An employment of atomic layer deposition (ALD) method into the semiconductor devices is becoming pivotal because of the excellent attributes offered by ALD process such as good coverage and low impurity level. The ALD technique provides thin film depositions of nanoscale high-permittivity (k) gate dielectrics, metal electrodes, deep metal contact fill, and liners and/or barrier layers of Cu. This paper will review and discuss about the properties of thin ALD films for direct metal gate and capacitor electrodes. As a direct metal gate electrode application, various ALD metal electrodes such as TiN, TaN, and WN films were evaluated on thin SiO2 and high-k gate dielectric films for metal-oxide-semiconductor (MOS) capacitors and transistors. The effects of impurities and process conditions on the MOS devices will be discussed. MOS devices gated with ALD thin films demonstrated much lower defect densities than those with sputtered films by means of lower interface trap density and orders of magnitude lower leakage current. This is most likely a result of the relatively damage-free ALD deposition process. Equivalent oxide thickness of sub-nanometer (< 1nm) was attained with ALD-metal/high-k stack against the thermal budget of complementary MOS device fabrication. Additionally, an application of ALD-TiN film into a capacitor electrode for extremely high aspect ratio (~ 70:1) trench capacitors for sub-100nm trench DRAM devices will be presented. It is necessary to keep focusing on the development of various ALD materials systems to meet device requirements such as relevant work function and stability across the required thermal cycle.