| 1. |
- Khirunenko, L, et al.
(författare)
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Interstitial carbon related defects in low-temperature irradiated Si: FTIR and DLTS studies
- 2005
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Ingår i: Solid State Phenomena. - 1012-0394. ; 108-109, s. 261-266
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Tidskriftsartikel (refereegranskat)abstract
- The evolution of radiation-induced carbon-related defects in low temperature irradiated oxygen containing silicon has been studied by means of Fourier transform infrared absorption spectroscopy (FTIR) and deep level transient spectroscopy (DLTS). FTIR measurements have shown that annealing of interstitial carbon atom C-i, occurring in the temperature interval 260-300 K, results in a gradual appearance of a number of new absorption bands along with the well known bands related to the CiOi complex. The new bands are positioned at 812, 910.2, 942.6, 967.4 and 1086 cm(-1). It has been found that the pair of bands at 910 and 942 cm(-1) as well as another set of the bands at 812, 967.4 and 1086 cm(-1) display identical behavior upon isochronal annealing, i.e. the bands in both groups appear and disappear simultaneously. The disappearance of the first group occurs at T = 285-300 K while the second group anneals out at T = 310-340 K. These processes are accompanied by an increase in intensity of the bands related to CiOi. It is suggested that intermediate states (precursors) are formed upon the transformation from a single (isolated) Ci atom to a stable CiOi defect. The results obtained in DLTS studies are in agreement with the FTIR data and show unambiguously the formation of CiOi precursors with slightly lower activation energy for the hole emission as compare to that for the main CiOi state.
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| 2. |
- Markevich, VP, et al.
(författare)
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Electrically active radiation-induced defects in Czochralski-grown Si with low carbon content
- 2005
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Ingår i: Journal of Physics: Condensed Matter. - : IOP Publishing. - 1361-648X .- 0953-8984. ; 17:22, s. 2331-2340
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Tidskriftsartikel (refereegranskat)abstract
- Electrically active defects induced by electron irradiation in Czochralski (Cz)grown Si crystals with low carbon content (N-C <= 2 x 10(15) cm(-3)) have been studied by means of Hall effect measurements, deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS (LDLTS). It has been found that in n-type carbon-lean Cz-Si irradiated at room temperature a centre with an acceptor level at E-c - 0.11 eV (E-0.11) is one of the dominant radiation-induced defects. This centre is not observed after irradiation in Cz-Si crystals with NC > 10(16) cm(-3). The E-0.11 trap anneals out in the temperature range 100-130 degrees C with the activation energy 1.35 eV. In p-type Cz-Si crystals with low carbon content and boron (NB 2 x 10(14) cm(-3)) one of the dominant radiation-induced defects has been found to be a bistable centre with an energy level at E-v +0.255 eV (H-0.255). It has been inferred from the analysis of temperature dependences of electron occupancy of this level that it is the E(0/++) level of a defect with negative Hubbard correlation energy (negative U). The activation energy for hole emission from the doubly positively charged state of the H0.255 Centre has been determined as 0.358 eV from LDLTS measurements. It is argued that the E-0.11 and H-0.255 energy levels are related to a complex incorporating an oxygen dimer and Si self-interstitial.
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| 3. |
- Markevich, VP, et al.
(författare)
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Electronic properties and structure of a complex incorporating a self-interstitial and two oxygen atoms in silicon
- 2005
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Ingår i: Solid State Phenomena. - 1012-0394 .- 1662-9779. ; 108-109, s. 273-278
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Tidskriftsartikel (refereegranskat)abstract
- The electronic properties and structure of a complex incorporating a self-interstitial (i) and two oxygen atoms are presented by a combination of deep level transient spectroscopy (DLTS), infrared absorption spectroscopy and ab-initio modeling studies. It is argued that the IO2 complex in Si can exist in four charge states (IO2-, IO20, IO2+, and IO2++). The first and the second donor levels of the IO2 complex show an inverted location order in the gap, leading to a E(0/+ +) occupancy level at E-V + 0.255 eV. Activation energies for hole emission, transformation barriers between different structures, and positions of LVM lines for different configurations and charge states have been determined. These observables were calculated by density-functional calculations, which show that they are accounted for if we consider at least two charge-dependent defect structures.
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| 4. |
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