Patent ID: 8597872

Claim:
A method for production of a ring-shaped and non-self-supporting medical marker having a wall thicknesses of less than 20 μm and comprising an X-ray-opaque material, wherein the method comprises the following steps: a) applying a mask with ring patterns formed in registration on two surfaces of a conductive plate-shaped substrate by photolithography; b) depositing the X-ray-opaque material of the marker in a borehole in the substrate; c) removing the mask; and d) eliminating the substrate such that the marker is non-self-supporting, wherein step a) comprises: i) coating the substrate with a photoresist; ii) exposing parts of the photoresist to light to form the mask; iii) developing the photoresist; and iv) removing non-exposed parts of the photoresist by forming the borehole through the substrate and at least one ring-shaped free space of the mask, such that the substrate lying under the at least one ring-shaped free space is removed, and wherein step b) comprises: aa) passing a flow of electrolyte through the mask and the borehole; and bb) depositing the X-ray-opaque material from the electrolyte onto a wall of the borehole by galvanic deposition.