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 . (canceled)
2 . A method of fabricating an electrochromic device, the method comprising:
(a) receiving a substrate comprising a first transparent conductive layer or forming the first transparent conductive layer on the substrate;
(b) after (a), cleaning the substrate to remove contaminants therefrom, wherein the substrate is cleaned through mechanical scrubbing and/or ultrasonic conditioning;
(c) forming an electrochromic stack on the first transparent conductive layer, the electrochromic stack comprising at least an electrochromic layer comprising an electrochromic material and a counter electrode layer comprising a counter electrode material; and
(d) after (c), forming a second transparent conductive layer on the electrochromic stack.
3 . The method of claim 2 , wherein the substrate is cleaned through mechanical scrubbing.
4 . The method of claim 2 , wherein the substrate is cleaned through ultrasonic conditioning.
5 . The method of claim 2 , further comprising:
after (b), forming a trench in the first transparent conductive layer through laser scribing.
6 . The method of claim 5 , further comprising:
after forming the trench in the first transparent conductive layer, cleaning the substrate a second time to remove debris caused by forming the trench in the first transparent conductive layer.
7 . The method of claim 6 , wherein the cleaning the substrate the second time comprises mechanically scrubbing the substrate.
8 . The method of claim 6 , wherein cleaning the substrate the second time comprises performing ultrasonic conditioning.
9 . The method of claim 6 , wherein cleaning the substrate the second time is performed prior to (c).
10 . The method of claim 2 , wherein (c) occurs after (b).
11 . The method of claim 2 , wherein the method is performed in an integrated deposition system such that (a)-(d) each occur in a controlled ambient environment.
12 . The method of claim 11 , wherein the controlled ambient environment provides a pressure below atmospheric pressure during one or more of (a)-(d).
13 . The method of claim 11 , wherein (a)-(d) are performed without being exposed to an external environment.
14 . The method of claim 2 , further comprising plasma etching the substrate.
15 . 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 cleaning station configured to clean the substrate; and
(iv) a controller comprising program instructions for passing the substrate through the cleaning station and deposition stations in a manner that cleans the substrate and deposits a stack on the substrate, the stack comprising the layer of electrochromic material and a layer of counter electrode material.
16 . The apparatus of claim 15 , wherein the cleaning station is configured to clean the substrate through mechanical scrubbing.
17 . The apparatus of claim 15 , wherein the cleaning station is configured to clean the substrate through ultrasonic conditioning.
18 . The apparatus of claim 15 , wherein the controller comprises program instructions for cleaning the substrate prior to depositing the stack on the substrate.
19 . The apparatus of claim 15 , further comprising a laser scribing station configured to form a trench on the substrate through laser scribing.
20 . The apparatus of claim 19 , wherein the controller comprises program instructions for cleaning the substrate after the trench is formed on the substrate in the laser scribing station.
21 . The apparatus of claim 19 , wherein the controller comprises program instructions for cleaning the substrate both (a) before the trench is formed on the substrate in the laser scribing station, and (b) after the trench is formed on the substrate in the laser scribing station.
22 . The apparatus of claim 15 , further comprising a plasma etch station configured to plasma etch the substrate.