High-Temperature Adhesive Bonding of 4H-SiC Substrates

Abstract:

This study explores the application of Polycarbosilane (PCS) as an intermediate adhesive bonding technique for 4H-SiC substrates aiming to overcome the challenges of producing high-quality and cost-effective substrates for high-power electronics. Thin layers of PCS mixed with m-xylene and AIBN (azobisisobutyronitrile) were deposited onto 4H-SiC substrates via a spin coating. For demonstration purposes, these coated 4H-SiC substrates were then bonded with another 4H-SiC substrate. A defect-free, high-temperature stable bond is facilitated by annealing at high temperatures. Effusion measurements were conducted to characterise the PCS thin films and examine the organic-inorganic transitions and the resulting outgassing at high temperatures. SEM analysis confirmed the uniformity of the bonded layer. These results demonstrate PCS’s potential in high-temperature applications and will stimulate further research exploring doped SiC bonding layers and their electrical properties.

• Periodical: Materials Science Forum (Volume 1156)
• Pages: 49-56
• DOI: https://doi.org/10.4028/p-dO4k3J
• Online since: September 2025
• Authors: Priyank Parmar*, Manoj Kumar Yadav, Christopher Zellner, Guenter Wedl, Georg Pfusterschmied, Ulrich Schmid
• Keywords: Adhesive Bonding, Effusion, Heterogenous Integration, SiC

References

[1] I. Giuseppe, et al., "Power electronics based on wide-bandgap semiconductors: Opportunities and challenges," IEEE Access, vol. 9, pp.139446-139456, 2021.

DOI: 10.1109/access.2021.3118897

[2] She X, et al., "Review of Silicon Carbide Power Devices and Their Applications.," IEEE Transactions on Industrial Electronics, vol. 64, pp.8193-8205., 2017.

DOI: 10.1109/tie.2017.2652401

[3] S. Rouchier, et al., "150 Mm SiC Engineered Substrates for High-Voltage Power Devices.," Materials Science Forum, vol. 1062, pp.131-135, 2022.

[4] W.Shan, et al., "A Novel Approach for Thin 4H-SiC Foil Realization using Controlled Spalling from a 4H-SiC Wafer," ICSCRM 2023.

DOI: 10.4028/p-8aeonp

[5] Z. Suo, et al., "Steady-state cracking in brittle substrates beneath adherent films," International Journal of Solids and Structures, vol. 25, no. 11, pp.1337-1353, 1989.

DOI: 10.1016/0020-7683(89)90096-6

[6] M. LEITGEB, et al., "Compound Semiconductor Layered Structure And Process For Preparing The Same," 2022.

[7] M. LEITGEB, et al., "Stacked Layers of Different Porosity in 4H SiC Substrates Applying a Photoelectrochemical Approach," J. Electrochem. Soc, vol. 164, p. E337, 2017.

DOI: 10.1149/2.1081712jes

[8] M. Perazzi, et al., "High-Temperature Reorganization Behavior of Single-Crystalline Porous 4H-SiC Thin Foils," Materials Science Forum, pp.43-49, 2024.

DOI: 10.4028/p-d0xoyc

[9] B. e. Kallinger, et al.,"Benchmarking Experiment of Substrate Quality including SmartSiCTM Wafers by Epitaxy in a Batch Reactor," Solid State Phenomena, vol. 342, pp.91-98, 2023.

DOI: 10.4028/p-av6tdz

[10] F. Campbell, Manufacturing Processes for Advanced Composites, 2003.

[11] [Online]. Available: https://www.starfiresystems.com/wp-content/uploads/2018/03/SMP-10.pdf.

[12] S. Kaur, et al., "Pressureless fabrication of dense monolithic SiC ceramics from a polycarbosilane," Journal of the European Ceramic Society, vol. 34, no. 15, pp.3571-3578, 2014.

DOI: 10.1016/j.jeurceramsoc.2014.05.002

[13] B. Gilvan, et al., "Polymeric and ceramic silicon-based coatings – a review," J. Mater. Chem. A, vol. 7, no. 5, pp.1936-1963, 2019.

[14] R. M. Laine, et al., "Preceramic polymer routes to silicon carbide," Chemistry of Materials, vol. 5, no. 3, pp.260-279, 1993.

DOI: 10.1021/cm00027a007

[15] L. Stöber, et al., "Nitrogen incorporation in sputter deposited molybdenum nitride thin films.," J. Vac. Sci. Technol. A 1, 2016.