Method for producing an abrasion resistant coated substrate product

Claim 2

A chemical vapor deposition method for producing an abrasion wear resistant coated substrate product comprising: chemically de-greasing the surface of a parent substrate which is substantially optically transparent to light in the visible region of 350 to approximately 750 nanometers and which comprises a material selected from the group consisting of an amorphous material, a single crystal, polycrystalline materials, ceramic materials and mixtures thereof to remove hydrocarbon contamination; placing said substrate into a chemical vapor deposition reactor vacuum chamber and evacuating the air from said chamber; sputter-etching the surface of said substrate with energetic gas ions to remove traces of residual hydrocarbon and to preferentially reduce the concentration of alkali metal atoms and alkali metal oxides at the substrate surface; chemically vapor depositing at least one composite layer having a thickness in the range of about 1 μm to about 20 μm by chemically vapor depositing during a first cycle a substantially optically transparent first interlayer at least 1 μm up to 20 μm, thick onto said substrate; chemically vapor depositing during said first cycle a substantially optically transparent diamond-like carbon outer layer which is transparent to light in the visible region of 350 to approximately 750 nanometers and having a thickness of at least 50 Å thick onto said coated substrate; said first interlayer comprising a substantially optical transparent material devoid of alkali metal atoms and fluorine, which first interlayer is transparent to light in the visible region of 350 to approximately 750 nanometers and is selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof to form a strong chemical bond to said substrate and a strong chemical bond to said diamond-like carbon outer layer; cooling said coated substrate by extinguishing said deposition process and passing an inert gas over said substrate until the temperature of said substrate has reached substantially room temperature during said cool-down step; and recovering a coated substrate product exhibiting greatly improved wear resistance for severe abrasive environments.

Claim 3

The method of claim 1 wherein the thickness of said first interlayer and said diamond-like carbon outer layer are selected to maximize the reflection of light.

Claim 4

The method of claim 1 wherein the thickness of said diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 5

The method of claim 1 wherein the thickness of said first interlayer and said diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 6

The method of claim 1 wherein said composite layer comprises said first interlayer toward said substrate, a second interlayer which is transparent to light in the visible region of 350 to approximately 750 nanometers disposed immediately adjacent to said first interlayer and away from said substrate of a substantially optically transparent material devoid of alkali metal atoms and fluorine and capable of forming a strong chemical bond to said first interlayer and a strong chemical bond to diamond-like carbon, and said diamond-like carbon outer layer disposed immediately adjacent to said second interlayer and away from said substrate.

Claim 7

The method of claim 5 wherein said second interlayer comprises a substantially optically transparent metallic material capable of reflecting visible light selected from the group consisting of silicon, germanium, hafnium, molybdenum, tungsten, yttrium, tantalum, titanium and zirconium.

Claim 8

The method of claim 6 wherein the thickness of said first interlayer is in the range of about 5 Å to about 20 μm and the thickness of said second interlayer is in the range of about 10 Å to about 1000 Å.

Claim 9

The method of claim 5 wherein said second interlayer comprises a substantially optically transparent metallic material capable of reflecting visible light selected from the group consisting of vanadium, niobium, chromium, manganese, rhenium, technetium, iron, cobalt, iridium, rhodium, nickel, palladium, platinum, copper, silver, gold, zinc, ruthenium, indium, aluminum, tin, osmium, thallium, lead, antimony, bismuth and polonium.

Claim 10

The method of claim 8 wherein the thickness of said first interlayer is in the range of about 5 Å to about 20 μm and the thickness of said second interlayer is in the range of about 10 Å to about 1000 Å.

Claim 11

The method of claim 8 including a third interlayer disposed between said second interlayer and said diamond-like carbon outer layer of a substantially optically transparent material which third interlayer is transparent to light in the visible region of 350 to approximately 750 nanometers and is devoid of alkali metal atoms and fluorine to form a strong chemical bond with said second interlayer and said diamond-like carbon outer layer.

Claim 12

The method of claim 10 wherein said third interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium, oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof.

Claim 13

The method of claim 11 wherein the thickness of said first interlayer, said third interlayer and said diamond-like carbon outer layer are selected to minimize the reflection of light.

Claim 14

The method of claim 11 wherein the thickness of at least one of said composite layers, said third interlayer and said diamond-like carbon outer layer is selected to maximize the reflection of light.

Claim 15

The method of claim 11 wherein the thickness of said third interlayer and said diamond-like carbon outer layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 16

The method of claim 11 wherein the thickness of said first interlayer, said third interlayer and said diamond-like carbon outer layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 17

The method of claim 10 wherein said composite layer includes a chemically vapor deposited fourth interlayer disposed between said second interlayer and said diamond-like carbon outer layer of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond to said second interlayer and said diamond-like carbon outer layer.

Claim 18

The method of claim 16 wherein said first interlayer and said second interlayer comprise a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, aluminum oxide, cerium oxide, tin oxide, thorium oxide, lithium oxide, sodium oxide, potassium oxide, rubidium oxide, cesium oxide, francium oxide, beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, radium oxide, barium fluoride, cerium fluoride, magnesium fluoride, thorium fluoride, calcium fluoride, neodymium fluoride, lead fluoride, sodium fluoride, lithium fluoride, zinc selenide, zinc sulfide, mixtures thereof and chemically bonded combinations thereof.

Claim 19

The method of claim 16 wherein said fourth interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof and chemically bonded combinations thereof.

Claim 20

The method of claim 18 wherein the thicknesses of said first and second interlayers are in the range of about 5 Å to about 1 μm and the thickness of said fourth interlayer is in the range of about 1 μm to about 20 μm.

Claim 21

The method of claim 16 wherein the thickness of said first interlayer said second interlayer, said fourth interlayer and said diamond-like carbon outer layer are selected to minimize the reflection of light.

Claim 22

The method of claim 16 wherein the thickness of said first interlayer, said second interlayer, said fourth interlayer, and said diamond-like carbon outer layer are selected to maximize the reflection of light.

Claim 23

The method of claim 16 wherein the thickness of said second interlayer, said fourth interlayer and said diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 24

The method of claim 16 wherein the thickness of said first interlayer, said second interlayer, said fourth interlayer and said diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 25

The method of claim 5 wherein said first interlayer further comprises a substantially optically transparent material selected from the group consisting of aluminum oxide, cerium oxide, tin oxide, thorium oxide, lithium oxide, sodium oxide, potassium oxide, rubidium oxide, cesium oxide, francium oxide, beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, radium oxide, barium fluoride, cerium fluoride, magnesium fluoride, thorium fluoride, calcium fluoride, neodymium fluoride, lead fluoride, sodium fluoride, lithium fluoride, zinc selenide, zinc sulfide, mixtures thereof and chemically bonded combinations thereof.

Claim 26

The method of claim 5 wherein said second interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof and chemically bonded combinations thereof.

Claim 27

The method of claim 25 wherein the thickness of said first interlayer is in the range of about 5 Å to about 1 μm and the thickness of said second interlayer is in the range of about 1μm to about 20 μm.

Claim 28

The method of claim 26 wherein said first interlayer comprises silicon dioxide and said second interlayer comprises a chemically bonded combination of silicon oxide and silicon nitride.

Claim 29

The method of claim 21 wherein the thickness of said diamond-like carbon outer layer is at least 50 Å thick.

Claim 30

The method of claim 25 wherein the thickness of said first layer, said second interlayer and said diamond-like carbon outer layer are selected to minimize the reflection of light.

Claim 31

The method of claim 25 wherein the thickness of said first interlayer, said second interlayer and said diamond-like carbon outer layer are selected to maximize the reflection of light.

Claim 32

The method of claim 25 wherein the thickness of said second interlayer and said diamond-like carbon outer layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 33

The method of claim 25 wherein the thickness of said first interlayer, said second interlayer and said diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 34

The method of claim 25 wherein said composite layer comprises two different and separately deposited interlayers in place of said second interlayer and said diamond-like carbon outerlayer disposed immediately adjacent to the plurality of said interlayers and wherein each of said plurality of interlayers comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof and chemically bonded combinations thereof.

Claim 35

The method of claim 5 wherein said first interlayer further comprises a substantially optically transparent material selected from the group consisting of aluminum oxide, silicon oxide, silicon dioxide, silicon nitride, mixtures thereof and chemically bonded combinations thereof, and said second interlayer comprises substantially optically transparent silicon oxy-nitride.

Claim 36

The method of claim 34 wherein the substrate is a bar code scanner window.

Claim 37

The method of claim 34 wherein said first interlayer is about 10 Å to 1 μm thick.

Claim 38

The method of claim 34 wherein said second interlayer is about 1 μm to 20 μm thick.

Claim 39

The method of claim 37 wherein said first interlayer is aluminum oxide.

Claim 40

The method of claim 37 wherein said first interlayer is silicon dioxide.

Claim 41

The method of claim 37 wherein said first interlayer is silicon oxy-nitride and the atomic concentration of nitrogen in said second interlayer is greater than the atomic concentration of nitrogen in said first interlayer.

Claim 42

A chemical vapor deposition method for producing an abrasion wear resistant coated substrate product comprising: chemically de-greasing the surface of a parent substrate which is substantially optically transparent to light in the visible region of 350 to approximately 750 nanometers and which comprises a material selected from the group consisting of an amorphous material, a single crystal, polycrystalline materials, ceramic materials and mixtures thereof to remove hydrocarbon contamination; placing said substrate into a chemical vapor deposition reactor vacuum chamber and evacuating the air from said chamber; sputter-etching the surface of said substrate with energetic gas ions to remove traces of residual hydrocarbon and to preferentially reduce the concentration of alkali metal atoms and alkali metal oxides at the substrate surface; chemically vapor depositing a composite layer comprising a first composite having a thickness in the range of about 1 μm to about 20 μm and at least one second composite layer by chemically vapor depositing onto said substrate a first interlayer of a substantially optically transparent material to form a strong chemical bond to said substrate which first interlayer is transparent to light in the visible region of 350 to approximately 750 nanometers and which is selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, aluminum oxide, cerium oxide, tin oxide, thorium oxide, lithium oxide, sodium oxide, potassium oxide, rubidium oxide, cesium oxide, francium oxide, beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, radium oxide, barium fluoride, cerium fluoride, magnesium fluoride, thorium fluoride, calcium fluoride, neodymium fluoride, lead fluoride, sodium fluoride, lithium fluoride, zinc selenide, zinc sulfide, mixtures thereof, and chemically bonded combinations thereof; chemically vapor depositing a second interlayer onto and immediately adjacent to said first interlayer and away from said substrate of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond to said first interlayer and a strong chemical bond to diamond-like carbon; chemically vapor depositing a substantially optically transparent first diamond-like carbon layer which is transparent to light in the visible region of 350 to approximately 750 nanometers and having a thickness of at least 200 Å thick onto said coated substrate; chemically vapor depositing onto and immediately adjacent to said first diamond-like carbon layer a third interlayer of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond to diamond-like carbon; chemically vapor depositing a second substantially optically transparent diamond-like carbon layer onto said third interlayer; cooling said coated substrate by extinguishing said deposition process and passing an inert gas over said substrate until the temperature of said substrate has reached substantially room temperature during said cool-down step; and recovering a coated substrate product exhibiting greatly improved wear resistance for severe abrasive environments.

Claim 43

A chemical vapor deposition method for producing an abrasion wear resistant coated substrate product comprising: chemically de-greasing the surface of a parent substrate which is substantially optically transparent to light in the visible region of 350 to approximately 750 nanometers and which comprises a material selected from the group consisting of an amorphous material, a single crystal, polycrystalline materials, ceramic materials and mixtures thereof to remove hydrocarbon contamination; placing said substrate into a chemical vapor deposition reactor vacuum chamber and evacuating the air from said chamber; sputter-etching the surface of said substrate with energetic gas ions to remove traces of residual hydrocarbon and to preferentially reduce the concentration of alkali metal atoms and alkali metal oxides at the substrate surface; chemically vapor depositing a composite layer comprising a first composite having a thickness in the range of about 1 μm to about 20 μm and at least one second composite layer by chemically vapor depositing onto said substrate a first interlayer of a substantially optically transparent material to form a strong chemical bond to said substrate which first interlayer is transparent to light in the visible region of 350 to approximately 750 nanometers and which is selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, aluminum oxide, cerium oxide, tin oxide, thorium oxide, lithium oxide, sodium oxide, potassium oxide, rubidium oxide, cesium oxide, francium oxide, beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, radium oxide, barium fluoride, cerium fluoride, magnesium fluoride, thorium fluoride, calcium fluoride, neodymium fluoride, lead fluoride, sodium fluoride, lithium fluoride, zinc selenide, zinc sulfide, mixtures thereof, and chemically bonded combinations thereof; chemically vapor depositing a second interlayer onto and immediately adjacent to said first interlayer and away from said substrate of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond to said first interlayer and a strong chemical bond to diamond-like carbon; chemically vapor depositing a substantially optically transparent first diamond-like carbon layer which is transparent to light in the visible region of 350 to approximately 750 nanometers and having a thickness of at least 200 Å thick onto said coated substrate; chemically vapor depositing onto and immediately adjacent to said first diamond-like carbon layer a third interlayer of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond to diamond-like carbon; chemically vapor depositing a second substantially optically transparent diamond-like carbon layer onto said third interlayer; cooling said coated substrate by extinguishing said deposition process and passing an inert gas over said substrate until the temperature of said substrate has reached substantially room temperature during said cool-down step; and recovering a coated substrate product exhibiting greatly improved wear resistance for severe abrasive environments.

Claim 44

The method of claim 41 wherein said second interlayer and said third interlayer comprise a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, yttrium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof.

Claim 45

The method of claim 41 wherein the thickness of said second interlayer is in the range of about 1 μm to about 20 μm.

Claim 46

The method of claim 43 wherein the first interlayer comprises silicon dioxide and said second interlayer comprises a chemically bonded combination of silicon oxide and silicon nitride.

Claim 47

The method of claim 41 wherein said first composite layer comprises at least one pair of separately deposited said second interlayers.

Claim 48

The method of claim 41 wherein the thickness of said first interlayer, said second interlayer and said third interlayer is at least 2 μm thick.

Claim 49

The method of claim 41 wherein the thickness of said first diamond-like carbon layer and said second diamond-like carbon layer is at least 50 Å thick.

Claim 50

The method of claim 41 wherein the thickness of at least one of said first interlayer, said second interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer is selected to minimize the reflection of light.

Claim 51

The method of claim 41 wherein the thickness of at least one of said first interlayer, said second interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer is selected to maximize the reflection of light.

Claim 52

The method of claim 41 wherein the thickness of said second interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 53

The method of claim 41 wherein the thickness of said first interlayer, said second interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 54

The method of claim 44 wherein said third interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, yttrium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof.

Claim 55

The method of claim 52 wherein said second interlayer comprises a substantially optically transparent metallic material capable of reflecting visible light selected from the group consisting of silicon, germanium, hafnium, molybdenum, tungsten, yttrium, tantalum, titanium and zirconium.

Claim 56

The method of claim 52 wherein the thickness of said first interlayer is in the range of about 5 Å to about 20 μm and the thickness of said second interlayer is in the range of about 10 Å to about 1000 Å.

Claim 57

The method of claim 52 wherein said second interlayer comprises a substantially optically transparent metallic material capable of reflecting visible light selected from the group consisting of vanadium, niobium, chromium, manganese, rhenium, technetium, iron, cobalt, iridium, rhodium, nickel, palladium, platinum, copper, silver, gold, zinc, ruthenium, indium, aluminum, tin, osmium, thallium, lead, antimony, bismuth and polonium.

Claim 58

The method of claim 55 wherein the thickness of said first interlayer is in the range of about 5 Å to about 20 μm and the thickness of said second interlayer is in the range of about 10 Å to about 1000 Å.

Claim 59

The method of claim 55 including a fourth interlayer disposed between said second interlayer and said first diamond-like carbon layer of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond with said second interlayer and said first diamond-like carbon layer.

Claim 60

The method of claim 57 wherein said fourth interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof.

Claim 61

The method of claim 57 wherein the thickness of at least one of said first interlayer, said fourth interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer is selected to maximize the reflection of light.

Claim 62

The method of claim 57 wherein the thickness of at least one of said first interlayer, said fourth interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer is selected to maximize the reflection of light.

Claim 63

The method of claim 57 wherein the thickness of said fourth interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 64

The method of claim 57 wherein the thickness of said first interlayer, said fourth interlayer, said third interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 65

The method of claim 41 wherein said first composite layer includes a fifth interlayer disposed between said second interlayer and said first diamond-like carbon layer of a substantially optically transparent material devoid of alkali metal atoms and fluorine to form a strong chemical bond with said second interlayer and said diamond-like carbon outer layer.

Claim 66

The method of claim 63 wherein said third interlayer and said fifth interlayer comprise a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, mixtures thereof, and chemically bonded combinations thereof.

Claim 67

The method of claim 64 wherein the thickness of said first and second interlayers are at least about 5 Å and less than 20 μm and the thickness of said fifth interlayer is at least about 1 μm and less than 20 μm.

Claim 68

The method of claim 63 wherein said second interlayer comprises a substantially optically transparent material selected from the group consisting of silicon nitride, titanium nitride, tantalum nitride, hafnium nitride, zirconium nitride, boron nitride, yttrium oxide, germanium oxide, hafnium oxide, silicon oxide, silicon dioxide, tantalum oxide, titanium oxide, zirconium oxide, silicon carbide, germanium carbide, aluminum oxide, cerium oxide, tin oxide, thorium oxide, lithium oxide, sodium oxide, potassium oxide, rubidium oxide, cesium oxide, francium oxide, beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, radium oxide, barium fluoride, cerium fluoride, magnesium fluoride, thorium fluoride, calcium fluoride, neodymium fluoride, lead fluoride, sodium fluoride, lithium fluoride, zinc selenide, zinc sulfide, mixtures thereof, and chemically bonded combinations thereof.

Claim 69

The method of claim 63 wherein the thickness of at least one of said first interlayer, said second interlayer, said fifth interlayer, said first diamond-like carbon layer, said third interlayer and said second diamond-like carbon layer is selected to minimize the reflection of light.

Claim 70

The method of claim 63 wherein the thickness of at least one of said first interlayer, said second interlayer, said fifth interlayer, said first diamond-like carbon layer, said third interlayer and said second diamond-like carbon layer is selected to maximize the reflection of light.

Claim 71

The method of claim 63 wherein the thickness of said second interlayer, said third interlayer, said fifth interlayer, said first diamond-like carbon layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.

Claim 72

The method of claim 63 wherein the thickness of said first interlayer, said second interlayer, said third interlayer, said fifth interlayer, said first diamond-like layer and said second diamond-like carbon layer corresponds to integer multiples of quarter wavelength optical thickness.