NH3 Plasma Research Articles

Interfacial reinforcement of composites by the electrostatic self-assembly of graphene oxide and NH3 plasma-treated carbon fiber

The introduction of graphene oxide (GO) on the surface of carbon fiber (CF) is considered an effective strategy to modulate the structure and properties of the fiber/matrix interface in CF reinforced polymer composites. However, the tensile strength of fibers often decreases due to the etching effect during treatment. In this study, a new method was proposed to graft GO onto fiber surfaces by electrostatic self-assembly. The results showed that NH2 grafted onto CF through NH3 plasma treatment caused CF and GO to have opposite charges in deionized water; subsequently, they self-assembled to form CF@GO due to the electrostatic force. The tensile strength of CF@GO was 31.23% greater than that of pristine CF, which may be because the different sizes of GO repaired the surface defects on the CF with its multilayer restoration structure. The CF showed a noticeable improvement in surface wettability due to the GO coating. Moreover, the interfacial properties were significantly improved, with the interfacial shear strength (IFSS) of CF@GO increasing to 81.31 MPa, which was about twice that of unmodified CF. This work provides a promising strategy for nondestructive grafting nanoparticles on CF to build a strong interface in CF composites.

Comparison of NH3 and N2O Plasma Treatments on Bi2O3 Sensing Membranes Applied in an Electrolyte-Insulator-Semiconductor Structure.

In this study, bismuth trioxide (Bi2O3) membranes in an electrolyte–insulator–semiconductor (EIS) structure were fabricated with pH sensing capability. To optimize the sensing performance, the membranes were treated with two types of plasma—NH3 and N2O. To investigate the material property improvements, multiple material characterizations were conducted. Material analysis results indicate that plasma treatments with appropriate time could enhance the crystallization, remove the silicate and facilitate crystallizations. Owing to the material optimizations, the pH sensing capability could be greatly boosted. NH3 or N2O plasma treated-Bi2O3 membranes could reach the pH sensitivity around 60 mV/pH and show promise for future biomedical applications.

Bidirectional catalyst design for lithium–sulfur batteries: phase regulation cooperates with N-doping

N-doping and phase regulation of MoS2via room temperature NH3 plasma technology achieve efficient bidirectional catalysis for lithium–sulfur electrochemistry.

Effects of NH3 Plasma and Mg Doping on InGaZnO pH Sensing Membrane.

In this study, the effects of magnesium (Mg) doping and Ammonia (NH3) plasma on the pH sensing capabilities of InGaZnO membranes were investigated. Undoped InGaZnO and Mg-doped pH sensing membranes with NH3 plasma were examined with multiple material analyses including X-ray diffraction, X-ray photoelectron spectroscopy, secondary ion mass spectroscopy and transmission electron microscope, and pH sensing behaviors of the membrane in electrolyte-insulator-semiconductors. Results indicate that Mg doping and NH3 plasma treatment could superpositionally enhance crystallization in fine nanostructures, and strengthen chemical bindings. Results indicate these material improvements increased pH sensing capability significantly. Plasma-treated Mg-doped InGaZnO pH sensing membranes show promise for future pH sensing biosensors.

Impacts of surface nitridation on crystalline ferroelectric phase of Hf1-xZrxO2 and ferroelectric FET performance

This paper presents an approach to enhance Hf0.5Zr0.5O2 (HZO) ferroelectric orthorhombic phase (O-phase) formation via in situ NH3 plasma treatment. High-resolution non-disruptive hard x-ray photoelectron spectroscopy confirmed that O-phase formation can be enhanced by suppressed interfacial diffusion between HZO and the top TiN electrode. Additional N-bonding facilitated by NH3 treatment was shown to suppress the interaction between TiN and HZO, thereby reducing the formation of oxygen vacancies within HZO. It was shown to improve the reliability and ferroelectric performance (examined by the leakage current and positive-up-negative-down measurements) of HZO devices. After cyclic operations, NH3-treated ferroelectric FETs (FeFETs) exhibited stable transfer characteristics and memory windows, whereas untreated devices presented unstable behaviors. Our results demonstrate the efficacy of the proposed in situ NH3-treatment scheme in enhancing the stability of HZO-based FeFETs.

(Invited) Atomic Level Precision in Near-Zero Thickness Thin Film Deposition Through Chemistry and Process Innovation

The semiconductor industry is being radically impacted by placing greater emphasis on the development of hetero-devices and systems that will act as essential drivers for a wide spectrum of technological applications across multiple industrial sectors. The introduction of new materials and their integration with currently used materials are projected to replace IC design and device scaling as the key enablers to the realization of improved device performance and larger density gains. Yet material selection has been constrained by existing fabrication process technology. To date, fabrication processes have dictated material selection by limiting chemical sources or precursors to those that match existing process tools associated with CVD and ALD and their variants, which in turn limits material compositions in ICs. The processing and integration of new materials structures will require the introduction of new deposition and etching processes, and manufacturing worthy protocols that provide new methods for atomic level control.This presentation explores four new such processes and protocols that match these requirements, namely: P-CVD SiNx: This process combines precursor thermal adsorption with the reaction with remote plasma ammonia. A demonstration is presented in which thermal adsorption of tri(isopropyl)cyclotrisilazane (TICZ) ensures a substrate driven nucleation and growth process that leads ultimately to conformal SiNx in extremely high aspect ratio structures. Concurrently, the application of a remote NH3 plasma eliminates any undesirable plasma-induced effects on the substrate and growing film. Single Pulse CVD/ALD: These are methods for pulsed deposition of thin films that offer significant reduction in the time to generate thin films by eliminating a number of the steps required in growth cycles. In the case of ALD, for instance, it reduces the number of steps required to grow every individual thin film layer from four to one, thus maximizing process efficiency and wafer throughput, and leading to competitive manufacturing cost of ownership and return on investment. The deposition of high quality cobalt films from cobalt tricarbonyl nitrosyl will be discussed in this context. Vapor Phase Transient Species Deposition. The discrete generation of transient species under conditions distinct from the substrate and the parent precursor will be discussed. This process enables the deposition of films in lower thermal or energetic substrate environments. It also enables the deposition of films at lower temperatures and ensures greater conformality of the deposited films, allowing film deposition on thermally or chemically fragile substrates. Integrated Synthesis and Deposition (ISD): A manufacturing paradigm comprising a method and system for real-time, closed-loop synthesis, supply, and consumption of precursors in IC manufacturing processes. In its simplest form, the system consists of a precursor synthesis chamber being physically interfaced with a thin film processing chamber, with precursor being synthesized on demand and supplied in a controlled fashion into the thin film processing chamber where it is consumed in the manufacturing process. This allows practical methods to employ highly reactive chemistry that otherwise could lead to explosive or highly toxic releases.

Nanostructure and functional group engineering of black phosphorus via plasma treatment for CO2 photoreduction

As an emerging two-dimensional (2D) semiconductor, black phosphorus (BP) has attracted great interest in photocatalytic CO2 reduction, but the performance is restricted by the low surface reactivity and poor stability. Exfoliating BP into the 2D structure is an effective method to increase the exposure of active sites. However, the intrinsic surface reactivity and stability cannot be improved, and, the widely used liquid-phase exfoliation method is time-consuming and laborious. In this work, we successfully exfoliates the bulk BP into ultrathin BP nanosheets with dense surface amino-functional groups (BP-NH2) using NH3 plasma treatment. The 2D structure can shorten the photo-excited charges migration distance and improve the exposure of surface-active sites. Furthermore, the amino-functional groups on ultrathin BP nanosheets can prevent the destruction of BP nanosheets in ambient air, favoring the charge separation, CO2 adsorption and activation during the catalytic process. Benefiting from integrated advantages of amino functional groups, the optimal BP-NH2 exhibits a photocatalytic CO2 reduction rate to CO of 27.6 μmol g−1 h−1 with a selectivity of 87.0 %, both of which are higher than those of pristine bulk BP. This work presents ideas for stabilizing BP and improving the CO2 reduction performance simultaneously.

Oxygen diffusion barrier on interfacial layer formed with remote NH3 plasma treatment

An oxidation or nitridation treatment was performed on the interfacial layer (IL) with optimal oxidation state in order to form an oxygen diffusion barrier for Ge nMOSFET . Through the analysis of X-ray photoelectron spectroscopy and electrical characterization of Ge nMOSFET, the reaction mechanism and physical model were studied in details. The fewer interface traps and lower subthreshold swing can be achieved by forming oxygen diffusion barrier in an optimal IL with remote NH 3 plasma. As compared to devices with oxidation treatments , that improvement can be attributed to the nitrogen passivation and alloy-like interface formation. The proposed oxygen diffusion barrier with remote NH 3 plasma treatment on IL is a promising technique to improve the interface properties effectively without influencing equivalent oxide thickness for high performance Ge nMOSFET. • An interfacial layer buffer formation method is proposed. • An oxygen diffusion barrier can be formed by remote plasma treatment. • A n-channel Ge transistor can be enhanced by NH 3 plasma. • Reaction mechanism about oxygen diffusion is explained by material analysis.

Combined effects of NH3 and NF3 post plasma treatment on the performance of spray coated ZnO thin film transistors

We investigate the effects of NH3 and NF3 post plasma-treatment on the performance of spray-coated ZnO thin film transistors (TFTs). Both NH3 and NF3 plasma treatment are varied from 10 to 40 s. The properties of plasma treated ZnO were studied by Hall Effect measurements, UV–visible spectroscopy, photoluminescence, atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. NF3 plasma treatment causes n-type doping and generates carriers by F incorporation. While, NH3 plasma can cause not only n-type doping by Hydrogen incorporation but also creates acceptor-like states by the formation of Vo–H complex and inducing Nitrogen in ZnO. Owing to the N incorporation, the threshold voltage can be controlled by NH3 plasma treatment. The appropriate NH3 and NF3 plasma treatments for 10 s each greatly enhance theperformance of ZnO TFTs, exhibiting the saturation mobility and subthreshold swing of 20.65 cm2 V−1 s−1 and 0.18 V dec–1, respectively. Therefore, it is concluded that NH3 and NF3 plasma-treatment can be a useful technique to enhance the device performance and to improve the stability of solution-processed metal-oxide TFTs.

The Evolution of Organosilicon Precursors for Low-k Interlayer Dielectric Fabrication Driven by Integration Challenges.

Since the application of silicon materials in electronic devices in the 1950s, microprocessors are continuously getting smaller, faster, smarter, and larger in data storage capacity. One important factor that makes progress possible is decreasing the dielectric constant of the insulating layer within the integrated circuit (IC). Nevertheless, the evolution of interlayer dielectrics (ILDs) is not driven by a single factor. At first, the objective was to reduce the dielectric constant (k). Reduction of the dielectric constant of a material can be accomplished by selecting chemical bonds with low polarizability and introducing porosity. Moving from silicon dioxide, silsesquioxane-based materials, and silica-based materials to porous silica materials, the industry has been able to reduce the ILDs’ dielectric constant from 4.5 to as low as 1.5. However, porous ILDs are mechanically weak, thermally unstable, and poorly compatible with other materials, which gives them the tendency to absorb chemicals, moisture, etc. All these features create many challenges for the integration of IC during the dual-damascene process, with plasma-induced damage (PID) being the most devastating one. Since the discovery of porous materials, the industry has shifted its focus from decreasing ILDs’ dielectric constant to overcoming these integration challenges. More supplementary precursors (such as Si–C–Si structured compounds), deposition processes (such as NH3 plasma treatment), and post porosity plasma protection treatment (P4) were invented to solve integration-related challenges. Herein, we present the evolution of interlayer dielectric materials driven by the following three aspects, classification of dielectric materials, deposition methods, and key issues encountered and solved during the integration phase. We aim to provide a brief overview of the development of low-k dielectric materials over the past few decades.

In vacuo XPS investigation of surface engineering for lithium metal anodes with plasma treatment

Lithium (Li) metal is an attractive anode material with high capacity (3860 mAh g−1) and low potential (−3.04 V vs. standard hydrogen electrode) that shows highly promising for applications requiring high energy density. However, the low electrochemical potential of Li metal makes it extremely reactive and inevitably forming a native oxidized layer in the ambient environment and repeatedly being consumed when exposed to liquid electrolytes. It is therefore beneficial to replace the poorly controlled native passivation layer with a tailored artificial SEI to improve interface management between Li and electrolyte and enhance the stability of Li metal battery. Here, we use an integrated glovebox-atomic layer deposition (ALD)- X-ray photoelectron spectroscopy (XPS) setup to in-situ investigating the pristine Li surface and the surface composition after Ar, H2, O2, N2 and NH3 plasma treatment processes. We find that the pristine Li foil is naturally being covered with a native oxidized layer, which is mainly composed of LiOH, Li2O and Li2CO3. These investigated plasmas can efficiently remove the oxidized layer from the Li metal surface, in which metallic Li surface is obtained after Ar or H2 plasma treatments, where Ar plasma is more efficient. While O2 plasma treatment produces a Li2O layer, and N2 or NH3 plasma treatment leads to a Li3N (including a certain amount of LiON) layer on the Li surface. When employing the representative metallic Li (by Ar plasma treatment), Li2O layer coated Li (by O2 plasma treatment) and Li3N layer coated Li (by N2 plasma treatment) foils as electrodes in symmetric Li metal batteries, the Li3N coated Li electrode exhibits much higher stability than that of metallic and Li2O layer coated Li foils. Improved electrochemical performance has also been achieved in LiMn2O4 (LMO)||Li full cells using Li anode with Li3N protective coating layer. Our work reveals the detailed process of surface engineering of Li metal anodes with plasma treatments by in vacuo XPS, which may also be extended to other gas-treatment or plasma-treatment for stabilization of high energy density Li metal anodes and other metal-based anodes.

Cu/HZSM-5 Sorbent Treated by NH3 Plasma for Low-Temperature Simultaneous Adsorption-Oxidation of H2S and PH3.

In this study, an NH3 plasma-treated Cu/HZSM-5 sorbent was introduced to simultaneously remove H2S and PH3 in low-temperature and low-oxygen environments. The effects of the Cu loading amounts, modification methods, and plasma-treatment conditions on the adsorption-oxidation performance of the sorbents were investigated. From the performance test results, the sorbent treated by NH3 plasma with the specific energy input (SEI, electrical input energy to the unit volume of gas) value of 1 J·mL-1 (Cu/HZSM-5-[S1]) was identified as having the highest breakthrough capacities of 108.9 mg S·g-1 and 150.9 mg P·g-1 among all of the materials tested. After three times of regeneration, the sorbent can still maintain the ideal performance. The results of Fourier transform infrared (FT-IR) spectroscopy and CO2 temperature-programmed desorption (CO2-TPD) indicated that the NH3 plasma treatment can introduce amino groups (functional groups) onto the sorbent surface, which greatly increases the number and strength of the basic sites on the sorbent surface. Results of N2 adsorption/desorption isotherms and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) showed that the morphology of the sorbent changed after the plasma treatment, which exposed more active sites (copper species). In situ IR spectra showed that the amino groups are continuously consumed during the reaction process, indicating that these amino groups can help sorbents to capture gas molecules. Moreover, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses indicated that CuO is the main active species and the consumption of CuO and accumulation of the reaction products on the surface and inner pores of the sorbent are the primary reasons for the deactivation of the sorbent.

Study on Hydrogen-Based Reactive Ion Etching of Ovonic Threshold Switch (OTS) Materials for Phase Change Memory Devices

Ovonic threshold switch (OTS) materials are used in selector devices for phase change random access memory (PcRAM) circuits and are generally composed of chalcogenide compounds. In this study, etch characteristics of OTS material composed of Ge-As-Te have been investigated using reactive ion etching (RIE) by hydrogen-based gases such as H2, CH4, NH3, etc. Among the investigated hydrogen-based plasmas, NH3 showed the highest etch rate due to the high vapor pressures of the hydrides, but the formation of nitride compounds and the increased roughness were observed on the OTS surface. In the case of CH4+NH3 (1:1 ratio) plasma, the OTS material could be etched at high OTS etch rates without the formation of nitrogen compounds and without increasing the chemical and physical damage on the OTS surface through the formation of volatile CN-related compounds.

Functional carbon materials processed by NH3 plasma for advanced full-carbon sodium-ion capacitors

The pseudocapacitive storage mechanism of ClO 4 − and Na ions in cathode and anode were explored for the first time with NH 3 plasma strategy. In-situ/ex-situ characterizations and density functional theory (DFT) calculations demonstrate that pyridinic-N and C O could efficiently increase the defects and tune the adsorb properties of ClO 4 − , and build up an expressway for fast Na ions transfer, which further illustrates the “adsorption-pseudocapacitive reactions ”processes of cathodes and “adsorption-pseudocapacitive reactions-intercalation” processes of anodes. • N/O pseudocapacitive sites can be controlled by NH 3 plasma. • Revealing the reversible evolution of Pyridinic-N/C O. • Classifying the different mechanism in SICs. High-performance sodium-ion capacitors (SICs) are regarded as new-generation electrochemical energy-storage systems that are critically restricted due to the kinetic and capacity mismatch between the capacitor-type cathode and battery-type anode derived from the low capacity of carbon cathodes and the weak charge transfer kinetics of the anodes. In this study, for the first time, we investigate the pseudocapacitive storage mechanism of both ClO 4 − and Na ions in carbon cathode/anode with a novel NH 3 plasma strategy at room temperature. Interestingly, the implementation of pseudocapacitance greatly enhances the capacity in cathodes and the kinetics in anodes, effectively reducing the mismatch between two electrodes. With the ingenious NH 3 plasma strategy, which breaks the barriers of conventional methods of synthesizing N-functional carbon materials, various types and substances of N/O pseudocapacitive sites can be controlled directionally and accurately. The time-sensitive NH 3 plasma treatment utilized in this work has been demonstrated to be a state-of-art method for producing high content of pyridinic-N/C O bond and introducing ultrafast pseudocapacitance on the surface of the samples. Impressively, in-situ/ex-situ characterizations demonstrate the highly reversible evolution of Pyridinic-N and C O during the charging/discharging processes in cathodes/anodes, which is well consistent with electrochemical results and DFT calculations, presenting the “adsorption-pseudocapacitive reactions” and “adsorption-pseudocapacitive reactions-intercalation” mechanisms for cathodes and anodes respectively. Furthermore, the SICs deliver an energy density of 107 W h kg −1 at a power density of 200 W kg −1 . The current results are expected to be a powerful tool and an exciting opportunity to accelerate the practical application of SICs and achieve high-performance cathodes and anode materials.

Crystalline AlN Interfacial Layer on GaN Using Plasma-Enhanced Atomic Layer Deposition

In this study, we report on the deposition of a highly crystalline AlN interfacial layer on GaN at 330 °C via plasma-enhanced atomic layer deposition (PEALD). Trimethylaluminum (TMA) and NH3 plasma were used as the Al and N precursors, respectively. The crystallinity and mass density of AlN were examined using X-ray diffraction (XRD) and X-ray reflectivity (XRR) measurements, respectively, and the chemical bonding states and atomic concentrations of the AlN were determined by X-ray photoelectron spectroscopy (XPS). The AlN/n-GaN interface characteristics were analyzed using TOF-SIMS and STEM, and the electrical characteristics of the AlN were evaluated using metal-insulator-semiconductor (MIS) capacitors. The PEALD process exhibited high linearity between the AlN thickness and the number of cycles without any incubation period, as well as a low carbon impurity of less than 1% and high crystal quality even at a low deposition temperature of 330 °C. Moreover, the GaN surface oxidation was successfully suppressed by the AlN interfacial layer. Furthermore, enhanced electrical characteristics were achieved by the MIS capacitor with AlN compared to those achieved without AlN.

Plasma-induced moieties impart super-efficient activity to hydrogen evolution electrocatalysts

Abstract Having a high combustion value (1.4 × 108 J/kg) with an intrinsically green nature, hydrogen has been widely regarded as the next generation energy alternative to the conventional fossil fuels that have caused severe environmental issues associated with the rapidly increasing CO2 emissions, including global warming, sea level rising and species extinction. Thus, it is important to develop highly efficient and cost-effective catalysts for hydrogen generation. Herein, we fabricated a novel NiMoO4 catalyst on Ni foams, followed by NH3–plasma treatment to introduce NH2 functional groups, which were then transformed into –NH3 moieties during the HER process to afford a superb HER activity in alkaline solution, approaching the theoretical limit. The resultant NHx-NiMoO4 HER catalyst was demonstrated to be super-active with a record high HER performance (η @ 10 mA cm−2 = 18 mV, Tafel slope = 28.3 mV/decade) and promising for sea-water splitting. The theoretical studies suggest that NH3 moieties suffered from reorganization towards minimizing the energy barriers for both Volmer and Tafel/Heyrovsky steps. The plasma method may be extended to the design of novel catalysts for many other important chemical or electrochemical reactions.

Semi-insulating GaAs surface modifications and their influence in the response of THz devices

In this work, we use the Metal-Assisted Chemical Etching (MACE) technique together with an NH3 plasma treatment using a Remote Plasma-Enhanced Chemical Vapor Deposition (RPECVD) equipment to modify the surface of semi-insulating GaAs (SI-GaAs) substrates. Using our modified SI-GaAs, we fabricate photoconductive antennas for THz emission to study the modification's influence on the optical and electrical antenna response. We found substantial gaps in the frequency-domain spectra of the devices, whose origin could reside in a change of the substrate's optical absorption due to: (a) a surficial chemical change or (b) a substrate topographic modification or a combination of both. We showed experimentally that slight and reproducible substrate surface modifications could lead to significant variations in the electrical behavior and THz response of SI-GaAs devices.

Characteristics of Cobalt Thin Films Deposited by Very High Frequency Plasma Enhanced Atomic Layer Deposition (60 and 100 MHz) Using Cobaltocene (Co(Cp)2)/NH3

In this study, cobalt films were deposited by plasma enhanced atomic layer deposition (PEALD) with cobaltocene (Co(Cp)₂) using two different very high frequency (VHF) NH₃ plasmas (60 MHz, 100 MHz), and the effect of different frequencies of VHF on the characteristics of NH₃ plasmas and the properties of cobalt films were investigated. It is found that the higher frequency showed the higher plasma density at the same input power and, the NH radicals, which are required to remove the ligands of the cobalt precursor during the plasma exposure step in the ALD cycle, were higher at 100 MHz than those at 60 MHz. The RMS surface roughness and carbon impurity percentage of the deposited cobalt films were lower at the higher frequency possibly indicating denser films due to more active surface reactions at the higher frequency. As a result, it is expected that the cobalt thin films deposited by the higher VHF PEALD will improve the characteristics of deposited thin films.

Surface modification and properties modulation of rGO film by short duration H2 and NH3 plasma treatment

Reduced graphene oxide (rGO) is a versatile material due to the presence of oxygen functionalization. One of the methods to tune the properties of rGO for the specific application is plasma treatment. Plasma H 2 and NH 3 are known introduced surface defects for increasing surface reactivity and inducing substitutional doping on rGO film. They need to be further discussed with the changes in electrical and optical properties of the film for the construction of devices such as electrical, optical, and electro-optical sensors. This article reports the effect of H 2 and NH 3 plasma treatment on the surface and properties of rGO film using a variety in plasma power and temperature. We found low-power H 2 plasma at low- and medium-temperature induced further de-oxygenation of rGO. A tiny etching effect by H 2 plasma slightly reduces the conductivity, σ to 54.01 S/cm from the reference rGO value of 448.90 S/cm. Low-power H 2 plasma at high-temperature left the high defective sites due to plasma etching. The σ was reduced to 8.04 S/cm. Medium-temperature medium-power NH 3 plasma did not effective for N-doping. An etching effect by NH 3 plasma noticeably reduces the σ to 5.79 S/cm. Medium-temperature high-power and high-temperature medium-power NH 3 plasma induce N-doping but at the same time significantly etch the rGO. They significantly reduce the hole concentration and lower the σ to 0.48 S/cm. High-power high-temperature NH 3 plasma rigorously induces N-doping but extreme plasma etching results in poor surface condition and film discontinuity. The film exhibited electron as a majority carrier but with the lowest σ of 0.05 S/cm.

Magnetoresistive properties of cobalt thin films grown by plasma-assisted atomic layer deposition

Cobalt thin films have been grown by plasma-enhanced atomic layer deposition using bis(cyclopentadienyl)cobalt(II) as cobalt precursor and NH3 plasma as a reducing agent. Electric and magnetic properties are investigated as a function of the growth temperature. A transition from a regime of temperature independent film thickness to a thermally-activated growth is observed at 340 °C. In the self-limited growth regime, magnetization increases and resistivity decreases with temperature. On the contrary, in the thermally-activated regime, magnetization decreases and resistivity increases with temperature. This results in an optimal growth temperature of 340 °C at which the magnetization equals bulk cobalt and the resistivity is 14 µΩ cm. Rotating magnetic field measurements show a magnetoresistance of 1.1% at room temperature ascribed to conventional anisotropic magnetoresistance. This study shows that magnetoresistive properties of cobalt thin films grown by atomic layer deposition are comparable to those obtained by physical vapor deposition and reveals that atomic layer deposition might be an alternative deposition technique for ferromagnetic layers in the field of spintronics.