Instrument for polarographic potentiometric, thermal and like measurements and a method of making the same

摘要

A probe having a measuring device for polarographic, potentiometric, thermal and like measurements has a high-resistance transducer which is provided with leads. A body of insulating material is arranged about the transducer and a metal-containing body is arranged about the insulating material. The metal-containing body includes a metal layer which is essentially free of pores and essentially impervious to the diffusion of liquid therethrough and which thus seals the insulating material against contamination by foreign matter. A metal layer which is essentially free of pores and essentially impervious to the diffusion of liquid therethrough may be formed by sputtering the metal onto a substrate using a high-frequency field at an output of 10 to 40 watts per square centimeter of target surface, the sputtering operation being carried out for a period of 5 to 10 minutes in an Ar atmosphere having a pressure of 8 x10-4 torr. An insulating layer may be formed by sputtering an insulating material onto a substrate using a high-frequency field and an atmosphere made up of a protective gas and a reactive gas having partial pressures such that the total pressure of the atmosphere is 8 x10-4 torr.