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What are Ion Selective Aperture Arrays (ISAA)?

Simply stated, ISAAs are a novel way to transmit ions generated at AP through the conductance limiting pathway into vacuum. Conventional tubes and apertures are effectively ion gates which limit ion transmission from AP sources to only a few nanoamps at best. The unique property of ISAAs is their ability to control the electric field through the entire pathway into vacuum. Figure 1 is a simulation of ion transmission through a laminated array of openings into vacuum. Observe that few ions are lost to the walls. This is in stark contrast to the conventional tube or aperture approaches where most ions are lost (>99%) to the entrance and wall regions of the source and conductance path. ISAAs are a effective technology for increasing ion transmission efficiency, sensitivity, and reducing contamination (charging) from AP sources. Additional details of this technique are discussed in our October 2006 Feature Article "How Do We Eliminate Ion Losses at AP?: Keeping the Barn Doors Open: ."

We are developing a complete product line of conductance arrays for a variety of gas loads and pumping conditions. In addition, we provide custom design and fabrication capabilities to address your specific research needs.

Figure 1- Simulation of ion motion from AP to vacuum through an ion selective aperture array.