The present disclosure provides various embodiments of a via structure and method of manufacturing same. In an example, a via structure includes a via having via sidewall surfaces defined by a semiconductor substrate. The via sidewall surfaces have a first portion and a second portion. A conductive layer is disposed in the via on the first portion of the via sidewall surfaces, and a dielectric layer is disposed on the second portion of the via sidewall surfaces. The dielectric layer is disposed between the second portion of the via sidewall surfaces and the conductive layer. In an example, the dielectric layer is an oxide layer.