AN ALL THIN-FILM RESISTIVE DC SQUID

We introduce an all thin film de resistive SQUID (de RSQUID) that work s from 4.2K down to the mK range. It consists of conventional Nb/AlO/N b tunnel junctions and an integrated Ag film resistor. With a special planar design for the resistor we achieve the necassary low value of r esistance of some 10(-5) Omega. The resistor remains normal conducting in the whole temperature range investigated, despite the proximity ef fect. The characteristic parameters of the RSQUID show negligible temp erature dependence. An integrated RSQUID could revive noise thermometr y in the mK range because of its higher signal to noise ratio and the advantages of simple read out electronics and easy handling compared t o the bulk devices used up till now.