Method of producing ferroelectric capacitor

A method of producing a ferroelectric capacitor, comprising the steps of:

• preparing a semiconductor substrate with MOSFETs having impurity diffused areas, said MOSFETs being formed on the semiconductor substrate in a memory cell area and a peripheral circuit area outside the memory cell area, respectively;
• forming a first interlayer insulating film on the semiconductor substrate;
• forming a conductive plug in the first interlayer insulating film to be electrically connected to the impurity diffused areas of the MOSFETs;
• forming a process protection film on on the first interlayer insulating film forming a second interlayer insulating film on the process protection film;
• removing a portion of the second interlayer insulating film in the memory cell area to expose a surface of the process protection film while remaining other portion of the second interlayer insulating film in the peripheral circuit area;
• removing the exposed surface of the process protection film to expose a surface of the first interlayer insulating film and a top of the conductive plug;
• laminating a first conductive layer, a ferroelectric layer, and a second conductive layer sequentially on the exposed surface of the first interlayer insulating film and an exposed surface of the other portion of the second interlayer insulating film to form a capacitor forming laminated film;
• forming an etching mask on the capacitor forming laminated film in a capacitor forming area defined on the conductive plug included in the memory cell area;
• and
• etching the capacitor forming laminated film with the etching mask to form a ferroelectric capacitor.