The images were created by writing defined patterns with a focussed ion beam source ('FIB') into a silicon surface. The written images were observed with the electron microscope UHV-Gemini Column. Both instruments are mounted to the same UHV-chamber using the same rotatable sample stage.
The sample is pure Si with some contaminations of Oxide and Carbon. When writing the structures the sample was rotated with the normal of the sample surface showing in direction of the FIB-source.
The images were created by milling a bitmap of the size 512 x 512 pixel. Each gray value of the image was interpreted as the milling time at the given x/y position. Black means no time to stop at this pixel, white means maximum time of milling and every gray value in between the propotional time between zero and maximum sputtering time.
The degradation of material at each pixel is depending on the time being exposed to the ion beam with the element specific sputter rate.
The size of the image was chosen to 15μm x 15μm, so that each pixel of the written image corresponds to a real size of approx. 30nm. |
