Development of data acquisition system to compute metal electron work function

Abstract

Scanning Kelvin Probe (SKP) microscopy is a technique commonly used to achieve the contact potential difference (CPD) between two surfaces – the sample and the probe. During measurements, a SKP was used to get the voltage and current values of a sample from its work station. In this project, a Graphical User Interface (GUI) was built using MATLAB to calculate and analyze the backing potentials and CPD from the collected values, and eventually to find out the work function across the sample. During the analysis, many factors were also considered when dealing with the values. Certain regression and outlier methods were brought up and applied to achieve a higher accuracy when dealing with raw data.

Once the program is successful in finding the work function of the sample, the GUI will generate a 3D surface plot depending on the type of surface the sample has. Users can continue to observe the changes of the work function between complete scans using different features available in the GUI. Further analysis can be done by sending information back to the SKP work station.