Fabrication of (111)-faced single-crystal diamond plates by laser nucleated cleaving

Abstract

Single-crystal diamond plates with surfaces oriented in a (111) crystal plane are required for high-performance solid-state device platforms ranging from power electronics to quantum information processing architectures. However, producing plates with this orientation has proven challenging. In this paper, we demonstrate a method for reliably and precisely fabricating (111)-faced plates from commercially available, chemical-vapor-deposition-grown, type-IIa single-crystal diamond substrates with (100) faces. Our method uses a nanosecond-pulsed visible laser to nucleate and propagate a mechanical cleave in a chosen (111) crystal plane, resulting in faces as large as 3.0 mm × 0.3 mm with atomically flat surfaces, negligible miscut angles, and near zero kerf loss. We discuss the underlying physical mechanisms of the process along with potential improvements that will enable the production of millimeter-scale (111)-faced single-crystal diamond plates for a variety of emerging devices and applications.

Photonic devices fabricated from (111)‐oriented single crystal diamond

“…To confirm the (111) membrane orientation, X-ray diffraction (XRD) and electron backscattered diffraction Figure 1D shows an XRD spectrum of the original bulk single crystal diamond with a pronounced peak at 2θ = 44 , confirming the (111) orientation of the crystal. 21 Figure 1E shows an EBSD map recorded from the overgrown membrane, confirming further that it is single crystal (111)-oriented diamond through analysis of kikuchi pattern information derived from back scattering of electrons in SEM.…”

“…19 However, despite the remarkable progress in nanofabrication of diamond cavities, 8,20 all photonic resonators to date were fabricated from (100)-oriented diamond, primarily because this is the most common orientation provided by commercial suppliers and the difficulty in engineering and polishing (111)-oriented crystals. 21 This, however, limits the potential coupling strength of many color centers to cavities, since most centers studied to date have dipoles oriented along the <111> direction, and the dipole overlap with the cavity field is therefore not optimal in cavities fabricated from (100)-oriented diamond. Conversely, in (111)-oriented diamond, the overlap is optimal, and superior Purcell enhancement is expected.…”

“…Last, if the photonic resonator is carefully designed with coupled directional emission, one can achieve high cavity cooperativity and realise advanced quantum phenomena such as single photon switch with a solid state system [19]. However, despite the remarkable progress in nanofabrication of diamond cavities [8,20], all photonic resonators to date were fabricated from (100)-oriented diamond, primarily because this is the most common orientation provided by commercial suppliers and the difficulty in engineering and polishing (111) oriented crystals [21]. This, however, limits the potential coupling strength of many color centers to cavities since most centers studied to date have dipoles oriented along the <111> direction, and the dipole overlap with the cavity field is therefore not optimal in cavities fabricated from (100)-oriented diamond.…”

Spin Readout Techniques of the Nitrogen-Vacancy Center in Diamond

“…Using a 100x, NA = 0.9 air objective, Jamali et al [ 48 ] showed that proper alignment of the dipole and optical axes results in a increase in collected photons, corresponding to an SNR increase of ≈1.3. Although the production of (111)-faced diamonds is traditionally a laborious and expensive process, recent developments of laser-nucleated-cleaving techniques [ 49 ] provide an attractive alternative. In this technique, a series of laser pulses is used to nucleate and propagate cleaves along desired (111) planes within a standard (100)-faced diamond, resulting in large, flat, (111)-faced plates even without any polishing.…”

Materials challenges for quantum technologies based on color centers in diamond

“…Furthermore, different surface orientations may allow for access to different chemical terminations; for example chemical groups that are sterically prohibited on the (100) surface may be permitted on (111) surfaces [86]. Such surfaces are difficult to prepare because polishing is more challenging for these orientations, but recent work has shown that near-atomically smooth surfaces are possible with cleaving [87].…”