Dopant Selective Photoelectrochemical Etching of SiC
Open Access
- 1 March 2023
- journal article
- research article
- Published by The Electrochemical Society in Journal of the Electrochemical Society
- Vol. 170 (3), 036508
- https://doi.org/10.1149/1945-7111/acc553
Abstract
Single crystalline 4H-SiC is a wide-gap semiconductor with optical properties that are poised to enable new applications in MEMS and quantum devices. A number of key hurdles remain with respect to the micro and nano-fabrication of SiC to prepare precise photonic structures with nanometer-scale precision. These challenges include development of a fast, scalable etching process for SiC capable of producing a sub-nanometer roughness semiconductor surface while simultaneously reducing the total thickness variation across a wafer. Our investigation into UV photoelectrochemical processing of SiC reveals high dopant-type selectivity and the advantage of multiple etch stops to reduce layer thickness variation. We demonstrate dopant-type selectivities >20:1 using a single step and a >100x reduction in surface variation by combining two etch stops. Moreover, the etch rate is fast (>4 mu m h(-1)) and the etched surface is smooth (similar to 1 nm RMS). These results demonstrate a scalable path to the fabrication of precise nanoscale SiC structures and electronic devices that will enable the next generation of MEMS and photonic quantum devices.Keywords
This publication has 25 references indexed in Scilit:
- Reduced Plasma-Induced Damage to Near-Surface Nitrogen-Vacancy Centers in DiamondNano Letters, 2015
- Polytype control of spin qubits in silicon carbideNature Communications, 2013
- Secondary electron doping contrast: Theory based on scanning electron microscope and Kelvin probe force microscopy measurementsJournal of Applied Physics, 2010
- Smooth Top-Down Photoelectrochemical Etching of m-Plane GaNJournal of the Electrochemical Society, 2009
- Anodic etching of SiC in alkaline solutionsJournal of Micromechanics and Microengineering, 2007
- Wet etching of GaN, AlN, and SiC: a reviewMaterials Science and Engineering: R: Reports, 2005
- Photoelectrochemical etching of n-type 4H silicon carbideJournal of Applied Physics, 2004
- Dopant-selective etch stops in 6H and 3C SiCJournal of Applied Physics, 1997
- Dopant Selective Photoelectrochemical Etching of GaAs HomostructuresJournal of the Electrochemical Society, 1991
- Effect of carrier confinement on the laser-induced etching of GaAs/AlGaAs heterostructuresApplied Physics Letters, 1989