The never-ending scaling and increase in complexity of integrated circuits requires continual development of tools to understand and control the process of fabrication. However, scaling alone has not been enough to achieve improvements in performance. Material properties, dopant levels and other non-dimensional properties are now critical in increasing device performance beyond dimensional scaling. In the study presented here we report on advancements made in the measurement of electrical properties of materials using scanning Microwave Impedance Microscopy (sMIM). These advancements address the needs for certain electrical property measurements in semiconductors and have room for future growth. The latest incarnation of sMIM, the ScanWave Pro, achieves a sensitivity of less than 0.1 aF in capacitance and can measure minute changes in dielectric constant (k-value) and dopant levels in films. Additionally, we studied the response of these measurements across a range of materials and dopants used in semiconductor manufacturing and report here the results. For dielectric films and dopant levels, the response of the sMIM signal is log-linear in each case thus enabling easy and reliable quantification of measurements. The repeatability of the measurements was also studied and was found to be well within the requirements for process monitoring. This in turn, has enabled reliable quantification of results for this wide range of material properties. Up until now, sMIM measurements were qualitative and that limited their value. We implemented quantification of sMIM results and report on the approach and real-device results. Lastly, we explore additional potential applications and future developments.

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