Durable tungsten-doped tin-fluorophosphate glasses

• US 20080146431A1
• Filed: 10/06/2006
• Published: 06/19/2008
• Est. Priority Date: 10/06/2006
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Aitken, Bruce Gardiner, Quesada, Mark Alejandro, Koval, Shari Elizabeth
• Granted Patent: US 7,615,506 B2
• Time in Patent Office: Days
• US Class Current: 501/44
• CPC Class Codes: C03C 3/247 containing fluorine and phosphorus
• CPC Class Codes: C03C 8/24 Fusion seal compositions being frit compositions having non-frit additions, i.e. for use as seals between dissimilar materials, e.g. glass and metal; Glass solders

Abstract

Tungsten-doped tin-fluorophosphate glasses are described herein which exhibit excellent humidity resistance, thermal resistance, and have a low glass transition temperature which makes them suitable for low temperature sealing applications, such as for encapsulating electronic components. In one embodiment, these glasses comprise 55-75% Sn, 4-14% P, 6-24% O, 4-22% F, and 0.15-15% W on a weight percent elemental basis.

Claims

1. A homogeneous glass comprising:

Sn (55-75 wt %)

P (4-14 wt %)

O (6-24 wt %)

F (4-22 wt %)

W (0.5-15 wt %) and having a glass transition temperature T_g<

160°

C.

2. The homogeneous glass of claim 1, wherein a source of said W is tungstic acid (H₂WO₄).

3. The homogeneous glass of claim 1, having a pale coloration which is suitable for sealing light emitting devices.

4. The homogeneous glass of claim 1, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (58-68 wt %)

P (5-11 wt %)

O (11-21 wt %)

F (6-13 wt %)

W (1-10 wt %).

5. The homogeneous glass of claim 1, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (59-68 wt %)

P (6-11 wt %)

O (13-20 wt %)

F (6-11 wt %)

W (1-6 wt %).

6. The homogeneous glass of claim 1, having a weight gain of less than 2% after exposure to air at atmospheric pressure, a temperature of 85°

C., and a moisture content of 85% relative humidity, for a period of at least 1000 hours.

7. An encapsulated article, comprising:

a device encapsulated in a homogenous glass including, in weight percent on an elemental basis, 55-75% Sn, 4-14% P, 6-24% O, 4-22% F, and 0.15-15% W, said homogenous glass having a glass transition temperature T_g<

160°

C.

8. The encapsulated article of claim 7, wherein a source of said W is tungstic acid (H₂WO₄).

9. The encapsulated article of claim 7, wherein said device is a selected one of:

an organic-electronic device including;

an OLED;

a PLED,

a photovoltaic; and

a thin film transistor;

a thin-film sensor;

an optoelectronic device including;

an optical switch; and

a waveguide;

a photovoltaic device;

a food container;

or

a medicine container.

10. A method for encapsulating a device, said method comprising the steps of:

depositing a homogeneous glass over at least a portion of said device; and

heat treating said homogeneous glass that was deposited over said at least a portion of said device, wherein said homogeneous glass has a glass transition temperature T_g<

160°

C. and has a composition;

Sn (55-75 wt %)

P (4-14 wt %)

O (6-24 wt %)

F (4-22 wt %)

W (0.5-15 wt %).

11. The method of claim 10, wherein a source of said W is tungstic acid (H₂WO₄).

12. The method of claim 10, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (58-68 wt %)

P (5-11 wt %)

O (11-21 wt %)

F (6-13 wt %)

W (1-10 wt %).

13. The method of claim 10, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (59-68 wt %)

P (6-11 wt %)

O (13-20 wt %)

F (6-11 wt %)

W (1-6 wt %).

14. The method of claim 10, wherein said device is a selected one of:

an organic-electronic device including;

an OLED;

a PLED,

a photovoltaic; and

a thin film transistor;

a thin-film sensor;

an optoelectronic device including;

an optical switch; and

a waveguide;

a photovoltaic device;

a food container;

or

a medicine container.

15. A package comprising:

a plate; and

a sealing glass plate which includes a swelled portion that is a hermetic seal which connects said plate to said sealing glass plate and also creates a gap between said plate and said sealing glass plate, wherein said sealing glass plate has a glass transition temperature T_g<

160°

C. and has a composition;

Sn (55-75 wt %)

P (4-14 wt %)

O (6-24 wt %)

F (4-22 wt %)

W (0.5-15 wt %).

16. The package of claim 15, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (58-68 wt %)

P (5-11 wt %)

O (11-21 wt %)

F (6-13 wt %)

W (1-10 wt %).

17. The package of claim 15, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (59-68 wt %)

P (6-11 wt %)

O (13-20 wt %)

F (6-11 wt %)

W (1-6 wt %).

18. A package comprising:

a first plate;

a second plate; and

a frit made from a homogeneous glass, wherein said frit was heated in a manner that caused said frit to melt and form a hermetic seal which connects said first plate to said second plate, wherein said homogeneous glass has a glass transition temperature T_g<

160°

C. and has a composition;

Sn (55-75 wt %)

P (4-14 wt %)

O (6-24 wt %)

F (4-22 wt %)

W (0.5-15 wt %).

19. The package of claim 18, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (58-68 wt %)

P (5-11 wt %)

O (11-21 wt %)

F (6-13 wt %)

W (1-10 wt %).

20. The package of claim 18, wherein said homogenous glass has an O/F ratio greater than 0.85 and has a preferred composition:

Sn (59-68 wt %)

P (6-11 wt %)

O (13-20 wt %)

F (6-11 wt %)

W (1-6 wt %).