A systematic study of the relationship between the high-frequency dielectric dissipation factor and water adsorption of polyimide films

Abstract

Low dissipation factor (Df) at high-frequency is crucial for the applications of dielectric materials in next generation mobile communication. However, the relationship between the high-frequency Df and the molecular structure...

Preparation of fluorinated polyimides with low dielectric constants and low dielectric losses by combining ester groups and triphenyl pyridine structures

“…4(a), it can be seen that the water absorption of the resulting PIs is in the range of 0.94–0.73%, with PI-E2CF 3 exhibiting the lowest absorption (0.73%), which is much lower than that of commercial PIs (1.5%). 21 The contact angle results in Fig. 4(b) show that the contact angles of the PI films are all greater than 77°, with PI-E2CF 3 having a contact angle as high as 97°.…”

“…Hygroscopicity is one of the critical factors affecting the application value of interlayer dielectric materials. 21,28,30 In the natural state, water molecules with larger D k can easily enter into the PI film to increase the D k of the material, thus affecting signal conduction at high frequencies. The PIs were tested for water absorption and contact angle, and the test results are shown in Fig.…”

“…Previous research in the literature has found that new resins with low D k and low D f can be obtained by reducing the dipole content of the resin and restricting the dipole motion. 20–22 Hence, an attempt is made in this paper to superimpose the combined modification effects of bulky triphenyl pyridine structures, a long-chain ester-based structure, and low-polarity trifluoromethyl structures with the expectation of preparing novel PIs with low D k and low D f at high frequencies and investigating the correlation between their microstructures and macroscopic performances. Firstly, three bulk diamine monomers (BPAB, PBAB3F, PBAB6F) containing triphenyl pyridine structures with different fluorine contents were designed and synthesized based on the research foundation in the laboratory and polymerized with homemade long-chain ester-based anhydride 2,2-propylenebis-4,1-phenylene 1,3-dihydro-1,3-dioxo-5-isobenzofuran carboxylic acid ester (BTPDA) to obtain three novel PIs with different fluorine contents (PI-EH, PI-ECF 3 , PI-E2CF 3 ).…”

Preparation of fluorinated poly(benzoxazole-co-imide) with low dielectric constants based on the thermal rearrangement reaction of o-hydroxy polyimides

“…holes) can accelerate the diffusion of water molecules and improve the contact area with water molecules. 41 To investigate the effect of thermal rearrangement reaction on the hygroscopicity of PBO- X , the water absorption test (as in Fig. 7(a)) and contact angle test (as in Fig.…”

Relationship among the Water Adsorption, Polymer Structure, and High-Frequency Dissipation Factor: Precise Analysis of Water Adsorption of Low-Dielectric Constant Polyimide Films

“…Based on our recent study, we believe that the differences in the dissipation factor with humidity are mainly due to the differences in water adsorption . To this end, we used the “gravimetric method” and the “volumetric method” to study the water adsorption of the PI films at different humidity levels (Figures , S2, Tables S5 and S6).…”