Characterization and Reduction of Defects in 4H-SiC Substrate and Homo-Epitaxial Wafer

Long Yang; Li Xia Zhao; Hui Wang Wu; Yafei Liu; Tuerxun Ailihumaer; Balaji Raghothamachar; Michael Dudley

doi:10.4028/www.scientific.net/MSF.1004.387

Paper Titles

Near Infrared Photoluminescence of N_CV_Si^- Centers in High-Purity Semi-Insulating 4H-SiC Irradiated with Energetic Charged Particles
p.355

The Effect of γ-Ray Irradiation on Optical Properties of Single Photon Sources in 4H-SiC MOSFET
p.361

4H-SiC Epi-Ready Substrate Qualification by Using Mirror Electron Microscope Inspection System
p.369

Photoluminescence Analysis of Individual Partial Dislocations in 4H-SiC Epilayers
p.376

Characterization and Reduction of Defects in 4H-SiC Substrate and Homo-Epitaxial Wafer
p.387

Synchrotron X-Ray Topography Study on the Relationship between Local Basal Plane Bending and Basal Plane Dislocations in PVT-Grown 4H-SiC Substrate Wafers
p.393

BPD-TED Conversion in the SiC Substrate after High-Temperature Si-VE
p.401

Dislocations Analysis on Implanted (p-Type and n-Type) 4H-SiC Epi-Layer by KOH Molten Etching
p.408

TEM Studies on the Microstructure of m-Face Grown 4H-SiC by Solution Growth
p.414

HomeMaterials Science ForumMaterials Science Forum Vol. 1004Characterization and Reduction of Defects in...

Characterization and Reduction of Defects in 4H-SiC Substrate and Homo-Epitaxial Wafer

Abstract:

4H-SiC substrates and homo-epitaxial layers were obtained using the traditional methods of physical vapor transport and chemical vapor deposition. Defect morphology has been studied using both Synchrotron White Beam X-ray Topography and Monochromatic Beam X-ray Topography. Molten KOH etching method was adopted to further investigate the dislocation behavior mechanisms. Deflected dislocations were observed at the periphery regions in both substrate and epitaxial wafers. 3C polytypes and half loop arrays were observed in the 4H-SiC epitaxial wafer. It is also found that the majority of basal plane dislocations are converted to threading edge dislocations in the epitaxial wafer samples. The proportion of BPD to TED conversion depends on the surface step morphology and growth mode in epitaxial growth which in turn depends on the C/Si ratio. By the optimization of etching time prior to epitaxy and C/Si ratio, high-quality epitaxial wafers with extremely low basal plane dislocations densities (＜0.1 cm^-2) was obtained.