Kaikai Jin

Non‐Porous Low‐k Dielectric Films Based on a New Structural Amorphous Fluoropolymer

A non-porous and amorphous fluoropolymer PFN with low dielectric constant of 2.33 and dielectric loss less than 1.2 × 10(-3) is reported here. PFN also exhibits good mechanical properties and high thermostability. This study is a new example of a fully dense material showing a low k value and having good thermo/mechanical properties.

A novel one-pot synthesized organosiloxane: synthesis and conversion to directly thermo-crosslinked polysiloxanes with low dielectric constants and excellent thermostability

A novel organosiloxane containing a thermally cross-linkable benzocyclobutene group was successfully synthesized through a one-pot Grignard reaction procedure. The organosiloxane can be easily polymerized or copolymerized to form the oligomers which can be directly converted to cross-linked network structures with excellent thermostability and low dielectric constants, implying that the organosiloxane has potential application in the electrical and microelectronics industry.

Postpolymerization of a Fluorinated and Reactive Poly(aryl ether): An Efficient Way To Balance the Solubility and Solvent Resistance of the Polymer

A new fluorinated poly(aryl ether) with reactive benzocyclobutene groups as the side chain was successfully synthesized. This polymer showed a number-average molecular weight (Mn) of 200,000 and had good solubility and film-forming ability. After being postpolymerized at high temperature (>200 °C), the polymer film converted to a cross-linked network structure, which was insoluble in the common organic solvents. Such results suggest that the postpolymerization is an efficient way to achive the balance between the solubility and the solvent resistance of the polymer. TGA data showed that the postpolymerized polymer had a 5 wt % loss temperature at 495 °C and a residual of 61% at 1000 °C under N2. The cross-linked film also exhibited good dielectric properties with an average dielectric constant of about 2.62 in a range of frequencies from 1 to 30 MHz. With regard to the mechanical properties, the cross-linked film had hardness, Youngs modulus, and bonding strength to a silicon wafer of 1.22, 8.8, and 0.89 GPa, respectively. These data imply that this new polymer may have potential applications in the electrical and microelectronics industry.

Benzocyclobutene resin with fluorene backbone: a novel thermosetting material with high thermostability and low dielectric constant

A fluorene-based monomer (FB) with thermally cross-linkable benzocyclobutene groups is reported here. This monomer showed good solubility in the common organic solvents and had a low melting point (128 °C). When being treated at high temperature (>200 °C), the monomer was converted to a cross-linked network structure (PFB). TGA data exhibited that PFB had high thermostability with a 5% weight loss temperature of 437 °C and 372 °C in N2 and air, respectively. Moreover, PFB showed a char yield of 47.6% at 1000 °C in N2. With regard to the electrical properties, PFB indicated an average of dielectric constants of about 2.7 ranging from 0.15 MHz to 30 MHz. All these results suggest that FB could be used as the varnish for insulating enameled wire in the electrical industry, and as encapsulation resins in the microelectronics industry.

A new low dielectric material with high thermostability based on a thermosetting trifluoromethyl substituted aromatic molecule

A thermally cross-linkable molecule composed of bis(trifluoromethyl)benzene and benzocyclobutene units (F1) was successfully prepared. Heating F1 (>200 °C) gave a cured resin, which showed a dielectric constant (k) of 2.47 at 30 MHz and an average k value of less than 2.51 in a range of frequencies from 0.15 MHz to 30 MHz. Such low k values are comparable to other polymeric low-k materials. For comparison, a perfluorobenzene with benzocyclobutene groups (F2) was also synthesized. The cured F2 exhibited an average k value of 2.98, indicating that the introduction of a trifluoromethyl group into the backbone of the molecules can efficiently decrease the dielectric constant of the molecules. The cured F1 also exhibited high thermostability (T5 = 429 °C, weight residual = 47.7% at 1000 °C under N2). These results suggest that F1 is suitable for the utilization in ultra large scale integration circuits.

Fluorinated and Thermo-Cross-Linked Polyhedral Oligomeric Silsesquioxanes: New Organic–Inorganic Hybrid Materials for High-Performance Dielectric Application

A fluorinated and thermo-cross-linked polyhedral oligomeric silsesquioxane (POSS) has been successfully synthesized by thermal polymerization of a fluorinated POSS monomer having an inorganic silsesquioxane core and organic side chains bearing thermo-cross-linkable trifluorovinyl ether groups. This new inorganic-organic hybrid polymer shows high thermostability with a 5 wt % loss temperature of 436 °C, as well as good transparency (a sheet with an average thickness of 1.5 mm shows high transmittance of 92% varying from 400 to 1100 nm). Moreover, the polymer exhibits both low dielectric constant (<2.56) and low dissipation factor (<3.1 × 10-3) in a wide range of frequencies from 40 Hz to 30 MHz even at a high frequency of 5 GHz. The polymer also shows low water uptake (<0.04%) and low Dk (near 2.63) after immersing it in water at room temperature for 3 days. These data imply that this polymer is very suitable to be utilized as a high-performance dielectric material for fabrication of high-frequency printed circuit boards or encapsulation resins for integrated circuit dies in the microelectronic industry. Furthermore, this work also provides a route for the preparation of fluorinated POSS-based polymers.

Dendrimeric organosiloxane with thermopolymerizable –OCFCF2 groups as the arms: synthesis and transformation to the polymer with both ultra-low k and low water uptake

A novel fluoro-containing dendrimeric macromolecule with cyclic siloxane as the core and aryl-trifluorovinyl-ether (–OCFCF2) units as the arms was reported. The macromolecule was easily converted to a cross-linked structure showing an ultra-low k value and low water uptake. In particular, the network also exhibited high thermostability and excellent transparency.

Propargyl ether-functionalized poly(m-phenylene): a new precursor for the preparation of polymers with high modulus and high Tg

A propargyl ether-functionalized poly(m-phenylene) (PE-PMP) is reported here. This polymer exhibits good solubility and film-forming ability. After postpolymerization at high temperature, the polymer transforms to a cross-linked network, which shows high thermostability with a 5% weight loss temperature at 471 °C and a char yield of 67% at 1000 °C under N2. Thermo-mechanical analysis (TMA) reveals that the cured polymer shows an average linear coefficient of thermal expansion (CTE) of 30.6 ppm °C−1 ranging from 30 to 300 °C and a glass transition temperature (Tg) near 330 °C. Moreover, even at temperatures up to 300 °C, the cured polymer possesses a storage modulus exceeding 4.0 GPa. These data are superior to those of the commercial epoxy and novolac resins and polyimides. Furthermore, the cured polymer film has good mechanical properties with hardness, Youngs modulus and a bonding strength to a silicon wafer of 1.22, 9.44 and 0.78 GPa, respectively. The cured polymer film also shows good dielectric properties with an average dielectric constant of 2.93 in a range of frequencies from 2 MHz to 30 MHz. Such results suggest that the polymer is a useful precursor for preparation of insulating materials with high modulus and Tg in the microelectronics industry.

A new polymer with low dielectric constant based on trifluoromethyl-substituted arene: preparation and properties

A new polymer with low dielectric constant is reported here. This polymer contains a trifluoromethyl-substituted phenyl unit and a binaphthyl unit, and shows high thermostability with a glass transition temperature of 244 degrees C and a 5 wt% loss at temperature 518 degrees C under nitrogen. The polymer also exhibits good film-forming ability, and the formed films exhibit high hydrophobicity with a contact angle of 103.6 degrees with water. In a range of frequencies from 1 to 25 MHz, the polymer reveals an average dielectric constants of about 2.56. In regard to the mechanical properties, the polymer film shows an average hardness of 0.37 GPa and a Youngs modulus of 15.07 GPa. These results indicate that the polymer could be used as a varnish for enameled wire, sizing agents for high-performance carbon fiber, and the matrix resin for the production of laminated composites utilized in the printed-circuit-board (PCB) industry.

Post-functionalization of novolac resins by introducing thermo-crosslinkable –OCFCF2 groups as the side chains: a new strategy for production of thermosetting polymers without releasing volatiles

Post-functionalization of a commercial novolac resin by introducing thermo-crosslinkable trifluorovinylether groups as the side chains offers a new polymer, which can form a cross-linked network without releasing volatiles during thermal curing. The cured resin shows a lower dielectric constant and higher thermostability than those of most commercial novolac resins.