High-quality single-crystal diamond films were homoepitaxially grown by chemical vapor deposition onto low cost high-pressure high-temperature diamond substrates. The transport properties of the obtained samples were studied by photoresponse characterization. Fast ultraviolet (5 ns) laser pulses at 215 nm were used as a probe. The time evolution of the photoinduced current was observed to closely reproduce the laser pulse shape, thus indicating a time response lower than the adopted laser pulse duration. Very stable and reproducible response was measured, so that neither priming nor memory effects are observed. However, a minor slow component shows up in the charge-integrated sample response, whose temperature dependence was investigated in a -25-+50 degrees C range. A systematic speed up of this slow component of the sample signal is observed, indicating the presence of shallow centers producing trapping-detrapping effects. The experimental results are discussed in the framework of a trapping-detrapping model affecting the charge transport mechanism and an activation energy of E-a=0.4 eV was derived for the shallow trapping centers.
Balducci, A., Marinelli, M., Milani, E., Morgada, M., Prestopino, G., Scoccia, M., et al. (2005). Trapping-detrapping defects in single crystal diamond films grown by chemical vapor deposition. APPLIED PHYSICS LETTERS, 87(22), 222101 [10.1063/1.2135384].
Trapping-detrapping defects in single crystal diamond films grown by chemical vapor deposition
MARINELLI, MARCO;MILANI, ENRICO;TUCCIARONE, ALDO;VERONA RINATI, GIANLUCA
2005-01-01
Abstract
High-quality single-crystal diamond films were homoepitaxially grown by chemical vapor deposition onto low cost high-pressure high-temperature diamond substrates. The transport properties of the obtained samples were studied by photoresponse characterization. Fast ultraviolet (5 ns) laser pulses at 215 nm were used as a probe. The time evolution of the photoinduced current was observed to closely reproduce the laser pulse shape, thus indicating a time response lower than the adopted laser pulse duration. Very stable and reproducible response was measured, so that neither priming nor memory effects are observed. However, a minor slow component shows up in the charge-integrated sample response, whose temperature dependence was investigated in a -25-+50 degrees C range. A systematic speed up of this slow component of the sample signal is observed, indicating the presence of shallow centers producing trapping-detrapping effects. The experimental results are discussed in the framework of a trapping-detrapping model affecting the charge transport mechanism and an activation energy of E-a=0.4 eV was derived for the shallow trapping centers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.