The present invention relates to a through-wafer via device (10) comprising a wafer (12) made of a wafer material and having a first wafer surface (12a) and a second wafer surface (12b) opposing the first wafer surface (12a). The through-wafer via device (10) further comprises a plurality of side by side first trenches (14) provided with a conductive material and extending from the first wafer surface (12a) into the wafer (12) such that a plurality of spacers (16) of the wafer material are formed between the first trenches (14). The through-wafer via device (10) further comprises a second trench (18) provided with the conductive material and extending from the second wafer surface (12b) into the wafer (12), the second trench (18) being connected to the first trenches (14). The through-wafer via device (10) further comprises a conductive layer (20) made of the conductive material and formed on the side of the first wafer surface (12a), the conductive material filling the first trenches (14) such that the first conductive layer (20) has a substantially planar and closed surface.