Semiconductor device and method of fabricating the same

• US 9,069,215 B2
• Filed: 09/09/2009
• Issued: 06/30/2015
• Est. Priority Date: 07/06/1999
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Hirakata, Yoshiharu, Goto, Yuugo, Kobayashi, Yuko, Yamazaki, Shunpei
• Primary Examiner(s): Landau, Matthew
• Assistant Examiner(s): Anya, Igwe U
• Application Number:
  US12/556,135
• Publication Number:
  US 20090322698A1
• Time in Patent Office: 2,120 Days
• Field of Search: 257/72, 257/E27.111
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13306 Circuit arrangements or driving methods for the control of single liquid crystal cells G02F1/132, G02F1/133382 take precedence
• CPC Class Codes: G02F 1/133302 Rigid substrates, e.g. inorganic substrates
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 2029/7863 with an LDD consisting of more than one lightly doped zone or having a non-homogeneous dopant distribution, e.g. graded LDD
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1222 with a particular composition, shape or crystalline structure of the active layer
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1288 employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• CPC Class Codes: H01L 29/167 further characterised by the doping material H01L29/1604 takes precedence
• CPC Class Codes: H01L 29/78621 with LDD structure or an extension or an offset region or characterised by the doping profile
• CPC Class Codes: H01L 29/78627 with a significant overlap between the lightly doped drain and the gate electrode, e.g. GOLDD
• CPC Class Codes: H01L 29/78669 with inverted-type structure, e.g. with bottom gate
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10S 438/924 : To facilitate selective etching
• CPC Class Codes: Y10S 438/98 : Utilizing process equivalents or options

Abstract

There is provided a high quality liquid crystal panel having a thickness with high accuracy, which is designed, without using a particulate spacer, within a free range in accordance with characteristics of a used liquid crystal and a driving method, and is also provided a method of fabricating the same. The shape of a spacer for keeping a substrate interval constant is made such that it is a columnar shape, a radius R of curvature is 2 μm or less, a height H is 0.5 μm to 10 μm, a diameter is 20 μm or less, and an angle α is 65° to 115°. By doing so, it is possible to prevent the lowering of an opening rate and the lowering of light leakage due to orientation disturbance.

Claims

1. A display device comprising:

a first substrate;

a gate electrode over the first substrate;

a semiconductor layer overlapping with the gate electrode;

a first insulating layer disposed between the gate electrode and the semiconductor layer;

a first conductive layer over and electrically connected the semiconductor layer;

a second conductive layer over and electrically connected the semiconductor layer;

a second insulating layer over the gate electrode, the first conductive layer, and the second conductive layer;

a pixel electrode over the second insulating layer, the pixel electrode electrically connected to the first conductive layer;

a second substrate opposed to the first substrate;

a liquid crystal material disposed between the first substrate and the second substrate;

a first photolithographic spacer disposed between the first substrate and the second substrate; and

a second photolithographic spacer disposed between the first substrate and the second substrate,

wherein the first photolithographic spacer and the second photolithographic spacer are disposed in a region surrounded by a sealing region,

wherein each of the gate electrode, the first insulating layer, the semiconductor layer, the first conductive layer, and the pixel electrode overlaps with the first photolithographic spacer,

wherein each of the gate electrode, the semiconductor layer, the first conductive layer, the second conductive layer, and the pixel electrode does not overlap with the second photolithographic spacer, and

wherein the first photolithographic spacer has a cross-section in which a width of a second substrate side end portion of the first photolithographic spacer is larger than a width of a center portion of the first photolithographic spacer, and the width of the center portion of the first photolithographic spacer is larger than a width of a first substrate side end portion of the first photolithographic spacer.

2. The display device according to claim 1, wherein a sectional shape of the first photolithographic spacer in a radial direction is one selected from the group consisting of a circle, an ellipse, a triangle, a quadrilateral, and a polygon having sides more than four.

3. The display device according to claim 1, wherein the first photolithographic spacer is disposed between the pixel electrode and the second substrate.

4. The display device according to claim 1, further comprising:

a touch detection element overlapping with the liquid crystal material, wherein the touch detection element is any one of an optical detecting element, a pressure sensitive type detecting element, and a capacitive type detecting element.

5. The display device according to claim 4, further comprising:

an LED backlight overlapping with the liquid crystal material.

6. The display device according to claim 1, wherein the pixel electrode electrically connected to the first conductive layer so that a part of the pixel electrode is located in a contact hole of the second insulating layer.

7. The display device according to claim 1, further comprising:

an alignment film disposed between the pixel electrode and the first photolithographic spacer.

8. The display device according to claim 1, wherein the gate electrode is located under the semiconductor layer.

9. A display device comprising:

a first substrate;

a gate electrode over the first substrate;

a semiconductor layer overlapping with the gate electrode;

a first insulating layer disposed between the gate electrode and the semiconductor layer;

a first conductive layer over and electrically connected the semiconductor layer;

a second conductive layer over and electrically connected the semiconductor layer;

a second insulating layer over the gate electrode, the first conductive layer, and the second conductive layer;

a pixel electrode over the second insulating layer, the pixel electrode electrically connected to the first conductive layer;

a second substrate opposed to the first substrate;

a liquid crystal material disposed between the first substrate and the second substrate; and

a first spacer disposed between the first substrate and the second substrate, the first spacer comprising a photopolymerization type insulating film; and

a second spacer disposed between the first substrate and the second substrate, the second spacer comprising a photopolymerization type insulating film,

wherein the first spacer and the second spacer are disposed in a region surrounded by a sealing region,

wherein each of the gate electrode, the first insulating layer, the semiconductor layer, the first conductive layer, and the pixel electrode overlaps with the first spacer,

wherein each of the gate electrode, the semiconductor layer, the first conductive layer, the second conductive layer, and the pixel electrode does not overlap with the second spacer, and

wherein the first spacer has a cross-section in which a width of a second substrate side end portion of the first spacer is larger than a width of a center portion of the first spacer, and the width of the center portion of the first spacer is larger than a width of a first substrate side end portion of the first spacer.

10. The display device according to claim 9, wherein a sectional shape of the first spacer in a radial direction is one selected from the group consisting of a circle, an ellipse, a triangle, a quadrilateral, and a polygon having sides more than four.

11. The display device according to claim 9, wherein the first spacer is disposed between the pixel electrode and the second substrate.

12. The display device according to claim 9, further comprising:

a touch detection element overlapping with the liquid crystal material, wherein the touch detection element is any one of an optical detecting element, a pressure sensitive type detecting element, and a capacitive type detecting element.

13. The display device according to claim 12, further comprising:

an LED backlight overlapping with the liquid crystal material.

14. A display device comprising:

a first substrate;

a gate electrode over the first substrate;

a semiconductor layer overlapping with the gate electrode;

a first insulating layer disposed between the gate electrode and the semiconductor layer;

a first conductive layer over and electrically connected the semiconductor layer;

a second conductive layer over and electrically connected the semiconductor layer;

a second insulating layer over the gate electrode, the first conductive layer, and the second conductive layer;

a pixel electrode over the second insulating layer, the pixel electrode electrically connected to the first conductive layer;

a second substrate opposed to the first substrate;

a liquid crystal material disposed between the first substrate and the second substrate; and

a first spacer disposed between the first substrate and the second substrate, the first spacer comprising a positive or negative type photosensitive resin; and

a second spacer disposed between the first substrate and the second substrate, the second spacer comprising a positive or negative type photosensitive resin,

wherein the first spacer and the second spacer are disposed in a region surrounded by a sealing region,

wherein each of the gate electrode, the first insulating layer, the semiconductor layer, the first conductive layer, and the pixel electrode overlaps with the first spacer,

wherein each of the gate electrode, the semiconductor layer, the first conductive layer, the second conductive layer, and the pixel electrode does not overlap with the second spacer, and

wherein the first spacer has a cross-section in which a width of a second substrate side end portion of the first spacer is larger than a width of a center portion of the first spacer, and the width of the center portion of the first spacer is larger than a width of a first substrate side end portion of the first spacer.

15. The display device according to claim 14, wherein a sectional shape of the first spacer in a radial direction is one selected from the group consisting of a circle, an ellipse, a triangle, a quadrilateral, and a polygon having sides more than four.

16. The display device according to claim 14, wherein the photosensitive resin is polyimide or acrylic.

17. The display device according to claim 14, wherein the first spacer is disposed between the pixel electrode and the second substrate.

18. The display device according to claim 14, further comprising:

a touch detection element overlapping with the liquid crystal material,

wherein the touch detection element is any one of an optical detecting element, a pressure sensitive type detecting element, and a capacitive type detecting element.

19. The display device according to claim 18, further comprising:

an LED backlight overlapping with the liquid crystal material.