EVALUATION METHOD FOR OXIDE SEMICONDUCTOR THIN FILM, QUALITY CONTROL METHOD FOR OXIDE SEMICONDUCTOR THIN FILM, AND EVALUATION ELEMENT AND EVALUATION DEVICE USED IN SAID EVALUATION METHOD

摘要

Provided are: a method for measuring and evaluating (predicting or estimating) the stress resistance of an oxide semiconductor thin film in a contactless manner accurately and easily; and a quality control method for an oxide semiconductor. This evaluation method for an oxide semiconductor thin film comprises a first step and a second step. The first step includes: subjecting a specimen on which an oxide semiconductor thin film has been formed to irradiation with both exciting light and microwave radiation; stopping the irradiation with the exciting light after the maximum intensity of the reflected wave of the microwave radiation from the oxide semiconductor thin film has been observed, the intensity of the reflected wave varying with the irradiation with the exciting light; and thereafter measuring a variation in the reflectance with which the microwave radiation is reflected by the oxide semiconductor thin film after the stopping. The second step includes: calculating, from the variation in the reflectance, a parameter that corresponds to slow attenuation found about 1μs after the stopping; and thus evaluating the stress resistance of the oxide semiconductor thin film.