The effects of bias voltage, bias time, frequency and duty cycle on the nucleation were investigated. Pulsed duty cycles were varied from 0.4 - 1.4 µs and the frequency varied between 50 – 250 KHz. The substrates were pre-treated by a DC bias using 3 vol. % methane in argon / hydrogen plasma. Growth and surface roughness were controlled using pulsed frequencies, with mean Ra values of 20 nm. Films were characterised in terms of orientation and surface roughness using transmission electron microscopy (TEM) and atomic force microscopy (AFM). Bias enhanced nucleation is shown to profoundly increase the nucleation densities by promoting ion-bombardment of the substrate surface thus creating nucleation sites for subsequent growth on substrates such as titanium alloys and steel. This technology promotes smooth diamond facets without abrasive surface damage. Controlling the surface roughness and morphology is of critical importance for many new biomedical and electronic devices.