Patent DE-102012024607-A1 (DE)
Title: Electronic component with Josephson junction, used detector/generator for terahertz radiation, comprises substrate and high-temperature superconductive material layer having grain boundary that forms weak bonds of Josephson junction
Inventor: FALEY MIKHAIL
IPC: H01L39/22
Filed: 2012-12-15
Abstract: The electronic component with a Josephson junction comprises substrate (1.1) with a step edge in a textured substrate surface and a layer, which is arranged on the substrate and is made of a high-temperature superconductive material. The layer has a grain boundary (1.5) at the step edge. The grain boundary forms weak bonds of the Josephson junction of the electronic component, where a- and/or b-crystal axes on the plane of the high-temperature superconductive layer is disposed perpendicular to the grain boundary with a maximum tolerance of 10[deg] on both sides of the step edge. The electronic component with a Josephson junction comprises substrate (1.1) with a step edge in a textured substrate surface and a layer, which is arranged on the substrate and is made of a high-temperature superconductive material. The layer has a grain boundary (1.5) at the step edge. The grain boundary forms weak bonds of the Josephson junction of the electronic component, where a- and/or b-crystal axes on the plane of the high-temperature superconductive layer is disposed perpendicular to the grain boundary with a maximum tolerance of 10[deg] on both sides of the step edge by texturing the substrate and/or a textured, first buffer layer (1.2) arranged between the substrate and the high-temperature superconductive layer. The first buffer layer has a thickness of = 0.5 nm. Each lattice constant of the buffer layer is integral multiple or divider of the lattice constants C of the high temperature-superconductive material layer in a layer plane, and is close to the lattice constants A and B in the plane of the high temperature-superconductive material layer. A textured second buffer layer (1.3) is arranged between the substrate and the first buffer layer or between the first buffer layer and high temperature-superconductive material layer. The second buffer layer: is formed as a sole buffer layer; is thicker (100%) than the first buffer layer; and has, in its plane, a lattice constant, which is 90-100% of the lattice constant of high temperature superconducting functional layer along one of its axes a or b in the layer plane. Textured projections and/or recesses have an average height and/or depth of 1-5 nm. A radius of curvature of the substrate at the step edge is = 1 nm. The step edge separates a flat surface area from a curved surface area. A radius of curvature of the curved area is >= 1 mu m. The step edge separates two flat areas of the substrate with a first orientation. The flat area is inclined so that the high-temperature superconducting functional layer is disposed in a region of the step edge and in a crystal orientation of the substrate. The surface of the substrate at the step edge is inclined at an angle of 35-45[deg] . A nucleation layer made of material of the functional layer is arranged between the substrate and the high temperature superconducting functional layer. The nucleation layer has a thickness of 5-20 nm that 1/3 of a thickness of the functional layer. A barrier layer is provided with a thickness of 20-40 nm, and includes a perovskite structure. An independent claim is included for a method for manufacturing a Josephson junction electronic component.