OBIC technique applied to wide bandgap semiconductors from 100 K up to 450 K

Abstract

Wide bandgap semiconductors have recently become more used in the power electronics domain. They are predicted to replace the traditional silicon especially for high voltage and/or high frequency devices. Device design has shown a big progress in the last two decades. Substrates up to six inches of diameter are now commercialized with very low defect densities. Such a development is due to many studies that never stop. Among these studies, the ones that allow an excess of charge carriers in the space charge region (like OBIC-Optical Beam Induced Current-and EBIC-Electron Beam Induced Current-) are efficient to analyze the variation of electric field as function of the voltage and the beam position. This paper shows OBIC technique applied to wide bandgap semiconductors based devices. OBIC cartography gives an image of the electric field in the device, and the analysis of OBIC signal help determining some characteristics of the semiconductors like minority carrier lifetime and ionization rates. These are key parameters to predict device switching behavior and breakdown voltage.

Experimental and simulation results of optical beam induced current technique applied to wide bandgap semiconductors

“…Figure 14.b) shows 1D-OBIC scan for low reverse voltage (VR = 10 V). Results show an OBIC signal appearing at both edges of the MESA [14]. a) b) Fig.…”

“…15: Cross section a) and 2D-OBIC cartography b) on Schottky diamond diode for a reverse voltage of 5 V using the UV laser (diameter of the diode is 150 µm). Sweeping was fixed to 50 µm in both directions [14].…”

An editorial on the recent advances in high and low temperature electronics

“…The application of Optical-Beam-Induced Current (OBIC) to the characterization of wide bandgap semiconductors up to 400 K is described by Hamad et al [16]. It is shown that OBIC enables one to determine some of the key characteristics of semiconductors, like the minority carrier lifetime and ionization rates.…”

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

“…This induced current is then directly related to the electrical field in the device. OBIC is a non-destructive technique, which has been previously successfully used to characterize High Voltage (HV) SiC devices [2,3,4,5]. In order to fully benefit of the advantages provided by WBG semiconductors materials and to avoid premature breakdown of the high voltage devices, it is mandatory to have efficient peripheral protections such as a combination of MESA with JTE or MESA with JTE and JTE rings as described in [6].…”

“…The induced current is directly related to the electrical field in the device. The OBIC, is a non-destructive characterization technique, which has been previously successfully used to characterize High Voltage (HV) SiC devices [1,2,3,4].…”