Thermalization arrangement at cryogenic temperatures

A thermalization arrangement at cryogenic temperatures, wherein the arrangement comprises:

• a dielectric substrate layer on which substrate a device/s or component/s are positionable, and
• a heat sink component attached on another side of the substrate,
• the arrangement further comprising:
• a conductive layer between the substrate layer and the heat sink component,
• a joint between the substrate layer and the conductive layer having minimal phonon thermal boundary resistance, wherein the minimal phonon thermal boundary resistance is defined to be below 10 K4/(W/cm2)/T3, and in which energy of conductive layer phonons are arranged to be absorbed by electrons, and
• another joint between the conductive layer and the heat sink component being electrically conductive,
• wherein the substrate layer has acoustic properties and the conductive layer has acoustic properties, and wherein some or all of the acoustic properties of the substrate layer and the conductive layer are such that phonons that passed through the joint between the substrate layer and the conductive layer are absorbed by the conductive layer.