Ion beam incidence angle and beam divergence monitor

摘要

A device for measuring an incidence angle of an ion beam impinging a planar substrate includes an aperture plate having an aperture for intercepting the ion beam and passing a beam portion therethrough, and a sensor located in the substrate plane or a plane parallel thereto behind the aperture plate and having a length along which the beam portion impinges on the sensor at a location which is a function of the incidence angle of the ion beam, the sensor configured to produce a sensor signal indicative of the location of impingement of the beam portion on the sensor and representative of incidence angle. A computing unit may be configured to compare the sensor signal to a predetermined function for determining the incidence angle of the ion beam. Spaced apart sensing devices may be used to determine beam divergence.