THIN FILM BATTERY HAVING IMPROVED BATTERY PERFORMANCE THROUGH SUBSTRATE SURFACE TREATMENT AND METHOD FOR MANUFACTURING SAME

Disclosed are a thin film battery in which a negative electrode active material and a substrate side react with each other to prevent battery performance from deteriorating, and to a method for manufacturing same. The thin film battery according to the present invention has a structure in which a negative electrode active material contacts a substrate. Here, a first surface treatment layer containing the negative electrode active material and a non-reactive material are disposed on at least the portion where the negative electrode active material contacts the surface of the substrate.