Polyimide-silica Hybrid Films Research Articles

Fluorinated polyimide–silica films with low permittivity and low dielectric loss

A sol–gel process was used to prepare polyimide–silica hybrid films from the fluorinated polyimide precursors (6FDA-ODA) and tetraethylorthosilicate (TEOS) in N,N-dimethyl acetamide. The hybrid film was then treated with hydrofluoric acid to remove the dispersed silica particles, leaving inside the film pores with diameters ranged from 80 nm to 1 μm, which depended on the size of the silica particles. The chemical structures and morphology of the hybrid and porous films were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The synthesized porous fluorinated polyimide films show low relative dielectric permittivity of 1.9, rendering them promising for microelectronic packaging materials.

Preparation and properties of polyimide–silica hybrid films with conjugation of the polyimide and silica by a sol–gel process using 3-(triethoxysilyl)propyl succinic anhydride

New polyimide–silica hybrid materials were prepared using the polyamic acid synthesized by copolymerization of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), 4,4′-oxydianiline (ODA) and an A 2A′-type tri-functional amine, 1,1-bis(4-(aminophenoxy)phenyl)-1-(4-(4-amino-2-trifluoromethylphenoxy)phenyl)ethane (1) (BTDA:ODA:1 = 7:6:1 in the molar). 3-(Triethoxysilyl)propyl succinic anhydride(TESSA) was reacted with amino groups in polyamic acid to introduce ethoxysilyl moiety which act as conjugation site for silica. The polyimide–silica hybrid films were prepared by a sol–gel reaction of tetraethoxysilane (TEOS) in a solution of the polyamic acid, followed by thermal imidation. Self-standing films were obtained with up to 50 wt.% silica, and transparent films were obtained at up to 40 wt.% silica. Dynamic-mechanical and mechanical analyses were carried out to examine the properties of hybrid films.

Study on the Dielectric Properties of Hybrid and Porous Polyimide-Silica Films

A sol-gel process was used to prepare polyimide-silica hybrid films from the polyimide precursors and TEOS in N,N- dimethyl acetamide, then the hybrid film was treated with hydrofluoric acid to remove the dispersed silica particles, leaving pores with diameters between 80nm to 1µm, depending on the size of silica particles. The structure and dielectric constant of the hybrid and porous films were characterized by FTIR,SEM. The porous films displayed relatively low dielectric constant compared to the hybrid polyimide-silica films.

Synthesis and cryogenic properties of polyimide–silica hybrid films by sol–gel process

Polyimide–silica hybrid films were prepared from tetraethoxysilane (TEOS) and polyamic acid (PAA) via sol–gel process in the solution of N,N-dimethylacetamide (DMAc). The cryogenic mechanical and electrical properties of polyimide–silica hybrid films were studied taking into account the effects of silica content. The results indicated that the cryogenic modulus increased with the increase of silica content while the tensile strength and failure strain had a maximum value at proper silica contents. Moreover, the tensile strength and modulus of the hybrid films at cryogenic temperature (77K) were obviously higher than those at room temperature, while the failure strain of the hybrid films was much lower at cryogenic temperature (77K) than that at room temperature. The mean electrical breakdown strength of the hybrid films was shown to range from 151 to 225kV/mm at cryogenic temperature (77K).

Polyimide–silica hybrid films made from polyamic acids containing phenolic hydroxyl groups

AbstractA diamine and polyamic acid containing phenolic hydroxyl group was synthesized. A series of polyimide/silica hybrid films with strong interacton between organic and inorgamic components was prepared via sol–gel reaction. The morphology of the hybrid films was investigated by scanning electron microscopy and atomic force microscopy. The thermal stability and mechanical properties of the films were detected. The results indicated that the introduction of phenolic hydroxyl groups remarkably attributed to the improvement of tensile strength. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1198–1202, 2004

Synthesis and properties of new polyimide–silica hybrid films through both intrachain and interchain bonding

In this study, the new polymer–silica hybrid materials were prepared based on the organo-soluble polyimides of 4,4′-hexafluoroisopropylidenediphthalic anhydride (6FDA) and four diamines. 3-Aminopropyl trimethoxysilane (APrTEOS) and γ-glycidyloxypropyltrimethoxysilanes (GOTMS) were used to increase the intrachain chemical bonding and interchain hydrogen bonding between the polyimide and silica moieties, respectively. The chemical interaction would significantly affect the morphologies and properties of the prepared films. Highly homogeneous hybrid thin films were obtained according to the studies of atomic force microscopy and TEM. The silica size observed by the TEM picture was smaller than 5 nm. The thermal properties of the organo-soluble polyimides were significantly enhanced by hybridizing only 6.30–7.99 wt% of silica. The intrachain chemical bonding could effectively enhance the coefficient of thermal expansion in comparison with the interchain interaction. Low dielectric constants in the range of 2.85–3.73 were obtained for the prepared hybrid films. The refractive indices of the prepared materials could be tuned through the polyimide structure or the silica content. The optical losses of the planar waveguides based on the prepared polyimides and their hybrids at 1310 nm were in the range of 0.5–2.7 dB/cm, which were mostly due to the higher harmonics of the aromatic C–H vibration and the extrinsic loss. The prepared polyimide–silica hybrid materials could have potential applications for microelectronics or optical communications.

New polyimide–silica organic–inorganic hybrids

AbstractA series of polyimide–silica hybrid films with silica contents up to 30 wt % were successfully prepared by the sol‐gel reaction of tetraethoxysiliane in the presence of poly(amic acid) containing pendent hydroxyl groups. The films were yellow and transparent when the silica content was less than 11 wt %. The chemical structure of the films was characterized by Fourier transform infrared spectroscopy, and the morphology of the films was investigated by scanning electronic microscopy and atomic force microscopy. Thermogravimetric analysis, differential scanning calorimetry, and stress–strain tests were used to measure the performance of the films. The results indicate that the glass‐transition temperatures and decomposition temperatures of the hybrid films increased with increasing silica content, whereas the tensile strength had a maximum with the variety of silica contents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2210–2214, 2003

New PI-Silica Hybrids Via Sol-Gel Process for Thin Film Dielectric Materials

Abstract A new class of polyimide-silica hybrid materials for thin film microelectronics were successfully prepared by the sol-gel reaction of tetraethoxysilane (TEOS) in the solution of polyimide precursor in N.N′-dimethylformamide. The composite films were obtained by the hydrolysis and polycondensation of TEOS in the polyimide precursor solution, followed by heating at 270 °C. The chemical structures of polyimide-silica hybrid films were characterized by analytical techiques. X-ray diffraction showed that the polyimide-silica hybrid material has an amorphous structure. The hybrid material was quite stable at elevated temperatures (> 400 °C), with the associated weight loss of 10 wt % only around 600 °C. The dielectric constant of the polyimide-silica (50 wt%) composite measured by ellipsometry was 3.935 to 3.885 as a function of frequency in the range of 1kHz to 20kHz.

Formation of Interconnected Globular Structure of Silica Phase in Polyimide-Silica Hybrid Films Prepared by the Sol-Gel Process

Formation of Interconnected Globular Structure of Silica Phase in Polyimide-Silica Hybrid Films Prepared by the Sol-Gel Process

Feature article. Preparation of new polyimide–silica hybrid materials via the sol–gel process

Download options Please wait... Article information DOI https://doi.org/10.1039/JM9920200679 Article type Paper Download Citation J. Mater. Chem., 1992,2, 679-689 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Feature article. Preparation of new polyimide–silica hybrid materials via the sol–gel process A. Morikawa, Y. Iyoku, M. Kakimoto and Y. Imai, J. Mater. Chem., 1992, 2, 679 DOI: 10.1039/JM9920200679 To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Search articles by author Atsushi Morikawa Yoshitake Iyoku Masa-Aki Kakimoto Yoshio Imai

Preparation of a New Class of Polyimide-Silica Hybrid Films by Sol-Gel Process

A new class of polyimide-silica hybrid films were successfully prepared by the sol-gel reaction starting from tetraethoxysilane (TEOS) in the solution of polyamic acid in N,N-dimethylacetamide. The hybrid films were obtained by the hydrolysis-polycondensation of TEOS in the polyamic acid solution, followed by heating at 270°C. Fairly flexible films were obtained up to 70 wt% of silica content. The films containing the silica less than 8 wt% were yellow and transparent, whereas the films with higher silica content were yellow and opaque. The density of the silica in the hybrid films was estimated to be 1.65 gcm−3. The 29Si nuclear magnetic resonance spectrum indicated that the silica in the films consisted of non-hydroxy, monohydroxy, and dihydroxy siloxane structures. Silica particles with diameter of around 5 μm were observed in the hybrid films by scanning electron microscopy. The density, decomposition temperature, and modulus of the hybrid films increased with increasing the silica content, whereas the tensile strength and elongation at break of the films decreased in this order. The glass transition temperature of the hybrid films showed the minimum at 8 wt% of silica content. The linear thermal expansion coefficient of the silica in the hybrid films was estimated to be 1.3×10−5 K−1.

Preparation of Polyimide-Silica Hybrid Films Using Sol-Gel Process.

Preparation of Polyimide-Silica Hybrid Films Using Sol-Gel Process.