A pH sensor is provided capable of readily determining the pH of a solution of a small amount. The pH sensor includes a semiconductor substrate, an oxide film provided on the semiconductor substrate, a solution storage part for holding a solution on the oxide film, and an electrode to be in contact with...http://www.google.com/patents/US6464940?utm_source=gb-gplus-sharePatent US6464940 - pH sensor and pH measurement method employing the same
