Transistor and display device

A transistor comprising:

• a gate electrode layer;
• a gate insulating layer over the gate electrode layer;
• an oxide semiconductor layer over the gate insulating layer;
• an oxide conductive layer over the oxide semiconductor layer;
• a source electrode layer over the oxide conductive layer;
• and
• a drain electrode layer over the oxide conductive layer;
• wherein the oxide conductive layer includes a microcrystalline region, and
• wherein a peak of a desorption constituent, which is derived from moisture, is not shown in a spectrum of the oxide semiconductor layer, which is shown with thermal desorption spectroscopy in a temperature range of greater than or equal to 200° C. and less than or equal to 350° C.

A display device comprising:

• a pixel portion over a substrate;
• and
• a driver circuit over the substrate and comprising a transistor;
• the transistor comprising:
• a gate electrode layer;
• a gate insulating layer over the gate electrode layer;
• an oxide semiconductor layer over the gate insulating layer;
• an oxide conductive layer over the oxide semiconductor layer;
• a source electrode layer over the oxide conductive layer;
• and
• a drain electrode layer over the oxide conductive layer;
• wherein the oxide conductive layer includes a microcrystalline region, and
• wherein a peak of a desorption constituent, which is derived from moisture, is not shown in a spectrum of the oxide semiconductor layer, which is shown with thermal desorption spectroscopy in a temperature range of greater than or equal to 200° C. and less than or equal to 350° C.