摘要 |
A semiconductor device using an oxide semiconductor, with stable electric characteristics and high reliability. In a process for manufacturing a bottom-gate transistor including an oxide semiconductor film, dehydration or dehydrogenation is performed by heat treatment and oxygen doping treatment is performed. The transistor including the oxide semiconductor film subjected to the dehydration or dehydrogenation by the heat treatment and the oxygen doping treatment is a transistor having high reliability in which the amount of change in threshold voltage of the transistor by the bias-temperature stress test (BT test) can be reduced. |