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.

Surface Chemistry and Electrical Properties of Germanium Nanowires

Abstract: Germanium nanowires with p- and n-dopants were synthesized by chemical vapor deposition and used to construct complementary field effect transistors . Electrical transport and x-ray photoelectron spectroscopy data are correlated to glean the effects of Ge surface chemistry to the electrical characteristics of GeNWs. Large hysteresis due to water molecules strongly bound to GeO2 on GeNWs is revealed. Different oxidation behavior and hysteresis characteristics and opposite band bending due to Fermi level pinning by interface states between Ge and surface oxides are observed for p- and n-type GeNWs. Vacuum annealing above 400C is used to remove surface oxides and eliminate hysteresis in GeNW FETs. High-k dielectric HfO2 films grown on clean GeNW surfaces by atomic layer deposition (ALD) using an alkylamide precursor is effective serving as the first layer of surface passivation. Lastly, the depletion length along the radial direction of nanowires is evaluated. The result suggests that surface effects could be dominant over the bulk properties of small diameter wires.

Improved Cycle Life and Stability of Lithium Metal Anodes through Ultrathin Atomic Layer Deposition Surface Treatments

Abstract: Improving the cycle life and failure resistance of lithium metal anodes is critical for next-generation rechargeable batteries. Here, we show that treating Li metal foil electrodes with ultrathin (∼2 nm) Al2O3 layers using atomic layer deposition (ALD) without air exposure can prevent dendrite formation upon cycling at a current density of 1 mA/cm2. This has the effect of doubling the lifetime of the anode before failure both under galvanostatic deep discharge conditions and cyclic plating/stripping of symmetric Li–Li cells. The ALD treated electrodes can be cycled for 1259 cycles before failure occurs, which is attributed to improved electrode morphology resulting from homogeneous Li ion flux across the electrode/electrolyte interface.

Conformal Al2O3 dielectric layer deposited by atomic layer deposition for graphene-based nanoelectronics

Abstract: We present a facile route which combines the functionalization of a highly oriented pyrolytic graphite surface with an atomic layer deposition (ALD) process to allow for conformal Al2O3 layers. While the trimethylaluminum (TMA)∕H2O process caused selective deposition only along step edges, the TMA∕O3 process began to provide nucleation sites on the basal planes of the surface. O3 pretreatment, immediately followed by the ALD process with TMA∕O3 chemistry, formed Al2O3 layers without any preferential deposition at the step edges. This is attributed to functionalization of graphene by ozone treatment, imparting a hydrophilic character which is desirable for ALD deposition.

Atomic layer deposition for fabricating thin films

Abstract: An atomic layer deposition (ALD) process deposits thin films for microelectronic structures, such as advanced gap and tunnel junction applications, by plasma annealing at varying film thicknesses to obtain desired intrinsic film stress and breakdown film strength. The primary advantage of the ALD process is the near 100% step coverage with properties that are uniform along sidewalls. The process provides smooth (R a ˜2 Å), pure (impurities<1 at. %), AlO x films with improved breakdown strength (9–10 MV/cm) with a commercially feasible throughput.

Atomic layer deposition and conversion

Abstract: A method for growing films for use in integrated circuits using atomic layer deposition and a subsequent converting step is described. In an embodiment, the subsequent converting step includes oxidizing a metal atomic layer to form a metal oxide layer. The atomic layer deposition and oxidation step are then repeated to produce a metal oxide layer having sufficient thickness for use as a metal oxide layer in an integrated circuit. The subsequent converting step, in an embodiment, includes converting the atomic deposition layer by exposing it to one of nitrogen to form a nitride layer, carbon to form a carbide layer, boron to form a boride layer, and fluorine to form a fluoride layer. Systems and devices for performing the method, semiconductor devices so produced, and machine readable media containing the method are also described.