Search

The present invention relates to a free-standing single crystalline diamond part and a single crystalline diamond part production method. The method includes the steps of: - providing a single crystalline diamond substrate or layer; - providing a first adhesion layer on the substrate or layer; - providing a second adhesion layer on the first adhesion layer: - providing a mask layer on the second adhesion layer; - forming at least one indentation or a plurality of indentations through the mask layer and the first and second adhesion layers to expose a portion or portions of the single crystalline diamond substrate or layer; and - etching the exposed portion or portions of the single crystalline diamond substrate or layer and etching entirely through the single crystalline diamond substrate or layer.

The present invention concerns a single crystalline diamond optical element production method. The method includes the steps of: ‐ providing a single crystalline diamond substrate or layer; ‐ applying a mask layer to the single crystalline diamond substrate or layer; ‐ forming at least one or a plurality of indentations or recesses through the mask layer to expose a portion or portions of the single crystalline diamond substrate or layer; and ‐ etching the exposed portion or portions of the single crystalline diamond substrate or layer.

The present invention concerns a layer or substrate flattening method comprising the steps of: - providing a layer or substrate (1) to be flattened; - measuring a topography or surface profile of at least one area (3) of the layer or substrate to be flattened; - providing at least one etch layer (5A) on at least one area of the layer or substrate to be flattened; - defining a topography (7) of said at least one etch layer, said topography to be exposed to etching; and - etching the at least one etch layer comprising the defined topographic surface and the at least one area of the layer or substrate to provide a flattened surface on the at least one area of the layer or substrate.

Diamond is an exceptional material that has recently seen a remarkable increase in interest in academic research and engineering since high-quality substrates became commercially available and affordable. Exploiting the high refractive index, hardness, laser-induced damage threshold, thermal conductivity and chemical resistance, an abundance of applications incorporating ever higher-performance diamond devices has seen steady growth. Among these, diffractive optical elements stand out-with progress in fabrication technologies, micro- and nano-fabrication techniques have enabled the creation of gratings and diffractive optical elements with outstanding properties. Research activities in this field have further been spurred by the unique property of diamond to be able to host optically active atom scale defects in the crystal lattice. Such color centers allow generation and manipulation of individual photons, which has contributed to accelerated developments in engineering of novel quantum applications in diamond, with diffractive optical elements amidst critical components for larger-scale systems. This review collects recent examples of diffractive optical devices in diamond, and highlights the advances in manufacturing of such devices using micro- and nano-fabrication techniques, in contrast to more traditional methods, and avenues to explore diamond diffractive optical elements for emerging and future applications are put in perspective.

The present invention concerns an optical grating comprising a body defining a first external surface and a second external surface. The first external surface defines a periodic structure comprising a plurality of elongated protrusions and a plurality of elongated recesses or depressions. The periodic structure is configured to receive an incident first electromagnetic wave propagating in an input propagation direction and to transmit the first electromagnetic wave to the second external surface for transmission through the second external surface. The periodic structure is configured to reflect, back into the input propagation direction, an incident second electromagnetic wave propagating in an opposite direction. The first electromagnetic wave has a wavelength lower that of the second electromagnetic wave.

Diamond is an exceptional material - hard, stiff, transparent, which makes it ideal for the fabrication of optical and mechanical systems that take advantage of these properties. Diamond is not only "better", but it offers the possibility of integrating bright colour centres. These optically active defects can be exploited for a variety of applications, including the study of fundamental science, magnetometry, biosensing and new types of lasers. Despite the attractive properties of diamond for optics, no standard platform exists to create photonic circuits and devices. This thesis shows the realisation of a diamond-on-insulator photonics platform, that aims to combine the versatility of the silicon-on-insulator photonics with the capability of performing diamond science in single crystal guided-wave devices. The diamond-on-insulator substrate is achieved via ion implantation-based cut of a single crystal membrane and bonding of the membrane to an insulator layer. This approach provides a monolithic fabrication process that scales to commercial exploitation, bringing convenient access to the study of diamond light-matter interactions without requiring custom substrate fabrication. Furthermore, the possibility of releasing the diamond devices adds access to freestanding structures, opening the way to diamond micro-opto-electro-mechanical systems and optomechanics. Diamond also makes an excellent microoptics substrate, due to its high laser damage threshold, transparency and high refractive index, which is an attractive combination for high-power, compact optical systems operating in the UV, visible and near-infrared. Different diamond etching techniques are developed and investigated in this thesis, that enable the realisation of unique features. These techniques are employed to create diamond diffractive microoptical components, which are then characterised, showing high-quality surfaces that closely match the designed features, indicating reliable fabrication and resulting in excellent optical performance. These devices have applications in high power beamsplitters, beam shapers and compact spectrometers.

We demonstrate a novel method for fabricating single crystal diamond diffraction gratings based on crystallographic etching that yields high-quality diffraction gratings from commercially available diamond plates. Both V-groove and rectangular gratings were fabricated and characterised using scanning electron microscopy and atomic force microscopy, revealing angles of 57° and 87° depending on the crystal orientation, with mean roughness below Ra = 5 nm on the sidewalls. The gratings were also optically characterised, showing good agreement with simulated results. The fabrication method demonstrated in this contribution shows the way for manufacturing high-quality diamond diffractive components that surpass existing devices both in quality and manufacturability.