A tunneling field-effect transistor (TFET) device is disclosed. The TFET device includes a source contact on the source region, a plurality of gate contacts at a planar portion of a gate stack and a plurality of drain contacts disposed on a drain region. The source contact of the TFET device aligns with other two adjacent source contacts of other two TFET devices such that each source contact locates in one of three angles of an equilateral triangle.