Electroluminescent device and a method of making same

Claim 2

In an electroluminescent device comprising a first electrode, a first dielectric layer overlying the first electrode, a continuous phosphor layer overlying the first dielectric layer, a second dielectric layer overlying the phosphor layer and a second electrode overlying the second dielectric layer, the improvement comprising: said first electrode comprising tin oxide having a textured surface adjacent the first dielectric layer and an opposed surface which is smooth and said phosphor layer conformally overlying said textured surface.

Claim 3

The device of claim 1 wherein the first electrode overlies a smooth, specularly reflecting surface of a substrate with the smooth surfaces of the substrate and the first electrode adjacent one another.

Claim 4

The device of claim 2 wherein the substrate and the first electrode are light transmissive.

Claim 5

The device of claim 3 wherein said first electrode comprises a plurality of sub-electrodes spaced apart from one another on the surface of the substrate.

Claim 6

The device of claim 1 wherein said first electrode has a minimum thickness of about 100 nanometers and said textured surface has a minimum feature size of about 100 nanometers.

Claim 7

The device of claim 5 wherein said textured surface has a feature size between about 100 and 800 nanometers.

Claim 8

The device of claim 6 wherein said textured surface has a feature size between about 200 and 500 nanometers.

Claim 9

In an electroluminescent device comprising a substrate having a smooth, specularly reflecting surface with a first electrode overlying said substrate surface and a continuous phosphor layer overlying said first electrode; the improvement comprising: said first electrode comprising tin oxide having a surface opposed to the surface thereof adjacent to said substrate surface which is extended and said phosphor layer conformally overlying said textured surface.

Claim 10

In an electroluminescent device comprising a substrate having a smooth, specularly reflecting surface with a first electrode overlying said substrate surface and a continuous phosphor layer overlying said first electrode; the improvement comprising: said first electrode comprising tin oxide having a surface opposed to the surface thereof adjacent to said substrate surface which is extended and said phosphor layer conformally overlying said textured surface.

Claim 11

The device of claim 8 wherein said first electrode has a minimum thickness of about 100 nanometers and said textured surface has a minimum feature size of about 100 nanometers.

Claim 12

The device of claim 9 wherein said textured surface has a feature size between about 100 and 800 nanometers.

Claim 13

The device of claim 10 wherein said textured surface has a feature size between about 200 and 500 nanometers.

Claim 14

In a method of forming an electroluminescent device comprising the steps of forming a first electrode on a smooth, specularly reflecting surface of a substrate, forming a first dielectric layer overlying said first electrode, forming a phosphor layer overlying said first dielectric layer, forming a second dielectric layer overlying said phosphor layer and forming a second electrode overlying said second dielectic layer; the improvement comprising: depositing a tin oxide first electrode onto said substrate surface held at a temperature greater than about 350° C. by chemical vapor deposition from an atmosphere containing tin, oxygen, hydrogen and a conductivity modifying dopant whereby the surface of said electrode opposed to said substrate surface has a dominant peak-to-valley texture greater than 100 nanometers; and wherein said tin oxide first electrode has a textured surface adjacent the first dielectric layer and an opposed surface which is smooth.

Claim 15

In a method of forming an electroluminescent device comprising the steps of forming a first electrode on a smooth, specularly reflecting surface of a substrate, forming a first dielectric layer overlying said first electrode, forming a phosphor layer overlying said first dielectric layer, forming a second dielectric layer overlying said phosphor layer and forming a second electrode overlying said second dielectic layer; the improvement comprising: depositing a tin oxide first electrode onto said substrate surface held at a temperature greater than about 350° C. by chemical vapor deposition from an atmosphere containing tin, oxygen, hydrogen and a conductivity modifying dopant whereby the surface of said electrode opposed to said substrate surface has a dominant peak-to-valley texture greater than 100 nanometers; and wherein said tin oxide first electrode has a textured surface adjacent the first dielectric layer and an opposed surface which is smooth.

Claim 16

The method of claim 12 wherein said atmosphere further comprises a halogen.

Claim 17

The method of claim 13 wherein said halogen is chlorine.

Claim 18

The method of claim 12 wherein said first electrode is deposited to a thickness between about 100 and 1000 nanometers.

Claim 19

The method of claim 15 wherein the peak-to-valley texture of said first electrode surface is between about 250 and 500 nanometers.