Trench junction field effect transistor having a mesa region

A method for manufacturing a trench junction field effect transistor (trench JFET), the method comprising:

• forming a mesa region confined by first and second trenches along a first lateral direction, the first and second trenches extending into a semiconductor body from a first surface of the semiconductor body,
• wherein forming the mesa region comprises forming, between the first and second trenches, a mesa channel region of a first conductivity type and first and second gate regions of a second conductivity type,
• wherein the mesa channel region is confined, along the first lateral direction, by the first and second gate regions,
• wherein a first pn junction is defined by the mesa channel region and the first gate region,
• wherein a second pn junction is defined by the mesa channel region and the second gate region,
• wherein the mesa channel region includes, along the first lateral direction, first, second and third mesa channel sub-regions having a same extent along the first lateral direction,
• wherein a concentration of dopants of the first conductivity type averaged along the first lateral direction in the second mesa channel sub-region is larger than a concentration of dopants of the first conductivity type averaged along the first lateral direction in each of the first and third mesa channel sub-regions.