Speaker
Description
The General Low Mass (GLM) beamline of ISOLDE is dedicated to collecting and handling radioactive isotopes.
The currently still used ion implantation chamber is a single vacuum chamber equipped with a turbo pump capable of reaching 1E-5 mbar, often relying on the beamline vacuum pump to achieve its optimal pressure of 1E-6 mbar.
The new ion implantation chamber features a load-lock system with two sub-chambers—the implantation chamber and the sample loading/unloading chamber—connected by a DN200 gate valve, each independently evacuated by its own turbo pump (HiPace 700 and 1200 respectively). This setup allows for quick vacuuming down to 1E-6 mbar within minutes. Additionally, the implantation process is automated with computer-controlled stepper motors that (a) transfer samples between the two sub-chambers and (b) adjust the collimator in the implantation sub-chamber, enabling optimization of the incoming radioactive ion beam, and (c) an Einzel lens that allows for the focusing of the beam downstream.
The advantages of the new ion implantation chamber are 1) the introduction of the load-lock mechanism between the two sub-chambers ensures that the implantation sub-chamber is kept at operational pressure ( < 1E-6 mbar) and not vented for rapid sample change and implantation (for more frequent implantations), 2) user-friendliness, in which the automation afforded by the motors decrease the risk of user error, 3) safety, inbuilt in both hardware and software, in which minimization of mechanical contact between the GLM users and the new ion implantation chambers will lead to radiological exposition reduction."
