Accumulation of photoinduced carriers at the SiO 2 /Si interface observed through graphene transport

• Published in: Japanese Journal of Applied Physics 2024-02, Vol.63 (2), p.2
• Main Authors: Miura, Jin, Inamura, Fumiyuki, Ikuta, Takashi, Maehashi, Kenzo, Ikushima, Kenji
• Format: Article
• Language: English
• ISSN: 0021-4922; 1347-4065
• DOI: 10.35848/1347-4065/ad1778

The accumulation of photoinduced carriers at the SiO 2 /Si interface was observed via graphene transport. CVD graphene was transferred to a lightly p-doped silicon substrate with a SiO 2 dielectric layer and served as a charge sensor for detecting the accumulation of photoinduced carriers at the SiO 2 /Si interface. The sample was cooled to 4.2 K to realize an undoped silicon substrate without intrinsic carriers. Photoexcited carriers in the undoped silicon substrate were collected at the SiO 2 /Si interface via a gate voltage and the carrier polarity was controlled well by the polarity of the gate voltage set during the light illumination. The photoinduced carrier density was determined by the number of photons incident on the silicon substrate with a photon–electron conversion efficiency of about 0.036. These results may provide polarity control of the conduction channel (n- or p-type) in standard Si-MOS structures, paving the way for optically programmable Si-CMOS.