Pore-sealing process initiated by self-assembled layer for extreme low-k SiOCH (k&amp;#x003D;2.0)

Kobayashi, Akiko; Ishikawa, Dai; Matsushita, Kiyohiro; Kobayashi, Nozomu

doi:10.1109/iitc.2013.6615567

Cited by 6 publications

(17 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The transient absorption spectra of G •+ in one-electron oxidized DNA, recorded between 350 -700 nm using pulse radiolysis by Tagawa and coworkers, showed two absorption bands at around 400 nm (3.1 eV) and 480 nm (2.6 eV), respectively. 21,22 The time-resolved spectrum of one-electron oxidized oligonucleotides containing alternating G-C base pair (spectra recorded at 100 μs) shows absorptions at around 300, 400 and a band between 450 -550 nm, respectively. 20 The later values compare well with the absorption spectrum of the free guanine nucleoside cation radical (dGuo •+ ) recorded between 300 -700 nm, which show absorptions at around 300, 385 nm and a band extending from 470 -550 nm, respectively.…”

Section: (Iii) Vertical Excited States Of G •+ -C Base Pairmentioning

confidence: 99%

“…Pulse radiolysis 21,22 , ESR 19,40 experiments and theory 41 showed that G •+ , base paired with cytosine in DNA, transfers its N1 proton to N3 of cytosine, see structure G(N1-H) • -(H + )C in scheme 1(b). From deoxynucleosides in aqueous solution, it is known that the pK a of dG •+ for the N1 proton is 3.9 3,14 and pK a of N3-protonated dC is 4.3.…”

Section: (Iv) Vertical Excited States Of G(n1-h) • -(H + )C Base Pairmentioning

confidence: 99%

“…[10][11][12][13] Many works have identified the UVvis spectra of individual nucleoside cation radicals and their neutral deprotonated forms [13][14][15][16][17][18] , however, the absorption spectra of oxidized-DNA or base pairs are less well identified and a subject of some controversy. [19][20][21][22][23] Their identification is made difficult owing to various factors such as hydrogen-bonding, sequence, stacking interactions, and protonation/deprotonation reactions. [19][20][21][22][23][24] Very recently, using nanosecond transient absorption spectroscopy with 266 nm excitation, Markovitsi and coworkers 20 recorded the absorption spectra of one-electron oxidized duplex DNA of ten base pairs having alternate guanine-cytosine sequence.…”

Section: Introductionmentioning

confidence: 99%

“…[19][20][21][22][23] Their identification is made difficult owing to various factors such as hydrogen-bonding, sequence, stacking interactions, and protonation/deprotonation reactions. [19][20][21][22][23][24] Very recently, using nanosecond transient absorption spectroscopy with 266 nm excitation, Markovitsi and coworkers 20 recorded the absorption spectra of one-electron oxidized duplex DNA of ten base pairs having alternate guanine-cytosine sequence. With the aid of time-dependent density functional theory (TD-DFT) calculations the transient absorption spectra was characterized as deprotonated guanine radical (G(N1-H) • .…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Excited States of One-Electron Oxidized Guanine-Cytosine Base Pair Radicals: A Time Dependent Density Functional Theory Study

Kumar

Sevilla

2019

J. Phys. Chem. A

View full text Add to dashboard Cite

One-electron oxidized guanine (G •+) in DNA generates several short-lived intermediate radicals via proton transfer reactions resulting in the formation of neutral guanine radicals (scheme 1). The identification of these radicals in DNA is of fundamental interest to understand the early stages of DNA damage. Herein, we used time-dependent density functional theory (TD-ωB97XD-PCM/ 6-31G(3df,p)) to calculate the vertical excitation energies of one electron oxidized G and guanine(G)-cytosine(C) base pair in various protonation states: G •+ , G(N1-H) • and G(N2-H) • , as well as G •+-C, G(N1-H) •-(H +)C, G(N1-H) •-(N4-H +)C), G(N1-H) •-C and G(N2-H) •-C in aqueous phase. The calculated UV-vis spectra of these radicals are in good agreement with experiment for the G radical species when the calculated values are red-shifted by 40-70 nm. The present calculations show that the lowest energy transitions of proton transferred species (G(N1-H) •-(H +)C, G(N1-H) •-(N4-H +)C), and G(N1-H) •-C) are substantially red-shifted in comparison to the spectrum of G •+-C. The calculated spectrum of G(N2-H) •-C shows intense absorption (high oscillator strength) which matches the strong absorption in the experimental spectra of G(N2-H) • at 600 nm. The present calculations predict the lowest charge transfer transition from C→G •+ is π→π* in nature and lies in the UV-region (3.4-4.3 eV) with small oscillator strength.

show abstract

Section: (Iii) Vertical Excited States Of G •+ -C Base Pairmentioning

confidence: 99%

Section: (Iv) Vertical Excited States Of G(n1-h) • -(H + )C Base Pairmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Excited States of One-Electron Oxidized Guanine-Cytosine Base Pair Radicals: A Time Dependent Density Functional Theory Study

Kumar

Sevilla

2019

J. Phys. Chem. A

View full text Add to dashboard Cite

show abstract

“…For instance, a light plasma treatment (as described above) can narrow the pore diameter of the top surface without causing major damage, physically limiting the liner precursor penetration or diffusion. The results can also be obtained by chemical means: UV-assisted restoration 107 or silylation type treatments 108 can substitute silanols (formed during previous integration steps) with carbon groups, whose hydrophobic behavior inhibits interactions between pore walls and precursors.…”

Section: Ecs Journal Of Solid State Science and Technology 4 (1) N30mentioning

confidence: 99%

Toward Successful Integration of Porous Low-k Materials: Strategies Addressing Plasma Damage

Lionti

Volksen

Magbitang

et al. 2014

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

The increasing sensitivity of porous low dielectric constant materials to process damage constitutes a major roadblock to their implementation in back-end-of-the-line (BEOL) wiring structures for advanced technology nodes. In the early 2000s and in anticipation to future low-k related integration challenges, the semiconductor industry started to investigate the possibility to repair or prevent this damage. It is remarkable that the most disruptive solutions proposed today are inspired from the work initiated more than 10 years ago. In this review we first describe the accepted mechanisms for plasma damage, followed by a quick summary of the methods used to quantify its extent on both blanket films and patterned structures. We then report on the past and current strategies developed to mitigate the plasma damage of porous, low-k materials during damascene integration processes.

show abstract

Surface-Localized Sealing of Porous Ultralow-k Dielectric Films with Ultrathin (<2 nm) Polymer Coating

Yoon¹,

Pak²,

Nam

et al. 2017

ACS Nano

View full text Add to dashboard Cite

Semiconductor integrated circuit chip industries have been striving to introduce porous ultralow-k (ULK) dielectrics into the multilevel interconnection process in order to improve their chip operation speed by reducing capacitance along the signal path. To date, however, highly porous ULK dielectrics (porosity >40%, dielectric constant (k) <2.4) have not been successfully adopted in real devices because the porous nature causes many serious problems, including noncontinuous barrier deposition, penetration of the barrier metal, and reliability issues. Here, a method that allows porous ULK dielectrics to be successfully used with a multilevel interconnection scheme is presented. The surface of the porous ULK dielectric film (k = 2.0, porosity ∼47%) could be completely sealed by a thin (<2 nm) polymer deposited by a multistep initiated chemical vapor deposition (iCVD) process. Using the iCVD process, a thin pore-sealing layer was localized only to the surface of the porous ULK dielectric film, which could minimize the increase of k; the final effective k was less than 2.2, and the penetration of metal barrier precursors into the dielectric film was completely blocked. The pore-sealed ULK dielectric film also exhibited excellent long-term reliability comparable to a dense low-k dielectric film.

show abstract

Pore-sealing process initiated by self-assembled layer for extreme low-k SiOCH (k=2.0)

Cited by 6 publications

References 8 publications

Excited States of One-Electron Oxidized Guanine-Cytosine Base Pair Radicals: A Time Dependent Density Functional Theory Study

Excited States of One-Electron Oxidized Guanine-Cytosine Base Pair Radicals: A Time Dependent Density Functional Theory Study

Toward Successful Integration of Porous Low-k Materials: Strategies Addressing Plasma Damage

Surface-Localized Sealing of Porous Ultralow-k Dielectric Films with Ultrathin (<2 nm) Polymer Coating

Contact Info

Product

Resources

About