▎ 摘　　要

NOVELTY - The sensor has a diode that is provided with a two-dimensional barrier layer based on a layer arrangement of a metal electrode (20), electrical barrier (22) and a graphene layer (24). A surface layer (26) is located above and on the graphene layer and configured for electrically reacting to photons and/or the deposited foreign matter which forms the surface of the sensor. USE - Sensor for detecting photons incident on surface and/or foreign matter accumulating on surface e.g. skin in healthcare applications. ADVANTAGE - A sensor is easy to manufacture, and realizes a low dark current and high sensitivity with a quick response time. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for detection of photons and/or accumulated foreign matter with sensor. DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a sensor. Metal electrode (20) Electrical barrier (22) Graphene layer (24) Surface layer (26) Voltage source (28)