biostudies-literatureUnknown16(1)Shen YGallium oxide (Ga₂O₃) is emerging as a promising semiconductor for next-generation power and radio-frequency electronics due to its ultra-wide bandgap and high breakdown field. Yet, its intrinsic thermal conductivity is extremely low, which causes severe self-heating and limits reliable device operation. A common approach to overcome this challenge is to integrate Ga₂O₃ with substrates of high thermal conductivity such as silicon carbide (SiC). However, weak bonding across the heterojunction interface creates large thermal resistance, preventing efficient heat removal. Here we show that constructing strong covalent bonds between Ga₂O₃ and SiC through an engineered interlayer enables both structural compatibility and efficient phonon transport. This bonding strategy increases the interface Nature communications10723https://www.ebi.ac.uk/biostudies/studies/S-EPMC12663172biostudies-literatureImproving interfacial thermal conductivity by constructing covalent bond between Ga₂O₃ and SiC.PMC12663172Guo YDing CYuan QYang MDai WLin CTHuang QJiang NLi YQi XGu LZhang QJSun FShen YMa HPChen WJJia ZfalseImproving interfacial thermal conductivity by constructing covalent bond between Ga₂O₃ and SiC.Gallium oxide (Ga₂O₃) is emerging as a promising semiconductor for next-generation power and radio-frequency electronics due to its ultra-wide bandgap and high breakdown field. Yet, its intrinsic thermal conductivity is extremely low, which causes severe self-heating and limits reliable device operation. A common approach to overcome this challenge is to integrate Ga₂O₃ with substrates of high thermal conductivity such as silicon carbide (SiC). However, weak bonding across the heterojunction interface creates large thermal resistance, preventing efficient heat removal. Here we show that constructing strong covalent bonds between Ga₂O₃ and SiC through an engineered interlayer enables both structural compatibility and efficient phonon transport. This bonding strategy increases the interface 2025-01-01T00:00:00Z2025 Nov2026-06-06T07:07:01.38Z2026-06-06T03:06:32.715ZS-EPMC126631724131531810.1038/s41467-025-65750-8