Electron Beam Induced Current (EBIC) and Electron Beam Absorbed Current (EBAC), also called Resistive Contrast Imaging (RCI), are two techniques used to locate and analyze failures inside semiconductor devices. Both methods take advantage of the interaction of the SEM electron beam with the device under test (DUT) to reveal information to the failure analysis investigator.
EBIC provides the means to visualize and quantitatively determine properties like the diffusion length of transistor p-n junctions. With Imina Technologies high positioning resolution nanomanipulators, probe needles are placed in contact with a junction to measure the induced current. The EBIC system amplifies the point probe measurements and synchronizes them to the electron beam position. This information can then be mapped and overlaid to the microscope secondary electron image with the EBIC system for visualization.
The EBAC technique is based on a similar principle as EBIC. The electron beam of the SEM scans the DUT and injects charges absorbed by metal lines under the surface. A current is then induced and measured by a probe placed with a miBot nanomanipulator at contact level. As for EBIC, the probed signal can be overlaid on the secondary electron image. Direct comparison of this image with layout details allows the investigator to easily detect and finely localize shorts and/or opens.
The measurements presented in the application note were performed with Imina Technologies Nanoprobing SEM solution loaded with four miBot™ and the device under test. The platform was installed in a FEI Quanta 650 ESEM. Electrical measurements were performed with a Keithley 4200-SCS semiconductor parametric analyzer. EBIC and EBAC analyses were made with a Point Electronic DISS 5.
Experiment realized at
Fraunhofer CAM, Halle, Germany (www.cam.fraunhofer.de)