Solid-phase epitaxial Pd/Ge ohmic contacts to In1-xGaxAsyP1-y/InP

A Pd/Ge metallization to InGaAsP/InP semiconductors, formed with solid-phase epitaxy (SPE) technique, has been investigated in this study. With this method, ohmic contacts with low specific contact resistance (
\rho_{c} \approx 2.3 \times 10^{-6}
Ω.cm
²
) have been achieved on p-type In
0.53
Ga
0.47
As(
p \approx 1.8 \times 10^{19}
/cm
³
). The same contact scheme also gives low specific contact resistance (
\rho_{c} \approx 6 \times 10^{-7}
Ω.cm
²
) on n-type In
0.53
Ga
0.47
As (
n \approx 1.0 \times 10^{19}
/cm
³
). Excellent surface morphology is observed in all the samples, and the contacts do not deteriorate for at least 4 h at temperatures between 300 and 500°C.