Microwave Microscope for Nano-Imaging of Semiconductor Devices and Biological Cells

A new volumetric scanning microwave microscope (VSMM) is presented that operates at 1-20 GHz frequencies allowing for nanoscale imaging with <10 nm resolution. SMM is a recent development in nanoscale imaging technique that combines the lateral resolution of atomic force microscopy (AFM) with the high measurement precision of microwave analysis at GHz frequencies. It consists of an AFM interfaced with a vector network analyzer (VNA). SMM allows measuring complex materials properties for nanoelectronics, materials science, and life science applications. Supported by an EC funded collaborative research project (VSMMART-Nano) a demonstrator setup was developed for calibrated impedance and permittivity measurements of semiconductor devices and functional materials, as well as bio-imaging of living cells in liquid. High frequency calibration procedures and subsurface measurement workflows are presented. In particular, calibrated capacitance and resistance measurements are shown with a noise level of 1 aF [1, 2]. Calibrated dopant profiles are measured from 10E14 to 10E20 atoms/cm3 for nanoelectronics characterization [3, 4]. Experimental investigations are complemented by finite element modeling (FEM) using the 3D architecture of the AFM probe and the sample [5, 6]. Finally, first GHz measurements of bacteria and cells in liquid buffer solution are presented with nanoscale resolution.

Funding acknowledgment: The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007- 2013) under grant agreement n° 280516.

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