This paper discusses the effect of the substrate orientation and crystal growth technique (Czochralski Ct and Float-Zone FZ) on the electrical characteristics of Si n(+) p junction diodes. More in particular, the influence on the static current-voltage and on the low-frequency noise in forward operation is investigated. As is shown, (111) oriented substrates yield diodes with a higher leakage current, a higher ideality factor and a higher noise, compared with (100) junctions. Combining diodes with a different area to perimeter ratio, the origin of the higher noise and leakage current is studied. It is concluded that the increase in noise for (111) substrates is correlated with the higher perimeter leakage current density. The latter is composed of an interface generation and a bulk generation component which are both affected by the orientation and the growth technique of the Si substrate.