Low-k dielectric functional imprinting materials

Abstract

In a substantially planar circuit, the conductors are separated by an inorganic material with a dielectric constant of less than about 3.0. The dielectric layers are formed in a process that includes defining trenches and / or vias for the conductors by imprinting an initially planar layer of a radiation curable composition. The imprinting die is preferably UV transparent such that the composition is UV cured while the imprint die is in place. The curable composition includes an organic modified silicate compound and a second decomposable organic component, the latter forming nanometer scale pores as the organic compounds are subsequently decomposed to provide a polysilicate matrix. The pores reduce the effective dielectric constant from that of otherwise dense silicon dioxide.

Description

BACKGROUND OF INVENTION [0001] The present invention relates to a method or material of fabricating integrated circuits, and in particular to a method of forming an integrated circuit on a substrate having a low dielectric constant. [0002] There is a continuing desire in the microelectronics industry to increase the circuit density in multilevel integrated circuit devices, e.g., memory and logic chips, thereby increasing their performance and reducing their cost. In order to accomplish this goal, it is also desirable to reduce the minimum feature size on the chip, e.g., circuit line width, and also to decrease the dielectric constant of the interposed dielectric material to enable closer spacing of circuit lines without an increase in crosstalk and capacitive coupling. Further, there is a desire to reduce the dielectric constant of the dielectric materials such as utilized in the back end of the line (BEOL) portion of integrated circuit devices, which contain input / output circuitry,...

AI Technical Summary

Benefits of technology

[0013] As the UV curing is preferably conducted through a mold that is UV transparent, another object of achieving a robust process for imprinting includes using a UV curable polymerizable fluid that includes an organic modified silicate, a decomposable organic compound, and a fluorosurfactant to improve the release of the cured composition from the imprint-molding tool.

Problems solved by technology

However, the development of appropriate organic polymers, as well as their depositions and patterning methods poses significant challenges.

The selection or choice of an organic material is frequently limited by the need for higher temperature steps in other aspects of the process, such as metallization or semiconductor fabrication.

Although porous inorganic materials can inherently withstand higher processing temperatures, like other dielectric materials, additional challenges arise due to the complexity of the patterning processes.

However, photolithography has inherent size limitations that demand the use of shorter wavelength sources and more sophisticated optics to reduce the line width and feature sizes in the micro circuitry.

The plurality of required processing steps inherently increases the processing time, resulting in higher costs as well as generally reduced product yield.

Images