Control of Inclined Sidewall Angles of 4H-SiC Mesa and Trench Structures

Hidenori Koketsu; Tomoaki Hatayama; Kento Amishima; Hiroshi Yano; Takashi Fuyuki

doi:10.4028/www.scientific.net/MSF.679-680.485

Paper Titles

Recovery of Ohmic Contacts Formed on C-Face 4H-SiC Following High Temperature Post-Processing
p.469

Investigation of Epitaxial SiC PiN Diodes with Variable Mesa Height
p.473

Influence of the Masking Material and Geometry on the 4H-SiC RIE Etched Surface State
p.477

Thinning of 2-Inch SiC Wafer by Plasma Chemical Vaporization Machining Using Cylindrical Rotary Electrode
p.481

Control of Inclined Sidewall Angles of 4H-SiC Mesa and Trench Structures
p.485

TEM Observation of 8 Deg Off-Axis 4H-SiC (0001) Surfaces Planarized by Catalyst-Referred Etching
p.489

Abrasive-Free Planarization of 3-Inch 4H-SiC Substrate Using Catalyst-Referred Etching
p.493

Reduction of Charge Trapping Sites in Al₂O₃/SiO₂ Stacked Gate Dielectrics by Incorporating Nitrogen for Highly Reliable 4H-SiC MIS Devices
p.496

Oxidation Process by RTP for 4H-SiC MOSFET Gate Fabrication
p.500

HomeMaterials Science ForumMaterials Science Forum Vols. 679-680Control of Inclined Sidewall Angles of 4H-SiC Mesa...

Control of Inclined Sidewall Angles of 4H-SiC Mesa and Trench Structures

Abstract:

The sloped sidewall angle in 4H-SiC mesa structure could be controlled by a thermal etching at 900oC in chlorine (Cl2) based ambience. 4H-SiC C face with 8o off substrate was used. The SiO2 layers for the etching mask were formed by a deposited SiO2 layer or a thermally oxidized layer. Thermal etching was carried out at Cl2 ambience at 900oC for 15 minutes. The surface morphologies of the mesa structures were observed with the scanning electron microscope (SEM) and atomic force microscope (AFM). The sloped angles at the mesa sidewalls using deposited SiO2 mask and thermal SiO2 mask were about 23o and 60o, respectively. These results mean that the angle of sloped sidewall can change by mask fabrication method.