Recovery of hydrophobicity of low-k and ultra low-k organosilicate films used as inter metal dielectrics
First Claim
1. A method for restoring properties of a low k or very low dielectric constant organosilicate film having hydrogen atoms or alkyl or aryl groups attached to silicon atoms, and used in a low or very low dielectric constant insulating layer in a semiconductor chip, or chip carrier, or a semiconductor wafer wherein said organosilicate film has undergone processing tending to degrade the properties, the method comprising:
- applying to the film a silylating agent comprising an aminosilane, so as to restore dielectric properties of the film, wherein the aminosilane has the general formula (R2N)xSiR′
YR″
Z where X, Y and Z are integers with x varying from 1 to 3, and Y and Z varying from 3 to 0 respectively but where x+y+z is always equal to 4, and where R, R′
, and R″
are any hydrogen, methyl, aryl, allyl, phenyl or vinyl moiety.
3 Assignments
0 Petitions
Accused Products
Abstract
Often used to reduce the RC delay in integrated circuits are dielectric films of porous organosilicates which have a silica like backbone with alkyl or aryl groups (to add hydrophobicity to the materials and create free volume) attached directly to the Si atoms in the network. Si—R bonds rarely survive an exposure to plasmas or chemical treatments commonly used in processing; this is especially the case in materials with an open cell pore structure. When Si—R bonds are broken, the materials lose hydrophobicity, due to formation of hydrophilic silanols and low dielectric constant is compromised. A method by which the hydrophobicity of the materials is recovered using a novel class of silylation agents which may have the general formula (R2N)XSiR′Y where X and Y are integers from 1 to 3 and 3 to 1 respectively, and where R and R′ are selected from the group of hydrogen, alkyl, aryl, allyl and a vinyl moiety. Mechanical strength of porous organosilicates is also improved as a result of the silylation treatment.
55 Citations
79 Claims
-
1. A method for restoring properties of a low k or very low dielectric constant organosilicate film having hydrogen atoms or alkyl or aryl groups attached to silicon atoms, and used in a low or very low dielectric constant insulating layer in a semiconductor chip, or chip carrier, or a semiconductor wafer wherein said organosilicate film has undergone processing tending to degrade the properties, the method comprising:
applying to the film a silylating agent comprising an aminosilane, so as to restore dielectric properties of the film, wherein the aminosilane has the general formula (R2N)xSiR′
YR″
Z where X, Y and Z are integers with x varying from 1 to 3, and Y and Z varying from 3 to 0 respectively but where x+y+z is always equal to 4, and where R, R′
, and R″
are any hydrogen, methyl, aryl, allyl, phenyl or vinyl moiety.- View Dependent Claims (2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40)
- 3. A method as recited in 1, wherein the processing includes etching of the film, and removing a photresist material from the film, wherein the silylating agent is applied after the etching and the removing.
-
41. A method for restoring properties of a low k or very low dielectric constant organosilicate film having hydrogen atoms or alkyl or aryl groups attached to silicon atoms, and used in a low or very low dielectric constant insulating layer in a semiconductor chip, or chip carrier, or a semiconductor wafer wherein said organosilicate film has undergone processing tending to degrade the properties, the method comprising:
applying to the film a silylating agent comprising an aminosilane, so as to restore dielectric properties of the film, wherein the aminosilane has the general formula (R2N)xSiR′
Y where X and Y are integers from 3 to 2 and 1 to 2 respectively, and where R and R″
are selected from the group consisting of hydrogen, alkyl, aryl, allyl, phenyl and a vinyl moiety.- View Dependent Claims (44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79)
- 42. A method as recited in 41, wherein the processing includes etching of the film, and removing a photresist material from the film, wherein the silylating agent is applied after the etching and the removing.
Specification