Thin film transistor, manufacturing method of same, and display device

A manufacturing method for a thin film transistor, comprising:

• processing including:
• forming a semiconductor layer made of an oxide having indium for a main component on a gate electrode on a substrate via a gate insulating layer, forming a first insulating film on a top face except a source electrode contact region and a drain electrode contact region of the semiconductor layer, and forming a second insulating film covering at least a pair of side surfaces of the semiconductor layer under a condition different from a condition for the first insulating film;
• or
• forming a semiconductor layer made of an oxide having indium for a main component on a substrate, forming a first insulating film on a top face except a source electrode contact region and a drain electrode contact region of the semiconductor layer, forming a second insulating film covering at least a pair of side surfaces of the semiconductor layer under a condition different from a condition for the first insulating film, and forming a gate electrode on the second insulating film;
• forming a source electrode on the source electrode contact region of the semiconductor layer;
• and
• forming a drain electrode on the drain electrode contact region of the semiconductor layer so as to face the source electrode to sandwich a part of the side surfaces of the semiconductor layer.

A display device comprising:

• a thin film transistor including:
• a substrate;
• a semiconductor layer provided on the substrate, the semiconductor layer being made of an oxide having indium for a main component, the semiconductor layer having a top face facing the substrate and a pair of side face, the top face having a first region, a second region, and an other region except the first region and the second region;
• a first insulating film covering the other region of the semiconductor layer;
• a second insulating film covering at least the pair of side surfaces of the semiconductor layer, the second insulating film being formed under a condition different from a condition for the first insulating film;
• a gate electrode provided on the first insulating film and the second insulating film or below the semiconductor layer;
• a source electrode provided on the first region;
• and
• a drain electrode provided on the second region, the drain electrode facing the source electrode, the drain electrode and the source electrode sandwiching the pair of the side surfaces of the semiconductor layer;
• and
• a display layer configured to cause at least one of optical emission and a change in an optical property including at least one of birefringence, optical activity, scattering property, diffraction property, and optical absorption, according to at least one of a voltage and a current supplied through the thin film transistor.