Effects of O3 and H2O oxidants on C and N-related impurities in atomic-layer-deposited La2O3 films observed by <i>in situ</i> x-ray photoelectron spectroscopy

Park, Tae Joo; Sivasubramani, P.; Coss, Brian E.; Kim, Hyun-Chul; Lee, Bongki; Wallace, Robert M.; Kim, Jiyoung; Rousseau, M.; Liu, Xinye; Li, Huazhi; Lehn, Jean Sebastien; Hong, Deokhwa; Shenai, Deo

doi:10.1063/1.3481377

Cited by 22 publications

(18 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, the variation of the degree of reduction of the percentage composition of C impurity for sample A is more severe than that for the other samples after annealing. This result indicates that the film using O 3 as an oxidant is more prone to achieve the saturation adsorption reaction and has a greater advantage in controlling the C impurity level compared with the film using H 2 O as an oxidant [19]. On the other hand, the percentage composition of N impurity for as-deposited sample D is higher than that for the other samples shown in Fig.…”

Section: Resultsmentioning

confidence: 98%

See 1 more Smart Citation

Effects of Rapid Thermal Annealing and Different Oxidants on the Properties of LaxAlyO Nanolaminate Films Deposited by Atomic Layer Deposition

et al. 2017

View full text Add to dashboard Cite

A comparative study of different sequences of two metal precursors [trimethylaluminum (TMA) and Tris(isopropylcyclopentadienyl) lanthanum (La(iPrCp)3)] for atomic layer deposition (ALD) lanthanum aluminum oxide (LaxAlyO) films is carried out. The percentage compositions of C and N impurity of LaxAlyO films were investigated using in situ X-ray photoelectron spectroscopy (XPS). The effects of different oxidants on the physical and chemical properties and electrical characteristics of LaxAlyO films are studied before and after annealing. Preliminary testing results indicate that the impurity level of LaxAlyO films grown with different oxidants can be well controlled before and after annealing. Analysis indicates the rapid thermal annealing (RTA) and kinds of oxidants have significant effects on the equivalent oxide thickness (EOT), dielectric constant, electrical properties, and stability of LaxAlyO films. Additionally, the change of chemical bond types of rapid thermal annealing effects on the properties of LaxAlyO films are grown with different oxidants also investigated by XPS.

show abstract

Section: Resultsmentioning

confidence: 98%

“…ALD is also suitable for depositions on trench-type structures. Also, for thin films, the ALD produces better uniformity and lesser defects as compared to other deposition techniques [18, 19]. These qualities make the ALD method attractive for manufacturing of future generation integrated circuits especially gate dielectric applications.…”

Section: Introductionmentioning

confidence: 99%

Effects of Rapid Thermal Annealing and Different Oxidants on the Properties of LaxAlyO Nanolaminate Films Deposited by Atomic Layer Deposition

et al. 2017

View full text Add to dashboard Cite

show abstract

“…This issue is also closely related to the type of oxygen source because the physical density, crystallinity, and film morphology, which affect the Si diffusion behavior, should be influenced by the type of oxygen source. Park et al recently reported that the O 3 process suppressed a silicate phase formation by retarding Si diffusion into the high-k film due to the higher physical density of the film, but it was also found to increase the interfacial layer growth during ALD compared to the H 2 O process [36]. The initial island-like film growth in the HfO 2 grown using H 2 O results in a smaller grain size (larger number of grain boundary through the film) in the film compared to the film grown using O 3 [30], which enhances Si diffusion into the high-k film during ALD and PDA [15].…”

Section: H 2 O Versus Omentioning

confidence: 99%

Atomic Layer Deposition Process of Hf‐Based High‐ k Gate Dielectric Film on Si Substrate

Park

Cho

Jung

et al. 2012

High‐k Gate Dielectrics for CMOS Technology

Self Cite

View full text Add to dashboard Cite

Hf-based gate dielectrics with a metal gate have been implemented in the mass production of state-of-the-art complementary metal oxide semiconductor field effect transistors (CMOSFETs) because SiO 2 gate dielectrics have already reached their physical limit due to the high leakage current and reliability concerns [1]. With this radical change in the gate dielectric material, other related materials, such as gate metal and spacers, as well as integration processes have also undergone unprecedented innovation over the past decade. There are several other notable changes in characterizing the device properties, which are still highly important research areas in microelectronics and are discussed in other chapters of this book.Some of the critical issues and related material processing are closely related to the material properties of high-k dielectric films, which are determined largely by the processing conditions of thin films. Atomic layer deposition (ALD) has been the industry standard process of the high-k gate dielectrics as well as several related materials. The merits of ALD include accurate thickness control, low thermal budget, good uniformity, and conformality. The conformality has not been the critical requirement for conventional planar MOSFETs but its importance is increasing as the three-dimensional structures, e.g., FinFET, are gaining more focus. The low thermal budget is another merit of ALD compared to chemical vapor deposition (CVD), particularly the gate-last integration scheme.ALD of high-k oxide films proceeds by alternately exposing the substrates to precursor and oxygen source that undergo self-terminating reactions with each other on the substrate surface. The metal half-cycle of ALD involves exposure of the growth surface to a gas-phase Hf precursor. After a purge of the reactor, the substrate is exposed to the oxygen source, which is followed by a subsequent purge, resulting in the formation of HfO 2 films. The thickness of the HfO 2 films can be controlled by repeating this reaction cycle. The selection of Hf precursor and oxygen source strongly affects the physical and electrical properties of the ALD HfO 2 films. As the High-k Gate Dielectrics for CMOS Technology, First Edition. Edited by Gang He and Zhaoqi Sun. ALD depends more on the specific chemistry and reaction route, compared to CVD. As ALD has evolved rapidly over the past several decades (ALD was first suggested by Professor Suntola in the early 1980s. [2]), a wide range of chemistry has become available, including inorganic and organic precursors.This chapter examines the issues related to the ALD processes of HfO 2 -based dielectric materials. The topics include the film properties and interactions with the Si substrate depending on the types of Hf precursor and oxygen sources. Although some chemistry aspects of ALD process itself are discussed but not mainly focused in this chapter. This chapter shows that various structural, physicochemical, and electrical characteristics of dielectric films are closely related to the deta...

show abstract

“…The previous report by Park et al expected the slightly thicker IL in the La 2 O 3 film grown using O 3 compared to La 2 O 3 film grown using H 2 O based on the XPS results. 4 However, the La precursor used in their work does not contain Si resulting in La 2 O 3 film, not La-silicate film, and the expectation based on the chemical analysis could be different from that based on the electrical measurements. 4 Considering that the physical thickness of IL in La-based films is hard to be defined due to no distinct contrast in a high-resolution transmission electron microscopy image, 12 and the IL consists of mainly SiO 2 , the similar electrical thickness of IL suggests that the difference in the physical thickness of the IL by the type of oxygen source might not be considerable.…”

mentioning

confidence: 98%

“…3 Additionally, serious Si diffusion from the substrate into the La 2 O 3 film during deposition have been reported. 4,5 The use of Si-containing Tris[bis(trimethylsilyl)amino]lanthanum, La[N(SiMe 3 ) 2 ] 3 , as a La precursor was reported as the promising way to intentionally incorporate Si in La 2 O 3 film to prevent the diffusion of Si from Si substrates. 6 Since, significant Si diffusion during ALD of La 2 O 3 film and post-deposition annealing degrades the gate controllability by increasing permittivity of the gate oxide film, the use of Lasilicate film instead of La 2 O 3 film is more attractive.…”

mentioning

confidence: 99%

Effects of Oxygen Source on Film Properties of Atomic-Layer-Deposited La-Silicate Film Using La[N(SiMe3)2]3

Choi

Won

Jung

et al. 2012

ECS Solid State Letters

View full text Add to dashboard Cite

The effect of oxygen sources, i.e. O 3 or H 2 O, on chemical composition, dielectric constant and leakage current density of atomiclayer-deposited La-silicate films was examined. The dielectric constant of La-silicate films grown using O 3 was ∼8.0, which was lower than that of La-silicate films grown using H 2 O, ∼11.7 due to the higher Si concentrations. However, leakage current density of La-silicate films grown using O 3 was about 3 orders of magnitude lower than that of La-silicate films grown using H 2 O at an identical capacitance-equivalent-thickness (but almost half the physical thickness), due to the higher Si concentrations and less La-carbonate formation.As the next generation high-k dielectric film as well as the threshold voltage control layer, La 2 O 3 film are attracting much attention nowadays due to their high dielectric constant (∼30) 1,2 and large conduction band offset (CBO) with Si (∼2.3 eV). 1 However, atomic layer deposition (ALD) of La-containing films has several challenges such as the limited selection of precursors and inducement of unstable film growth due to its hygroscopic behavior. 3 Additionally, serious Si diffusion from the substrate into the La 2 O 3 film during deposition have been reported. 4,5 The use of Si-containing Tris[bis(trimethylsilyl)amino]lanthanum, La[N(SiMe 3 ) 2 ] 3 , as a La precursor was reported as the promising way to intentionally incorporate Si in La 2 O 3 film to prevent the diffusion of Si from Si substrates. 6 Since, significant Si diffusion during ALD of La 2 O 3 film and post-deposition annealing degrades the gate controllability by increasing permittivity of the gate oxide film, the use of Lasilicate film instead of La 2 O 3 film is more attractive. Even though the chemical properties of ALD La-silicate films using La[N(SiMe 3 ) 2 ] 3 and H 2 O were reported, 6-9 a systematic study on the influence of the type of oxygen source, H 2 O or O 3 , on the growth behavior and electrical properties of La-silicate films using La[N(SiMe 3 ) 2 ] 3 has been rarely reported. 10 In this study, the ALD behavior and electrical properties of La-silicate films according to the type of oxygen source were examined. In particular, the changes in Si concentration of the ALD La-silicate film grown using the La[N(SiMe 3 ) 2 ] 3 precursor were focused.La-silicate films were grown on a HF-cleaned p-type (100) Si substrate at a wafer temperature of 310 • C in a traveling-wave type 4-in. thermal ALD reactor with a liquid delivery system using La[N(SiMe 3 ) 2 ] 3 as the metal precursor. O 3 of 110 g/Nm 3 and H 2 O at room temperature were used as the oxygen sources for O 3 -La-silicate and H 2 O-La-silicate films, respectively. La[N(SiMe 3 ) 2 ] 3 was vaporized at 190 • C and delivered to the reactor in the Ar carrier gas of 200 sccm. The injection time of La[N(SiMe 3 ) 2 ] 3 dissolved in hexane was controlled in milliseconds to precisely deliver it to a vaporizer. The injection time for La source, H 2 O and O 3 was fixed at 0.1ms, 1s and 5s, respectively. The base pressure of th...

show abstract

Effects of O3 and H2O oxidants on C and N-related impurities in atomic-layer-deposited La2O3 films observed by in situ x-ray photoelectron spectroscopy

Cited by 22 publications

References 21 publications

Effects of Rapid Thermal Annealing and Different Oxidants on the Properties of LaxAlyO Nanolaminate Films Deposited by Atomic Layer Deposition

Effects of Rapid Thermal Annealing and Different Oxidants on the Properties of LaxAlyO Nanolaminate Films Deposited by Atomic Layer Deposition

Atomic Layer Deposition Process of Hf‐Based High‐ k Gate Dielectric Film on Si Substrate

Effects of Oxygen Source on Film Properties of Atomic-Layer-Deposited La-Silicate Film Using La[N(SiMe3)2]3

Contact Info

Product

Resources

About