In this letter, a high-current self-aligned raised source/drain polycrystalline silicon thin-film transistor (HCSARSD-TFT) is proposed and demonstrated for the first time. This new self-aligned device features two channels, i.e., a nitride spacer offset-gated structure and a raised source/drain (RSD) region, that reveal better device performance. Our experimental results show that the ON-current of the HCSARSD-TFT is about two times higher than that of the conventional structure, and the leakage current is considerably reduced simultaneously. In addition, since the gate and RSD areas of the proposed device are self-aligned, no extra mask is needed when comparing it with conventional coplanar RSD TFTs.