Influence of Free Volume Change on the Relative Permittivity and Refractive Index in Fluoropolyimides

Hougham, Gareth; Tesoro, Giuliana C.; Viehbeck, A.

doi:10.1021/ma9503423

Cited by 212 publications

(187 citation statements)

References 10 publications

Supporting

Mentioning

181

Contrasting

Order By: Relevance

“…A correlation of high free volume and low dielectric constant has been previously reported for polyimides [8][9][10]. In these investigations positron lifetime spectroscopy and group additivity methods were used to quantify free volume fractions.…”

Section: Free Volumementioning

confidence: 90%

Fundamental insight on developing low dielectric constant polyimides

1997

View full text Add to dashboard Cite

Section: Free Volumementioning

confidence: 90%

Fundamental insight on developing low dielectric constant polyimides

1997

View full text Add to dashboard Cite

“…Different weights of PTS were added to each portion to get PAA± PTS solutions with different weight ratios of PTS to APTS± PAA (8,16,24,36,50,70, 100, 140 w/w%). Stirring was continued at room temperature for 15 h, to give a homogenous solution.…”

Section: Preparation Of Paa±pts Solution and Pi/pssq-like Hybrid ®Lmsmentioning

confidence: 99%

Low dielectric polyimide/poly(silsesquioxane)-like nanocomposite material

Tsai

Whang

2001

Polymer

174

120

View full text Add to dashboard Cite

A new type of low dielectric polyimide/poly(silsesquioxane)-like (PI/PSSQ-like) hybrid nanocomposite material is successfully prepared from the polyimide (ODA±ODPA) precursor containing phenyltrialkoxysilane (PTS) at two chain ends and monoaryltrialkoxysilane with a self-catalyzed sol±gel process. We employ p-aminophenyltrimethoxysilane (APTS) to provide bonding between the PTS and ODPA±ODA phase. It is shown by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) that the PSSQ-like domain sizes with uniform size are fairly well separated in the hybrid ®lms. The silica domain sizes of 5000-PIS and 5000-PIS±50-PTS ®lms are in the range of 30±100 nm, of 5000-PIS±100-PTS and 10000-PIS±100-PTS in the range of 80±200 and 300±600 nm, respectively. The dielectric constant can be 2.79 for 5000-PIS±140-PTS with fairly good mechanical properties. The PI/PSSQ-like hybrid ®lms have higher onset decomposition temperature and char yield in thermogravimetric analysis (TGA) and higher T g in differential scanning calorimetry (DSC) than the pure PI. Moreover, the PI/PSSQ-like hybrid ®lms have excellent transparency even under high PTS content. In the series of X-PIS hybrid ®lms, the coef®cient of thermal expansion (CTE) below T g increases with the PI block chain length, but in the series of X-PIS±y-PTS ®lms, it slightly increases with the PTS content. However, above T g the CTE of X-PIS and X-PIS±24-PTS is much lower than that of the pure PI. The dielectric constant and water absorption of X-PIS±y-PTS ®lms decrease with the PTS content because of the higher free volume and hydrophobicity. q

show abstract

“…Thus, according to literature data [42,43], a higher free volume determines a lower dielectric constant. In Figure 3 it can be observed that dielectric constants of Epiclon-derived PIs containing ether bridges are around 2.8 at 1 MHz, recommending this type of PIs as interlevel dielectric layers in the fabrication of semiconductor chips and multichip packaging structures [44].…”

Section: Refractive Index Optical Gap and Absorption Edgesmentioning

confidence: 77%