technique will provide high sensitivity and enhance excitation of low Z elements with the selection of beam energy. In addition, this technique will significantly increase the speed of high energy x-ray measurements. An MMXRF instrument is expected to provide process control in the metallization process of silicon wafers and chip packaging.