Semiconductor device

A semiconductor device comprising:

• a gate electrode;
• an oxide semiconductor film comprising a channel region;
• and
• a source electrode and a drain electrode,
• wherein the channel region is positioned between a first side surface of the source electrode and a second side surface of the drain electrode opposite to the first side surface,
• wherein the oxide semiconductor film comprises a side surface which overlaps with the gate electrode,
• wherein the side surface of the oxide semiconductor film comprises a first high resistance region positioned between a first region nearest to one end of the first side surface and a second region nearest to one end of the second side surface, and
• wherein the first high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

A semiconductor device comprising:

• a gate electrode;
• a gate insulating film over the gate electrode;
• an oxide semiconductor film over the gate insulating film, the oxide semiconductor film comprising a channel region;
• and
• a source electrode and a drain electrode each electrically connected to the oxide semiconductor film,
• wherein the channel region is positioned between a first side surface of the source electrode and a second side surface of the drain electrode opposite to the first side surface,
• wherein the oxide semiconductor film comprises a side surface which overlaps with the gate electrode,
• wherein the side surface of the oxide semiconductor film comprises a first high resistance region positioned between a first region nearest to one end of the first side surface and a second region nearest to one end of the second side surface, and
• wherein the first high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.