OXIDE SEMICONDUCTOR, SEMICONDUCTOR DEVICE, SEMICONDUCTOR MEMORY DEVICE AND SOLID-STATE IMAGING DEVICE

PROBLEM TO BE SOLVED: To provide an oxide semiconductor improved in heat resistance, a semiconductor device, a semiconductor memory device and a solid-state imaging device.SOLUTION: An oxide semiconductor is provided according to an embodiment, which comprises indium (In), gallium (Ga) and silicon (Si). In the oxide semiconductor, the composition ratio (Si/In) of Si and In is larger than 0.2. In the oxide semiconductor, the composition ratio (Si/Ga) of Si and Ga is larger than 0.2.SELECTED DRAWING: Figure 1 【課題】耐熱性を向上させた酸化物半導体、半導体装置、半導体記憶装置及び固体撮像装置を提供する。【解決手段】実施形態によれば、インジウム（Ｉｎ）とガリウム（Ｇａ）とシリコン（Ｓｉ）とを含む酸化物半導体であって、前記酸化物半導体におけるＳｉとＩｎの組成比(Ｓｉ／Ｉｎ)は、０．２よりも大きく、前記酸化物半導体におけるＳｉとＧａの組成比(Ｓｉ／Ｇａ)は、０．２よりも大きい酸化物半導体が提供される。【選択図】図１