Improving the electrical performance of a conductive atomic force microscope with a logarithmic current-to-voltage converter

A new configuration of conductive atomic force microscope (CAFM) is presented, which is based in a standard CAFM where the typical $I-V$ converter has been replaced by a $logI-V$ amplifier. This substitution extends the current dynamic range from $1–100pAto1pA–1mA$⁠. With the broadening of the current dynamic range, the CAFM can access new applications, such as the reliability evaluation of metal-oxide-semiconductor gate dielectrics. As an example, the setup has been tested by analyzing breakdown spots induced in $SiO2$ layers.