Method for manufacturing semiconductor device
View Patent ↗A method for manufacturing a semiconductor device includes the steps of: forming an etching layer ( 17 ) formed of silicon on a semiconductor substrate ( 10 ); forming a mask layer ( 20 ) with a pattern on the etching layer ( 17 ), which includes an intermediate layer ( 22 ) as a silicon oxide film and a top layer ( 24 ) as a polysilicon; and etching the etching layer ( 17 ) using the mask layer ( 20 ) as a mask, and eliminating the top layer ( 24 ).
1. A method for manufacturing a semiconductor device comprising the steps of:
forming an etching layer formed of silicon on a semiconductor substrate;
forming a mask layer with a pattern on the etching layer, the mask layer including an intermediate layer formed of a silicon oxide film and a top layer formed of silicon, wherein the step of forming the mask layer includes the steps of:
layering the intermediate layer and the top layer on the etching layer;
patterning the intermediate layer and the top layer;
forming a cover layer formed of a silicon oxide film on the patterned intermediate layer and the top layer; and
forming side wall layers on side surfaces of the patterned intermediate layer and the patterned top layer by etching an entire surface of the cover layer to expose the top layer; and
etching the etching layer using the mask layer as a mask, and eliminating the top layer, the etching layer etched to form a plurality of word lines.
2. The method for manufacturing a semiconductor device according to claim 1 , further comprising the steps of:
forming a first layer formed of a silicon oxide film and a second layer formed of a silicon nitride film sequentially between each of the plurality of word lines which have been etched; and
eliminating the intermediate layer on the etching layer.
3. The method for manufacturing a semiconductor device according to claim 2 , further comprising the step of forming a silicide metal layer on an upper portion of the plurality of word lines.
4. The method for manufacturing a semiconductor device according to claim 3 , wherein the step of forming the silicide metal layer includes the step of forming a metal layer on the plurality of word lines, and the step of forming the silicide metal layer from the metal layer and the upper portion of the plurality of word lines through a thermal processing.
5. The method for manufacturing a semiconductor device according to claim 1 , wherein the step of patterning the intermediate layer and the top layer includes the steps of:
forming an antireflective film and a photoresist film on the top layer;
patterning the antireflective film and the photoresist film; and
etching the intermediate layer and the top layer using the photoresist film as the mask.
6. A method for manufacturing a semiconductor device comprising the steps of:
forming an etching layer;
forming a mask layer with a pattern on the etching layer, the mask layer including an intermediate layer and a top layer formed of the same element as that used for forming the etching layer, wherein the step of forming the mask layer includes the steps of:
layering the intermediate layer and the top layer on the etching layer;
patterning the intermediate layer and the top layer;
forming a cover layer formed of a silicon oxide film on the patterned intermediate layer and the top layer; and
forming side wall layers on side surfaces of the patterned intermediate layer and the patterned top layer by etching an entire surface of the cover layer to expose the top layer; and
etching the etching layer using the mask layer as a mask, and eliminating the top layer, the etching layer etched to form a plurality of word lines.
7. The method for manufacturing a semiconductor device according to claim 6 , further comprising the steps of:
forming a first layer and a second layer each formed of the same material as that used for forming the intermediate layer between each of the plurality of word lines which have been etched; and
eliminating the intermediate layer on the etching layer.
8. The method for manufacturing a semiconductor device according to claim 1 , wherein the etching layer is a gate layer.
9. The method for manufacturing a semiconductor device according to claim 6 , wherein the etching layer is a gate layer.
10. The method for manufacturing a semiconductor device according to claim 6 , wherein the step of patterning the intermediate layer and the top layer includes the steps of:
forming an antireflective film and a photoresist film on the top layer;
patterning the antireflective film and the photoresist film; and
etching the intermediate layer and the top layer using the photoresist film as the mask.
11. The method for manufacturing a semiconductor device according to claim 1 , wherein the step of forming the cover layer does not form side wall layers.
12. The method for manufacturing a semiconductor device according to claim 6 , wherein the step of forming the cover layer does not form side wall layers.