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Production sequence of Si-spheres and interferometrical determination of the sphere volume

Setup for manufacturing crystalline standards put into operation.


According to the Consultative Committee for Length of the International metric Convention, the lattice constant of Silicon is recommended as a secondary definition of the unit meter for dimensional nanometrology. Based on that, it is possible to produce dimensional standards, that can be fabricated using principles of self-organization. Especially self-organization enables a significant reduction in the cost of production and verification of such standards.

Comprehensive experiments regarding the manufacture of crystalline standards have already been conducted. These proved the feasibility of a production process. The next goal is to improve and scale this process in order to bring crystalline standards to market and thus to enable a widespread use. Previous work regarding this topic has been carried out on an experimental setup, which was originally constructed for other purposes. Thus, a new setup was built with the only purpose of advancing crystalline standards. The design of the new setup is based on a modular system assembled from Standard UHV Units (SUU). Each of these modules is equipped for a specific purpose. At the moment only the module for sample preparation be means of direct-current heating is operational.

Each of the single SUU is assembled using as many standard components as possible. This enables a very cost- and time-effective construction of the setup and facilitates the repair and modification of single modules. The focus on one single preparation process allows for a reduction in complexity and simpler use of the setup. Furthermore, the production process has already been widely automatized, which reduces the training time and allows less experienced users to process samples. With this preliminary work it is now possible to evaluate the optimal process parameters and to scale up the process, so that in future several samples can be manufactured simultaneously.

The picture shows the preparation chamber and the sample holder
Fig.1: View into the preparation chamber of the new setup. A Silicon sample (marked in red, size: 13 mm x 3.2 mm) is situated inside the sample holder.



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