A border trap (BT) evaluation method was established for SiO2/GeO2Ge gate stacks by using deep-level transient spectroscopy with a lock-in integrator. Ge metal-oxide-semiconductor capacitors (MOSCAPs) with SiCVGeCVGe gate stacks were fabricated by post-passivation thermal oxidation. The interface trap (IT) and BT signals were successfully separated based on their different dependences on the intensity of injection pulses. By using p-type MOSCAPs, BTs at the position of 0.4 nm from GeO2Ge interface were measured. The energy of these BTs was centralized at the position near to the valence band edge of Ge, and the density (Nbt) was in the range of 1017-1018 cm-3. For n-type MOSCAPs, BTs at the position range of 2.8-3.4 nm from the GeO2/Ge interface were measured. The energy of these BTs were distributed in a relatively wide range near to the conduction band edge of Ge, and the Nbt was approximately one order of magnitude higher than those for p-MOSCAPs. We also found that Al post metallization annealing can passivate both ITs and BTs near to the valence band edge of Ge but not those near to the conduction band edge.