Semiconductor device and method of manufacturing the semiconductor device
View Patent ↗A semiconductor device capable of high speed operation with a substantially small interlayer capacitance is produced by steps of using an insulating film comprising an organic insulating film and an insulating film composed of an organometallic polymer material as an interlayer insulating film formed by coating, patterning the insulating film in a semi-thermosetting state, etching the organic insulating film as the lower layer by means of the organometallic polymer as a mask, using a plasma gas containing oxygen as the main component, and then conducting ultimate baking treatment of these insulating films.
1. A semiconductor device comprising a wiring layer and an interlayer insulating film layer, characterized in that the interlayer insulating film layer comprises a first insulating layer composed of an organic insulating film having a relative dielectric constant of 3.5 or less as a lower layer and a second insulating layer composed of an organometallic polymer having a relative dielectric constant of less than 4.0 laid thereon as an upper layer, wherein the organometallic polymer is a ladder silicone-based polymer and the ladder silicone-based polymer is a polymer material having a molecular structure represented by the following formulas (I) or (II):
wherein R is an alkali-soluble group-containing organic group represented by the formula:
in which m is an integer of 1-3; R″ is a hydroxyl group: and a is an integer of 1-3; and n is a positive number of 2 or more for the repeating unit;
wherein R′ is an organic group represented by the formula:
in which R′″ is an alkoxy group having 1 to 3 carbon atoms; and m and n are as defined above.
2. A semiconductor device according to claim 1 , characterized in that the second insulating layer has a thickness as large as or smaller than that of the first insulating layer.
3. An electronic circuit device comprising a wiring layer and an interlayer insulating film layer, characterized in that the interlayer insulating film layer comprises a first insulating layer composed of an organic insulating film having a relative dielectric constant of 3.5 or less as a lower layer and a second insulating layer composed of an organometallic polymer having a relative dielectric constant of less than 4.0 laid thereon as an upper layer, wherein the organometallic polymer is a ladder silicone-based polymer and the ladder silicone-based polymer is a polymer material having a molecular structure represented by the following formulas (I) or (II):
wherein R is an alkali-soluble group-containing organic group represented by the formula:
in which m is an integer of 1-3; R″ is a hydroxyl group: and g is an integer of 1-3; and n is a positive number of 2 or more for the repeating unit;
wherein R′ is an organic group reoresented by the formula:
in which R′″ is an alkoxy group having 1 to 3 carbon atoms; and m and n are as defined above.
4. A process for producing a semiconductor device, which comnrises a step of applying an organic insulating film material to a substrate, thereby forming a first insulating layer, a step of applying an organometallic polymer material to the first insulating layer, thereby forming a second insulating layer, a step of forming an opening-forming resist pattern on the second insulating layer, a step of forming an opening in the second insulating layer by means of the resist pattern as a mask, a step of forming an opening in the first insulating layer by means of the resist pattern and the second insulating layer as a mask by dry etching, followed by a step of removing the resist, and a step of baking the first insulating layer and the second insulating layer, wherein the organometallic polymer material is a ladder silicone-based polymer material having a molecular structure represented by the following formula (II):
wherein R′ is an organic group of the formula:
in which m is an integer of 1-3; and R′″ is an alkoxy group having 1 to 3 carbon atoms; and n is a positive number of 2 or more for the repeating unit.
5. A process for producing a semiconductor device according to claim 4 , characterized in that the step of forming an opening in the first insulating layer or the second insulating layer is at least one of a step of forming a contact hole and a step of forming a wiring trench.
6. A process for producing a semiconductor device according to claim 4 , characterized in that after the first insulating layer is baked in a temperature range below 350° C., the opening is formed in the first insulating layer.
7. A process for producing a semiconductor device according to claim 4 , characterized in that after the opening is formed in the first insulating layer, the first insulating layer is baked in a temperature range of not less than 350° C.
8. A process for producing a semiconductor device according to claim 4 , characterized in that the opening is formed in the first insulating layer by dry etching, using a plasma gas containing oxygen as the main component.
9. A process for producing a semiconductor device according to claim 4 , characterized in that the second insulating layer has a thickness as large as or smaller than that of the first insulating layer.
10. A process for producing a semiconductor device according to claim 4 , characterized in that the second insulating layer is exposed to a plasma gas containing oxygen as the main component and then subjected to baking treatment.
11. A process for producing a semiconductor device according to claim 4 , characterized in that the opening is formed in the first by dry etching by means of the second insulating layer as a mask, using a plasma gas containing oxygen as the main composed.
12. A process for producing a semiconductor device according to claim 4 , characterized in that the organometallic polymer material has organic functional groups, and the organic functional groups are decomposed and removed by dry etching, using a plasma gas containing oxygen as the main component, and by heat treatment.
13. A process for producing a semiconductor device according to claim 4 , characterized in that the film hardness of the second insulating layer is improved by subjecting the second insulating layer to dry etching, using a plasma gas containing oxygen as the main component, and to heat treatment.
14. A process for producing a semiconductor device, which comprises a step of applying an organic insulating film material to a substrate, thereby forming a first insulating layer, a step of applying an organometallic polymer material to the first insulating layer, thereby forming a second insulating layer, a step of forming an opening-forming resist pattern on the second insulating layer, while forming an opening in the second insulating layer, a step of forming an opening in the first insulating layer by dry etching, while removing the resist, and a step of baking the first insulating layer and the second insulating layer, wherein the organometallic polymer material is a ladder silicone-based polymer material having a molecular structure rerpresented by the following formula (I):
wherein R is an alkali-soluble group-containing organic group of the formula:
in which m is an integer of 1-3; and R′ is a hydroxyl group, and q is an integer of 1-3; and n is a positive number of 2 or more for the repeating unit.