Towards a Fully Integrated 4H-SiC A-Plane Quantum-Chip – Transistors and Light Emitters

Abstract:

Silicon vacancies (V_Si) are relevant for quantum technologies, including sensing, computing, and communication. For the realization of quantum photonic integrated circuits (QPICs) and, therefore, co-integration of optical and electrical devices with resonant excitation through the wafer surface, a-plane 4H-SiC wafers are required. Transferring established complementary metal-oxide-semiconductor (CMOS)-compatible processes from c-plane to a-plane wafers is, therefore, a crucial step. In this work, key fabrication steps, namely ion implantation, thermal oxidation, and ohmic contact formation, were investigated for a-plane 4H-SiC substrates. To demonstrate successful process transfer, p-channel MOS field-effect transistors were fabricated and electrically characterized, showing comparable I_on/I_off ratios and mobilities to their c-plane counterparts, but with a threshold voltage shift from −7.1 V to −12.0 V on the a-plane. Additionally, tunneling diodes were realized as broadband light emitters, with a significant portion of the emission spectrum falling within the range of off-resonant excitation of V_Si centers. The devices maintained light emission functionality down to cryogenic temperatures.

• Periodical: Key Engineering Materials (Volume 1056)
• Pages: 7-15
• DOI: https://doi.org/10.4028/p-tstCC7
• Online since: May 2026
• Authors: Jannik H. Schwarberg*, Jan Dick, Alexander May, Paweł Michałowski, Birgit Kallinger, Robert Kammel, Mathias Rommel, Jörg Schulze
• Keywords: 4H-SiC A-Plane, CMOS, Integrated Light Emitter, pMOS Transistor, Silicon Vacancy, Tunneling Diode

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