Mechanical enhancer additives for low dielectric films

A process for making a porous organosilicate glass film having a dielectric constant of 3.0 or less and a C/Si ratio of 1 or less, the process comprising:

• providing within a plasma enhanced chemical vapor deposition reaction chamber a substrate and a mixture comprising:
• a first silicon-containing precursor comprising from 3 to 4 Si—O bonds per Si atom, from 0 to 1 of a bond selected from a group consisting of Si—H, Si—Br, and Si—Cl bonds per Si atom, and no Si—C bonds;
• a second silicon-containing precursor comprising at least one Si—C bond per Si atom;
• and a hydrocarbon porogen, wherein the hydrocarbon porogen is plasma-polymerizable and is selected from the group consisting of:
• (a) at least one cyclic hydrocarbon having a cyclic structure and the formula CnH2n, where n is a number ranging from 4 to 14, a number of carbons in the cyclic structure ranging from 4 to 10, and the at least one cyclic hydrocarbon optionally contains a plurality of simple or branched hydrocarbons substituted onto the cyclic structure;
• (b) at least one linear or branched, saturated, singly or multiply unsaturated hydrocarbon of the general formula CnH(2n+2)+2y where n is a number ranging from 2 to 20 and where y is a number ranging from 0 to n;
• (c) at least one singly or multiply unsaturated cyclic hydrocarbon having a cyclic structure and the formula CnH2n−2x, where x is a number of unsaturated sites, n is a number ranging from 4 to 14, a number of carbons in the cyclic structure ranging from 4 to 10, and the at least one singly or multiply unsaturated cyclic hydrocarbon optionally contains a plurality of simple or branched hydrocarbons substituents substituted onto the cyclic structure, and contains endocyclic unsaturation or unsaturation on one of the hydrocarbon substituents;
• (d) at least one bicyclic hydrocarbon having a bicyclic structure and the formula CnH2n−2, where n is a number ranging from 4 to 14, a number of carbons in the bicyclic structure ranging from 4 to 12, and the at least one bicyclic hydrocarbon optionally contains a plurality of simple or branched hydrocarbons substituted onto the bicyclic structure;
• (e) at least one multiply unsaturated bicyclic hydrocarbon having a bicyclic structure and the formula CnH2n−(2+2x), where x is a number of unsaturated sites, n is a number ranging from 4 to 14, a number of carbons in the bicyclic structure ranging from 4 to 12, and the at least one multiply unsaturated bicyclic hydrocarbon optionally contains a plurality of simple or branched hydrocarbons substituents substituted onto the bicyclic structure, and contains endocyclic unsaturation or unsaturation on one of the hydrocarbon substituents;
• and
• (f) at least one tricyclic hydrocarbon having a tricyclic structure and the formula CnH2n−4, where n is a number ranging from 4 to 14, a number of carbons in the tricyclic structure ranging from 4 to 12, and the at least one tricyclic hydrocarbon optionally contains a plurality of simple or branched hydrocarbons substituted onto the cyclic structure;
• applying plasma energy to the mixture in the reaction chamber to induce a polymerization reaction and deposit a film on the substrate, wherein the film comprises a structure-former phase formed by the polymerization reaction of the silicon-containing precursors and a pore-former phase formed by the polymerization reaction of the hydrocarbon porogen;
• and
• treating the deposited film with at least one energy source selected from thermal, photon, electron, plasma, microwave, and chemical energy to remove at least a portion of the pore-former phase and provide the porous organosilicate glass film.

A process for making an organosilicate glass film having a dielectric constant of 4.0 or less, the process comprising:

• providing a silicon-containing mixture that is one selected from the following:
• a mixture (i) comprising a first silicon-containing precursor that comprises from 3 to 4 Si—O bonds per Si atom, from 0 to 1 of a bond selected from the group consisting of Si—H, Si—Br, or Si—Cl bonds per Si atom, and no Si—C bonds, and a second silicon-containing precursor that comprises at least one Si—C bond per Si atom;
• and a mixture (ii) comprising an asymmetric silicon-containing precursor having a number ratio of Si—C bonds to Si atoms that is less than 1;
• adding a hydrocarbon porogen to the silicon-containing mixture;
• introducing the silicon-containing mixture and the hydrocarbon porogen into a reaction chamber having a substrate contained therein;
• and
• applying plasma energy to the mixture in the reaction chamber to induce a polymerization reaction and deposit the organosilicate glass film on the substrate by chemical vapor deposition, wherein the organosilicate glass film comprises a structure-former phase formed by the polymerization reaction of the silicon-containing mixture and a pore-former phase formed by the polymerization reaction of the hydrocarbon porogen.