Aspects of the present disclosure are related to a semiconductor device that includes a crystalline substrate having a first surface and a second surface vertically opposite each other and an insulating layer disposed on the first surface of the crystalline substrate. The device may also include an etch stop layer interposed between and contacting the crystalline substrate and the insulating layer and a conductive through via structure penetrating the crystalline substrate and the insulating layer. The device may also include an insulating separation layer disposed horizontally adjacent to the conductive through via structure, and having an inner wall and an outer wall. The insulating separation layer may include a first portion disposed between the conductive through via structure and the crystalline substrate, and a second portion disposed between the conductive through via structure and the etch stop layer.