摘要 |
On embodiment of a contact structure may include a lower insulation layer on a lower substrate, an upper substrate on the lower insulation layer, a groove penetrating the upper substrate to extend into the lower insulation layer, the groove below an interface between the upper substrate and the lower insulation layer, an upper insulation layer in the groove, and a contact plug penetrating the upper insulation layer in the groove to extend into the lower insulation layer. |