Method for preparing low K material and film thereof

摘要

A method for preparing a low dielectric constant (low k) material and a film thereof is provided. The method includes the following steps. A substrate is first put into a plasma generating reaction system, and a carrier gas carrying a carbon and fluorine containing silicon dioxide precursor is then introduced into the plasma generating reaction system, so that the carbon and fluorine containing silicon dioxide precursor is formed on the substrate. After that, the carbon and fluorine containing silicon dioxide precursor is converted to a low k material film through heating; meanwhile, a stress of the low k material film is eliminated such that the film has a more compact structure. By means of these steps the carbon and fluorine containing silicon dioxide precursor is still capable of forming a low k material film of silicon dioxide containing a large amount of fluorocarbon, even under various different atmospheres.

主权项

1. A method for preparing a low dielectric constant (low k) material film, comprising:
putting a substrate into a plasma generating reaction system, wherein a first temperature in the plasma generating reaction system ranges from 100 to 300° C.; heating a single silicon dioxide precursor comprising carbon and fluorine disposed in an evaporator to a second temperature ranging from 50 to 100° C. to be a gaseous phase with a vapor pressure in the range of 30 to 80 torr; introducing a carrier gas, carrying the single silicon dioxide precursor comprising carbon and fluorine alone, into the plasma generating reaction system, and forming the silicon dioxide precursor comprising carbon and fluorine on the substrate, wherein the carrier gas is one selected from oxygen and argon; and converting the silicon dioxide precursor comprising carbon and fluorine into a low k material film with fluorocarbon long chains consisting of a C—Fx bond, and eliminating a stress of the low k material film through a thermal treatment by providing an additional energy to the silicon dioxide precursor comprising carbon and fluorine, so that the low k material film has a compact structure; wherein the silicon dioxide precursor comprising carbon and fluorine is R1Si(OR2) (OR3) (OR4), tridecafluoro-1,1,2,2-tetrahydrooctyl-triethoxysilane (TDF-TEOS), and trimethoxy (3,3,3-trifluoropropyl) silane, in which R1 is one of fluoroalkyl, fluoroalkenyl, fluoroalkynyl and fluoroaryl, and R2, R3 and R4 are one of alkyl, methyl, ethyl, aryl, alkenyl and alkynyl; a carbon atom ratio content of the low k material film ranges from 10 to 50% and a fluorine atom ratio content ranges from 10 to 40%.