Method for detecting gas with the use of photocurrent amplification and the like and gas sensor

摘要

An indium electrode film (2) is formed closely adhering to one face of an organic semiconductor film (1) made of copper phthalocyanine while a gold electrode film (3) is formed on the other face. A voltage is applied to the organic semiconductor film (1) so that the indium electrode (2) side is biased positively. By applying a voltage so that the electrode (2) side is charged positively and irradiating with a light having a wavelength absorbable by the organic semiconductor film (1) the phenomenon of photocurrent multiplication arises at the interface of the organic semiconductor film (1) and the electrode (2). When put under an oxygen or moisture atmosphere in the above state, this gas sensor can detect oxygen or moisture depending on a change in photocurrent due to the multiplication.