NOVELTY - The structure has organic semiconductor substrates (116,118) that are separated from one another. Several localized spacers connect the substrates together. The localized spacers include a lateral dimension less than 350 nm. The localized spacers comprise several self-assembled nano-dots of height dimension 1 to 50 nm, which is formed on a surface of the substrates. A sub-micron separation distance between the substrates is configured to tunnel the carriers between the substrates.    USE - Electronic transfer device structure such as heat transfer device structure, integrated circuit device package, thermo-photovoltaic device, thermionic emitter device, thermo-tunneling device, photonic transfer device and substrate-to-substrate coupling structure (all claimed), used in thermal compliant interface, display, single junction and multi-junction solar cell, electronics packaging and nano-electro-mechanical systems, refrigeration, energy conversion, and proximity lithography fields.    ADVANTAGE - The self-assembled and non-self-assembled nano-dots form a small gap separating two substrates so as to promote electron tunneling, hole tunneling, infrared coupling, and heat transfer across the gap. The depletion region formed in the substrates can limit the dark current to acceptable values without use of the insulating regions. The nano-dots can be removed so as to limit the dark current to acceptable values without use of the insulating regions. The electrons tunnel carry the heat energy across the separation distance so as to create an electric potential to drive an external electric load, while phonons or thermal waves are not able to tunnel. Efficient heat-to-electric conversion can be obtained. The nano-gaps are used between two surfaces of bulk materials so as to permit unique combinations of materials electrically coupled across the gap. The stress and thermal mismatch can be avoided.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) charge transfer method; and    (2) method for transferring heat between substrates.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the photon coupler device.    Photonic transfer device (110)    Electrical contact (112)    Nano-dot spacer (114)    Substrates (116,118)    Electrical insulator (119)