Display device having vertical oxide semiconductor channel layer on sidewall of insulating spacer

1. A display device, comprising:

a substrate;

a first insulating layer having a first side wall and a top surface;

an oxide semiconductor layer on the first side wall and the top surface;

a gate electrode facing the oxide semiconductor layer;

a gate insulating layer between the oxide semiconductor layer and the gate electrode;

a transparent conductive layer between the oxide semiconductor layer and the substrate, the transparent conductive layer being connected with a first portion of the oxide semiconductor layer;

a first electrode on the top surface of the first insulating layer, the first electrode being connected with a second portion of the oxide semiconductor layer via an opening in the gate insulating layer;

a second electrode between the substrate and the oxide semiconductor layer, the second electrode being connected with the transparent conductive layer;

a gate line to be supplied with a gate voltage controlling a transistor including a channel formed of the oxide semiconductor layer to be on or off; and

a data line to be supplied with a data signal corresponding to a gray scale of a pixel including the transparent conductive layer;

wherein:

the gate line is connected with the gate electrode;

the data line is connected with the first electrode;

the transistor includes a crossing area of the gate line and the data line;

the first electrode is a source electrode of the transistor;

the second electrode is a drain electrode of the transistor; and

the transparent conductive layer and the first electrode on the top surface of the first insulating layer overlap.

2. The display device according to claim 1 , further comprising a third transparent conductive layer forming the same layer with the transparent conductive layer and a second transparent conductive layer, the third transparent conductive layer facing the second transparent conductive layer as seen in a plan view and being electrically separated from the second transparent conductive layer.

3. The display device according to claim 1 , further comprising a third insulating layer between the gate electrode and the first electrode.

4. The display device according to claim 1 , further comprising a third electrode between the top surface of the first insulating layer and the oxide semiconductor layer.

5. The display device according to claim 4 , wherein the first side wall has a tapered inclining surface tending to close upward.

6. The display device according to claim 5 , wherein the first side wall is ring-shaped as seen in a plan view.

7. The display device according to claim 6 , wherein the first electrode is connected with the oxide semiconductor layer via the third electrode.