The Japan Society of Applied Physics

2023 International Conference on Solid State Devices and Materials

2023 International Conference on Solid State Devices and Materials

Sep 5, 2023 - Oct 31, 2023
Nagoya Congress Center

11:45 AM - 12:00 PM

[E-6-05] Controlling SiO 2 Thin Film Charge and Interface Defect Density on Germanium

○Hanchen Liu1, Toni P Pasanen1, Oskari Leiviskä1, Joonas Isometsä1, Tsun Hang Fung1, Marko Yli-Koski1, Mikko Miettinen2, Pekka Laukkanen2, Ville Vähänissi1, Hele Savin1 (1. Aalto Univ. (Finland), 2. Univ. of Turku (Finland))

https://doi.org/10.7567/SSDM.2023.E-6-05

Surface passivation of germanium by plasma enhanced atomic layer deposited (PEALD) SiO2 alone has shown a thickness-independent behavior because of the low bulk charge density. Nevertheless, adding an ALD Al2O3 capping layer improves the interface quality and also significantly enhances the positive SiO2 bulk charge density from 4.4×1016 cm-3 to 2×1017 cm-3. By adjusting the SiO2 layer thickness we also observe a surface barrier hysteresis and interface defect density shift. Consequently, by varying the SiO2 thickness we can control interfacial properties and improve surface passivation.