Semiconductor device and method for manufacturing the same

A semiconductor device comprising:

• a first transistor comprising a first semiconductor region;
• a second transistor comprising a first oxide semiconductor film;
• and
• a diode comprising a second semiconductor region and a second oxide semiconductor film,
• wherein the first semiconductor region and the second semiconductor region are formed on a same single crystal semiconductor substrate, and
• wherein the first oxide semiconductor film and the second oxide semiconductor film comprise the same oxide semiconductor.

A method for manufacturing a semiconductor device, comprising the steps of:

• forming a first semiconductor film and a second semiconductor film by processing a semiconductor layer;
• forming a first transistor comprising the first semiconductor film;
• forming an insulating layer to cover the first transistor and the second semiconductor film;
• exposing the second semiconductor film by removing a part of the insulating layer;
• forming an oxide semiconductor layer over the insulating layer and the second semiconductor film;
• forming a first oxide semiconductor film over the insulating layer and a second oxide semiconductor film over the second semiconductor film by processing the oxide semiconductor layer;
• and
• forming a second transistor comprising the first oxide semiconductor film and a diode comprising the second semiconductor film and the second oxide semiconductor film.