Fabrication methods for a flexible device having an array of pixel units for retina prosthesis are described. The fabrication method may comprise forming layered structures including the array of pixel units over a substrate, each pixel unit comprising a processing circuitry, a micro electrode and a photo sensor. A first set of biocompatible layers may be formed over the layered structures. In one embodiment, the substrate may be thinned down to a controlled thickness of the substrate to allow bending of the substrate to the curvature of a retina. A second set of biocompatible layers may be formed over the thinned substrate. In some embodiments, the second set of biocompatible layers may be in contact with the first set of biocompatible layers to form a biocompatible seal wrapping around the device to allow long˙-term contact of the device with retina tissues. Micro electrodes of the pixel units may be exposed through the openings of these biocompatible layers.本發明揭露一種用於人工視網膜且具有畫素單元陣列之可撓性元件的製造方法。此方法包含在基板上形成具有畫素單元陣列的疊層結構。每一畫素單元包含處理電路、微電極以及光感元件。第一組生物可相容層形成於疊層結構上。在一實施例中,薄化該基板至一控制厚度,使該基板可彎曲至一視網膜曲度。在該薄化的基板上形成一第二組生物相容層。在某一實施例中,該第二組生物相容層在該基板處接觸該第一組生物相容層,以形成一包覆該可撓性元件之密閉式生物相容層,使該可撓性元件長期接觸視網膜組織。該畫素單元的該微電極會透過該生物可相容層暴露出來。500J‧‧‧結構503‧‧‧矽層509‧‧‧氧化/金屬層527‧‧‧阻障層529‧‧‧生物可相容高分子層(II)
