Semiconductor device and display device

A semiconductor device comprising:

• a substrate;
• and
• an optical sensor unit on said substrate for sensing light and generating a sensing signal, said optical sensor unit including a first thin film diode having an amorphous semiconductor layer, and a second thin film diode having a crystalline semiconductor layer,
• wherein said first thin film diode and said second thin film diode are connected in parallel, and
• wherein said sensing signal is generated based on output of one of said first thin film diode and said second thin film diode.

A method for manufacturing a semiconductor device comprising a substrate, an optical sensor unit formed on said substrate that includes a first thin film diode and a second thin film diode, and a thin film transistor formed on said substrate, the method comprising:

• (a) forming an amorphous semiconductor film on said substrate;
• (b) from said amorphous semiconductor film, forming a second island-shape semiconductor layer that becomes an active region of said second thin film diode, and a third island-shape semiconductor layer that becomes an active region of said thin film transistor;
• and
• (c) forming on said substrate a first island-shape semiconductor layer that becomes an active region of said first thin film diode,
• wherein the bandgap of said first island-shape semiconductor layer is larger than the bandgap of said second island-shape semiconductor layer,
• wherein said step (b) and said step (c) include:
• crystallizing a part of said amorphous semiconductor film to form a semiconductor film including a crystalline region and an amorphous region;
• and
• patterning said semiconductor film to form said second and third island-shape semiconductor layers from said crystalline region, and to form said first island-shape semiconductor layer from said amorphous region.

A method for manufacturing a semiconductor device comprising a substrate, an optical sensor unit formed on said substrate that includes a first thin film diode and a second thin film diode, and a thin film transistor formed on said substrate, the method comprising:

• (a) forming an amorphous semiconductor film on said substrate;
• (b) from said amorphous semiconductor film, forming a second island-shape semiconductor layer that becomes an active region of said second thin film diode, and a third island-shape semiconductor layer that becomes an active region of said thin film transistor;
• and
• (c) forming on said substrate a first island-shape semiconductor layer that becomes an active region of said first thin film diode,
• wherein the bandgap of said first island-shape semiconductor layer is larger than the bandgap of said second island-shape semiconductor layer,
• wherein said step (b) includes:
• crystallizing said amorphous semiconductor film to form a crystalline semiconductor film;
• and
• patterning said crystalline semiconductor film to form said second and third island-shape semiconductor layers,
• wherein said step (c) is performed after said step (b), and
• wherein said first island-shape semiconductor layer is an amorphous semiconductor layer.