Origin of Large Bumps Abnormally Grown on 4H-SiC Epitaxial Film by Adding HCl Gas with High Cl/Si Ratio in CVD Process

Yoshiaki Daigo; Akio Ishiguro

doi:10.4028/www.scientific.net/MSF.1004.91

Paper Titles

X-Ray Topography Characterization of Large Diameter AlN Single Crystal Substrates
p.63

Highly Reliable 4H-SiC Epitaxial Wafer with BPD Free Recombination-Enhancing Buffer Layer for High Current Applications
p.71

Improvement of Repeatability on N-Type 4H-SiC Epitaxial Growth by High Speed Wafer Rotation Vertical CVD Tool
p.78

Achievement of Low Carrier Concentration of High-Uniformity SiC Films Grown by High Speed Wafer Rotation Vertical CVD Tool
p.84

Origin of Large Bumps Abnormally Grown on 4H-SiC Epitaxial Film by Adding HCl Gas with High Cl/Si Ratio in CVD Process
p.91

Revisiting the Site-Competition Doping of 4H-SiC: Cases of N and Al
p.96

Corona Assisted Tuning of Gallium Oxide Growth on 3C-SiC(111)/Si(111) Pseudosubstrates
p.102

Prospects of Bulk Growth of 3C-SiC Using Sublimation Growth
p.113

3C-SiC Bulk Growth: Effect of Growth Rate and Doping on Defects and Stress
p.120

HomeMaterials Science ForumMaterials Science Forum Vol. 1004Origin of Large Bumps Abnormally Grown on 4H-SiC...

Origin of Large Bumps Abnormally Grown on 4H-SiC Epitaxial Film by Adding HCl Gas with High Cl/Si Ratio in CVD Process

Abstract:

4H-SiC homo-epitaxial film was grown by adding HCl gas with a high Cl/Si ratio in CVD process, and defect formation and origin of the defect were investigated by confocal differential interference contrast (CDIC) microscope, PL imaging and normal differential interference contrast (DIC) microscope. It was found that a large number of large bumps are formed on the film grown at a high Cl/Si ratio of 30, and a large number of PL defects on bare substrate before the film growth are also observed. Coordinates where the bumps on the film are observed were good agreement with those where the PL defects on the bare substrate are observed. An etch pit sample on reproduced substrate from which epitaxial film was removed was fabricated by etching process using molten KOH+Na₂O₂, and some types of etch pits which might be originated from threading edge dislocations (TEDs), threading screw dislocations (TSDs) and basal plane dislocations (BPDs) in the substrate were observed. The coordinates where the etch pits on the reproduced substrate are observed were also good agreement with those where the bumps on the epitaxial film are observed. Therefore, it was clarified that a large number of the bumps abnormally grown on the epitaxial film are originated from the dislocations in the substrate.