The present invention concerns a reservoir assembly for use in three-dimensional (3D) printing for building a 3D object, which includes a top frame that may be filled with liquid material, and a tensioned film being held underneath the top frame. The tensioned film may be air permeable and elastic at the same time, wherein surfaces of the tensioned film are micro textured so that the tensioned film becomes optically clear when it contacts with the liquid material. The tensioned film minimizes the creation of bubbles between the top and bottom surfaces. This also helps blurring the boundaries thereby enhancing the surface finish of the fabricated parts.