Improved Al/InP Schottky barriers by coimplantation of Be/P

The development of conventional InP MESFET technology is strongly hampered by the low barrier height (0.3-0.4eV) obtained in InP, due to surface Fermi level pinning, and consequent high reverse leakage currents. As a result, several techniques are being applied to increase the Schottky barrier height on n-InP. The authors present a technique for obtaining improved Al/InP Schottky barriers on n-InP by using coimplantation of Be/P. Schottky barrier heights as high as 0.64 eV have been obtained, along with an ideality factor very close to unity. The reverse leakage current density is also reduced by almost four orders of magnitude.<>