Proven Power Cycling Reliability of Ohmic Annealing Free SiC Power Device through the Use of SmartSiC^TM Substrate

Abstract:

The Smart Cut^TM technology enables the combination of a high quality single crystal SiC layer onto a low resistivity handle wafer (<5mOhm.cm), allowing device optimization as well as the reduction of device’s conduction and switching losses. On this new SmartSiC^TM substrate, the sheet resistance of the back side contact after metal deposition, without anneal, is about 10x lower than the annealed back side contact on 4H-SiC. Schottky-barrier vertical structures thinned down to 250μm were prepared for power cycling tests (PCT) measurements. Up to 250 k cycles, the devices remained within the specifications of AQG324 for samples prepared from SmartSiC^TM substrates. We are demonstrating here that in addition to a higher current rating (up to 20%), the SmartSiC^TM substrate enables a device fabrication simplification by skipping the annealing of the back-side ohmic contact, without compromising either the back-side contact resistance or the assembly PC_sec reliability.

• Periodical: Materials Science Forum (Volume 1092)
• Pages: 201-207
• DOI: https://doi.org/10.4028/p-777hqg
• Online since: June 2023
• Authors: Eric Guiot*, Frédéric Allibert, Jürgen Leib, Tom Becker, Walter Schwarzenbach, Carsten Hellinger, Tobias Erlbacher, Séverin Rouchier
• Keywords: Low Resistivity, Ohmic Contact, Power Cycling, SiC Layer Transfer, Smart Cut^TM, SmartSiC^TM

References

[1] S. Rouchier et al., in Materials Science Forum 1662-9752, Vol. 1062, pp.131-135

[2] U. Scheuermann et al., Microelectronics Reliability 2010;50(9-11):1203–9

[3] E. Guiot et al., in proceedings of APEC2022, March (2022)

[4] C. Hellinger et al., Materials Science Forum, Vol. 1004, pp.718-724

[5] E. Guiot et al., in proceedings of PCIM 2022, May 2022.

[6] IMAPS Wire Bonding Workshop, January 21-22, 2014.

[7] U. Waltrich et al., CIPS 2018 - pp.547-551, (2018)

[8] F. Roccaforte et al., Chapter in International Journal of High Speed Electronics and Systems · June 2006.