Ruthenium: A superior compensator of InP

Abstract
The 4d-transition metal ruthenium presents a new dopant to fabricate thermally stable semi-insulating InP layers for both electron and hole injection. The layers are grown by low-pressure metalorganic chemical vapor deposition using tertiarybutylphosphine and trimethylindium as source materials for InP growth. Using bis(η5-2,4-dimethyl-pentadienyl)ruthenium(II) as precursor Ru doping concentrations of the order of 4×1018 cm−3 are achieved, determined by means of secondary ion mass spectroscopy. The Ru diffusion coefficient in InP is determined to DRu(800 °C)⩽1×10−15 cm2/s which is four orders of magnitude smaller than for Fe. Resistivities obtained under electron and hole injection are above 6×107 Ω cm and 5×108 Ω cm, respectively. In deep level transient spectroscopy measurements under electron emission and hole emission, one deep level each with concentrations around 1016 cm−3, is observed.