Layered substrate with reduced blue dot defect density

An electrochromic (EC) system, comprising:

• an EC device comprising a substrate and a plurality of layers on the substrate;
• and
• a power supply electrically connected to the EC device and configured to provide a voltage to the EC device for controlling a tint of the EC device,
• wherein at least one active layer of the plurality of layers is lithiated for changing a tint of the EC device, wherein the at least one active layer is lithiated using a deposition process that uses one or more lithium (Li) targets, wherein the deposition process that uses the one or more Li targets provides a Li tungsten-oxide deposit area on the substrate that is over-concentrated with Li relative to at least one other remaining area on the substrate and on no more than 1.50% of manufactured EC devices.

A method of manufacturing a layered substrate for electrochromic (EC) devices, the method comprising:

• receiving, by a chamber, a plurality of respective substrates, wherein the plurality of respective substrates comprise respective sets of layers positioned thereon, wherein a respective at least one active layer of the respective sets of layers is lithiated for changing a tint of the EC devices;
• lithiating, in the chamber, the respective at least one active layer of the respective sets of layers using a deposition process that uses one or more lithium (Li) targets, and wherein lithiating the respective at least one active layer comprises depositing Li from the one or more Li targets on to a surface of one or more interior walls of the chamber;
• removing at least some Li from the surface of the one or more interior walls of the chamber;
• receiving, by the chamber, subsequent substrates, wherein the subsequent substrates comprise respective subsequent sets of layers positioned on the respective subsequent substrates and including a respective subsequent at least one active layer;
• and
• lithiating, in the chamber, the respective subsequent at least one active layer of the respective subsequent sets of layers using the deposition process after removing at least some of the Li from the surface of the one or more interior walls of the chamber, wherein no more than 1.50% of the respective subsequent sets of layers positioned on the respective subsequent substrates comprises a respective subsequent at least one active layer having a Li tungsten-oxide deposit area that is over-concentrated with Li relative to a surrounding area of the respective subsequent at least one active layer.