Atomic layer deposition

About: Atomic layer deposition is a research topic. Over the lifetime, 19821 publications have been published within this topic receiving 477332 citations. The topic is also known as: ALD.

Atomic Layer Deposition of Functional Layers for on Chip 3D Li‐Ion All Solid State Microbattery

Abstract: Nowadays, millimeter scale power sources are key devices for providing autonomy to smart, connected, and miniaturized sensors. However, until now, planar solid state microbatteries do not yet exhibit a sufficient surface energy density. In that context, architectured 3D microbatteries appear therefore to be a good solution to improve the material mass loading while keeping small the footprint area. Beside the design itself of the 3D microbaterry, one important technological barrier to address is the conformal deposition of thin films (lithiated or not) on 3D structures. For that purpose, atomic layer deposition (ALD) technology is a powerful technique that enables conformal coatings of thin film on complex substrate. An original, robust, and highly efficient 3D scaffold is proposed to significantly improve the geometrical surface of miniaturized 3D microbattery. Four functional layers composing the 3D lithium ion microbattery stacking has been successfully deposited on simple and double microtubes 3D templates. In depth synchrotron X-ray nanotomography and high angle annular dark field transmission electron microscope analyses are used to study the interface between each layer. For the first time, using ALD, anatase TiO2 negative electrode is coated on 3D tubes with Li3PO4 lithium phosphate as electrolyte, opening the way to all solid-state 3D microbatteries. The surface capacity is significantly increased by the proposed topology (high area enlargement factor – “thick” 3D layer), from 3.5 μA h cm−2 for a planar layer up to 0.37 mA h cm−2 for a 3D thin film (105 times higher).

ZnO grown by atomic layer deposition: A material for transparent electronics and organic heterojunctions

Abstract: We report on zinc oxide thin films grown by atomic layer deposition at a low temperature, which is compatible with a low thermal budget required for some novel electronic devices. By selecting appropriate precursors and process parameters, we were able to obtain films with controllable electrical parameters, from heavily n-type to the resistive ones. Optimization of the growth process together with the low temperature deposition led to ZnO thin films, in which no defect-related photoluminescence bands are observed. Such films show anticorrelation between mobility and free-electron concentration, which indicates that low n electron concentration is a result of lower number of defects rather than the self-compensation effect.

Impact of surface chemical treatment on capacitance-voltage characteristics of GaAs metal-oxide-semiconductor capacitors with Al2 O3 gate dielectric

Abstract: The authors examine the impact of two different chemical surface treatment methods on capacitance-voltage characteristics of GaAs metal-oxide-semiconductor (MOS) capacitors using NH4OH and (NH4)2S prior to atomic layer deposition (ALD) of Al2O3. In both cases, x-ray photoelectron spectroscopy data confirm the removal of As2O3∕As2O6 upon Al2O3 deposition. However, Ga–O bonds appear to incorporate in the final gate stack at the Al2O3∕GaAs interface. MOS capacitors exhibit a steep transition from accumulation to depletion as well as very low leakage current density indicating high quality of ALD-Al2O3. The midgap interface trap density was evaluated to be (∼3–5)×1011∕cm2eV using the Terman method. In addition, quasistatic capacitance-voltage (C-V) measurement confirms the formation of true inversion layer in GaAs using both chemical treatment protocols. However, sulfur-passivated GaAs demonstrates better frequency dispersion behavior and slightly smaller capacitance equivalent thickness than hydroxylated GaA...

Atomic layer deposition of transition metal thin films

Abstract: An atomic layer deposition method for forming metal films on a substrate comprises a deposition cycle including: a) contacting a substrate with a vapor of a metal-containing compound described by formula 1 for a first predetermined pulse time to form a first modified surface: MLn (1) wherein: n is 1 to 8; M is a transition metal; L is a ligand; b) contacting the first modified surface with an acid for a second predetermined pulse time to form a second modified surface; and c) contacting the second modified surface with a reducing agent for a third predetermined pulse time to form a metal layer.

Varied silicon richness silicon nitride formation

Abstract: A method, in one embodiment, can include forming a tunnel oxide layer on a substrate. In addition, the method can include depositing via atomic layer deposition a first layer of silicon nitride over the tunnel oxide layer. Note that the first layer of silicon nitride includes a first silicon richness. The method can also include depositing via atomic layer deposition a second layer of silicon nitride over the first layer of silicon nitride. The second layer of silicon nitride includes a second silicon richness that is different than the first silicon richness.