Hafnium oxide-based ferroelectric field effect transistor and manufacturing method thereof

A hafnium oxide-based ferroelectric field effect transistor, comprising:

• a substrate (1);
• an isolation region (2) arranged around the substrate (1), wherein an upper surface of the isolation region (2) is not lower than that of the substrate (1), and a bottom surface of the isolation region (2) is not lower than that of the substrate (1);
• a gate structure (3) including a buffer layer (31), a floating gate electrode (32), a hafnium oxide-based ferroelectric film layer (33b), a control gate electrode (34) and a film electrode layer (35) which are sequentially stacked from bottom to top at a middle part of the upper surface of the substrate (1);
• a side wall (4) arranged outside the gate structure (3), wherein an inner surface of the side wall (4) is closely attached to the gate structure (3);
• a source region (5) and a drain region (6) which are oppositely arranged on two sides of the gate structure (3) and are formed by extending from an inner side of the isolation region (2) to the middle part of the substrate (1), wherein upper surfaces of the source region (5) and the drain region (6) are flush with that of the substrate (1), and bottom surfaces of the region (5) and the drain region (6) are not lower than that of the isolation region (2);
• a first metal silicide layer (71) formed by extending from the inner side of the isolation region (2) to the side wall (4), wherein an upper surface of the first metal silicide layer (71) is higher than that of the substrate (1);
• a bottom surface of the first metal silicide layer (71) is higher than that of the isolation region (2);
• and the first metal silicide layer (71) is shorter than the source region (5) or the drain region (6);
• and
• a second metal silicide layer (72) arranged on an upper surface of the gate structure (3), wherein a lower surface of the second metal silicide layer (72) is closely attached to the gate structure (3);
• and
• wherein the floating gate electrode (32) and the control gate electrode (34) are made from HfNx, wherein 0<x≤1.1;
• each of the floating gate electrode (32) and the control gate electrode (34) has a thickness of 5 nm to 50 nm;
• the hafnium oxide-based ferroelectric film layer (33b) has a thickness of 3 nm to 20 nm.