The present invention discloses a method for self-alignedly fabricating tunneling field-effect
transistor (TFET) based on
planar process, thereby lowering requirements on a
photolithography process for fabricating the planar TFET. In the method, the source region and the drain region of the TFET are not directly defined by
photolithography; rather, they are defined by another
dielectric film which locates over an active region and on both sides of the gate and which is different from the
dielectric film that defines the channel region. The influence due to the alignment deviation among three times of
photolithography process for defining the channel region, the source and the drain regions may be eliminated by selectively removing the
dielectric film over the source and drain regions by wet
etching. Therefore, a planar TFET may be fabricated self-alignedly based on this process, thereby the rigid requirements on the alignment deviation of the photolithography during the fabrication procedure of a planar TFET is alleviated, which facilitates to fabricate a planar TFET device with stable and reliable characteristics.