Patent ID: 8604540

Claim:
A semiconductor device having a junction field-effect transistor (JFET) comprising: a semiconductor substrate having a main surface; a first conductivity type semiconductor layer epitaxially grown on the main surface of the substrate, the first conductivity type semiconductor layer having a back surface opposite to the main surface; a recess having a bottom defined by the main surface of the substrate and a side wall defined by the semiconductor layer, a depth of the recess equaling a thickness of the semiconductor layer in a direction from the main surface to the back surface, and the recess dividing the semiconductor layer into a source region and a drain region; a first conductivity type channel layer epitaxially grown on the bottom and the side wall of the recess, the channel layer having an impurity concentration lower than an impurity concentration of the semiconductor layer; a second conductivity type gate region epitaxially grown on a surface of the channel layer, the gate region spaced by the channel layer from the source region and the drain region; a gate electrode electrically connected to the gate region; a source electrode electrically connected to the source region; and a drain electrode electrically connected to the drain region.