In the same magazine the process is described as follows: "The Si14 silicon balance spring is produced using an advanced manufacturing process called photolithography. A silicon wafer disc is coated with a nanometre thick layer of photosensitive resist. A metal coated mask - a super detailed stencil of the springs - is then matched with the silicon disc and is exposed to ultraviolet light. Unmasked parts of the photoresist, altered at the molecular level, can then be chemically washed away while another chemical agent, with the assistance of a blast of charged ions, etches into and removes the silicon around the resist. The resist is finally removed by another agent, revealing the perfectly formed springs."
Easy peasy
Jens
Click to expand...