Highest Resolution Electrical Measurements
Posted on November 6, 2017 by Amster
The use of Atomic Force Microscopy (AFM) electrical measurement modes is a critical tool for the study of semiconductor devices and process development. A relatively new electrical mode, scanning microwave impedance microscopy (sMIM), measures a material’s change in permittivity and conductivity at the scale of an AFM probe tip. sMIM provides the real and imaginary impedance (Re(Z) and Im(Z)) of the probe-sample interface. By measuring the reflected microwave signal as a sample of interest is imaged with an AFM, we can in parallel capture the variations in permittivity and conductivity and, for doped semiconductors, variations in the depletion-layer geometry. An existing technique for characterizing doped semiconductors, scanning capacitance microscopy, modulates the tip-sample bias and detects the tip-sample capacitance with a lock-in amplifier. A previous study compares sMIM to SCM and highlights the additional capabilities of sMIM, including examples of nano-scale capacitance-voltage curves.
This latest publication of PrimeNano titled Curves for Advanced Characterization of Electrical Properties of Silicon and GaN Structures Using Scanning Microwave Impedance Microscopy (sMIM), can be found in Electronic Device Failure Analysis (EDFA), Volume 19 No. 4, EDFAAO (2017) 4:12-20. You can also download it here.
Copyright 2017. All Rights Reserved