The often observed decrease in relative permittivity (e‘) and refractive index (n) that accompanies fluorine substitution is the result of several effects. Fluorine replacement for hydrogen is known to decrease local electronic polarization and is thought to frequently increase fractional free volume. Both of these effects can independently decrease e‘ and n, and this paper attempts to assign the observed decreases between these mechanisms for a series of hydrogen/fluorine polyimide analogs.

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

Novel double- and triple-patterning methods are provided. The methods involve applying a shrinkable composition to a patterned template structure (e.g., a structure having lines) and heating the composition. The shrinkable composition is selected to possess properties that will cause it to shrink during heating, thus forming a conformal layer over the patterned template structure. The layer is then etched to leave behind pre-spacer structures, which comprise the features from the pattern with remnants of the shrinkable composition adjacent the feature sidewalls. The features are removed, leaving behind a doubled pattern. In an alternative embodiment, an extra etch step can be carried out prior to formation of the features on the template structure, thus allowing the pattern to be tripled rather than doubled.

Spin-on spacer materials for double- and triple-patterning lithography

High-performance polymers are used in applications demanding service at enhanced temperature while maintaining their structural integrity and an excellent combination of chemical, physical, and mechanical properties. Some of the important polymers in this respect are polyimides, polyamides, and polybenzazoles. However, all of these polymers have a common problem of processing difficulty due to their infusibility and poor solubility in organic solvents. The reasons are strong interchain forces, inherent macromolecular rigidity, or semicrystallinity. A great amount of work has been directed to making polymers more tractable, soluble, and processable without sacrificing their high-performance characteristics. Thus, the last two decades have witnessed the spectacular growth of research in a new polymer type, the one containing hexafluoroisopropylidene (6F) groups. Incorporation of 6F units into the macromolecular chain increases the solubility, thermal stability, flame resistance, glass transition te...

Hexafluoroisopropylidene-Containing Polymers for High-Performance Applications

PURPOSE: A liquid crystal alignment agent, a liquid crystal alignment film using thereof, and a liquid crystal display device including thereof are provided to produce the liquid crystal alignment film capable of obtaining a long-term thermal reliability of the voltage holding ratio at the liquid crystal display device. CONSTITUTION: A liquid crystal alignment agent contains polyamic acid which is a reaction product from a reaction of tetracarboxylic dianhydride and diamine, or its derivative. A liquid crystal alignment film is produced by heating a coating layer of the liquid crystal alignment agent. A liquid crystal display device comprises a pair of substrates, and a liquid crystal molecule, a liquid crystal layer formed in between the substrates, an electrode applying the voltage to the liquid crystal layer, and the liquid crystal alignment film.

Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

Planarization of geometrically difficult semiconductor device surfaces is accomplished utilizing a coating technique in which on an object with a flat surface is used to planarize the coating material. In particular, device processing is accomplished by including a step that produces a planar surface by coating a nonplanar surface with a material that has a viscosity of less than 1000 cp. An object with a flat surface is placed into contact with the material in such a manner that the material is planarized to a desired degree. The material is cured while in contact with the object's flat surface. The object is then separated from the material. The planarity of the planarizing material is then transferred into the underlying layer using conventional techniques.

Device fabrication involving planarization

Polyimide optical waveguide structures comprising a core within a cladding wherein at least one of the core and the cladding is a polyimide containing 6FDA; and the complementary portion of the waveguide structure is a polyimide having partial replacement of the 6FDA of the core or cladding composition by BPDA, and wherein the difference in the birefringence of the core and cladding are less than the difference in the refractive index. Copolyimides containing 6FDA and BPDA moieties, and at least one diamine, which have properties useful in optical applications including adjustable refractive index and controllable birefringence, low optical losses, low optical absorbance, increased solvent resistance, and high thermal stability. A method for adjusting the refractive index to make useful copolyimide core/cladding waveguide structures by controlling the 6FDA/BPDA ratio.

Polymide optical waveguide structures

A wet-etch composition for polyamic acids and partially cured polyamic acids comprising an aqueous solution having a major portion of water, a substituted hydrocarbon solvent and a non-ionic base that is strong enough to deprotonate the polyamic acid or a partially cured polyamic acid in a weight ratio of 0.1-49:49-0.1, with the proviso that the composition contains less than 1.0 percent ionic base. The present invention further provides a process for wet-etching polyamic acids or partially cured polyamic acids.

Wet-etch process and composition

A polyimide layer having a thickness greater than about 5 microns is formed on a substrate by coating a substrate with a solution of polymer and a solvent of the formula ##STR1## wherein R1 and R2 are independently a hydrogen, a C1 to C6 alkyl moiety, or a ##STR2## R5 is a C1 to C6 alkyl moiety; and R3 and R4 are independently hydrogen or a C1 to C6 alkyl moiety, and curing the resulting coated substrate.

Process for making thick multilayers of polyimide

A chemical resistant copolymer useful in electronic applications, said copolymer is a polyimide containing a 3,3',4,4'-tetracarboxybiphenyl dianhydride (BPDA) moiety, at least one other dianhydride moiety, and at least one diamine.

Polyimide copolymers containing 3,3',4,4'-tetracarboxybiphenyl dianhydride (bpda) moieties

A group of polyimides and copolyimides made from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) or 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride (IPAN) their acid or ester forms and selected aromatic diamines are disclosed which are useful for substrate coatings and interlevel dielectrics in on-chip and multi-chip package applications. In such applications these polymers exhibit lower dielectric constant, lower moisture uptake and reduced dielectric constant variation with temperature and humidity than existing polymers, yet they are both thermally stable at required processing temperatures and can form suitably adherent, pinhole-free coatings on electronic component substrates.

Douglas E. Fjare

Papers

Polymide optical waveguide structures

Wet-etch process and composition

Process for making thick multilayers of polyimide

Polyimide copolymers containing 3,3',4,4'-tetracarboxybiphenyl dianhydride (bpda) moieties

Low dielectric constant, low moisture uptake polyimides and copolyimides for interlevel dielectrics and substrate coatings