Integrated circuit - having ion-sensitive liq. sensor and reference electrode having gold@ layer

摘要

Integrated circuit (I) has an ion-sensitive liq. sensor and a reference electrode (II) which has an Au layer bordering on the liq. The improvement is that a) (I) is enclosed in a housing (III); b) (III) has a window within which (II) is positioned; c) (I) is covered with a protective layer (IV); d) (II) has, below its Au layer, a layer of Ni or Ni/Cr which is positioned on layer (IV); e) (II) is positioned on the front side of (I) and is photolithographically structured; f) (II) extends to a contacting area outside the window of (III); and g) (I), with the exceptions of contact surfaces of (II) and of the active sensor surfaces of the liq. sensor, is so covered, at least within the area defined by the window of (III), that a contact of the soln. can be effected only with the Au layer of (II), whereas a contact of the soln. with the Ni or Ni/Cr layer of (II) is prevented. ADVANTAGE - New circuit is simple to produce and easy to handle.