NOVELTY - The electronic apparatus comprises an enclosure that includes an electronically active material (2) in its interior, and an oxygen ion pump (8) for removing oxygen from the apparatus. The pump is attached to the interior of the enclosure, and includes a cathode and an anode located at two opposite ends of an oxygen ion-conductive material. A part of the cathode outwardly faces an inside of enclosure, and a part of the anode is outwardly directed to an exterior of the enclosure. The enclosure includes a substrate (3), a cap (4) and an adhesive (5) sealed together.    USE - The electronic apparatus is useful as organic or polymeric organic electroluminescence devices, organic FETs, organic integrated circuits, organic thin film transistors, organic light emitting transistors, organic solar cells, organic optical detectors, organic laser diodes, organic field-quench devices, light emitting electrochemical cells, organic plasmon-emitting devices and organic photovoltaic elements or devices and organic photoreceptors (all claimed).    ADVANTAGE - The electronic apparatus has high temperature stability and reduced permeability for oxygen, air or water vapor.    DETAILED DESCRIPTION - The electronic apparatus comprises an enclosure that includes an electronically active material (2) in its interior, and an oxygen ion pump (8) for removing oxygen from the apparatus. The pump is attached to the interior of the enclosure, and includes a cathode and an anode located at two opposite ends of an oxygen ion-conductive material. A part of the cathode outwardly faces an inside of enclosure, and a part of the anode is outwardly directed to an exterior of the enclosure. The enclosure includes a substrate (3), a cap (4) and an adhesive (5) sealed together. The pump is arranged in a region of the adhesive, and is provided as a layer partially located on the substrate and/or the cap. The substrate and/or the cap is made of glass, ceramic, polymer or plastics. The oxygen ion-conducting material includes a solid electrolyte. The electronically active material includes an oxygen sensitive material, organic electronically active material such as a light-emitting material, and/or quantum dot containing material.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of an electronic device.    Electronically-active material (2)    Substrate (3)    Cap (4)    Adhesive (5)    Oxygen ion pump. (8)