Volatile Amidoalane Compounds for Chemical Vapor Deposition of Aluminum

Abstract

H2Al{N(Et)C2H4NMe2} (DMEEDA), H2Al{N(Me)C2H4NMe2} (TRMEDA), and H2Al{N(Et)C2H4NEt2} (TREEDA) were synthesized and proposed as new precursors for the deposition of Al films. These amidoalane complexes are thermally stable and isolated as volatile liquids or low-melting solids. The thermal stability of these complexes was so high that no thermal decomposition was detected from the gas-phase IR spectra, even at 220 °C. They deposit high-purity Al films on TiN substrates at temperatures as low as 70 °C, while no deposition was observed on SiO2 at 250 °C. A SEM image shows remarkably smooth surface morphology of the Al film deposited on a patterned TiN/Si wafer using DMEEDA.

Versatile Ln2(μ-NR)2-Imide Platforms for Ligand Exchange and Isoprene Polymerization

“… , Usually the synthesis of imidoalanes requires prolonged thermal treatment of AlMe 3 with H 2 NR . The most important application of amidoalanes and imidoalanes is their use as precursors for chemical vapor deposition (CVD) for the production of semiconducting microelectronic devices …”

Atomic Layer Deposition of Aluminum Metal Films Using a Thermally Stable Aluminum Hydride Reducing Agent

“…Careful ligand design is the primary tool for preparing stabilized main group hydrides. − Volatile dimeric Al dihydride complexes coordinated by simple amido-amine ligands of the formula (RN)­CH 2 CH 2 (NMe 2 ) (R = Me, Et) have been reported. , These dimeric Al dihydride complexes have been reported as CVD precursors to Al metal films at temperatures as low as 70 °C and are thus insufficiently thermally stable for ALD . We envisioned a tert -butyl-substituted amido-amine ligand that could produce monomeric Al dihydride complexes with high thermal stability based on (1) the chelate effect, (2) a saturated carbon backbone, thereby preventing reduction of the ligand by Al–H, and (3) the steric bulk and strong electron donating ability of the tert -butylamido group (Scheme ).…”

“…40,41 These dimeric Al dihydride complexes have been reported as CVD precursors to Al metal films at temperatures as low as 70 °C and are thus insufficiently thermally stable for ALD. 42 We envisioned a tert-butylsubstituted amido-amine ligand that could produce monomeric Al dihydride complexes with high thermal stability based on (1) the chelate effect, (2) a saturated carbon backbone, thereby preventing reduction of the ligand by Al−H, and (3) the steric bulk and strong electron donating ability of the tert-butylamido group (Scheme 1). Complex 1 was synthesized in 71% yield from 1-(tert-butylamino)-2-dimethylaminoethane and Al-H 3 (OEt 2 ) x and was found to exhibit high volatility and good thermal stability.…”

Hydrido and chloro gallium and aluminium complexes with the tridentate bis(2-dimethylaminoethyl)amide ligand

“…Aluminium and gallium hydride derivatives are alternative precursors to metal trialkyls in chemical vapor deposition (CVD) applications. 1,2 Low-temperature Al metallization has been achieved using aluminium hydride amine adducts such as H 3 Al(NMe 3 ) and H 3 Al(NMe 2 Et) and alkyl aluminium hydrides such as (CH 3 ) 2 AlH. 1 CVD using a chelating amidoamine stabilizing aluminium hydride, H 2 Al[N(Et)CH 2 CH 2 NMe 2 ], achieved comparable results with an advantage of improved precursor thermal stability.…”

“…1 CVD using a chelating amidoamine stabilizing aluminium hydride, H 2 Al[N(Et)CH 2 CH 2 NMe 2 ], achieved comparable results with an advantage of improved precursor thermal stability. 3 In the case of gallium, useful hydridebased precursors remain to be discovered. Known stable gallium hydride derivatives usually contain bulky ligands such as [2,6-(Me 2 NCH 2 ) 2 C 6 H 3 )]GaH 2 4 and H 2 Ga[N(SiMe 3 ) 2 ](quinuclidine), 5 or they form oligomers as found in [H 2 GaNMe 2 ] 3 6 and [ t Bu(H)GaNEt 2 ] 2 .…”