Electron-irradiation-induced deep levels in n-type 6H–SiC

Abstract

Articles you may be interested in Comparison of crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te nanocrystalline thin films: Effects of homogeneous irradiation with an electron beam Electron-irradiation-induced divacancy in lightly doped silicon The recovery of the electrical resistivity and thermoelectric power in a number of n-and p-type a-tin samples, irradiated at low temperature, is considered. Three distinct first-order stages in the temperature range 20-50 K are observed. A fractional defect recovery has been deduced such that relative percentages of lA : 18 : Ie =90 : 4 : 6 anneal in the three stages. Activation energy scaling factors were found to be 69, 94, and 122 meV, respectively, for the three stages. Carrier mobilities as functions of carrier and defect concentration were calculated and found to be in good agreement with previously published values. Estimates for these quantities were also deduced when the samples were near to their intrinsic states (n. ~ nh)' A c1ose-pair-defect charge carrier trapping model provides a consistent explanation for all damage and recovery data.

Low Energy Electron Irradiation Induced Deep Level Defects in6H−SiC: The Implication for the Microstructure of the Deep LevelsE1/E2Chen1, Yang2, Gong3 et al. 2004Phys. Rev. Lett.Self Cite231180View full textAdd to dashboardCite

“…It is plausibly to associate this shoulder with another peak having ionization energy and capture cross section very close to those of the E 1 =E 2 . This observation of a peak located on the low temperature of E 1 =E 2 was also observed by Gong et al [5] who labeled it ED2. The composite (E 1 =E 2 ED2) peak data was fitted by superposition of Gaussians.…”

“…Figure 1 shows typical DLTS spectra of the electron irradiated samples (dosage of 5 10 15 cm ÿ2 ) with E e 0:2 MeV to 1.7 MeV. It is seen that peaks at 120, 200, and 260 K (previously reported as ED1 [5], E 1 =E 2 [2 -9], and E i [4,6,9]) are clearly seen only for the samples irradiated with electrons having energies E e 0:3 MeV. No signal is found in the as-grown and the 0.2 MeV irradiated samples (with DLTS measurement detect limiting 10 12 cm ÿ3 ).…”

“…Suggestions have ranged from the V C V Si divacancy [5], the negatively charged V C [6], the V Si complex [8], the V C C Si defect [9], or the N i -C i [10]. As discussed, the observed 0.3 MeV threshold for the E 1 =E 2 gives strong evidence that these defects originate from the displacement of the C atom in the SiC sublattice.…”

“…The E 1 =E 2 doublet is not only the most dominant but also appears to be the most thermal stable in electron irradiated n-type 6H-SiC. The microstructure responsible for this level has been attributed to V C V Si [5], V Si complex [8], V C related defect [6,9], and N i -C i complex [10].…”

Vacancy Defects Detected by Positron Annihilation

“…12 [54]- [71]. Early studies show that the energy levels at E C -0.3∼0.4 eV labeled E 1/2 (same as ED 3H /ED 4 and L 3/4 ) [55,57] and at E C -0.6∼0.7 eV labeled Z 1/2 (same as ED 7 and L 7/8 ) [55,57] are the major products in 6H-SiC due to bombardment [60,61,72]. The corresponding energy levels in 4H-SiC are labeled Z 1/2 at E C -0.6∼0.7 eV (same as EH 2 ) [68] and RD 1/2 at E C -0.9∼1.0 eV (same as EH 4 ) [68] in 4H-SiC.…”