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Different properties of the reported stacking faults (SFs) and that both these types of SF are present in the material after electrical degradation of pin diodes are shown. One is caused by perfect dislocations, deflected or misfit dislocation that had dissociated into two partial dislocations. The partials are assumed to be close to each other with a separation below the detection limit of the SWBT measurements. Thus, enough energy is provided and the leading partial moves away from the other partial and forms the extended SF.

The partial dislocations that border triangle or parallelogram-shaped stacking faults formed during the degradation of p-n diodes fabricated on 4H-SiC wafers were determined by transmission X-ray topography to be dislocation loops of Burgers vector 1/3<101¯0>, the Shockley partial type, consistent with previously reported TEM results. Some were separated from axial screw dislocations also present in the sample, indicating that the axial dislocations were not involved in the loops' nucleation, while others were seen to have interacted during their growth with the axial screw dislocations, distorting their shapes from those of ideal parallelograms. © 2003 Elsevier Science B.V. All rights reserved.

In this work we present experimental results of several defects in 4H Sic that are of interest both from a fundamental and physical point of view. And also of great importance for device applications utilizing the Sic material. These defects include the temperature stable so called D1 defect, which is created after irradiation. This optical emission has been identified as an isoelectronic defect bound at a hole attractive pseudodonor, and we have been able to correlate this to the electrically observed hole trap HS1 seen in minority carrier transient spectroscopy (MCTS). It also includes the UD1 defect observed using absorption and FTIR and which is believed to be responsible for the semi-insulating behavior of material grown by the High temperature, HTCVD technique. Finally, we have described the formation and proper-ties of critical, generated defect in high power Sic bipolar devices. This is identified as a stacking fault in the Sic basal plane, using mainly white beam synchrotron Xray topography. The stacking fault is both optically and electrically active, by forming extended local potential reduction of the conduction band.