Reactive ion etching: Optimized diamond membrane fabrication for transmission electron microscopy

Abstract

Articles you may be interested inFabrication of high quality factor photonic crystal microcavities in In As P ∕ In P membranes combining reactive ion beam etching and reactive ion etching Broad ion beam milling of focused ion beam prepared transmission electron microscopy cross sections for high resolution electron microscopy Side-wall damage in a transmission electron microscopy specimen of crystalline Si prepared by focused ion beam etching Optimization of experimental operating parameters for very high resolution focused ion beam applicationsCommonly used preparation method for thin diamond membranes by focused ion beam (FIB) techniques results in surface damage. Here, the authors introduce an alternative method based on reactive ion etching (RIE). To compare these methods, cross-sectional samples are produced in single crystal diamond, a material that has generated growing interest for a variety of applications. The samples are examined by Raman spectroscopy and high-resolution transmission electron microscopy (TEM). Raman spectra indicate that the crystalline structure of the RIE-processed diamond is preserved, while the FIB-processed diamond membrane has a broad-background sp 2 feature. Atomic-resolution TEM imaging demonstrates that the RIE-based process produces no detectable damage, while the FIB-processed sample has an amorphous carbon layer of about 11 nm thick. These findings show that the RIE-based process allows the production of diamond TEM samples with reduced near-surface damage and can thus enable direct examination of growth defects and crystallographic damage induced by processes such as ion implantation and bombardment.

Coherent spin control of a nanocavity-enhanced qubit in diamond

“…This Si mask transfer process enables nano-patterning without the need of resist coating onto the substrate and is compatible with sample sizes down to several tens of square micrometers. We used oxygen plasma 11 to etch the Si mask pattern into the pre-thinned B200-nm diamond membranes (Fig. 2c).…”

Diamond Nanophotonics

“…Thin membranes produces using O 2 based plasmas have been shown to retain a high crystalline quality even very close to the surfaces exposed to the plasma: Raman measurements did not show any graphite or amorphous carbon related signals and TEM measurements reveal an intact crystal lattice for the whole etched membrane. The low level of damage is attributed to the low energy of the ions in the plasma: for typical bias voltages of 250 V, ions from the plasma can only penetrate up to 0.8 nm (two monolayers) into the diamond [119] .…”

Optomechanical Crystal Devices

“…Fabrication of the Si OMC cavities studied here benefit from highly optimized and established materials processing techniques that have been developed for the microelectronic industry and the availability of SOI wafers. Even though our focus here is on Si, similar techniques have recently been developed for materials such as diamond [53][54][55] and silicon carbide [56,57], which are expected to have excellent optical and mechanical properties. Fig.…”