Method for fabricating semiconductor device
View Patent ↗A method for fabricating a semiconductor device includes forming a plurality of plugs over a die region and an edge bead removal (EBR) region of a wafer, forming metal lines coupled to the plugs, removing the metal lines in the EBR region, forming an inter-layer dielectric layer over the wafer, and forming a plurality of contact holes that expose the metal lines by selectively etching the inter-layer dielectric layer through a dry etch process using a plasma etch device.
1. A method for fabricating a semiconductor device, comprising:
forming a plurality of plugs over a die region and an edge bead removal (EBR) region of a wafer;
forming metal lines coupled to the plugs in the die region and the EBR region;
removing the metal lines in the EBR region before an inter-layer dielectric layer is formed;
forming the inter-layer dielectric layer over the wafer; and
forming a plurality of contact holes that expose the metal lines in the die region by selectively etching the inter-layer dielectric layer through a dry etch process using a plasma etch device.
2. The method of claim 1 , wherein in removing the metal lines in the EBR region, the metal lines are removed through a wet etch process.
3. The method of claim 2 , wherein the wet etch process is performed by a spin-type wet etch device configured to spray an etch solution to the EBR region of the wafer and rotate the wafer.
4. The method of claim 1 , wherein the metal lines include copper (Cu).
5. The method of claim 4 , wherein in removing the metal lines in the EBR region, the metal lines are removed using a mixed solution of nitric acid (HNO 3 ) and deionized water (H 2 O).
6. The method of claim 5 , wherein the mixed solution is prepared by mixing the deionized water with the nitric acid (HNO 3 ) at a mixing ratio ranging from approximately 1:1 to approximately 1:10.
7. The method of claim 1 , wherein the metal lines include aluminum (Al).
8. The method of claim 7 , wherein in removing the metal lines in the EBR region, the metal lines are removed using a mixed solution of sodium hydroxide (NaOH) and deionized water (H 2 O).
9. The method of claim 8 , wherein the mixed solution is prepared by mixing the deionized water with the sodium hydroxide (NaOH) at a mixing ratio ranging from approximately 1:1 to approximately 1:10.
10. The method of claim 1 , wherein in removing the metal lines in the EBR region, the metal lines are removed using a mixed solution (HCl/HNO 3 /H 2 O) of hydrochloric acid (HCl), nitric acid (HNO 3 ), and deionized water (H 2 O).
11. The method of claim 10 , wherein the percentage of the nitric acid (HNO 3 ) in the mixed solution ranges from approximately 30% to approximately 70% of the entire mixed solution.
12. The method of claim 10 , further including a second inter-layer dielectric layer formed over the plurality of plugs in both the die region and the EBR region, wherein the forming of the metal lines includes depositing a metal layer to fill trenches formed by etching the second inter-layer dielectric layer in both the die region and the EBR region and wherein the removing of the metal lines in the EBR region includes removing the metal layer filled in the trenches of the EBR region.