We have investigated the emission and capture process of native defects in undoped In

0.49

Ga

0.51

P grown by MOCVD using DLTS technique and transient photo-resistivity spectroscopy (TPRS) technique. A common defect with an activation energy of about 0.37eV was observed with DLTS technique. It's found that the capture barriers of the defect distributed over 60meV from 180meV to 240meV by TPRS measurements. The distribution can be interpreted as the microscopic fluctuation of atomic arrangements around the defect. The investigation of capture process seems more powerful then emission process in these materials

because of two defects with capture barrier energy 0.06 and 0.40eV

that can not be detected with DLTS technique

were also observed with TPRS measurements.