MEASUREMENT OF THE ELECTRIC CURRENT PROFILE OF PARTICLE CLUSTERS IN GASES AND IN A VACUUM

摘要

The invention relates to the measurement of current profiles of free-flying ion or electron clusters which impinge on a detector electrode of a Faraday detector. The detector electrode here consists of a large number of structural elements in a bipolar arrangement, where neighboring structural elements have opposite polarities and structural elements with the same polarity are electrically connected, and a voltage is applied between neighboring structural elements so that before ions or electrons impinge on the detection electrode, they are essentially deflected onto the structural elements with one of the two polarities. If the current profiles on the structural elements of the two polarities are measured separately and subtracted from each other, a current profile which corresponds to the pure ion or electron current profile is obtained without using a screen grid.

主权项

1. Method for the measurement of the electric current profile of free-flying clusters of electrically charged particles which impinge on a detector electrode, wherein:
the detector electrode consists of a number of structural elements in a bipolar arrangement, where neighboring structural elements have opposite polarities and all structural elements of the same polarity are connected together; a voltage is applied between the two groups of structural elements of different polarities so that shortly before the incoming particles impinge, they are deflected in such a way that they hit only the structural elements of one polarity; the current profiles at the structural elements of both polarities are each measured separately; and the two current profiles are subtracted from each other, where the image current profiles which are formed in both groups of structural elements in practically the same way are subtracted from each other and a current profile is obtained which corresponds to the pure particle current.