nir-vana innovation network

From the state of the art it is known that the machining of X-ray crystal optics, in particular channel X-ray monochromators made from single crystals such as Ge, Si, GaAs, InP and the like., requires high shape accuracy, low surface roughness and minimal subsurface defects of the crystal lattice of the monochromator. The surfaces of X-ray crystal optics can be machined using for example an ultra-precision CNC machine. By using a shank tool with a specially shaped diamond tip, axially fixed at the end of the shank, roughness of several nm or even below 1 nm can be achieved on open surfaces using the SPDT (Single Point Diamond Turning) method. In addition to the classical spherical surfaces, it is possible to program also aspherical surfaces, which are difficult to manufacture by stochastic technology. For nano-machining of restricted surfaces such as channels, it is not possible to use the turning (SPDT, when the tool is stationary and the workpiece is rotating). However, it is possible to use the flycutting method where the workpiece is stationary and the tool is rotating. When applying such deterministic method of machining of inner walls of channels to channel X-ray monochromators, at the depth of the channel of greater than 15 mm and a width of less than 3 mm, the shank often oscillates, resulting in undesirable surface corrugation. The above-mentioned drawbacks are substantially eliminated by the new machining method and by the construction of the tool for machining of inner walls of channels in fragile materials in the nanometer region. The novelty of the technology lies in the use of an innovative deterministic method of surface machining using a special tool with a shaped tip from diamond single crystal. The basis of the new solution of the tool design lies in the fact that the tool consists of a fully or partially disc-shaped body with a central clamping opening and at least one groove in one axial line on the perimeter of the body into which a diamond single crystal is soldered from the side with at least one shaped tip exceeding the groove length. The fully or partially disc-shaped body may be a complete disk, or it may be a disk with e.g. 45 ° angle sector or up to 360 ° angle sector. The central opening is for fixing the disc to the spindle of the nano-machining center. The diamond single crystal is soldered from the side so that the walls of the channel can be machined.

The institute is looking for partners to cooperate with via financial agreement or license agreement. Details about preferred types of cooperation are more specified in the Partner Sought.

Advantages & innovations

• achievement of significantly higher shape accuracy (flatness of inner walls of the monochromator), • achievement of low surface roughness (below 5 nm rms), • achievement of minimal subsurface defects of the crystal lattice (for a possible re-polishing, a quarter of the time of chemical re-polishing is sufficient compared to the stochastic method), • in the case of the solution with two diamond tips, achievement of extreme parallelism of inner walls of the channel, unachievable by other methods.

Stage of development

Available for demonstration

Partner sought

Type: The institute is seeking an industrial partner for licensing or financing the technology. Applications: The industrial applicability of the tool for machining of inner walls of channels in fragile materials in the nanometer region is in the field of channel X-ray monochromators for high-resolution X-ray diffractometry (both laboratory and synchrotron), and secondary also for neutron diffractometry and ion optics. Other applications of the tool are assumed for ultra-precision machining in confined channel-type spaces in precision and fine mechanics, microfluidics and optics. Role of partner: - financial agreement - the financing for the further development of this technology is sought, - license agreement - an industrial partner for licensing of this technology is sought