A system, method and device for measuring a depth of a Through-Silicon-Via (TSV) in a semiconductor device region on a wafer during in-line semiconductor fabrication, includes a resistance measurement trench structure having length and width dimensions in a substrate, ohmic contacts on a surface of the substrate disposed on opposite sides of the resistance measurement trench structure, and an unfilled TSV structure in semiconductor device region having an unknown depth. A testing circuit makes contact with the ohmic contacts and measures a resistance therebetween, and a processor connected to the testing circuit calculates a depth of the trench structure and the unfilled TSV structure based on the resistance measurement. The resistance measurement trench structure and the unfilled TSV are created simultaneously during fabrication.