Field-effect transistor and corresponding manufacturing method
AssigneeSTMicroelectronics S.r.l.
InventorsFederico Pio, Paola Zuliani
Life of this patent
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Abstract
A field effect transistor having a variable doping profile is presented. The field effect transistor is integrated on a semiconductor substrate with a respective active area of the substrate including a source and drain region. A channel region is interposed between the source and drain regions and has a predefined nominal width. The effective width of the channel region is defined by a variable doping profile.
Claims8
A method for manufacturing a field effect transistor integrated onto a semiconductor substrate with an active area having a nominal width, the field effect transistor including a source region and a drain region formed in said semiconductor substrate, and a channel region interposed between said source and drain regions and having a nominal width in a first direction that is perpendicular to a second direction that extends through the source, drain, and channel regions, the method comprising:
- forming said active area in the semiconductor substrate,
- masking said active area with a mask of greater width in the first direction than the nominal width of the active area;
- implanting a dopant in the substrate around the mask in the first direction in such a way that the channel region has an effective width defined by a variable doping profile in the first direction.
A method for manufacturing a field effect transistor integrated onto a semiconductor substrate with a respective active area in the substrate having a nominal width, the field effect transistor including a source region and a drain region formed in the active area, and the substrate having a channel region of nominal width interposed between the source and drain regions, the method comprising:
- forming the active area in the substrate;
- masking the active area with a mask of that has a greater width than the nominal width of the active area;
- implanting dopants in the substrate through the mask and into a region of the substrate adjacent to the channel region;
- and
- thermally treating the substrate in such a way that the dopants diffuse into the channel region, wherein the channel region of the transistor thereby has an effective width formed by a variable doping profile.
Dependencies are inferred from the claim text.