TY - JOUR
T1 - A Drude model analysis of conductivity and free carriers in boron-doped diamond films and investigations of their internal stress and strain
AU - Manciu, Felicia S.
AU - Manciu, Marian
AU - Durrer, William G.
AU - Salazar, Jessica G.
AU - Lee, Kendall H.
AU - Bennet, Kevin E.
N1 - Funding Information:
Acknowledgements This work was supported by The Grainger Foundation, the NIH R01 NS075013 award, and by a research agreement between the University of Texas at El Paso and the Mayo Clinic.
PY - 2014/8
Y1 - 2014/8
N2 - Boron-doped diamond (BDD) has seen a substantial increase in interest for use as electrode coating material for electrochemistry and studies of deep brain stimulation mechanism. In this study, we present an alternative method for determining important characteristics, including conductivity, carrier concentration, and time constant, of such material by the signature of Drude-like metallic behavior in the far-infrared (IR) spectral range. Unlike the direct determination of conductivity from the four-point probe method, using far-IR transmittance provides additional information, such as whether the incorporation of boron results in a large concentration of carriers or in inducing defects in the diamond lattice. The slightly doped to medium-doped BDD samples that were produced using chemical vapor deposition and analyzed in this work show conductivities ranging between 5.5 and 11 (Ω cm)-1. Different growth conditions demonstrate that increasing boron concentration results in an increase in the carrier concentration, with values between 7.2 × 1016 and 2.5 × 1017 carriers/cm3. Addition of boron, besides leading to a decrease in the resistivity, also resulted in a decrease in the time constant, limiting BDD conductivity. Investigations, by confocal Raman mapping, of the induced stress in the material due to interaction with the substrate or to the amount of doping are also presented and discussed. The induced tensile stress, which was distributed closer to the film-substrate interface decreased slightly with doping.
AB - Boron-doped diamond (BDD) has seen a substantial increase in interest for use as electrode coating material for electrochemistry and studies of deep brain stimulation mechanism. In this study, we present an alternative method for determining important characteristics, including conductivity, carrier concentration, and time constant, of such material by the signature of Drude-like metallic behavior in the far-infrared (IR) spectral range. Unlike the direct determination of conductivity from the four-point probe method, using far-IR transmittance provides additional information, such as whether the incorporation of boron results in a large concentration of carriers or in inducing defects in the diamond lattice. The slightly doped to medium-doped BDD samples that were produced using chemical vapor deposition and analyzed in this work show conductivities ranging between 5.5 and 11 (Ω cm)-1. Different growth conditions demonstrate that increasing boron concentration results in an increase in the carrier concentration, with values between 7.2 × 1016 and 2.5 × 1017 carriers/cm3. Addition of boron, besides leading to a decrease in the resistivity, also resulted in a decrease in the time constant, limiting BDD conductivity. Investigations, by confocal Raman mapping, of the induced stress in the material due to interaction with the substrate or to the amount of doping are also presented and discussed. The induced tensile stress, which was distributed closer to the film-substrate interface decreased slightly with doping.
UR - http://www.scopus.com/inward/record.url?scp=84903517786&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84903517786&partnerID=8YFLogxK
U2 - 10.1007/s10853-014-8309-x
DO - 10.1007/s10853-014-8309-x
M3 - Article
AN - SCOPUS:84903517786
SN - 0022-2461
VL - 49
SP - 5782
EP - 5789
JO - Journal of Materials Science
JF - Journal of Materials Science
IS - 16
ER -