HCl Etching Behavior on Low-Tilt-Angle and Step-Free 4H-SiC Surfaces

Andrew J. Trunek; J. Anthony Powell; Philip G. Neudeck; M. Mrdenovich

doi:10.4028/www.scientific.net/MSF.615-617.593

Paper Titles

Phase Inhomogeneity and Electrical Characteristics of Nickel Silicide Schottky Contacts Formed on 4H-SiC
p.577

Aluminum Doping by Low-Temperature Homoepitaxial Growth for Ni Ohmic Contacts to p-Type 4H-SiC
p.581

Process Optimization for High Temperature SiC Lateral Devices
p.585

A Comprehensive Study of Hydrogen Etching on the Major SiC Polytypes and Crystal Orientations
p.589

HCl Etching Behavior on Low-Tilt-Angle and Step-Free 4H-SiC Surfaces
p.593

Comparison between Polishing Etching of On and Off-Axis C and Si-Faces of 4H-SiC Wafers
p.597

Electrochemical Polishing of p-Type 4H SiC
p.601

The Effect of Slurry Composition and Flatness on Sub-Surface Damage and Removal in Chemical Mechanical Polishing of 6H-SiC
p.605

Spectroscopic Measurement of Electric Discharge Machining for Silicon Carbide
p.609

HomeMaterials Science ForumMaterials Science Forum Vols. 615-617HCl Etching Behavior on Low-Tilt-Angle and...

HCl Etching Behavior on Low-Tilt-Angle and Step-Free 4H-SiC Surfaces

Abstract:

We report on new observations made, when 4H-SiC, Si-face substrate mesas, having either low tilt-angle (< 1°) with steps or step-free top surfaces, were exposed to three separate HCl etching conditions for five minutes at temperatures of 1130°C, 1240°C and 1390°C. We observed that HCl was ineffective at 1130°C, as etching was incomplete with abundant surface contamination. At 1240°C, screw dislocations were aggressively etched by HCl, while multiple shallow flat-bottomed etch pits were formed on step-free mesa surfaces. At 1390°C, step-flow etching dominated as large etch pits were formed at screw dislocations and previously step-free surfaces etched inward from mesa edges to form parallel rows of organized steps.