Semiconductor device and method for manufacturing same

A method for manufacturing a semiconductor device including a thin film transistor, the method comprising:

• step (A) of preparing a substrate that includes, formed on a surface thereof, a gate electrode and a gate insulating layer covering the gate electrode;
• step (B) of forming a semiconductor film made of amorphous silicon on the gate insulating layer;
• crystallization step (C) of crystallizing by irradiating only a portion of a semiconductor layer formation region of the semiconductor film to be a semiconductor layer with laser light, thereby forming a crystalline silicon region in the portion of the semiconductor layer formation region, where a portion of the semiconductor layer formation region that is not irradiated with laser light becomes a non-crystalline silicon region, wherein at least a portion of the crystalline silicon region is arranged in a portion of the semiconductor layer formation region that is to be a channel region;
• step (D) of forming a protection film on the semiconductor film, wherein the step (D) is performed between the step (B) and the step (C) or after the step (C);
• step (E) of patterning the protection film so as to form a protection layer that covers at least a part of the portion to be the channel region and has a first opening or a first notch that exposes the semiconductor film;
• step (F) of forming a contact layer silicon film and a source and drain electrode conductive film in this order on the protection layer;
• and
• patterning step (G) of patterning the source and drain electrode conductive film and the contact layer silicon film using a first mask so as to form a source electrode and a drain electrode separated from each other and a first contact layer and a second contact layer separated from each other, and patterning the semiconductor film using the first mask and the protection layer as a mask so as to form the semiconductor layer, wherein the semiconductor layer has a second opening or a second notch that exposes the gate insulating layer at positions corresponding to the first opening and the first notch of the protection layer.

A method for manufacturing a semiconductor device including a thin film transistor, the method comprising:

• step (A) of preparing a substrate that includes, formed on a surface thereof, a gate electrode and a gate insulating layer covering the gate electrode;
• step (B) of forming a semiconductor film made of amorphous silicon on the gate insulating layer;
• crystallization step (C) of crystallizing by irradiating at least a portion of a semiconductor layer formation region of the semiconductor film to be a semiconductor layer with laser light, thereby forming a crystalline silicon region in the portion of the semiconductor layer formation region, where a portion of the semiconductor film that is not irradiated with laser light becomes a non-crystalline silicon region, wherein at least a portion of the crystalline silicon region is arranged in a portion of the semiconductor layer formation region that is to be a channel region;
• step (D) of forming a protection film on the semiconductor film, wherein the step (D) is performed between the step (B) and the step (C) or after the step (C);
• step (E) of patterning the protection film and the semiconductor film so as to form a protection layer and a semiconductor layer, wherein the semiconductor layer and the protection layer have an opening or a notch that exposes the gate insulating layer;
• step (F) of forming a contact layer silicon film and a source and drain electrode conductive film in this order so as to cover the protection layer and the semiconductor layer;
• and
• patterning step (G) of patterning the source and drain electrode conductive film and the contact layer silicon film using a first mask so as to form a source electrode and a drain electrode separated from each other and a first contact layer and a second contact layer separated from each other, and removing portions of the source and drain electrode conductive film and the contact layer silicon film that are located in the opening or the notch.