Interest of Using a Micro-Meter Spatial Resolution to Study SiC Semi-Conductor Devices by Optical Beam Induced Current (OBIC)

In this paper we present a new test bench called micro-OBIC used to characterized wide band gap semi-conductor. Micro-OBIC allows to get an Optical Beam Induced Current (OBIC) signal with a microscopic spatial resolution. We used micro-OBIC to characterize peripheral protection such as MESA, JTE or JTE in high voltage SiC device.

Near Breakdown Voltage Optical Beam Induced Current (OBIC) on 4H-SiC Bipolar Diode

This paper presents OBIC measurements performed at near breakdown voltage on two devices with different JTE doses. Overcurrent has been measured either at the JTE periphery or at the P+ border. Such overcurrent is present due to the electric field enhancement near the breakdown voltage. This hypothesis is proved by the electroluminescence. TCAD simulation of two different JTE doses yielded similar results to the OBIC measurements.

Multiphoton OBIC for Device Characterization and Defect Localization

Applications of MpOBIC (Multi-photon Optical Beam Induced Current) are discussed for use in defect localization. The MpOBIC signals in a ring oscillator under static conditions are examined and demonstrate the superior optical resolution of the system over traditional OBIRCH. A 5-fin diode test structure is examined under passive conditions, demonstrating that true multi-photon OBIC has occurred from the backside. The same diode is examined in forward bias, and the resulting discussion concludes that both OBIC and OBIRCH signals are present in the sample. Thus, we claim that both OBIC and OBIRCH signals can provide device characterization information from an MpOBIC system.