Local impedance imaging of boron-doped polycrystalline diamond thin films
PBN-AR
Instytucja
Wydział Chemiczny (Politechnika Gdańska)
Informacje podstawowe
Główny język publikacji
ENG
Czasopismo
APPLIED PHYSICS LETTERS
ISSN
0003-6951
EISSN
Wydawca
DOI
URL
Rok publikacji
2014
Numer zeszytu
Strony od-do
1-5
Numer tomu
105
Identyfikator DOI
Liczba arkuszy
Słowa kluczowe
BORON-DOPED DIAMOND
IMPEDANCE SPECTROSCOPY
LOCAL IMPEDANCE IMAGING
SCANNING PROBE MICROSCOPY
Streszczenia
Język
Treść
Local impedance imaging (LII) was used to visualise surficial deviations of AC impedances in polycrystalline boron-doped diamond (BDD). The BDD thin film electrodes were deposited onto the highly doped silicon substrates via microwave plasma-enhanced CVD. The studied boron dopant concentrations, controlled by the [B]/[C] ratio in plasma, ranged from 1 × 1016 to 2 × 1021 atoms cm−3. The BDD films displayed microcrystalline structure, while the average size of crystallites decreased from 1 to 0.7 μm with increasing [B]/[C] ratios. The application of LII enabled a direct and high-resolution investigation of local distribution of impedance characteristics within the individual grains of BDD. Such an approach resulted in greater understanding of the microstructural control of properties at the grain level. We propose that the obtained surficial variation of impedance is correlated to the areas of high conductance which have been observed at the grain boundaries by using LII. We also postulate that the origin of high conductivity is due to either preferential boron accumulation, the presence of defects, or sp2 regions in the intragrain regions. The impedance modulus recorded by LII was in full agreement with the bulk impedance measurements. Both variables showed a decreasing trend with increasing [B]/[C] ratios, which is consistent with higher boron incorporation into BDD film.
Inne
System-identifier
129064