The Mechanical Property, Microstructure, and Pore Geometry of a Methyltrimethoxysilane Modified Silica Zeolite (MSZ) Film

Abstract

A methyltrimethoxysilane (MTMS) modified silica zeolite (MSZ) film has been prepared using a high ratio of MTMS/tetraethyl orthosilicate (TEOS). This study investigated the effect of MTMS addition on the low-k matrix structure, elastic modulus, and pore geometry. High MTMS loading reduced the k-value of MSZ film down to 2.0, but yielded a lower elastic modulus, 2.7 GPa. Based on grazing-incidence small-angle X-ray scattering (GISAXS) 2D pattern analysis, the pore geometry of the MSZ film was found to be small but elliptical (R in-plane ∼3.75 nm; R out-of-plane ∼3.04 nm). The elliptical pore shape was formed by a collapse of film structure at 150-160 • C as a result of ∼32% thickness shrinkage due to the decomposition of tetra-n-propylammonium hydroxide (TPAOH), a structure directing catalyst, and due to a large degree of crosslinking reaction in the silica matrix. Combining GISAXS, 29 Si-NMR, and FT-IR results, we propose that the lower elastic modulus was caused by the incorporation of a large amount of methyl groups from the MTMS precursor and the elliptic pores.In order to alleviate the signal delay issue in the backend interconnects as the scaling of the IC devices continues, the search for low-dielectric-constant (low-k) interlayer dielectrics remains to be the key materials solution, in addition to 3D interconnects and air-gap approaches. 1 According to 2010 ITRS, upcoming 22 nm technology node of IC industry requires dielectric materials with k-value <2.3. 2 Extensive efforts have been made in the last decade to attain ultra-low-k dielectrics (k ∼ 2.3-2.0). Researchers have introduced nanometer-scale pores into spin-on organosilicate dielectric films such as silsesquioxane based materials, whose k is ∼2.8 to 3.0 and E is in ∼3 to 7 GPa range at no porosity. 3 However, the mechanical strength of their corresponding ultra-low-k materials, which typically have high porosity, ∼50-60%, degrades significantly. 4 Moreover, the pore generators (porogens) within the spin-on organosilicate matrix tend to aggregate during the curing step and result in larger pores upon thermal decomposition, which further degrades mechanical strength of the dielectric film. 5 Overall, the mechanical strength of spin-on dielectric films has been a challenge for its use in the manufacturing of advanced integrated circuit.Recently, researchers have focused on low-k films with high mechanical modulus, such as pure silica-zeolite (PSZ) low-k film. PSZ low-k film offers several advantages over amorphous silica including crystalline structure as well as intrinsically uniform and small pore size. 6, 7 Typical PSZ materials have high modulus and low dielectric constant, but have challenges such as high surface roughness, 8 which can be resolved by adding a chemical mechanical polishing step. The other major problem is the high moisture absorption of PSZ film. 9, 10 This is disadvantageous for the practicability of PSZ film due to the k-value of water is close to 80.

The dual actions of modified polybenzimidazole in taming the polysulfide shuttle for long-life lithium–sulfur batteries

“…Compared with the pristine mPBI spectrum, the Li 2 S 4 -treated sample demonstrates a distinctly weakened peak at 3421 cm − 1 and a peak set~2922 cm − 1 in the fourier transform infrared spectrometry spectra (Figure 2a), which are assigned to the stretching vibration of isolated N-H and the self-associated N-H, respectively. 28 The C = N stretching vibration peak undergoes a blue shift from 1625.8 to 1654.8 cm − 1 , whereas the other two vibrations, which are at 1384 and 1049 cm − 1 , corresponding to aryl C-N stretching and alkyl C-N stretching, respectively, 29 almost disappear compared with the spectrum of the untreated mPBI. The changes to the nitrogen relevant peaks are attributed to the formation of the coordinated N-Li-S bond.…”

Effects of Methyl Terminal and Carbon Bridging Groups Ratio on Critical Properties of Porous Organosilicate Glass Films

“…The incidence beam was monochromated to a wavelength (λ) of 1.55 Å with Δλ/λ ≈ 10 −3 resolution. The detailed information of the detector, the scattering wave vector ( q ) range, incident angle and X-ray energy had been described in [ 12 ]. All GISAXS data were corrected for sample transmission, background, and the detector sensitivity.…”

Physical characterization of hafnium aluminates dielectrics deposited by atomic layer deposition

“…The total scattering intensity from the hafnium aluminate layers is the result of the partial contribution of these localized centers of scattering ,weighted by their volumetric fraction (f k ) [25], as describe by equation 7 in which the generalized OZ relationship was included: (7) where x k is the correlation length and n k is the fractal dimension of the centers of scattering (n =1, elongated; n =2, flatted or Gaussian chain-like; n =3, sphere-like with fractal surface; n = 4, hard spheres, i.e they can not overlap and have sharp borders) [20,24,25,41]. Although equation 7 was derived regarding non-interacting centers (condition b), it is important to highlight that OZ equation take into account the interaction of the centers, therefore, this equation can adequately describe polydispersive systems [42,43].…”