Nondestructive Evaluation of Photoelectrical Properties of a PVT Grown Bulk 15R-SiC Crystal

Gediminas Liaugaudas; Kęstutis Jarašiūnas; Nikolaos Tsavdaris; Eirini Sarigiannidou; Didier Chaussende

doi:10.4028/www.scientific.net/MSF.806.65

Paper Titles

Investigation of Aluminum Incorporation in 4H-SiC Epitaxial Layers
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Raman Investigation of Heavily Al Doped 4H-SiC Layers Grown by CVD
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Improvement of the Specific Contact Resistance on P-Type 4H-SiC by Using a Highly P-Typed Doped 4H-SiC Layer Selectively Grown by VLS Transport
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Interface Shape: A Possible Cause of Polytypes Destabilization during Seeded Sublimation Growth of 15R-SiC
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Nondestructive Evaluation of Photoelectrical Properties of a PVT Grown Bulk 15R-SiC Crystal
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Potentialities of AlGaN/GaN Heterostructures Grown on 2°-Off 4H-SiC Substrates
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Polarization Engineering of Al(Ga)N/GaN HEMT Structures for Microwave High Power Applications
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High Quality Graphene Formation on 3C-SiC/4H-AlN/Si Heterostructure
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Synthesis and Characterization of (3-Aminopropyl)Triethoxysilane-Modified Epitaxial Graphene
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HomeMaterials Science ForumMaterials Science Forum Vol. 806Nondestructive Evaluation of Photoelectrical...

Nondestructive Evaluation of Photoelectrical Properties of a PVT Grown Bulk 15R-SiC Crystal

Abstract:

Investigation of excess carrier dynamics in a 15R-SiC bulk layer grown by physical vapour transport (PVT) on 15R-SiC substrate has been carried out using pump-probe techniques: an interband carrier injection by a picosecond laser pulse and measuring the induced absorption and diffraction of a probe beam. For this task, differential transmittivity (DT) and light induced transient grating (LITG) techniques were used. Room temperature carrier lifetime varied in the 3 ns 8 ns range at excess carrier densities above ΔN₀ = 7×10¹⁷ cm^-3 and was ascribed to the recovery time of optically recharged carrier traps, and their activation energy of E_a = 75 meV was determined. The presence of recharged traps caused the injection-dependence of the diffusion coefficient D, whereby its value dropped below 0.1 cm²/s at ΔN₀ < 1×10¹⁸ cm^-3 and gradually increased up to 0.7 cm²/s at higher injections. At elevated temperatures (300 K < T < 700 K), when the traps are thermally activated, the diffusivity increased up to ~ 1.5 cm²/s and was independent on ΔN₀. The overgrown layer parameters were comparable to those of the used 15R PVT seed.