Alternative single-source precursor for growth of indium pnictide thin layers

Abstract

Novel organometallic precursors for the growth of indium pnictide thin layers are reported. Tributylindium, n–Bu₃ln, reacts readily with pnictogen sulfides, As₂S₃, P₂S₅ and Sb₂S₅ to give sulfur-bridged hetero-binuclear organometallics such as [Bu₂ln(SAsBu)₃]₂S (1), [Bu₂lnSP(S)Bu]₂S (2), and [Bu₂lnSSb(S)Bu]₂S (3). They are distillable oils which can be pyrolysed to give the corresponding indium pnictides without sulfur contamination, under an N₂ atmosphere at 500–600 °C. Dip–dry pyrolysis of these complexes on an Si(111) substrate gave high-quality indium pnictide thin films: InAs (µ₃₀₀, 1640 cm² V^–1S^–1; n₃₀₀, 1.3 × 10¹⁴ cm^–3; type, p; T_sub, 600 °C), InP (µ₃₀₀, 1100 cm² V^–1 S^–1; n₃₀₀, 1.2 × 10¹⁹ cm^–3; type, p; T_sub, 600 °C), and InSb (µ₃₀₀, 18 400 cm² V^–1 S^–1; n₃₀₀, 6.8 × 10¹⁶ cm^–3; type, p; T_sub, 450 °C).