Hyperfine Interaction of Nitrogen Donor in 4H-SiC Studied by Pulsed-ENDOR
Shallow N donors in n-type 4H-SiC were studied by electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR). For the N donor at the cubic site (Nk) in 4H-SiC, the hyperfine (hf) constants of the interaction with the nearest neighbour (NN) 29Si atom along the c axis were determined as A = 41.07 MHz and A^ = 41.31 MHz. For other three NN Si atoms in the basal plane, the hf tensor has C1h symmetry and the principal values Axx = 5.94 MHz, Ayy = 5.06 MHz and Azz = 14.25 MHz. Our EPR and ENDOR observations unambiguously confirm that the N donor occupies the C site in 4H-SiC lattice and also reveal a considerable amount of the spin density of Nk (~23.9%) which was not obtained in previous studies.
Roberta Nipoti, Antonella Poggi and Andrea Scorzoni
N. T. Son et al., "Hyperfine Interaction of Nitrogen Donor in 4H-SiC Studied by Pulsed-ENDOR", Materials Science Forum, Vols. 483-485, pp. 351-354, 2005