Quality evaluation method of target assembly used in forming thin film for semiconductor layers of thin film transistor

Abstract

The invention provides a quality evaluation method of a target assembly used in forming a thin film for semiconductor layers of a thin film transistor, which can simply evaluate the quality of the target assembly. The evaluation method includes a first step of preparing the target assembly which is formed by arranging a plurality of oxide target members by means of the slits of bonding materials on a back board, a second step of forming a thin film by sputtering on the target assembly, a third step of irradiating exciting-light and microwave on the area, including the seaming part corresponding to the slit of the target assembly, of the thin film, stopping the irradiation of exciting-light after the maximum value, varying based on the irradiation of the exciting-light, of the reflective wave from the seaming part of the microwave is measured, measuring the variation of the reflection rate of the reflective wave from the seaming part of the microwave after the irradiation of the exciting-light is stopped, and calculating out the life expectancy value Tau1 of the seaming part of the thin film when the reflection rate becomes 1 / e, and a fourth step of evaluating the quality of the target assembly based on the life expectancy value Tau1 of the seaming part.

Description

technical field [0001] The present invention relates to a method of evaluating the quality of a target assembly used for forming a thin film for a semiconductor layer of a thin film transistor (TFT). Specifically, when evaluating the quality of the above-mentioned target assembly (whether the quality of a thin film useful as a semiconductor layer of a TFT can be formed using the target assembly), even if the sputtering target is not actually used, the sputtering method The characteristics (mobility, TFT characteristics) of thin films are specially evaluated as TFTs provided in semiconductor layers, and the quality of target assemblies can be easily and accurately evaluated by measuring the lifetime of the thin films by the microwave photoconductivity attenuation method. Background technique [0002] Amorphous (amorphous) thin films used as semiconductor layers of TFTs, in addition to general-purpose amorphous silicon (a-Si), recently used, for example, include indium (In), g...

AI Technical Summary

Problems solved by technology

[0014] In the past, when determining the degradation of TFT characteristics caused by the gap portion during the manufacture of such a target assembly, it was impossible to evaluate the TFT without actually using the target assembly to form a semiconductor thin film and attaching electrodes to the semiconductor thin film. If it is judged to be defective after TFT, it is necessary to recreate the target assembly from the beginning, resulting in a significant reduction in productivity and cost

Images