Etching Kinetics of (100) Single Crystal Diamond Surfaces in a Hydrogen Microwave Plasma, Studied with In Situ Low‐Coherence Interferometry
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2017-08-16 |
| Journal | physica status solidi (a) |
| Authors | V. Yu. Yurov, E.V. Bushuev, A. P. Bolshakov, E. E. Ashkinazi, I.A. Antonova |
| Institutions | Institute of Radio-Engineering and Electronics, Harbin Institute of Technology |
| Citations | 30 |
Abstract
Section titled “Abstract”A low‐coherence interferometry (LCI) was used to measure in situ the etch rate (ER) of synthetic single crystal (SC) diamonds in H 2 microwave plasma, at substrate temperatures in the broad range of 800-1370 °C. The method allows the collection of the kinetic data on a single sample without switching off the plasma. (100)‐orientated SC plates of CVD and IIa type HPHT diamond were systematically etched in pure hydrogen at pressure p = 130 Torr and microwave power density of ≈300 W cm −3 . The activation energies E a of 42 ± 5 and 32 ± 4 kCal mol −1 have been determined for the CVD and HPHT substrates. An enhanced etching rate of a subsurface defected layer with thickness of ∼1 μm or less, formed upon polishing of the samples, is revealed. Surface morphology, roughness, and the shape of etch pits produced by a selective etching of defects, were characterized with optical profilometry. CH and dimer C 2 radicals were detected in the H 2 plasma with optical emission spectroscopy, as a result of the diamond etching, and the emission intensity of these species was linked to the substrate etch rate.