GaP was grown by metal-organic vapour phase epitaxy (MOVPE) technique under different phosphorous pressure. The deep levels produced under different growth conditions were investigated and the natvres of the deep levels were recognized by the aid of combination of luminescence and jurction techniques.During the MOVPE growth process

the Ga flow was kept unchanged between different runs to ensure a constant growth rate (0.1μm/min)

but the P mole fraction (mf) varied for different runs ranging from 0.97 to 6.2×10

-3

mf to form different nonstoichiometry. The grown layers had carrier concentrations of 0.9-6×10

16

cm

-3

as deduced from

C-V

measurements on Cr evaporated Schottky barriers.

p

+

n

diodes were produced by Zn diffusion.