Method for forming a thin film resistor

A method for forming a thin film resistor comprising:

• providing a substrate having a transistor region and a thin film resistor region defined thereon;
• sequentially forming a dielectric layer, a metal layer and a first hard mask layer on the substrate;
• patterning the first hard mask layer to form at least a thin film resistor pattern in the thin film resistor region;
• sequentially forming a polysilicon layer and a second hard mask layer on the metal layer, the first hard mask layer being sandwiched by the metal layer and the polysilicon layer;
• patterning the second hard mask layer to form at least a gate pattern in the transistor region;
• and
• performing an etching process to remove a portion of the polysilicon layer, the metal layer and the dielectric layer to form a gate and a thin film resistor respectively in the transistor region and the thin film resistor region.