The effect of various electrodes (Al, W, TiN) deposited by evaporation (Al) and sputtering (W, TiN) on the electrical characteristics of thermal thin film (15–35 nm) Ta 2O 5 capacitors has been investigated. The absolute level of leakage currents, breakdown fields, mechanism of conductivity, dielectric constant values are discussed in the terms of possible reactions between Ta 2O 5 and electrode material as well as electrode deposition process-induced defects acting as electrically active centers. The dielectric constant values are in the range 12–26 in dependence on both Ta 2O 5 thickness and gate material. The results show that during deposition of TiN and Al a reaction that worsens the properties of Ta 2O 5 occurs while there is not an indication for detectable reduction of Ta 2O 5 when top electrode is W, and the leakage current is 5–7 orders of magnitude lower as compared to Al and TiN-electroded capacitors. The high level of leakage current for TiN and Al gate capacitors are related to the radiation defects generated in Ta 2O 5 during sputtering of TiN, and damaged interface at the electrode due to a reaction between Al and Ta 2O 5, respectively. It is demonstrated that the quality of the top electrode affects the electrical characteristics of the capacitors and the sputtered W is found to be the best. The sputtered W gate provides Ta 2O 5 capacitors with a good quality: the current density <7 × 10 −10 A/cm 2 at 1 V (0.7 MV/cm, 15 nm thick Ta 2O 5). W deposition is not accompanied by an introduction of a detectable damage leading to a change of the properties of the initial as-grown Ta 2O 5 as in the case of TiN electrode. Damage introduced during TiN sputtering is responsible for current deterioration (high leakage current) and poor breakdown characteristics. It is concluded that the sputtered W top electrode is a good candidate as a top electrode of storage capacitors in dynamic random access memories giving a stable contact with Ta 2O 5, but sputtering technique is less suitable (favorable) for deposition of TiN as a metal electrode due to the introduction of radiation defects causing both deterioration of leakage current and poor breakdown characteristics.