Fabrication of low defectivity electrochromic devices
Prior electrochromic devices frequently suffer from high levels of defectivity. The defects may be manifest as pin holes or spots where the electrochromic transition is impaired. This is unacceptable for many applications such as electrochromic architectural glass. Improved electrochromic devices with low defectivity can be fabricated by depositing certain layered components of the electrochromic device in a single integrated deposition system. While these layers are being deposited and/or treated on a substrate, for example a glass window, the substrate never leaves a controlled ambient environment, for example a low pressure controlled atmosphere having very low levels of particles. These layers may be deposited using physical vapor deposition.
1. An electrochromic device comprising:
a first conductive layer;
a single electrochromic layer;
an ion conductor layer;
a nickel oxide counter electrode layer, wherein nickel oxide is a major component of the nickel oxide counter electrode layer, wherein the nickel oxide counter electrode layer is a layer of nickel oxide material doped with (i) a first dopant of tungsten and (ii) a second dopant of tantalum, and wherein a weight percent ratio of tungsten to nickel in the nickel oxide counter electrode layer is in a range of 0.40 to 0.60;
a second conductive layer, wherein the second conductive layer is transparent; and
an anti-reflective layer disposed on one or both of the first conductive layer and the second conductive layer.
2. The electrochromic device of claim 1 , wherein the anti-reflective layer comprises an oxide material or a nitride material.
3. The electrochromic device of claim 1 , wherein the single electrochromic layer comprises a tungsten oxide based material.
4. The electrochromic device of claim 3 , wherein the tungsten oxide based material is doped with molybdenum, vanadium, or titanium.
5. The electrochromic device of claim 3 , wherein the tungsten oxide based material is doped with one or more of lithium, sodium, or potassium.
6. The electrochromic device of claim 1 , wherein the first conductive layer and the second conductive layer each comprise one of a conductive oxide material, a conductive metallic material, and a conductive metal nitride material.
7. The electrochromic device of claim 1 , wherein each of the single electrochromic layer, the ion conductor layer, and the nickel oxide counter electrode layer is a layer of solid state and inorganic material.
8. The electrochromic device of claim 1 , further comprising a hermetic sealing layer disposed over the first conductive layer, the single electrochromic layer, the ion conductor layer, the nickel oxide counter electrode layer, the second conductive layer, and the anti-reflective layer of the electrochromic device.
9. The electrochromic device of claim 1 , wherein the anti-reflective layer is disposed on the second conductive layer.
10. The electrochromic device of claim 1 , wherein the first conductive layer is a transparent conductive layer.
11. The electrochromic device of claim 1 , wherein the nickel oxide material of the nickel oxide counter electrode layer is amorphous or substantially amorphous.