Defect-mitigation layers in electrochromic devices
Electrochromic devices and methods may employ the addition of a defect-mitigating insulating layer which prevents electronically conducting layers and/or electrochromically active layers from contacting layers of the opposite polarity and creating a short circuit in regions where defects form. In some embodiments, an encapsulating layer is provided to encapsulate particles and prevent them from ejecting from the device stack and risking a short circuit when subsequent layers are deposited. The insulating layer may have an electronic resistivity of between about 1 and 10 8 Ohm-cm. In some embodiments, the insulating layer contains one or more of the following metal oxides: aluminum oxide, zinc oxide, tin oxide, silicon aluminum oxide, cerium oxide, tungsten oxide, nickel tungsten oxide, and oxidized indium tin oxide. Carbides, nitrides, oxynitrides, and oxycarbides may also be used.
1. A method of fabricating an electrochromic (EC) device, the method comprising:
(a) receiving a substrate comprising a first transparent conductive (TC) layer or forming the first TC layer on the substrate, wherein the substrate is a glass substrate on which the EC device is to be formed;
(b) forming an EC layer thereon through sputtering;
(c) forming an ion conducting (IC) layer thereon;
(d) after (c), performing a particle removal operation by applying acoustic energy that is megasonic or supersonic, wherein the particle removal operation removes particles that formed on the substrate during (a)-(c); and
(e) after (d), completing fabrication of the EC device.
2. The method of claim 1 , further comprising forming a defect-mitigating insulating layer (DMIL) after (d).
3. The method of claim 1 , wherein (d) is performed outside a vacuum environment of a system used to deposit layers of the EC device.
4. The method of claim 3 , further comprising:
prior to (b), cutting the substrate on which the EC device is to be fabricated; and
performing at least operation (d) on the cut substrate.
5. The method of claim 1 , wherein (b) comprises forming the EC layer on the substrate while the substrate is oriented vertically.
6. The method of claim 1 , wherein the EC layer comprises an electrochromic material that is cathodically-coloring or anodically-coloring.
7. An apparatus for fabricating an electrochromic device, the apparatus comprising:
(i) a first deposition station containing a first target comprising a first material for depositing a layer of an electrochromic material on a substrate through sputtering when the substrate is positioned in the first deposition station, wherein the substrate is a glass substrate on which the electrochromic device is to be formed;
(ii) one or more additional deposition stations configured to deposit one or more additional layers of the electrochromic device;
(iii) a particle-removal device for removing particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed; and
(iv) a controller comprising:
program instructions for passing the substrate through the deposition stations in a manner that sequentially deposits a stack on the substrate, the stack comprising the layer of electrochromic material and a layer of ion conductor material; and
program instructions for operating the particle-removal device to remove particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed by applying acoustic energy that is megasonic or supersonic, wherein the particles that are removed are particles that form on the substrate during deposition of the layer of electrochromic material and/or the layer of ion conductor material.
8. The apparatus of claim 7 , wherein the program instructions comprise instructions for operating the particle-removal device to remove particles after forming the layer of ion conductor material.
9. The apparatus of claim 8 , wherein the program instructions comprise instructions for operating the particle-removal device to remove particles after completing fabrication of the layer of ion conductor material.
10. The apparatus of claim 7 , further comprising: (v) an electrode deposition station configured to deposit an electrode layer on the electrochromic stack when the substrate having the electrochromic stack is positioned in the third deposition station, and wherein the electrode layer comprises a transparent electronically conductive material.
11. The apparatus of claim 7 , further comprising a substrate holder configured to provide the substrate in a vertical orientation when positioned for deposition in the first deposition station.
12. The apparatus of claim 7 , further comprising a lithium deposition station containing a lithium target for depositing lithium on or within the layer of electrochromic material or on or within a layer of counter electrode material when the substrate is positioned in the lithium deposition station.
13. The apparatus of claim 12 , wherein the program instructions comprise instructions for performing two lithiation operations.
14. The apparatus of claim 7 , further comprising: (v) a defect mitigating insulating layer deposition station configured to deposit a defect-mitigating insulating layer that is substantially transparent.
15. A method of fabricating an electrochromic (EC) device, the method comprising:
(a) receiving a substrate comprising a first transparent conductive (TC) layer or forming the first TC layer on the substrate;
(b) forming an EC layer thereon;
(c) forming an ion conducting (IC) layer thereon;
(d) after (c), performing a particle removal operation, wherein (d) is performed outside of a vacuum environment of a system used to deposit layers of the EC device; and
(e) after (d), completing fabrication of the EC device.
16. The method of claim 15 , further comprising:
prior to (b), cutting the substrate on which the EC device is to be fabricated; and
performing at least operation (d) on the cut substrate.
17. The method of claim 15 , wherein (d) comprises applying a contact cleaner.
18. A method of fabricating an electrochromic (EC) device, the method comprising:
(a) receiving a substrate comprising a first transparent conductive (TC) layer or forming the first TC layer on the substrate;
(b) forming an EC layer thereon;
(c) forming an ion conducting (IC) layer thereon;
(d) after (c), performing a particle removal operation by applying thermal energy using a lamp or laser, wherein the particle removal operation cleans the surface of the substrate; and
(e) after (d), completing fabrication of the EC device.
19. A method of fabricating an electrochromic (EC) device, the method comprising:
(a) receiving a substrate comprising a first transparent conductive (TC) layer or forming the first TC layer on the substrate;
(b) forming an EC layer thereon;
(c) forming an ion conducting (IC) layer thereon;
(d) after (c), performing a particle removal operation by applying thermal energy using a non-radiative mechanism, wherein the particle removal operation cleans the surface of the substrate; and
(e) after (d), completing fabrication of the EC device.
20. An apparatus for fabricating an electrochromic device, the apparatus comprising:
(i) a first deposition station containing a first target comprising a first material for depositing a layer of an electrochromic material on a substrate when the substrate is positioned in the first deposition station, wherein the first deposition station is provided in a vacuum environment;
(ii) one or more additional deposition stations configured to deposit one or more additional layers of the electrochromic device;
(iii) a particle-removal device for removing particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed, wherein the particle removal device operates outside of the vacuum environment; and
(iv) a controller comprising:
program instructions for passing the substrate through the deposition stations in a manner that sequentially deposits a stack on the substrate, the stack comprising the layer of electrochromic material and a layer of ion conductor material; and
program instructions for operating the particle-removal device to remove particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed.
21. An apparatus for fabricating an electrochromic device, the apparatus comprising:
(i) a first deposition station containing a first target comprising a first material for depositing a layer of an electrochromic material on a substrate when the substrate is positioned in the first deposition station;
(ii) one or more additional deposition stations configured to deposit one or more additional layers of the electrochromic device;
(iii) a particle-removal device for removing particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed, thereby cleaning the substrate; and
(iv) a controller comprising:
program instructions for passing the substrate through the deposition stations in a manner that sequentially deposits a stack on the substrate, the stack comprising the layer of electrochromic material and a layer of ion conductor material; and
program instructions for operating the particle-removal device to remove particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed by applying thermal energy using a lamp or laser.
22. An apparatus for fabricating an electrochromic device, the apparatus comprising:
(i) a first deposition station containing a first target comprising a first material for depositing a layer of an electrochromic material on a substrate when the substrate is positioned in the first deposition station;
(ii) one or more additional deposition stations configured to deposit one or more additional layers of the electrochromic device;
(iii) a particle-removal device for removing particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed, thereby cleaning the substrate; and
(iv) a controller comprising:
program instructions for passing the substrate through the deposition stations in a manner that sequentially deposits a stack on the substrate, the stack comprising the layer of electrochromic material and a layer of ion conductor material; and
program instructions for operating the particle-removal device to remove particles from the surface of the substrate and/or the surface of the electrochromic device before it is fully-formed by applying thermal energy using a non-radiative mechanism.