Solid state sensor for metal ion detection and trapping in solution

摘要

A device, apparatus and method for trapping metal ions and detecting metal ion contamination in a solution provide a semiconductor device formed on a semiconductor substrate and including an N-well formed over a P-type substrate and at least a contact portion of the N-well in electrical contact with the solution. When the semiconductor device is optically illuminated, a P/N junction is formed as a result of photovoltaic phenomena. Metal ions from the solution migrate to the contact area due to the voltage created at the P/N junction. The semiconductor device includes a conductive structure with conductive features separated by a gap and therefore in an initially electrically open state. When the ions migrate to the contact area, they precipitate, at least partially bridging the gap and creating conductance through the conductive structure. The conductance may be measured to determine the amount of metal ion contamination.

主权项

1. A method for detecting metal ions in a solution comprising:
providing a semiconductor device contacting a solution, said semiconductor device comprising at least one N-type material layer oriented in a first direction and covering a P-type material layer oriented in said first direction, and a dielectric layer disposed over said at least one N-type material layer and including an opening therethrouqh such that at least one contact part of said at least one N-type material layer directly contacts said solution; optically illuminating said semiconductor device thereby creating a voltage across a P/N junction and causing metal ions of said solution to migrate to said at least one contact part; monitoring conductance of a structure of said semiconductor device having a conductance that varies with an amount of said metal ions accumulated on said semiconductor device; and calculating a concentration of said metal ions in said solution, based on said conductance.