초록 ▼

The present invention relates to an electroless-plating liquid useful for forming a protective film for selectively protecting surface of exposed interconnects of a semiconductor device which has an embedded interconnect structure formed by an electric conductor, such as copper or silver, embedded i

The present invention relates to an electroless-plating liquid useful for forming a protective film for selectively protecting surface of exposed interconnects of a semiconductor device which has an embedded interconnect structure formed by an electric conductor, such as copper or silver, embedded in fine recesses for interconnects formed in a surface of a semiconductor substrate, and also to a semiconductor device in which surfaces of exposed interconnects are selectively protected with a protective film. The electroless-plating liquid contains cobalt ions, a complexing agent and a reducing agent containing no alkali metal.

대표청구항 ▼

1. A semiconductor device comprising: an interconnect made of copper, copper alloy, silver, or silver alloy, embedded in a trench in a surface of an insulating film, wherein said trench is covered by a barrier layer; and a protective film having a thickness in a range of from 0.1 nm to 500 nm, s

1. A semiconductor device comprising: an interconnect made of copper, copper alloy, silver, or silver alloy, embedded in a trench in a surface of an insulating film, wherein said trench is covered by a barrier layer; and a protective film having a thickness in a range of from 0.1 nm to 500 nm, said protective film selectively covering an exposed surface of said interconnect, and said protective film being formed by an electroless-plating process using an electroless-plating liquid without using palladium, said electroless-plating liquid comprising: (i) cobalt ions; (ii) a complexing agent; and (iii) an alkylamine borane that is free from alkali metal. 2. The semiconductor device according to claim 1, wherein said electroless-plating liquid further comprises at least one of (i) a stabilizer selected from one or more kinds of heavy metal compounds and sulfur compounds, and (ii) a surfactant. 3. The semiconductor device according to claim 1, wherein said electroless-plating liquid has a pH adjusting agent that is free from alkali metal. 4. The semiconductor device according to claim 1, wherein said protective film has a thickness within a range of from 10 nm to 100 nm. 5. A semiconductor device comprising: an interconnect made of copper, copper alloy, silver, or silver alloy, embedded in a trench in a surface of an insulating film, wherein said trench is covered by a barrier layer; and a protective film having a thickness in a range of from 0.1 nm to 500 nm, said protective film selectively covering an exposed surface of said interconnect, and said protective film being formed by an electroless-plating process using an electroless-plating liquid without using palladium, said electroless-plating liquid comprising: (i) cobalt ions; (ii) a complexing agent; (iii) a compound containing a refractory metal; and (iv) an alkylamine borane that is free from alkali metal. 6. The semiconductor device according to claim 5, wherein said refractory compound comprises at least one of tungsten and molybdenum. 7. The semiconductor device according to claim 5, wherein said electroless-plating liquid further comprises at least one of (i) a stabilizer selected from one or more kinds of heavy metal compounds and sulfur compounds, and (ii) a surfactant. 8. The semiconductor device according to claim 5, wherein said electroless-plating liquid has a pH adjusting agent that is free from alkali metal. 9. The semiconductor device according to claim 5, wherein said protective film has a thickness within a range of from 10 nm to 100 nm.