Expansion of Shockley stacking faults in 4H-SiC achieved by the radiation-enhanced glide of 30-Si(g) partial dislocations has been investigated by photoluminescence experiments. The enhancement rate of the dislocation glide that was induced by light illumination in the present study was found to be governed directly by the light intensity, not by the photogenerated carriers. This fact indicates that the glide enhancement in 4H-SiC is not explained by the widely speculated mechanism that the electronic energy released on recombination of photoexcited electron-hole pairs is utilized to assist the dislocation glide. A photoionization of dislocations is proposed to be the cause of the glide enhancement.

Anomalous expansion of stacking faults (SFs) induced in 4H-SiC under electronic excitations is driven by an electronic force and is achieved by enhanced glide of partial dislocations. An experimental attempt to separate the two physically different effects has been made by conducting photoluminescence (PL) mapping experiments which allowed simultaneous measurements of partial dislocation velocity and SF-originated PL intensity the latter of which is proposed to be related to the driving force for SF expansion through the density of free excitons planarly confined in the SF.

We investigated expansion velocities of Shockley stacking faults (SSFs) in 4H-silicon carbide under laser illumination using photoluminescence methods. The experiments showed that the velocity of SSF expansion or the glide velocity of SSF-bounding 30°-Si(g) partial dislocations (PD) is supralinearly dependent on the excitation intensity. We estimated sample temperature by analyzing the broadening of band-edge emission and concluded that the lattice heating by laser illumination is not the cause of the enhanced dislocation glide. The supralinear dependence can be accounted for by a photo-induced sign reversal of the effective formation energy of SSF acting as the driving force of SSF expansion under the illumination.