Deep level defects in electron-irradiated 4H SiC epitaxial layers

Abstract

Annealing behavior between room temperature and 2000°C of deep level defects in electron-irradiated n -type 4H silicon carbide J. Appl. Phys. 98, 043518 (2005); 10.1063/1.2009816 Deep levels created by low energy electron irradiation in 4 H -SiC A deep level transient spectroscopy study of electron irradiation induced deep levels in p-type 6H-SiCDeep level defects in electron-irradiated 4H SiC epitaxial layers grown by chemical vapor deposition were studied using deep level transient spectroscopy. The measurements performed on electron-irradiated p ϩ n junctions in the temperature range 100-750 K revealed several electron traps and one hole trap with thermal ionization energies ranging from 0.35 to 1.65 eV. Most of these defects were already observed at a dose of irradiation as low as Ϸ 5ϫ10 13 cm Ϫ2 . Dose dependence and annealing behavior of the defects were investigated. For two of these electron traps, the electron capture cross section was measured. From the temperature dependence studies, the capture cross section of these two defects are shown to be temperature independent.

Deep levels in iron doped n- and p-type 4H-SiC

“…20) and EH6/7 (Ref. 21) were observed. The defect concentrations of the intrinsic levels are in the low 10 13 cm À3 range for the reference and slightly higher for the Fe-doped sample, which may indicate that we induce more intrinsic defects by disturbing the SiC lattice with the doping.…”

Deep levels in tungsten doped n-type 3C–SiC

“…The electronic properties for these levels are summarized in Table I. For the shallower tungsten peak, labeled W1, the capture cross section was determined using different filling pulse lengths 21 The meas of the W2 and EH6/7 did not change in a temperature window of 30 K, whereas the capture cross section of the Z 1/2 -level showed a clear temperature dependence. 22 The DLTS spectrum of 6H-SiC intentionally doped with W is also shown in Fig.…”

Quantitative comparison between Z1∕2 center and carbon vacancy in 4H-SiC

“…Deep levels in electron-irradiated samples Figure 1 shows DLTS spectra observed in a D sample (N d : 1:6 Â 10 17 cm À3 ) irradiated with an electron fluence of 3:1 Â 10 18 cm À2 . In this sample, the ET1 (E C À 0:30 eV), 8 EH 1 (E C À 0:34 eV), 18 Z 1=2 (E C À 0:67 eV), 1 EH 5 (E C À 1:3 eV), 18 ET4 (E C À 1:3 eV), and EH 6=7 (E C À 1:5 eV) 18 centers were observed. The activation energy was derived by assuming a temperature-independent capture cross section.…”