# US 9,519,190 B2 · Display device and manufacturing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,519,190 B2 - Document ID: US9519190B2 - Status: Granted - Kind: B2 - Application number: 14/264,248 - Filed: 2014-04-29 - Published: 2015-01-15 - Granted: 2016-12-13 - Earliest claimed: 2013-07-10 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Kyung Tae Chae; Seon Uk Lee; Chung Hyuk Lee; Tae Woo Lim; Don Chan Cho - Web page: https://patentgrep.com/patent/US9519190B2 ## CPC - G02F 1/1341: Filling or closing of cells - G02F 1/133345: {Insulating layers (G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence)} - G02F 1/133377: {Cells with plural compartments or having plurality of liquid crystal microcells partitioned by walls, e.g. one microcell per pixel} - G02F 1/1335: Structural association of cells with optical devices, e.g. polarisers or reflectors - G02F 1/133514: {Colour filters} - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract A display device includes a substrate including a plurality of pixel areas, a thin film transistor positioned on the substrate, a first insulating layer positioned on the thin film transistor, a pixel electrode connected with the thin film transistor and positioned on the first insulating layer, a common electrode positioned on the pixel electrode and spaced apart from the pixel electrode by a microcavity, a second insulating layer positioned on the common electrode, a roof layer positioned on the second insulating layer, a thickness of the roof layer being about 4 μm to about 50 μm, an injection hole through the common electrode, the second insulating layer, and the roof layer, the injection hole exposing a part of the microcavity, a liquid crystal layer filling the microcavity, and an overcoat on the roof layer and extending into the injection hole, the overcoat sealing the microcavity. ## Claims ### Claim 1 A display device, comprising: a substrate including a plurality of pixel areas; a thin film transistor positioned on the substrate; a first insulating layer positioned on the thin film transistor; a pixel electrode connected with the thin film transistor and positioned on the first insulating layer; a color filter positioned between the substrate and the pixel electrode; a common electrode positioned on the pixel electrode and spaced apart from the pixel electrode by a microcavity; a second insulating layer positioned on the common electrode; a roof layer positioned on the second insulating layer, a thickness of the roof layer being about 4 μm to about 50 μm; an injection hole through the common electrode, the second insulating layer, and the roof layer, the injection hole exposing a part of the microcavity; a liquid crystal layer filling the microcavity; an overcoat positioned on the roof layer and extending into the injection hole, the overcoat sealing the microcavity; and a third insulating layer positioned between the overcoat and the roof layer. ### Claim 2 (depends on 1) The display device as claimed in claim 1, wherein the thickness of the roof layer is about 8 μm to about 50 μm. ### Claim 3 (depends on 2) The display device as claimed in claim 2, wherein an angle between the roof layer and the second insulating layer is about 45°. ### Claim 4 (depends on 1) The display device as claimed in claim 1, wherein an angle between the roof layer and the second insulating layer is about 30° to about 90°. ### Claim 5 (depends on 4) The display device as claimed in claim 4, wherein the angle between the roof layer and the second insulating layer is about 45°. ### Claim 6 (depends on 4) The display device as claimed in claim 4, wherein a tilted surface of the roof layer has a step shape. ### Claim 7 (depends on 1) The display device as claimed in claim 1, further comprising a water-repellent layer positioned on the roof layer. ### Claim 8 (depends on 1) The display device as claimed in claim 1, wherein the second insulating layer includes at least one of silicon nitride, silicon oxide, and silicon oxynitride. ### Claim 9 (depends on 1) The display device as claimed in claim 1, wherein the third insulating layer includes at least one of silicon nitride, silicon oxide, and silicon oxynitride. ### Claim 10 (depends on 1) The display device as claimed in claim 1, wherein the overcoat positioned in the injection hole defines a valley between adjacent microcavities, a bottom of the valley being lower than a top of the microcavities. ### Claim 11 A manufacturing method of a display device, the method comprising: forming a thin film transistor on a substrate, the substrate including a plurality of pixel areas; forming a first insulating layer on the thin film transistor; forming a pixel electrode connected with the thin film transistor on the first insulating layer; forming a color filter between the substrate and the pixel electrode; forming a sacrificial layer on the pixel electrode; forming a common electrode on the sacrificial layer; forming a second insulating layer on the common electrode; forming a roof layer by applying and patterning an organic material onto the second insulating layer, a thickness of the roof layer being about 4 μm to about 50 μm; exposing the sacrificial layer; forming a microcavity between the pixel electrode and the common electrode by removing the exposed sacrificial layer; forming an injection hole through the common electrode, the second insulating layer, and the roof layer, the injection hole exposing a part of the microcavity; forming a liquid crystal layer by injecting a liquid crystal material into the microcavity; forming an overcoat on the roof layer and in the injection hole, such that the overcoat seals the microcavity; and forming a third insulating layer between the overcoat and the roof layer. ### Claim 12 (depends on 11) The method as claimed in claim 11, wherein the thickness of the roof layer is about 8 μm to about 50 μm. ### Claim 13 (depends on 11) The method as claimed in claim 11, wherein an angle between the roof layer and the second insulating layer is about 30° to about 90°. ### Claim 14 (depends on 13) The method as claimed in claim 13, wherein the angle between the roof layer and the second insulating layer is about 45°. ### Claim 15 (depends on 13) The method as claimed in claim 13, wherein a tilted surface of the roof layer has a step shape. ### Claim 16 (depends on 11) The method as claimed in claim 11, further comprising forming a water-repellent layer on the formed roof layer. ### Claim 17 (depends on 16) The method as claimed in claim 16, further comprising removing the third insulating layer formed directly on the sacrificial layer by patterning the third insulating layer. ### Claim 18 (depends on 17) The method as claimed in claim 17, wherein the sacrificial layer is ashed, and thereafter, the third insulating layer is formed. ### Claim 19 (depends on 18) The method as claimed in claim 18, wherein during ashing of the sacrificial layer, the third insulating layer positioned directly on the sacrificial layer is lifted off.