Open AccessEffects of Chemical-Electrical and Mechanical Parameters on Electrical-induced Chemical Mechanical Polishing of GaN
Author(s) -
Zhao Ding,
Shiwei Niu,
Qingyu Yao,
Y. Wang,
Huaijun Guan,
Dong Zhao,
Zebin Yu
Publication year - 2021
Publication title -
ecs journal of solid state science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.488
H-Index - 51
eISSN - 2162-8777
pISSN - 2162-8769
DOI - 10.1149/2162-8777/ac4215
Subject(s) - materials science , etching (microfabrication) , chemical mechanical planarization , polishing , wafer , isotropic etching , oxidizing agent , cathodoluminescence , gallium nitride , electrochemistry , metallurgy , composite material , nanotechnology , chemical engineering , optoelectronics , chemistry , electrode , organic chemistry , layer (electronics) , luminescence , engineering
Overcoming the low fabricating efficiency of traditional chemical mechanical polishing (CMP) for Gallium nitride (GaN) is a challenge owing to its high hardness, high brittleness, and chemical inertness. Here, electrochemical etching is proposed to increase the material removal rate and acquire a high-quality surface on GaN wafers. To reveal the synergistic etching mechanism of oxidizing agent and corrosion inhibitor on the GaN wafers, electrochemical etching experiments were carried out. The optimal etching solution contained 4 wt% H 2 O 2 and 10 mmol l −1 purified terephthalic acid. Experiments with various polishing parameters were comparatively investigated to verify the auxiliary effect of etching and determine the ideal parameters. Cathodoluminescence spectroscopy shows that the electrochemical etching removes the SSDs completely and the CMP process with befitting parameters does not induce supernumerary SSDs.