▎ 摘　　要

NOVELTY - The apparatus i.e. graphene-based MIM diode (518), has two layers of electrically conductive material separated by a layer of optically transparent electrically insulating material, where the apparatus is configured such that electrons are able to tunnel from one of the layers of electrically conductive material through the layer of electrically insulating material to the other layer of electrically conductive material. An antenna allows a flow of electrons when the antenna is illuminated by electromagnetic radiation (516), where the apparatus is formed on a supporting substrate. USE - Apparatus e.g. diode such as graphene-based metal-insulator-metal (MIM) diodes, for use in a photodetector and a rectenna (all claimed) of a hand-portable electronic device i.e. personal digital assistant. Can also be used as p-n junction diode and Schottky junction diode. ADVANTAGE - The apparatus ensures that the graphene exhibits greater electron mobility than electrode materials currently being used in the diodes so as to prevent the electrons from recombining with holes created by an incident radiation before crossing the junction, thus increasing efficiency of the electronic device. The apparatus ensures that optically transparent graphene allows thicker layers of graphene to be used in forming the electrodes of the diode, which increases the probability of photo emission, so that a mean free path of electrons in the graphene is 65 micrometer, and the electrons can be generated up to 65 micrometer from an insulating barrier and can be able to cross the barrier to the other electrode, thus reducing roughness of the insulating layer, which results in better tunneling behavior and reliability by increasing thickness of the electrodes. DETAILED DESCRIPTION - The supporting substrate is an electrically insulating/optically transparent supporting substrate. The electromagnetic radiation is selected from a group consisting of UV, infra red, visible light, microwave, radio and X-ray. The supporting substrate is a glass substrate and an oxidized silicon substrate. The former layer of electrically conductive material is made from graphene, and the latter layer of electrically conductive material is made of chromium, gold, aluminum, nickel, copper, platinum, tungsten and indium tin oxide. The layer of electrically insulating material is made of aluminum oxide, hafnium dioxide, boron nitride and diamond-like carbon. INDEPENDENT CLAIMS are also included for the following: (1) a method for making a diode apparatus (2) a method for controlling a diode apparatus. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a photo detector comprising a diode. Graphene electrode (504) Electromagnetic radiation (516) Graphene-based MIM diode (518) Variable voltage source (519) Ammeter (520)