Touch sensitive display employing an SOI substrate and integrated sensing circuitry

• US 20090195511A1
• Filed: 02/04/2008
• Published: 08/06/2009
• Est. Priority Date: 02/04/2008
• Status: Abandoned Application

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Mozdy, Eric John, Dawson-Elli, David Francis, Cites, Jeffrey Scott, Williams, Carlo Anthony Kosik
• Application Number:
  US12/012,564
• Publication Number:
  US 20090195511A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells

Abstract

Methods and apparatus for producing a touch sensitive LCD employing a semiconductor on glass (SiOG) structure provide for: a glass or glass-ceramic substrate; a single crystal semiconductor layer bonded to the glass or glass-ceramic substrate; display circuitry including a plurality of thin-film transistors disposed on the single crystal semiconductor layer and forming a matrix of display pixels; display control circuitry operable to drive the display circuitry to produce viewable images; and sensing circuitry operable to detect electrical characteristic changes in one or more of the single crystal semiconductor layer and the display circuitry, the electrical characteristic changes resulting from user touch events.

Claims

1. A display, comprising:

a glass or glass-ceramic substrate;

a single crystal semiconductor layer bonded to the glass or glass-ceramic substrate;

display circuitry including a plurality of thin-film transistors disposed on the single crystal semiconductor layer and forming a matrix of display pixels;

display control circuitry operable to drive the display circuitry to produce viewable images; and

sensing circuitry operable to detect electrical characteristic changes in one or more of the single crystal semiconductor layer and the display circuitry, the electrical characteristic changes resulting from user touch events.

2. The display of claim 1, wherein:

the display circuitry includes a plurality of liquid crystals associated with the display pixels and operable to produce the images; and

the electrical characteristic changes resulting from user touch events include dielectric constant changes in one or more of the liquid crystals.

3. The display of claim 1, wherein the electrical characteristic changes resulting from user touch events include dielectric constant changes in the single crystal semiconductor layer.

4. The display of claim 1, wherein the electrical characteristic changes resulting from user touch events include changes in performance characteristics in the matrix of display pixels.

5. The display of claim 1, wherein the single crystal semiconductor layer exhibits high uniformity with substantially no grain boundaries.

6. The display of claim 1, wherein the single crystal semiconductor layer exhibits an n-type carrier mobility of greater than about 400 cm²/V·

s.

7. The display of claim 6, wherein the single crystal semiconductor layer exhibits an n-type carrier mobility of greater than about 450 cm²/V·

s.

8. The display of claim 7, wherein the single crystal semiconductor layer exhibits an n-type carrier mobility of between about 450-600 cm²/V·

s.

9. The display of claim 1, wherein the single crystal semiconductor layer exhibits a p-type carrier mobility of greater than about 160 cm²/V·

s.

10. The display of claim 9, wherein the single crystal semiconductor layer exhibits an p-type carrier mobility of greater than about 200 cm²/V·

s.

11. The display of claim 1, wherein the single crystal semiconductor layer is taken from the group consisting of:

silicon (Si), germanium-doped silicon (SiGe), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), GaP, and InP.

12. The display of claim 1, wherein:

the glass or glass-ceramic substrate includes, in order, a bulk layer, an enhanced positive ion concentration layer, a reduced positive ion concentration layer, where the enhanced positive ion concentration layer contains substantially all modifier positive ions from the reduced positive ion concentration layer as a result of migration; and

a semiconductor oxide layer is located between the reduced positive ion concentration layer of the substrate and the single crystal semiconductor layer.

13. A display, comprising:

a glass or glass-ceramic substrate;

a single crystal semiconductor layer bonded to the glass or glass-ceramic substrate;

display circuitry including a plurality of thin-film transistors disposed on the single crystal semiconductor layer and forming a matrix of display pixels, and a plurality of liquid crystals associated with the display pixels;

display control circuitry operable to drive the display circuitry to produce viewable images; and

sensing circuitry operable to detect changes in dielectric constant in one or more of the liquid crystals resulting from user touch events,

wherein the single crystal semiconductor layer exhibits an n-type carrier mobility of greater than about 400 cm²/V·

s.

14. The display of claim 13, wherein the single crystal semiconductor layer exhibits high uniformity with substantially no grain boundaries.

15. The display of claim 13, wherein the sensing circuitry is operable to detect the changes in dielectric constant in all the liquid crystals of the display circuitry each video frame.

16. The display of claim 13, wherein the single crystal semiconductor layer is taken from the group consisting of:

silicon (Si), germanium-doped silicon (SiGe), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), GaP, and InP.