In this thesis, I contribute to two instrumental sectors in our current society -- semiconductor and energy -- by developing novel materials through advanced nanoscale engineering through atomic layer deposition (ALD). ALD is a deposition technique in vacuum, which can make highly uniform films with a thickness range of 1-100 nm on both 2-D and 3-D structured substrates. ALD chemistries enable the deposition of a wide diversity of materials. Furthermore, performing diverse ALD chemistries in single deposition is possible, leading to fabrication of both homogenous mixtures and heterogeneous structures (e.g. nanolaminate and metal/metal-oxide composite). First, I will discuss about the use of ALD to fabricate barium titanates and silicon nitrides for the applications in key semiconductor components in Chapters 2 and 3. The continuous downscaling of integrated circuits (ICs) necessitates the development of ultrathin oxides and nitrides, mainly used for dielectric materials and sidewall spacers in transistors, respectively. Oxide films with high dielectric constants (i.e. high-k) and low electrical leakage currents are essential for the applications of information storage devices such as dynamic random-access memory (DRAM). Using ALD, ultrathin (