Atmospheric-Pressure Chemical Vapor Deposition of Iron Pyrite Thin Films

作者：Berry Nicholas; Cheng Ming; Perkins Craig L; Limpinsel Moritz; Hemminger John C; Law Matt^*

来源：Advanced Energy Materials, 2012, 2(9): 1124-1135.

DOI：10.1002/aenm.201200043

• electro-optical materials
• semiconductors
• solar cells
• thin films
• iron pyrite

Iron pyrite (cubic FeS2) is a promising candidate absorber material for earth-abundant thin-film solar cells. In this report, single-phase, large-grain, and uniform polycrystalline pyrite thin films are fabricated on glass and molybdenum-coated glass substrates by atmospheric-pressure chemical vapor deposition (AP-CVD) using the reaction of iron(III) acetylacetonate and tert-butyl disulfide in argon at 300 degrees C, followed by sulfur annealing at 500-550 degrees C to convert marcasite impurities to pyrite. The pyrite-marcasite phase composition depends strongly on the concentration of sodium in the growth substrate and the sulfur partial pressure during annealing. Phase and elemental composition of the films are characterized by X-ray diffraction, Raman spectroscopy, Auger electron spectroscopy, secondary ion mass spectrometry, Rutherford backscattering spectrometry, and X-ray photoelectron spectroscopy. The in-plane electrical properties are surprisingly insensitive to phase and elemental impurities, with all films showing p-type, thermally activated transport with a small activation energy (30 meV), a room- temperature resistivity of 1 Omega cm, and low mobility. These ubiquitous electrical properties may result from robust surface effects. These CVD pyrite thin films are well suited to fundamental electrical studies and the fabrication of pyrite photovoltaic device stacks.

• 出版日期2012-9