Growth and characterization of close-spaced sublimation zinc phosphide thin films

Zinc phosphide (Zn₃P₂) thin films (~10 μm) have been grown by close-spaced sublimation. The electrical, optical, and crystallographic properties of the synthesized Zn₃P₂ are measured. The as-grown films exhibit hole carrier concentrations of about 10¹⁶ holes/cm³, resistivity on the order of 10² Ohm·cm, and large grain size (1-10 μm), making them promising for thin-film solar cell applications. We find that while exposure to atmosphere is detrimental to the electrical properties, annealing films above 350°C, especially in oxygen ambient, drastically reverses these effects.