Electrochromic device including a means for preventing ion migration and a process of forming the same

An electrochromic device comprising:

• a substrate;
• an electrochromic stack comprising:
• an electrochromic layer or a counter electrode layer over the substrate, wherein the electrochromic or counter electrode layer includes a mobile ion;
• a first transparent conductive layer over the substrate and including Ag;
• and
• a barrier layer disposed between first transparent conductive layer and the electrochromic or counter electrode layer, wherein the barrier layer prevents the mobile ion from migrating into the first transparent conductive layer and Ag from migrating into the electrochromic layer or counter electrode layer;
• and
• a second transparent conductive layer.

A process of forming an electrochromic device comprising:

• providing a substrate;
• forming an electrochromic layer or a counter electrode layer over the substrate, wherein after forming the electrochromic or counter electrode layer, the electrochromic or counter electrode layer includes a mobile ion;
• forming a barrier layer over the substrate;
• and
• forming a first transparent conductive layer over the substrate and including Ag,
• wherein forming the barrier layer is formed between forming the electrochromic or counter electrode layer and forming the first transparent conductive layer, and wherein forming the barrier layer is performed using a metal-silicon compound.