Photodetector, display substrate including photodetector, method of fabricating photodetector, and display panel

1. A display substrate, comprising

a base substrate, a photodetector on the base substrate, and a pixel unit on the base substrate, wherein

the pixel unit includes a light-emitting device configured to emit light, and the photodetector includes a first electrode, a second electrode, a light-sensitive layer, and a light-trapping layer;

the light-sensitive layer is between the first electrode and the second electrode, and the light-trapping layer is between the light-sensitive layer and the base substrate;

the display substrate further includes a first barrier layer, the first barrier layer covers a top surface of the light-sensitive layer and a portion of a side surface of the light-sensitive layer, and the first barrier layer is configured to prevent ions in other layers of the display substrate from contaminating the light-sensitive layer.

2. The display substrate according to claim 1 ,

wherein the pixel unit further comprises a first switch between the base substrate and the light-emitting device, and the photodetector further comprises a second switch between the base substrate and the first electrode, and

wherein the first electrode is coupled to the second switch.

3. The display substrate according to claim 2 ,

wherein the light-emitting device comprises a third electrode, a light-emitting layer, and a fourth electrode arranged in a stack, the fourth electrode being farther from the base substrate than the third electrode and the light-emitting layer, and

wherein the third electrode is coupled to the first switch.

4. The display substrate according to claim 3 ,

wherein the third electrode is a reflective electrode, and the fourth electrode is a transparent electrode, and

wherein an orthographic projection of the light-sensitive layer on the base substrate is entirely outside an orthographic projection of the third electrode on the base substrate.

5. The display substrate according to claim 4 ,

wherein the third electrode comprises at least one sub-electrode layer composed of a transparent conductive material, and a reflective layer composed of a metallic material selected from the group consisting of silver, aluminum, copper, and an alloy thereof.

6. The display substrate according to claim 3 ,

wherein the third electrode is a transparent electrode, and the fourth electrode is a reflective electrode, and

wherein an orthographic projection of the light-sensitive layer on the base substrate at least partially overlaps with an orthographic projection of the third electrode on the base substrate.

7. The display substrate according to claim 6 , wherein the fourth electrode is composed of a metallic material selected from the group consisting of lithium, magnesium, calcium, barium, aluminum, indium, and an alloy thereof.

8. A display panel comprising the display substrate according to claim 1 .

9. The display substrate according to claim 1 , wherein the display substrate further includes a first capacitor, the first electrode is one electrode of the first capacitor.

10. The display substrate according to claim 2 , wherein the display substrate further includes a second barrier layer, the first switch and the second switch are transistors, the first switch includes a first gate electrode, the second switch includes a second gate electrode, and the second barrier layer includes the first gate electrode and the second gate electrode;

the first switch and the second switch are disposed between the second barrier layer and the base substrate;

an orthographic projection of the first gate electrode on the base substrate covers an orthographic projection of the first switch on the base substrate; and

an orthographic projection of the second gate electrode on the base substrate covers an orthographic projection of the second switch on the base substrate.