OBSERVATION OF AN INTERSTITIAL MANGANESE IMPURITY IN 6H-SIC

In a 6H-SiC single crystal we observed the electron paramagnetic reson ance (EPR) of a Mn impurity, which is assigned to an interstitial Mn2 (3d5) centre with electron spin S = 5/2. The assignment of Mn2+ to be on an interstitial site is based on the large hyperfine interaction o f 270 MHz. Only the central hyperfine sextet is observed with forbidde n transitions in between. The fine structure lines are broadened beyon d detection by random internal strains; however, the fine structure in teraction causes the forbidden lines. The presence of internal strains is confirmed by the observation of the corresponding EPR Spectra of t he N donors.