Magnetic Photoelectron Energy Analyzer for IC Laser Testing
Original Publication Date: 1986-Jun-01
Included in the Prior Art Database: 2005-Mar-09
This article describes an improved technique for collecting photoelectrons in an energy analyzer. Photoelectron energy analyzers use the same design as the secondary electron energy analyzer currently. A problem in the case of laser approach is that in order to focus the laser beam down to (or close to) the diffraction limit, the lens subtends a large solid angle above the device under test. All photoelectrons, which constitute the signal for voltage contrast of integrated circuit laser testing, liberated by a UV laser and emitted into the solid angle subtended by the lens are lost. This reduces the signal-to-noise ratio of laser IC testing by 1-3 orders of magnitude. This problem can be greatly improved by using a magnetic field to guide photoelectrons to the photoelectron detector.