Analysis of the basal plane dislocation density and thermomechanical stress during 100 mm PVT growth of 4H-SiC

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Details zur Publikation

Autorinnen und Autoren: Steiner J, Roder M, Nguyen BD, Sandfeld S, Danilewsky A, Wellmann P
Zeitschrift: Materials
Jahr der Veröffentlichung: 2019
Band: 12
Heftnummer: 13
ISSN: 1996-1944


Abstract

Basal plane dislocations (BPDs) in 4H silicon carbide (SiC) crystals grown using the physical vapor transport (PVT) method are diminishing the performance of SiC-based power electronic devices such as pn-junction diodes or MOSFETs. Therefore, understanding the generation and movement of BPDs is crucial to grow SiC suitable for device manufacturing. In this paper, the impact of the cooldown step in PVT-growth on the defect distribution is investigated utilizing two similar SiC seeds and identical growth parameters except for a cooldown duration of 40 h and 70 h, respectively. The two resulting crystals were cut into wafers, which were characterized by birefringence imaging and KOH etching. The initial defect distribution of the seed wafer was characterized by synchrotron white beam X-ray topography (SWXRT) mapping. It was found that the BPD density increases with a prolonged cooldown time. Furthermore, small angle grain boundaries based on threading edge dislocation (TED) arrays, which are normally only inherited by the seed, were also generated in the case of the crystal cooled down in 70 h. The role of temperature gradients inside the crystal during growth and post-growth concerning the generation of shear stress is discussed and supported by numerical calculations.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Steiner, Johannes
Professur für Werkstoffwissenschaften (Werkstoffe der Elektrotechnik)
Wellmann, Peter Prof. Dr.-Ing.
Professur für Werkstoffwissenschaften (Werkstoffe der Elektrotechnik)


Einrichtungen weiterer Autorinnen und Autoren

Albert-Ludwigs-Universität Freiburg
Technische Universität Bergakademie Freiberg


Zitierweisen

APA:
Steiner, J., Roder, M., Nguyen, B.D., Sandfeld, S., Danilewsky, A., & Wellmann, P. (2019). Analysis of the basal plane dislocation density and thermomechanical stress during 100 mm PVT growth of 4H-SiC. Materials, 12(13). https://dx.doi.org/10.3390/ma12132207

MLA:
Steiner, Johannes, et al. "Analysis of the basal plane dislocation density and thermomechanical stress during 100 mm PVT growth of 4H-SiC." Materials 12.13 (2019).

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Zuletzt aktualisiert 2019-19-07 um 17:08