Low pressure chemical vapour deposition of crystalline Ga_2Te_3 and Ga_2Se_3 thin films from single source precursors using telluroether and selenoether complexes

摘要

Neutral telluro- and seleno-ether complexes of the form [GaCl_3(~nBu_2E)] (E = Se, Te) and [(GaCl_3)_2{nBuE(CH_2)nEnBu}] (E = Se, n = 2; E = Te, n = 3) have been synthesised via a facile, high yielding reaction. These complexes have been shown to be suitable precursors for the low pressure chemical vapour deposition of Ga_2Te_3 and Ga_2Se_3, the first reported example of a telluroether complex being used for the deposition of a metal telluride. The thin films have been characterised by X-ray diffraction, SEM, EDX, Raman and Hall measurements. The films are crystalline, have good, uniform coverage and Raman spectra match literature values. Hall measurements show that the thin films are p-type semiconductors. Competitive deposition of Ga_2Te_3 onto photolithographically patterned SiO_2/TiN substrates shows a preference for deposition onto TiN.