Disclosed are embodiments of a Schottky barrier diode. This diode can be formed in a semiconductor substrate having a doped region with a first conductivity type. A trench isolation structure can laterally surround a section of the doped region at the top surface of the substrate. A semiconductor layer can be positioned on the top surface of the substrate. This semiconductor layer can have a Schottky barrier portion over the defined section of the doped region and a guardring portion over the trench isolation structure laterally surrounding the Schottky barrier portion. The Schottky barrier portion can have the first conductivity type and the guarding portion can have a second conductivity type different from the first conductivity type. A metal silicide layer can overlie the semiconductor layer. Also disclosed are embodiments of a method of forming this Schottky barrier diode and of a design structure for the Schottky barrier diode.