METHODS AND APPARATUS FOR ION BEAM ANGLE MEASUREMENT IN TWO DIMENSIONS

摘要

An angle measurement system (100) for an ion beam includes a flag (120) defining first (140) and second features (142), wherein the second feature has a variable spacing from the first feature, a mechanism (122) to translate the flag along a translation path so that the flag intercepts at least a portion of the ion beam (62), and a sensing device (123, 124) to detect the ion beam for different flag positions along the translation path and produce a sensor signal in response to the detected ion beam. The sensor signal and corresponding positions of the flag are representative of a vertical beam angle of the ion beam in a vertical plane . The sensing device may include a mask and a mechanism to translate the mask in order to define a beam current sensor on a portion of an associated Faraday sensor.