A study on the conduction path in undoped polycrystalline diamond films

Electrochemical Impedance Spectroscopy Studies of HF CVD Diamond Films

“…Above is in accordance with earlier studies, which have also show that the grain boundaries within the lms were the main conduction path in undoped polycrystalline diamond lms [6,7].…”

“…The electrical properties of undoped polycrystalline diamond (PCD) have been studied by many researchers [6,7] and dierent mechanisms of conduction have been proposed. According to Sugino et al [8] the conduction in diamond lms can be described by three independent mechanisms: frequency-independent * corresponding author; e-mail:…”

Electrical Conduction in Polycrystalline CVD Diamond: Temperature Dependent Impedance Measurements

“…This is because a number of defects, non-diamond phases at grain boundaries are present, which may influence the conduction path and the mobility of the charge carriers [14,15]. Most recently, Lee et al has reported the similar results using Cu and Ag electroplating technique that the electrical conduction path in polycrystalline diamond films is the grain boundaries within the films [16]. By using impedance spectroscopy, we have the similar conclusion that the single semicircular response from this type of black diamond originates from grain boundaries.…”

The nature of ion-implanted contacts to polycrystalline diamond films

“…The reason for the peculiar behavior found here must be related to the polycrystalline nature of the samples. Previous studies by several groups have shown that leakage currents in polycrystalline diamond films are mainly through the grain-boundaries [7]. Therefore, any insight into the mechanism which leads to the leakage increase following ion implantation should naturally be directed at finding reasons for enhanced conductivity between the implanted contact and the grain-boundaries or the implantation effect on the grain boundaries.…”

“…The role that the granular nature of polycrystalline CVD diamond and the role that the grain boundaries play in the leakage through the layer was not searched for, and hence was not noticed in that work. More recent work [7] has shown that there exist conduction pathways through thick layers of undoped polycrystalline diamond layers, which are attributed to percolative current flow in channels along the grain boundaries. In these measurements material which was not particularly resistive was used, and evaporated Ti/Au contacts were applied to thick slabs of free-standing diamond films.…”