Silicon semiconductor microstructures have demonstrated enhancement in different types of electronic devices, however, controlling the doping within all these devices remain a major challenge. This challenge is increased by the lack of direct methods to quantify the dopant distribution depth in the microstructures. In this paper we present a method that allows the direct measurement of phosphorus doping profile depth in single silicon micropillars. The micropillars were etched on a silicon substrate using Reactive Ion Etching (RIE). In order to perform the dopant distribution measurement, we first thinned the micropillar by milling it using the Focused Ion Beam (FIB) microscope. We then studied the dopant distribution by performing a chemical composition analysis using a Scanning Transmission Microscope (STEM) and Energy Dispersive X-ray Spectroscopy (EDS). The study will outline the fabrication and the analysis methods.