A thinned integrated circuit device and manufacturing process for the same are disclosed. The manufacturing process includes forming a through-silicon via (TSV) on a substrate, a first terminal of the TSV is exposed on a first surface of the substrate, disposing a bump on the first surface of the substrate to make the bump electrically connected with the TSV, disposing an integrated circuit chip (IC) on the bump so that a first side of the IC is connected to the bump, disposing a thermal interface material (TIM) layer on a second side of the IC opposite to the first side of the IC, attaching a heat-spreader cap on the IC by the TIM layer, and backgrinding a second surface of the substrate to expose the TSV to the second surface of the substrate while carrying the heat-spreader cap.