Manufacturing method of semiconductor device

A method for manufacturing a semiconductor device comprising:

• forming a semiconductor layer over a substrate;
• forming a first insulating layer over the semiconductor layer;
• forming a first conductive layer over the first insulating layer;
• forming a second conductive layer over and in contact with the first conductive layer;
• adding an impurity into the semiconductor layer to form a non-impurity added region at one end of the semiconductor layer, a first impurity region, and a second impurity region at the other end of the semiconductor layer;
• and
• forming a second insulating layer over the second conductive layer and in direct contact with a portion of a top surface of the first conductive layer,
• wherein a width of the first impurity region is larger than a width of the non-impurity added region, and
• wherein a width of the first conductive layer is larger than a width of the second conductive layer.

A method for manufacturing a semiconductor device comprising:

• forming a semiconductor layer over a substrate;
• forming a first insulating layer over the semiconductor layer;
• forming a first conductive layer over the first insulating layer;
• forming a second conductive layer over and in contact with the first conductive layer;
• adding an impurity into the semiconductor layer to form a non-impurity added region at one end of the semiconductor layer, a first impurity region, and a second impurity region at the other end of the semiconductor layer;
• and
• forming second insulating layer over the second conductive layer and in direct contact with a portion of a top surface of the first conductive layer,
• wherein a width of the first impurity region is larger than a width of the second impurity region, and
• wherein a width of the first conductive layer is larger than a width of the second conductive layer.