NOVELTY - The device (100) has a back contact layer (110) formed above a substrate (105). An absorber layer (120) is formed above the back contact layer. A buffer layer (130) is formed above the absorber layer. A front contact layer (160) is formed above the buffer layer. A plasmonic nanostructured layer (140) comprises multiple nano-particles (150). The plasmonic nanostructured layer is formed between a topmost back contact layer surface and the absorber layer, where the absorber layer is made of material selected from a group consisting of copper, gallium, indium, aluminum, selenium or selenide.    USE - Thin film photovoltaic device i.e. thin film solar cell. Uses include but are not limited to a silicon thin film solar cell, a copper indium gallium selenide (CuInGaSe2) solar cell, a heterojunction with intrinsic thin (HIT) layer solar cell, organic thin-film solar cell and copper indium gallium diselenide thin-film solar cell.    ADVANTAGE - The device has higher conversion efficiency and higher photovoltaic efficiency with thinner designs, and allows the light to travel along the photovoltaic device and bounce between the substrate and the nano-particles enabling the photovoltaic device to absorb more light. The device avoids the need to use sputtering or thermal evaporation processes in forming the plasmonic metallic nano-particle layer so as to avoid high costs associated with the uses.    DETAILED DESCRIPTION - The nano-particles include graphene nanoplatelets, carbon nanotubes (CNT) or silver nano-particles. An INDEPENDENT CLAIM is also included for a method for manufacturing a thin film photovoltaic device.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a portion of a thin film photovoltaic device during fabrication.    Thin film photovoltaic device (100)    Substrate (105)    Back contact layer (110)    Absorber layer (120)    Buffer layer (130)    Plasmonic nanostructured layer (140)    Nano-particles (150)    Front contact layer (160)