| 摘要 |
A method of manufacturing a semiconductor device comprising a non-volatile memory FET, wherein an active region (4) of a first conductivity type is defined at a surface (2) of a semiconductor body (1), and a patterned layer (6, 7) is formed on said active region (4), which patterned layer is a dummy gate that acts as a mask during the formation of a source zone (11) and a drain zone (12) of a second conductivity type in the semiconductor body (1). Then, a dielectric layer (14) is provided in a thickness which is sufficiently large to cover the patterned layer, which dielectric layer (14) is removed over part of its thickness by means of a material removing treatment such as CMP until the patterned layer is exposed. In a next step, the patterned layer is removed, thereby forming a recess (15) in the dielectric layer (14). In this recess a first insulating layer (18) is applied providing a floating gate dielectric (19), to which first insulating layer a first conductive layer (20) is applied filling the recess in the dielectric layer (14), which first conductive layer is shaped into a floating gate (21) by means of masked etching. The floating gate (21) has a T-shape with a substantially flat surface portion (22) extending substantially parallel to the surface (2) of the semiconductor body (1) and sidewall portions (23) extending substantially perpendicularly to the surface (2) of the semiconductor body (1). In a next step, the floating gate (21) is covered by a second insulating layer (24) providing an inter-gate dielectric (25), to which second insulating layer a second conductive layer (26) is applied, which is shaped into an overlapping control gate (27). The control gate (27) is capacitively coupled with the substantially flat surface portion (22) of the floating gate (21) and with at least the sidewall portions (23) of the floating gate (21) situated adjacent to the source zone (11) and the drain zone (12) of the memory FET. |
