Controlled nano-patterning using focused electron beam induced deposition

Focused electron beam induced processing (FEBIP) comprising FEBID (deposition) and FEBIE (etching) is a direct write or etch, single step technique for high resolution nano-patterning. The whole process takes place inside a single tool, the scanning electron microscope (SEM). A focused electron beam hits the sample in the presence of a precursor gas which contains the element to be deposited. The precursor molecules adsorb to the surface of the substrate. The adsorbed precursor molecules are dissociated with a certain probability (given by the dissociation cross section) by the primary, secondary and back scattered electrons into a deposited fragment and volatile byproducts. FEBID provides great potential for 3D nano-printing due to its flexibility and the absence of resists and subsequent processing steps.
The work described in this thesis was part of a Marie Skłodowska-Curie Training Network on ‘Low energy ELEctron driven chemistry for the advantage of emerging NAno-fabrication methods’ (ELENA). In particular, three challenges to the FEBID process were addressed to achieve control over the process for nanofabrication, i) the purity of the deposits, ii) the speed of the process and iii) control over the 3D-shape of deposits....