Formation of a two-layer via structure to mitigate damage to a display device

Patent metadata

Field	Value
Publication number	US-2021111366-A1
Application number	US-201916601712-A
Country	US
Kind code	A1
Filing date	Oct 15, 2019
Priority date	Oct 15, 2019
Publication date	Apr 15, 2021
Grant date	—

Abstract

In some embodiments, the present disclosure relates to a display device that includes an isolation structure disposed over a reflector electrode, a transparent electrode disposed over the isolation structure, an optical emitter structure disposed over the transparent electrode, and a via structure. The via structure extends from the transparent electrode at a top surface of the isolation structure to a top surface of the reflector electrode. The via structure includes a center horizontal segment that contacts the top surface of the reflector electrode, a sidewall vertical segment that contacts an inner sidewall of the isolation structure, and an upper horizontal segment that is connected to the center horizontal segment by the sidewall vertical segment. The upper horizontal segment is thicker than the center horizontal segment.

First claim

1 . A display device comprising:
an isolation structure disposed over a reflector electrode; a transparent electrode disposed over the isolation structure; an optical emitter structure disposed over the transparent electrode; and a via structure extending from the transparent electrode at a top surface of the isolation structure to a top surface of the reflector electrode, wherein the via structure comprises a center horizontal segment contacting the top surface of the reflector electrode, a sidewall vertical segment contacting an inner sidewall of the isolation structure, and an upper horizontal segment contacting the top surface of the isolation structure, wherein the upper horizontal segment is connected to the center horizontal segment by the sidewall vertical segment, and wherein the upper horizontal segment is thicker than the center horizontal segment.

2 . The display device of claim 1 , wherein the transparent electrode has a protrusion protruding into the via structure to the center horizontal segment, and wherein the via structure cups an underside of the protrusion.

3 . The display device of claim 1 , wherein the upper horizontal segment of the via structure comprises a conductive layer over a protective layer.

4 . The display device of claim 1 , wherein the via structure comprises titanium nitride.

5 . The display device of claim 1 , wherein the sidewall vertical segment and the center horizontal segment comprise a continuous layer of a single material.

6 . The display device of claim 1 , wherein a first thickness of each of the upper horizontal segment is measured in a first direction normal to the top surface of the reflector electrode, and wherein a second thickness of the center horizontal segment is measured in the first direction.

7 . The display device of claim 6 , wherein the sidewall vertical segment has a third thickness measured in a second direction that is perpendicular to the first direction, and wherein the first thickness is greater than the third thickness.

8 . A display device comprising:
a reflector electrode coupled to an interconnect structure; an isolation structure disposed over the reflector electrode; a transparent electrode disposed over the isolation structure; an optical emitter structure disposed over the transparent electrode; and a via structure extending from a top surface of the isolation structure to the reflector electrode, wherein the via structure comprises a first layer on the top surface of the isolation structure and further comprises a second layer, wherein the second layer overhangs the top surface of the isolation structure and is spaced from the top surface of the isolation structure by the first layer, and wherein the second layer has a downward protrusion directly contacting the reflector electrode and an inner sidewall of the isolation structure.

9 . The display device of claim 8 , wherein the top surface of the isolation structure has a first portion that directly contacts the via structure and a second portion that directly contacts the transparent electrode, wherein the first portion of the top surface of the isolation structure has a first average surface roughness, wherein the second portion of the top surface of the isolation structure has a second average surface roughness, wherein the first average surface roughness is about equal to the second average surface roughness.

10 . The display device of claim 8 , wherein the first layer comprises a different material than the second layer.

11 . The display device of claim 8 , wherein the via structure has a first thickness measured from the top surface of the isolation structure to a topmost surface of the via structure, wherein the via structure has a second thickness measured from a bottommost surface of the via structure to the bottommost surface of the transparent electrode, and wherein the first thickness is greater than the second thickness.

12 . The display device of claim 11 , wherein the via structure directly contacts an inner sidewall of the transparent electrode, wherein the via structure directly separates the inner sidewall of the isolation structure and the inner sidewall of the transparent electrode, wherein the via structure has a third thickness measured from the inner sidewall of the transparent electrode to the inner sidewall of the isolation structure, and wherein the first thickness is greater than the third thickness, and wherein the third thickness is about equal to the second thickness.

13 . The display device of claim 11 , wherein the first thickness is at least about 100 angstroms greater than the second thickness.

14 - 20 . (canceled)

21 . A display device comprising:
a first pixel region arranged over a substrate and comprising:
a first isolation structure disposed over a first reflector electrode,
a first transparent electrode disposed over the first isolation structure,
a first optical emitter structure disposed over the first transparent electrode, and
a first via structure extending from a topmost surface of the first isolation structure to the first reflector electrode, wherein the first via structure comprises a first layer on the topmost surface of the first isolation structure and a second layer arranged over the first layer, and wherein the second layer has a downward protrusion directly contacting the first reflector electrode and an inner sidewall of the first isolation structure; and
a second pixel region arranged over the substrate, laterally beside the first pixel region, and comprising:
a second isolation structure disposed over a second reflector electrode,
a second transparent electrode disposed over the second isolation structure,
a second optical emitter structure disposed over the second transparent electrode, and
a second via structure extending from a topmost surface of the second isolation structure to the second reflector electrode, wherein the second via structure comprises a third layer on the topmost surface of the isolation structure and a fourth layer arranged over the third layer, and wherein the fourth layer has a downward protrusion directly contacting the second reflector electrode and an inner sidewall of the second isolation structure.

22 . The display device of claim 21 , wherein the first and third layers of the first and second via structures, respectively, comprise a dielectric material, and wherein the second and fourth layers of the first and second via structures, respectively, comprise a conductive material.

23 . The display device of claim 21 , wherein the first and third layers of the first and second via structures, respectively, comprise a first conductive material, and wherein the second and fourth layers of the first and second via structures, respectively, comprise a second conductive material different than the first conductive material.

24 . The display device of claim 21 , further comprising:
a barrier structure arranged over the first isolation structure and the second isolation structure and arranged directly between the first optical emitter structure and the second optical emitter structure, wherein the first isolation structure directly contacts the second isolation structure.

25 . The display device of claim 21 , wherein a bottommost surface of the first transparent electrode is arranged below a topmost surface of the first isolation structure, and wherein a bottommost surface of the second transparent electrode is arranged below a topmost surface of the second isolation structure.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Chang Yung-Chang
• Liu Ming Chyi

Classifications

• H10K59/878

  comprising reflective means · CPC title

• H10K59/876

  comprising a resonant cavity structure, e.g. Bragg reflector pair · CPC title

• H10K59/80516

  combined with auxiliary electrodes, e.g. ITO layer combined with metal lines · CPC title

• H10K50/818

  Reflective anodes, e.g. ITO combined with thick metallic layers · CPC title

• H10K59/122 Primary

  Pixel-defining structures or layers, e.g. banks · CPC title