An electrochromic structure (100, 400), comprising: a substrate (101, 410) including thermally semi-tempered glass having a surface stress of 30 MPa to 60 MPa; a first filament (102, 402) in the substrate (101, 410) extending in a direction substantially parallel to a thickness of the substrate; an electrochromic stack on the substrate, wherein the electrochromic stack comprises: a first transparent conductive layer including a first portion and a second portion spaced apart from the first portion; and a first electrode layer disposed over the first portion and the second portion of the transparent conductive layer; a second electrode layer disposed over the first electrode layer, wherein one of the first and second electrode layers (124, 128) is an electrochromic layer and the other one is an ion storage layer; a first bus bar disposed on the first portion of the transparent conductive layer and electrically connected to the first electrode layer via the first transparent conductive layer; a second bus bar disposed on the second portion of the transparent conductive layer and electrically connected to the second electrode layer via a second transparent conductive layer disposed over the second electrode layer; and an electrochromic residue on the substrate, wherein each of the transparent conductive layers (122, 130) include portions removed, so that the first and second bus bars (144, 148) are not electronically connected to each other, and wherein the electrochromic residue comprises a composition of a layer or a combination of the layers of the electrochromic stack and is spaced apart from the electrochromic stack by a distance, the electrochromic structure (100, 400) further comprising a filament pattern comprising a plurality of filaments (102, 402) including the first filament (102, 402), each filament (102, 402) extending in a direction substantially parallel to the thickness of the substrate, wherein the filament pattern comprises a curvature having a radius of at most 5 μm. a substrate (101, 410) including thermally semi-tempered glass having a surface stress of 30 MPa to 60 MPa; a first filament (102, 402) in the substrate (101, 410) extending in a direction substantially parallel to a thickness of the substrate; an electrochromic stack on the substrate, wherein the electrochromic stack comprises: a first transparent conductive layer including a first portion and a second portion spaced apart from the first portion; and a first electrode layer disposed over the first portion and the second portion of the transparent conductive layer; a first transparent conductive layer including a first portion and a second portion spaced apart from the first portion; and a first electrode layer disposed over the first portion and the second portion of the transparent conductive layer; a second electrode layer disposed over the first electrode layer, wherein one of the first and second electrode layers (124, 128) is an electrochromic layer and the other one is an ion storage layer; a first bus bar disposed on the first portion of the transparent conductive layer and electrically connected to the first electrode layer via the first transparent conductive layer; a second bus bar disposed on the second portion of the transparent conductive layer and electrically connected to the second electrode layer via a second transparent conductive layer disposed over the second electrode layer; and wherein one of the first and second electrode layers (124, 128) is an electrochromic layer and the other one is an ion storage layer; a first bus bar disposed on the first portion of the transparent conductive layer and electrically connected to the first electrode layer via the first transparent conductive layer; a second bus bar disposed on the second portion of the transparent conductive layer and electrically connected to the second electrode layer via a second transparent conductive layer disposed over the second electrode layer; and an electrochromic residue on the substrate, wherein each of the transparent conductive layers (122, 130) include portions removed, so that the first and second bus bars (144, 148) are not electronically connected to each other, and wherein the electrochromic residue comprises a composition of a layer or a combination of the layers of the electrochromic stack and is spaced apart from the electrochromic stack by a distance, the electrochromic structure (100, 400) further comprising a filament pattern comprising a plurality of filaments (102, 402) including the first filament (102, 402), each filament (102, 402) extending in a direction substantially parallel to the thickness of the substrate, wherein the filament pattern comprises a curvature having a radius of at most 5 μm.