Hydrogen–rhodium complexes in silicon

New hydrogen-induced deep levels in rhodium-doped n- and p-type silicon were observed after hydrogenation by wet-chemical etching. The levels were studied by DLTS measurements on Schottky diodes. We have found in n-type samples the levels E(150) at EC −0.33 eV; E(90) at EC −0.16 eV; and E(70) at EC −0.14 eV. Levels E(150) and E(270) belong to the substitutional rhodium donor and acceptor. Evidence is presented that the level E(70), which was formerly ascribed to isolated rhodium, is due to a hydrogen–rhodium complex. In p-type samples two levels were detected: H(280) at EV +0.50 eV and H(200) at EV +0.37 eV. Two different hydrogen–rhodium complexes are assigned to these levels. The thermal stability of the levels was investigated up to temperatures of 600 K.