Using Atomic Layer Deposition Techniques to Synthesize Complex Thin Films for Electrode Protection Layers

Atomic Layer Deposition (ALD) enables creating uniform, conformal thin films with precise thickness control at the monolayer level. The solid surface is exposed to the precursors; each of which adsorbs with the chemically reactive site`s surface. The precursors are introduced onto the substrate simultaneously and are separated via inert gas purges to ensure avoiding interactions of supporting solvents with substrates. In addition, the deposition temperature is lowered in comparison to the chemical vapor deposition (CVD).

We propose taking existing, well-characterized ALD processes and combining them to create a multicomponent process. This multicomponent process enables achieving accurate and precise control over the composition and the properties of the layered thin films.

We have developed a process for depositing thin films of lithium vanadium phosphate (Li_xPVO₄). This was accomplished by using the processes used for trimethyl phosphate (TMP), vanadium oxytriisopropoxide (VTOP) and lithium tretbutoxide (LiO^tBu). The thin film characterized using both microscopic and spectroscopic tools such as Rutherford Backscattering Spectrometry (RBS), XPS, HR-TEM.

Our research goal is to use this state-of-the-art technique for artificial SEI (ASEI) fabrications directly on electrochemically active surfaces while mitigating the degradation of the active materials.