Optical beam-induced current

Optical beam induced current (OBIC) is a semiconductor analysis technique performed using laser signal injection. The technique induces the creation of electron–hole pairs in the semiconductor sample through the use of a light source (often times a laser source is used). This technique is used in semiconductor failure analysis in order to locate buried diffusion regions, damaged junctions and gate oxide shorts.

Use of OBIC for FIB milling end-point detection

The OBIC technique may be used to detect the point at which a focused ion beam (FIB) milling operation in bulk silicon of an IC must be terminated (also known as endpoint). This is accomplished by using a laser to induce a photocurrent in the silicon while simultaneously monitoring the magnitude of the photocurrent by connecting an ammeter to the device's power and ground. As the bulk silicon is thinned, the photocurrent is increased and reaches a peak as the depletion region of the well to substrate junction is reached. This way, endpoint can be achieved to just below the well depth and the device remains operational.

References

• Template:Harvard reference.
• Template:Harvard reference.

Publications in this field

Manfred Frischholz, Jörg Seidel, Adolf Schoner, Ulf Gustafsson, Mietek Bakowski, Kenneth Nordgren and Kurt Rottner (1998). "JTE concept evaluation and failure analysis: OBIC measurements on 4H Sic p+-n diodes". Proceedings of 1998 International Symposium on Power Semiconductor Devices & ICs, Kyoto: 391–394.{{cite journal}}: CS1 maint: multiple names: authors list (link)