Display device including polycrystalline silicon layer, method of manufacturing polycrystalline silicon layer, and method of manufacturing display device

Patent metadata

Field	Value
Publication number	US-11942481-B2
Application number	US-202117510995-A
Country	US
Kind code	B2
Filing date	Oct 26, 2021
Priority date	Mar 19, 2019
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

A display device may include a thin film transistor disposed on a substrate, and a display element electrically connected to the thin film transistor. The thin film transistor may include an active pattern including polycrystalline silicon, a gate insulation layer disposed on the active pattern, and a gate electrode disposed on the gate insulation layer. An average value of grain sizes of the active pattern may be in a range of about 400 nm to about 800 nm. An RMS value of a surface roughness of the active pattern may be about 4 nm or less. A method of manufacturing a polycrystalline silicon layer may include cleaning an amorphous silicon layer with hydrofluoric acid, rinsing the amorphous silicon layer with hydrogenated deionized water, and irradiating the amorphous silicon layer with a laser beam having an energy density of about 440 mJ/cm 2 to about 490 mJ/cm 2 .

First claim

What is claimed is:

1. A method of manufacturing a polycrystalline silicon layer, comprising:
forming an amorphous silicon layer on a substrate;
cleaning the amorphous silicon layer with hydrofluoric acid;
rinsing the amorphous silicon layer with hydrogenated deionized water; and
irradiating the amorphous silicon layer with a laser beam having an energy density in a range of about 440 mJ/cm 2 to about 490 mJ/cm 2 to form the polycrystalline silicon layer.

2. The method of claim 1 , wherein a thickness of the amorphous silicon layer is in a range of about 370 Å to about 500 Å.

3. The method of claim 1 , wherein the hydrofluoric acid includes a hydrogen fluoride in an amount of about 0.5%.

4. The method of claim 1 wherein the cleaning the amorphous silicon layer is performed for a time period of about 60 seconds to about 120 seconds.

5. The method of claim 1 , wherein a hydrogen concentration of the hydrogenated deionized water is about 1.0 ppm.

6. The method of claim 1 , wherein a wavelength of the laser beam is about 308 nm.

7. The method of claim 1 , wherein a scan pitch of the laser beam is about 10 μm or less.

8. The method of claim 1 , wherein the forming the polycrystalline silicon layer includes forming grains in the polycrystalline silicon layer, an average size of the grains of the polycrystalline silicon layer is in a range of about 400 nm to about 800 nm.

9. The method of claim 1 , wherein the forming the polycrystalline silicon layer includes forming a rough surface of the polycrystalline silicon layer, a root-mean-square value of a roughness of the rough surface of the polycrystalline silicon layer is about 4 nm or less.

10. A method of manufacturing a display device, comprising:
forming an amorphous silicon layer on a substrate;
cleaning the amorphous silicon layer with hydrofluoric acid;
rinsing the amorphous silicon layer with hydrogenated deionized water;
irradiating the amorphous silicon layer with a laser beam having an energy density in a range of about 440 mJ/cm 2 to about 490 mJ/cm 2 to form a polycrystalline silicon layer;
etching the polycrystalline silicon layer to form a polycrystalline silicon pattern;
forming an insulation layer on the polycrystalline silicon pattern;
forming a gate electrode on the insulation layer;
injecting an ion at a portion of the polycrystalline silicon pattern to form an active pattern; and
forming a display element on the gate electrode.

11. The method of claim 10 , wherein a scan pitch of the laser beam is about 10 μm or less.

12. The method of claim 10 , wherein the forming the display element comprises:
forming a first electrode on the gate electrode, the first electrode being electrically connected to the active pattern;
forming an emission layer on the first electrode; and
forming a second electrode on the emission layer.

Assignees

• Samsung Display Co Ltd

Inventors

• Lee Dong-Sung
• Seo Jongoh
• So Byung Soo
• Lee Dong-Min
• Jeon Yeon Hee
• Choi Jonghoon

Classifications

• H10P14/3808

  using laser beams · CPC title

• H10P14/3454

  Amorphous · CPC title

• H10P14/3816

  Pulsed laser beam · CPC title

• H10P14/3411

  Silicon, silicon germanium or germanium · CPC title

• H10P14/3456

  Polycrystalline · CPC title