Cesium iodide (CsI) is a well-established scintillator material that also serves as a precursor for all-inorganic halide perovskite solar absorbers, such as CsPbI 3 . However, the lack of conformal and scalable methods to deposit halide perovskite thin films remains a major challenge on their way to commercialization. In this work, we employ atomic layer deposition (ALD) as the key method due to its inherent scalability to large areas and complex-shaped surfaces. We demonstrate two new ALD processes for the deposition of CsI and CsPbI 3 thin films. The CsI process relies on cesium bis(trimethylsilyl) amide (Cs(btsa)) and tin(IV) iodide (SnI 4 ) as precursors and yields high-purity, uniform, and phase-pure thin films. This process works in a wide temperature range (140−350 °C) and exhibits a large growth per cycle value (GPC) of 3.3 Å (85% of a CsI monolayer). Furthermore, we convert CsI into CsPbI 3 perovskite by exposing a CsI film to our earlier PbI 2 ALD process. We demonstrate the deposition of phase-pure γor δ-CsPbI 3 perovskite thin films, depending on the applied deposition temperature and number of PbI 2 cycles. We believe that the ALD-based approach described in this work will offer a viable alternative for depositing perovskite thin films in applications that involve complex high aspect ratio structures or large substrate areas.

This work presents preparation of nickel germanide (Ni 2 Ge) thin films by atomic layer deposition (ALD). The films were grown using NiCl 2 (tmpda) (tmpda = N,N,N′,N′,-tetramethyl-1,3-propanediamine) and tributylgermanium hydride serving as a new, efficient reducing agent. This is the first time ALD Ni x Ge y films are prepared directly upon the combination of two precursors and without any annealing treatment. Ni x Ge y is an important contact material for enabling Ge-based transistors and thus circumventing the scaling issues related to current microelectronics. The Ni 2 Ge process was examined at low temperatures of 160−200 °C. Self-limiting, saturative growth with a high growth rate of 0.91 Å/cycle was observed at 180 °C. The films were thoroughly analyzed in terms of morphology, crystallinity, composition, and resistivity. The Ni 2 Ge films were pure, with the sum of contaminants being less than 1 at. %. Owing to their high purity, the films exhibited low resistivity, suggesting suitability for contact applications.

In this work, we developed a new ALD process for nickel metal from dichlorobis(triethylphosphine)nickel(II) (NiCl2(PEt3)2) and 1,4-bis(trimethylgermyl)-1,4-dihydropyrazine ((Me3Ge)2DHP). A series of phosphine adducts of nickel and cobalt halides was synthesized...

In this work, we developed an atomic layer deposition (ALD) process for gold metal thin films from chloro(triethylphosphine)gold(I) [AuCl(PEt 3 )] and 1,4-bis(trimethylgermyl)-1,4-dihydropyrazine [(Me 3 Ge) 2 DHP]. High purity gold films were deposited on different substrate materials at 180 °C for the first time with thermal reductive ALD. The growth rate is 1.7 Å/cycle after the film reaches full coverage. The films have a very low resistivity close to the bulk value, and a minimal amount of impurities could be detected. The reaction mechanism of the process is studied in situ with a quartz crystal microbalance and a quadrupole mass spectrometer.

This paper presents preparation of boron‐doped Al2O3 thin films by atomic layer deposition (ALD) using phenylboronic acid (PBA) and trimethylaluminum (TMA) as precursors. Deposition temperatures of 160–300 °C are studied, giving a maximum growth per cycle (GPC) of 0.77 Å at 200 °C. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) are used to study the surface morphology and roughness of the films. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR), Time‐of‐flight elastic recoil detection analysis (ToF‐ERDA), and X‐ray photoelectron spectroscopy (XPS) are used to study the composition of the films. An annealing process is carried out at 450 °C for 1 h to investigate its effect on the elemental composition and electrical properties of the boron‐doped Al2O3 thin films. The boron‐doped Al2O3 70 nm thick film deposited at 200 °C has a boron content of 3.7 at.% with low leakage current density (10−9 to 10−6 A cm−2) when the film thickness is 70 nm. The dielectric constant of this boron doped Al2O3 film is 5.18.