Full area transparent contacts are the next step in order to enhance the efficiency of silicon based passivated emitter rear cells. Here we present a full area contact based on Al₂O₃ and reduced TiO_x. The thin Al₂O₃ acts as passivating tunneling layer, whereas the TiO_x is used for charge carrier transport. This work provides a way to enhance the conductivity of TiO_x by forming gas annealing (FGA) and doping with tantalum. Furthermore, it addresses the native SiO_x without chemical treatment. A thin titanium interlayer (Ti-IL) serves this purpose. Current-voltage measurements reveal a contact resistance of 30 Ωcm² for 50 nm of pure TiO_x. Ta-doping combined with a 6 nm thick Ti-IL reduces the contact resistance by two orders of magnitude down to 0.36 Ωcm². The passivation by an Al₂O₃/TiO_x layer stack leads to an excellent surface recombination velocity (SRV) of 5.6 cm/s with only 3 nm Al₂O₃ but results in a large contact resistance of about 100 Ωcm². This contact resistance can be reduced by three orders of magnitude down to 0.25 Ωcm² including a 10 nm Ti-IL while still providing a sufficient SRV of about 60 cm/s. The absorption coefficient of 6.3×10⁵ cm⁻¹ inhibits the usage as front contact for solar cells. However, it could be used as a backside contact, since the transmission is less important on the backside of a monofacial solar cell.