| 摘要 |
PROBLEM TO BE SOLVED: To provide an oxide semiconductor material capable of achieving the stability of a threshold voltage (Vth) [a threshold voltage shift amount &Dgr;Vth is ±3 V or less, at PBS (Positive Bias Stress) and NBIS (Negative Bias Irradiation Stress)] and the mobility of 5 cm/Vs or more required for an operation of an OLED display device without causing a problem of a small selection ratio that makes achievement of a channel etching structure difficult and a problem at formation of a protection film that oxygen deficiency is generated in a film, and to provide a sputtering target using the oxide material, a protection film for a TFT, and an oxide semiconductor device using them.SOLUTION: There is provided an oxide semiconductor target obtained by sintering an oxide semiconductor material obtained by adding any one or two kinds of W, Ta and Hf of 5d transition metal oxides to a semiconductor material containing Zn-Sn-O as a main component by respective ranges of 0.07-3.8 atom%, 0.5-4.7 atom%, and 0.32-6.4 atom%. Also, there is provided a semiconductor channel layer and an oxide semiconductor material for a TFT protection film formed by using the target, and a semiconductor device having them. |
