Impact of ALD-Deposited ZnO Interlayer on the Dielectric Response and Electric Modulus of Al/p-Si Junctions
13. International Conference on Materials Science and Nanotechnology for Next Generation (MSNG-2026), Adıyaman, Türkiye, 2 - 04 Eylül 2026, cilt.1, sa.1, ss.1-9, (Tam Metin Bildiri)
- Yayın Türü: Bildiri / Tam Metin Bildiri
- Cilt numarası: 1
- Basıldığı Şehir: Adıyaman
- Basıldığı Ülke: Türkiye
- Sayfa Sayıları: ss.1-9
- Yozgat Bozok Üniversitesi Adresli: Evet
Özet
In this study, Al/ZnO/p-Si heterojunction structures were fabricated by depositing a 5 nm ZnO interlayer on p-type Si (100) substrates via atomic layer deposition, followed by thermal evaporation of Al top contacts. Frequency- and voltage-dependent dielectric and electrical characteristics were systematically examined through admittance spectroscopy across 1 kHz–1 MHz and –2 to +2 V. Capacitance–voltage and conductance–voltage measurements revealed pronounced low-frequency dispersion, attributed to interface trap states at the ZnO/p-Si junction that respond to the AC signal only at lower frequencies. Derived dielectric parameters, including effective complex permittivity components, loss tangent, and electric modulus, indicated a dielectric response consistent with Maxwell–Wagner-type interfacial polarization alongside trap-assisted relaxation. Cole–Cole analysis revealed a broadened distribution of relaxation times, which can be attributed to defect-mediated relaxation dynamics, plausibly associated with hopping processes within the ultrathin ALD-grown ZnO layer. These findings offer critical insight into the interfacial charge dynamics and relaxation behavior of ZnO/p-Si heterostructures, underscoring the importance of understanding interfacial polarization and defect dynamics for the design and optimization of sub-10 nm oxide-based heterojunction devices.
Keywords: Atomic layer deposition (ALD), ZnO/p-Si heterojunction, Admittance spectroscopy, Dielectric, Interface states.