OBIRCH:
When a laser beam, finely focused by an objective lens, irradiates a sample surface, various kinds of signals are emitted as result of interaction between the incident laser beam and the sample. Visualization of these phenomena can be made by detecting these various photo effects caused by the interaction and by displaying them on a vewing screen synchronized with the scanning of the laser beam.
When the laser beam with energy higher than the band gap energy of the pn junction irradiates semiconductor devices, electron-hall pairs are generated and they flow in the semiconductor to make electron current. Detecting this current and displaying on a viewing screen, we obtain OBIC image, and they are used for failure analysis of semiconductor devices. Applying a bias voltage to the wire in the wiring area of semiconductor, we can detect a current change due to the resistance change by scanning the focused laser beam over the surface. This is the Optical Beam Induced Resistance Change (OBIRCH).
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