Deep levels in GaP

Abstract
Change of the junction capacitance under the illumination of monochromatic radiation has been observed in GaP n+p junctions. The peaks were observed at 1.8 and 2.4 eV at 77°K. The 1.8 eV peak was attributed to the hole activation from Fe3+ to the valence band. The photoconductivity spectrum and the transient phenomenon of the photoconductivity in p+n junctions and in high‐resistivity n‐type bulk crystals also showed the presence of the 1.8 eV level due to Fe.