Structural and dielectric properties of some epiclon-based polyimide films

AbstractSurface and electrical properties of two flexible and cross-linked epiclon based polyimide films were investigated. Surface tension measurements indicate an increased hydrophobicity due to both isothermal treatment - which induces imidization and cross-linking - and to the chemical structure, characterized by the different number of ether linkages in the polyimide backbone. Morphology of film surfaces, modified by plasma treatment, shows high roughness and, implicitly, improved adhesion, as required in electronics. The studied polyimides exhibit low dielectric constants and dielectric losses, comparatively to conventional aromatic polyimides. The electrical conductance and resistivity characteristics of these polymers recommend them as good insulators for dielectric layers in microelectronic applications.

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Investigation of the Chemical Structure of Ultra-Thin Polyimide Substrate for the Xenon Flash Lamp Lift-off Technology

Polymers ◽

10.3390/polym13040546 ◽

2021 ◽

Vol 13 (4) ◽

pp. 546

Author(s):

Seong Hyun Jang ◽

Young Joon Han ◽

Sang Yoon Lee ◽

Geonho Lee ◽

Jae Woong Jung ◽

...

Keyword(s):

Flexible Electronics ◽

Chemical Structure ◽

Surface Characteristics ◽

Dielectric Constants ◽

Flash Lamp ◽

Next Generation ◽

Polyimide Films ◽

Chemical Structures ◽

Polyimide Substrate ◽

Lift Off

Lift-off is one of the last steps in the production of next-generation flexible electronics. It is important that this step is completed quickly to prevent damage to ultrathin manufactured electronics. This study investigated the chemical structure of polyimide most suitable for the Xe Flash lamp–Lift-Off process, a next-generation lift-off technology that will replace the current dominant laser lift-off process. Based on the characteristics of the peeled-off polyimide films, the Xe Flash lamp based lift-off mechanism was identified as photothermal decomposition. This occurs by thermal conduction via light-to-heat conversion. The synthesized polyimide films treated with the Xe Flash lamp–Lift-Off process exhibited various thermal, optical, dielectric, and surface characteristics depending on their chemical structures. The polyimide molecules with high concentrations of –CF3 functional groups and kinked chemical structures demonstrated the most promising peeling properties, optical transparencies, and dielectric constants. In particular, an ultra-thin polyimide substrate (6 μm) was successfully fabricated and showed potential for use in next-generation flexible electronics.

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Polyimide Nanofoams For Low Dielectric Applications

MRS Proceedings ◽

10.1557/proc-381-79 ◽

1995 ◽

Vol 381 ◽

Cited By ~ 30

Author(s):

K. R. Carter ◽

H. J. Cha ◽

R. A. Dipietro ◽

C. J. Hawker ◽

J. L. Hedrick ◽

...

Keyword(s):

Thin Film ◽

High Thermal Stability ◽

Dielectric Constants ◽

Dispersed Phase ◽

Foam Formation ◽

Density Measurements ◽

Low Dielectric ◽

Microelectronic Devices ◽

Dielectric Layers ◽

Film Dielectric

AbstractFoamed polyimides have been developed in order to obtain thin film dielectric layers with very low dielectric constants for use in microelectronic devices. In these systems the pore sizes are in the nanometer range, thus, the term “nanofoam”. The polyimide foams are prepared from block copolymers consisting of thermally stable and thermally labile blocks, the latter being the dispersed phase. Foam formation is effected by thermolysis of the thermally labile block leaving pores the size and shape corresponding to the initial copolymer morphology. Nanofoams prepared from a number of polyimides as matrix materials, were investigated as well as a number of thermally labile polymers. The foams were characterized by a variety of experiments including, TEM, SAXS, WAXD, DMTA, density measurements, refractive index measurements and dielectric constant measurements. Thin film foams, with high thermal stability and dielectric constants approaching 2.0, can be prepared using the copolymer/nanofoam approach.

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A methodology for the preparation of nanoporous polyimide films with low dielectric constants

Thin Solid Films ◽

10.1016/j.tsf.2005.12.216 ◽

2006 ◽

Vol 510 (1-2) ◽

pp. 241-246 ◽

Cited By ~ 44

Author(s):

Lizhong Jiang ◽

Jiugui Liu ◽

Dezhen Wu ◽

Hangquan Li ◽

Riguang Jin

Keyword(s):

Dielectric Constants ◽

Polyimide Films ◽

Low Dielectric

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Nanoporous Polyimide Films from Polyimide-Aliphatic Polyester or Polyimide-Aliphatic Polycarbonate Copolymers

MRS Proceedings ◽

10.1557/proc-431-487 ◽

1996 ◽

Vol 431 ◽

Cited By ~ 4

Author(s):

K. R. Carter ◽

J. L. Hedrick ◽

R. Richter ◽

P. T. Furuta ◽

D. Mecerreyes ◽

...

Keyword(s):

Ring Opening ◽

Dielectric Constants ◽

Foam Formation ◽

Aliphatic Polyester ◽

Trimethylene Carbonate ◽

Polyimide Films ◽

Low Dielectric ◽

Microelectronic Devices ◽

Aliphatic Polycarbonate ◽

Film Dielectric

AbstractWe have explored polyimide foams created using a block copolymer approach as part of our research efforts to obtain thin film dielectric layers with very low dielectric constants for use in microelectronic devices. In these systems the pore sizes are in the nanometer range thus the term “nanofoam”, The polyimide foams are prepared from phase separated block copolymers consisting of thermally stabile and thermally labile blocks, the latter being the dispersed phase. Foam formation is effected by thermolysis of the labile block leaving pores the size and shape corresponding to the initial copolymer morphology. Polyimide nanofoams generated from thermolysis of polyimidealiphatic polyester and polyimide-aliphatic polycarbonate copolymers were investigated. The aliphatic co-blocks were synthesized by ring opening polymerization of the cyclic monomers, such as E-caprolactone, valerolactone, trimethylene carbonate, and L-lactide. The aliphatic blocks were designed in such a way as to allow for incorporation into polyimide copolymers. The foams were characterized by a variety of techniques including, TEM, SAXS, WAXD, DMTA, density and refractive index measurements.

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An Interesting Result of Dielectric Property for Novel Polyimides with Fluorene Groups

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.511 ◽

2010 ◽

Vol 663-665 ◽

pp. 511-514 ◽

Cited By ~ 2

Author(s):

Yuan Yuan ◽

Bing Xie ◽

Yu Wang

Keyword(s):

Thin Film ◽

Thin Films ◽

Mechanical Properties ◽

Dielectric Property ◽

Dielectric Constants ◽

The Other ◽

Polyimide Films ◽

Low Dielectric ◽

High Dielectric ◽

Biphenyltetracarboxylic Dianhydride

A series of polyimide thin films were prepared successfully based on bis[3,5-dimethyl-4- (4-aminophenoxy)phenyl]methane （BDAPM）, 9,9-bis（4-（4-aminophenoxy）phenyl）fluorene (BAOFL) and different dianhydrides. And an interesting result of dielectric property for polyimide thin films was found that the polyimide thin film prepared with 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) exhibited high dielectric constants of 5.7 at 1MHz. Conversely, the other polyimides possessing fluorene groups showed low dielectric constants. The structures and the mechanical properties of polyimide films also proved the reason for results of dielectric properties.

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Effects of chemical structure on the electrical properties of some polymers with imidic structure

e-Polymers ◽

10.1515/epoly.2007.7.1.793 ◽

2007 ◽

Vol 7 (1) ◽

Cited By ~ 2

Author(s):

Andreea Irina Cosutchi ◽

Camelia Hulubei ◽

Manuela Buda ◽

Toni Botila ◽

Silvia Ioan

Keyword(s):

Electrical Properties ◽

Chemical Structure ◽

Electrical Conductance ◽

Polymeric Materials ◽

Dissipation Factor ◽

Amic Acid ◽

Dielectric Constants ◽

Frequency Range ◽

The Relationship ◽

Azobenzene Groups

AbstractThe electrical properties of two types of imidic polymers, i.e. copolymaleimides containing azobenzene groups and epiclon-based polyimides with their corresponding poly(amic acid)s, have been investigated. The dielectric constant and electrical conductance were experimentally measured over the 1-100 KHz frequency range. Also, the dielectric constants for all samples were determined from the experimentally and theoretically evaluated refractive indices at optical frequencies, when Maxwell’s relationship can be applied. From the currentvoltage characteristic I(U), electrical resistance can be determined, providing information on the relationship between the nature of the material and its electric properties. The obtained values show that epiclon-based polyimides and copolymaleimides present higher electrical resistivity than the poly(amic acid)s. The dissipation factor was evaluated, revealing low energy loss under the form of heat in the studied dielectrics. These results show that these polymeric materials are good insulators, which recommends them for microelectronic applications.

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Highly transparent, strong, and flexible fluorographene/fluorinated polyimide nanocomposite films with low dielectric constant

Journal of Materials Chemistry C ◽

10.1039/c8tc00998h ◽

2018 ◽

Vol 6 (24) ◽

pp. 6378-6384 ◽

Cited By ~ 32

Author(s):

Xiaodong Yin ◽

Yiyu Feng ◽

Qiang Zhao ◽

Yu Li ◽

Shuangwen Li ◽

...

Keyword(s):

Dielectric Constant ◽

Dielectric Constants ◽

Nanocomposite Films ◽

Low Dielectric Constant ◽

Polyimide Films ◽

Low Dielectric ◽

Fluorinated Polyimide ◽

Polyimide Nanocomposite

Transparent and flexible fluorinated polyimide films with loading of well-dispersed fluorographene exhibit low dielectric constants.

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Insoluble, Low Dielectric Polyimides

MRS Proceedings ◽

10.1557/proc-214-131 ◽

1990 ◽

Vol 214 ◽

Author(s):

Diane M. Stoakleya ◽

Anne K. St. Clair

Keyword(s):

Dielectric Constants ◽

Structure Property ◽

Polyimide Films ◽

Electronic Interactions ◽

Excellent Thermal Stability ◽

Low Dielectric ◽

Structure Property Relationships ◽

Enhanced Solubility ◽

Hydraulic Fluids ◽

Image Position

ABSTRACTStudies have been conducted at NASA Langley establishing structure-property relationships in polyimides that provide a means of lowering dielectric constants by reducing chain-chain electronic interactions and by incorporation of fluorine into the polymer molecular structure. The resulting polyimides exhibit excellent thermal stability and mechanical strength, improved resistance to moisture and enhanced solubility. Most polyimides containing fluorine in only one monomer are at least partially soluble in common organic solvents, and polyimides containing fluorine in both the dianhydride and the diamine are fully soluble. Although this enhanced solubility aides processability and is desirable for many applications, it is a severe disadvantage for aircraft applications where exposure to hydraulic fluids and other chemicals is likely to occur. This work involves the development of insoluble, low dielectric polymers prepared from 2, 2-bis[4-(3, 4-dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride (BFDA) and selected fluorine-containing diamines.BFDA-containing polyimide films had dielectric constants that ranged from 2.44 to 2.53 at 10 GHz and exhibited insolubility in solvents including N, N-dimethylacetamide, chloroform, diglyme and N-methylpyrrolidinone.

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