Micro- and nanoscale diamond structuring

The seminar will be devoted to presenting the results of a doctoral thesis which deals with nucleation, growth, and structuring of polycrystalline diamond thin films. In the first part, two alternative methods used to initiate diamond nucleation and growth are investigated and compared to the standardly established nucleation methods. Spontaneous nucleation is studied on horizontally and vertically oriented non-treated (i.e. absence of pre-existing diamond seeds) silicon substrates in a linear plasma CVD system using different deposition parameters. Furthermore, polymer-based nucleation is studied in a focused CVD plasma system. The second part of the thesis deals with the structuring of micro- and nanocrystalline diamond thin films using the technique of microsphere lithography (MSL). This thesis also covers various top-down and bottom-up strategies for manufacturing periodic diamond structures. The preparation of hillock-like structures is demonstrated using a four-step top-down fabrication process (diamond deposition, PS mask preparation, mask modification and diamond etching). Selective area deposition of periodically ordered diamond columns is realised using a bottom-up strategy (PS spheres are employed as a mechanical mask for plasma etching of the seeding layer). Finally, the fabrication of a polycrystalline diamond-based two-dimensional photonic crystal slab (i.e. hexagonal lattice of air holes) is demonstrated.