Defects in 4H silicon carbide

• Published in: Physica. B, Condensed matter Vol. 308; pp. 675 - 679
• Main Authors: Bergman, J.P., Storasta, L., Carlsson, F.H.C., Sridhara, S., Magnusson, B., Janze’n, E.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2001
• Subjects: Defects; SiC; Stacking faults; SiC; Stacking faults; Defects
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/S0921-4526(01)00790-6

We present experimental results related to several different intrinsic defects that in different ways influence the material properties and are therefore technologically important defects. This includes the so-called D1 defect which is created after irradiation and which is temperature stable. From the optical measurements we were able to identify the D1 bound exciton as an isoelectronic defect bound at a hole attractive pseudo-donor, and we have been able to correlate this to the electrically observed hole trap HS1 seen in minority carrier transient spectroscopy (MCTS). Finally, we describe the formation and properties of a critical, generated defect in high power SiC bipolar devices. It is identified as a stacking fault in the SiC basal plane. It can be seen as a local reduction of the carrier lifetime, in triangular or rectangular shape, which explains the enhanced forward voltage drop in the diodes. The entire stacking faults are also optically active as can be seen as dark triangles and rectangles in low temperature cathodo-luminescence, and the fault and their bounding partial dislocations are seen and identified using synchrotron topography.