The excellent field-effect passivation provided by aluminum oxide (Al₂O₃) on germanium surfaces relies on the high negative fixed charge present in the film. However, in many applications, a neutral or a positive charge would be preferred. Here, we investigate the surface passivation performance and the charge polarity of plasma-enhanced atomic layer deposited (PEALD) silicon oxide (SiO₂) on Ge. The results show that even a 3 nm thick PEALD SiO₂ provides a positive charge density (Q_tot, ∼2.6 × 10¹¹ cm⁻²) and a relatively good surface passivation (maximum surface recombination velocity SRV_max ∼16 cm/s). When the SiO₂ thin film is capped with an ALD Al₂O₃ layer, the surface passivation improves further and a low midgap interface defect density (D_it) of ∼1 × 10¹¹ eV⁻¹ cm⁻² is achieved. By varying the SiO₂ thickness under the Al₂O₃ capping, it is possible to control the Q_tot from virtually neutral (∼2.8 × 10¹⁰ cm⁻²) to moderately positive (∼8.5 × 10¹¹ cm⁻²) values. Consequently, an excellent SRV_max as low as 1.3 cm/s is obtained using optimized SiO₂/Al₂O₃ layer thicknesses. Finally, the origin of the positive charge as well as the interface defects related to PEALD SiO₂ are discussed.