ⁿBu₂Sn(SⁿBu)₂ and ⁿBu₃SnEⁿBu (E = S or Se) – effective single source precursors for the CVD of SnS and SnSe thermoelectric thin films

Abstract

The use of single source precursors offers a convenient option for the chemical vapour deposition of thin film semiconductor materials with good stoichiometric control and precursor efficiency. Here we show...

Low-Pressure CVD of GeE (E = Te, Se, S) Thin Films from Alkylgermanium Chalcogenolate Precursors and Effect of Deposition Temperature on the Thermoelectric Performance of GeTe

“…The target compounds (1)− (4) were isolated in very good yields as mobile oils using slight modifications of the methods developed for [Bu 3 Sn(EBu)] (E = Te, Se, S), which we have shown to be effective precursors for the LPCVD growth of SnE thin films. 38,39 The synthesis of the selenolate and tellurolate precursors (1)−(3) requires a different synthetic route from that of (4). For the latter, a range of thiols are widely available commercially and simple deprotonation and salt elimination, as illustrated in Scheme 1 (bottom), yield the target thiolate precursor (4).…”

“…The germanium­(IV) precursors ( 1 )–( 4 ) (Scheme ) were identified as potential candidates for the growth of the germanium monochalcogenides, GeE (E = Te, Se, S), as they incorporate direct bonds between the Ge and E atoms, have sufficient volatility to allow vaporization in the CVD reactor, and contain n -butyl groups that can readily undergo elimination reactions, leading to clean deposition of the target binary semiconductor. The target compounds ( 1 )–( 4 ) were isolated in very good yields as mobile oils using slight modifications of the methods developed for [Bu 3 Sn­(EBu)] (E = Te, Se, S), which we have shown to be effective precursors for the LPCVD growth of SnE thin films. , The synthesis of the selenolate and tellurolate precursors ( 1 )–( 3 ) requires a different synthetic route from that of ( 4 ). For the latter, a range of thiols are widely available commercially and simple deprotonation and salt elimination, as illustrated in Scheme (bottom), yield the target thiolate precursor ( 4 ).…”

Template-Mediated Formation of Colloidal Two-Dimensional Tin Telluride Nanosheets and the Role of the Ligands

“…Low-dimensional thermoelectric materials such as tin telluride (SnTe) can adopt advantages based on the quantum confinement effect, suggesting great potential for heat-electricity conversion. 1 As a IV-VI narrow bandgap semiconductor (0.18 eV, bulk), SnTe exhibits an intrinsically high charge carrier concentration, which results in a relatively low Seebeck coefficient, 2,3 but optimization of the material through doping and alloying offers great promise for thermoelectric applications of this material. 2 SnTe has also gained significant interest due to its exciting properties as a topological crystalline insulator, IR detection and radiation receivers material, as well as photovoltaic absorber.…”

“…1 As a IV-VI narrow bandgap semiconductor (0.18 eV, bulk), SnTe exhibits an intrinsically high charge carrier concentration, which results in a relatively low Seebeck coefficient, 2,3 but optimization of the material through doping and alloying offers great promise for thermoelectric applications of this material. 2 SnTe has also gained significant interest due to its exciting properties as a topological crystalline insulator, IR detection and radiation receivers material, as well as photovoltaic absorber. [4][5][6][7][8] So far, attempts to obtain solution-based SnTe nanocrystals (NCs) mainly yielded zero-dimensional (0D) or one-dimensional (1D) nanostructures.…”

Vapor Phase Synthesis of SnS Facilitated by Ligand-Driven “Launch Vehicle” Effect in Tin Precursors

“…The tin(II) dithiolate [Sn(SCH 2 CH 2 CH 2 S) 2 ] has been used for phase-pure SnS deposition, obtained in MOCVD at temperatures between 300 and 400 • C [23]. The alkyltin chalcogenolate precursors [SnBu n 2 (SBu n ) 2 ] and [SnBu n 3 (SBu n )] were employed in low pressure (LP)-MOCVD for the deposition of phase pure SnS in the temperature range between 375 and 530 • C [24]. Aerosolassisted chemical vapor deposition (AACVD) of tin(II) thioamidates [25], tin(II) thioureide, tin(II) dithiocarbamates [Sn(S 2 CNRR ' ) 2 ] (R,R ' = alkyl) [26], tin(IV) dialkyldithiocarbamates [Sn(C 4 H 9 )(S 2 CNRR ' ) 2 ], [Sn(C 6 H 9 )(S 2 CNRR ' ) 2 ] [27] and heteroleptic tribenzyltin(IV) thiosemicarbazones Bz 3 SnCl(L) (L = thiosemicarbazone) [28] resulted in temperaturedependent polymorphs of SnS [29,30].…”