Zn‐doped GaxIn1−xP epilayers grown by metalorganic chemical vapor deposition have been studied in a wide range of GaP mole fraction. The Zn distribution coefficient was studied as a function of alloy composition. With a constant flow rate of diethylzinc, a decreasing net hole concentration was observed with increasing GaP mole fraction. TheI‐Vcharacteristics of Au onp‐GaxIn1−xP Schottky diodes show a deviation from an ideal thermionic behavior as the lattice mismatch increases. This deviation was analyzed in terms of the shunt resistance which decreased exponentially with the mismatch. A dominant hole trap located atEV+0.84 eV was detected by deep‐level transient spectroscopy in a Ga0.032In0.968P layer. The density of this hole trap significantly increases with increasing lattice mismatch.