Low-conductivity micro-sensor and method for applying same

The invention discloses a low-conductivity micro-sensor and a method for applying the same. The low-conductivity micro-sensor comprises a substrate, a circular current electrode, annular voltage electrodes, an annular grounding electrode and electrode bonding pads. The current electrode, the voltage electrodes and the grounding electrode are sequentially concentrically arranged on the same surfaceof the substrate from the inside to the outside; the electrode bonding pads are positioned on the surface, which is opposite to the electrodes, of the substrate and is connected with the various electrodes by lead wires, the voltage electrodes comprise six concentric circular rings with equal widths, the concentric circular rings are equidistantly distributed and are sequentially a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode and a sixth electrode from the inside to the outside, the first voltage electrode comprises the first electrode, the third electrode and the fifth electrode, and the second voltage electrode comprises the second electrode, the fourth electrode and the sixth electrode. The method includes that the annular grounding electrode is used for shielding external electromagnetic interference when the low-conductivity micro-sensor is used, excitation current signals are applied to the circular current electrode, voltages between the two voltage electrodes are measured, and the conductivity of liquid can be obtained by means of computing. The low-conductivity micro-sensor and the method have the advantages that influenceon measurement results due to water flow directions can be prevented by the circular and annular electrodes, the electrodes and the to-be-measured liquid have large contact areas, and accordingly themeasurement precision can be improved.