Philip Anish, Mai Lukas, Ghiyasi Ramin, Devi Anjana, Karppinen Maarit
Department of Chemistry and Materials Science, Aalto University, FI-00076 Espoo, Finland.
Inorganic Materials Chemistry, Ruhr University Bochum, 44801 Bochum, Germany.
Dalton Trans. 2022 Oct 4;51(38):14508-14516. doi: 10.1039/d2dt02279f.
The combined atomic/molecular layer deposition (ALD/MLD) technique is emerging as a state-of-the-art synthesis route for new metal-organic thin-film materials with a multitude of properties by combining those of the inorganic and the organic material. A major part of the studies so far reported have focused on aluminum or zinc alkyls, so-called alucone and zincone films, typically grown from trimethyl aluminum (TMA) or diethyl zinc (DEZ) as the metal-bearing precursor, and a simple aliphatic bi-functional alcohol molecule such as ethylene glycol (EG) as the organic precursor. However, these common precursors possess certain disadvantages: both TMA and DEZ are pyrophoric, DEZ being additionally thermally unstable, while EG has a strong tendency for various unideal reaction modes. Here we report novel ALD/MLD processes for alucone and zincone films based on non-pyrophoric bis-diisopropylamido-[3-(,-dimethylamino)propyl] aluminum(III) [Al(NiPr)(DMP)] and bis-3-(,-dimethylamino)propyl zinc(II) [Zn(DMP)] precursors in combination with hydroquinone (HQ) as the organic precursor. We demonstrate that the [Al(NiPr)(DMP)] + HQ and [Zn(DMP)] + HQ ALD/MLD processes work even at record low deposition temperatures (140 °C and 60 °C, respectively) yielding high-quality and relatively stable Al-HQ and Zn-HQ thin films with appreciably high growth rates (2.8 Å / cycle and 3.2 Å / cycle, respectively). Moreover, these ALD/MLD processes are compatible with the corresponding ALD processes, [Al(NiPr)(DMP)] + HO and [Zn(DMP)] + HO, for the AlO and ZnO films, thus opening up new horizons for the fabrication of novel metal-oxide : organic superlattice structures for flexible gas-barrier coatings or wearable thermoelectrics.
原子/分子层沉积（ALD/MLD）相结合的技术正在成为一种先进的合成路线，用于制备具有多种特性的新型金属有机薄膜材料，它将无机材料和有机材料的特性结合在一起。目前报道的大部分研究都集中在烷基铝或烷基锌上，即所谓的铝酮和锌酮薄膜，通常由三甲基铝（TMA）或二乙基锌（DEZ）作为含金属前驱体生长而成，以及一种简单的脂肪族双功能醇分子，如乙二醇（EG）作为有机前驱体。然而，这些常见的前驱体存在一定的缺点：TMA和DEZ都具有自燃性，DEZ还具有热不稳定的特性，而EG有强烈的各种不理想反应模式的倾向。在此，我们报道了基于非自燃性的双二异丙基氨基-[3-(N,N-二甲基氨基)丙基]铝(III) [Al(NiPr)(DMP)]和双-3-(N,N-二甲基氨基)丙基锌(II) [Zn(DMP)]前驱体与对苯二酚（HQ）作为有机前驱体的铝酮和锌酮薄膜的新型ALD/MLD工艺。我们证明，[Al(NiPr)(DMP)] + HQ和[Zn(DMP)] + HQ的ALD/MLD工艺即使在创纪录的低温（分别为140°C和60°C）下也能起作用，可得到高质量且相对稳定的Al-HQ和Zn-HQ薄膜，且生长速率相当高（分别为2.8 Å/循环和3.2 Å/循环）。此外，这些ALD/MLD工艺与用于AlO和ZnO薄膜的相应ALD工艺[Al(NiPr)(DMP)] + HO和[Zn(DMP)] + HO兼容，从而为制造用于柔性气体阻隔涂层或可穿戴热电器件的新型金属氧化物：有机超晶格结构开辟了新的前景。
