IMAGE TRANSFER USING EUV LITHOGRAPHIC STRUCTURE AND DOUBLE PATTERNING PROCESS

1 . A method comprising:

forming an organic planarizing layer over a semiconductor substrate, the organic planarizing layer including a planar upper surface;

forming a hardmask layer on the planar upper surface of the organic planarizing layer;

forming an organic adhesion layer on the hardmask layer;

forming an EUV photosensitive resist layer on the organic adhesion layer;

exposing and developing the EUV photosensitive resist layer with an EUV light source to form an opening therein;

transferring the opening in the EUV photosensitive resist layer to the hardmask layer by reactive ion etching; and

extending the opening into the organic planarizing layer and to the substrate by reactive ion etching.

2 . The method of claim 1 , wherein the semiconductor substrate comprises a layer containing topographical features.

3 . The method of claim 1 , wherein the hardmask layer comprises an uppermost oxide hardmask layer, an intermediate hardmask layer, and a lowermost oxide hardmask layer, wherein the EUV photosensitive resist layer is deposited directly onto the uppermost hardmask layer.

4 . The method of claim 3 , wherein the uppermost and lowermost hardmask layers comprise a low temperature oxide.

5 . The method of claim 3 , wherein the intermediate hardmask layer comprises titanium nitride or an organosilicon.

6 . The method of claim 1 further comprising:

forming an additional EUV photosensitive resist layer on the hardmask layer including the opening; and

exposing and developing the additional EUV photosensitive resist layer with the EUV light source to form an additional opening therein;

wherein forming the additional opening therein is prior to extending the opening into the organic planarizing layer to the substrate.

7 . The method of claim 1 , wherein the opening has a critical dimension of about 14 nanometers and the organic planarizing layer has a thickness of about 60 to 100 nanometers.

8 . The method of claim 1 , wherein the intermediate hardmask layer comprises octylmethylcyclotetrasiloxane.

9 . The method of claim 1 further comprising removing the intermediate hardmask layer by a wet etch process.

10 . A method comprising:

forming an organic planarizing layer over topography formed on a semiconductor substrate, the organic planarizing layer including a planar upper surface;

forming a multilayer hardmask layer on the planar upper surface of the organic planarizing layer comprising an uppermost oxide hardmask layer, an intermediate hardmask layer, and a lowermost oxide hardmask layer;

forming an organic adhesion layer on the uppermost oxide hardmask layer;

forming an EUV photosensitive resist layer on the organic adhesion layer;

exposing and developing the EUV photosensitive resist layer with an EUV light source to form an opening therein;

reactive ion etching to transfer the opening in the EUV sensitive photoresist layer to the uppermost hardmask layer;

forming an additional EUV photosensitive resist layer on the uppermost hardmask layer including the opening;

exposing and developing the EUV photosensitive resist layer with an EUV light source to form an additional opening therein;

reactive ion etching to extend the opening and the additional opening into the intermediate hardmask layer and to the lowermost hardmask layer;

removing the intermediate hardmask layer; and

reactive ion etching to extend the opening and the additional opening into the lowermost oxide hardmask layer and the organic planarizing layer within the same etch chamber.

11 . The method of claim 10 , wherein the opening has a critical dimension of about 14 nanometers and the organic planarizing layer has a thickness of about 60 to 100 nanometers.

12 . The method of claim 10 , wherein the intermediate hardmask layer comprises octylmethylcyclotetrasiloxane.

13 . The method of claim 10 , wherein removing the intermediate hardmask layer comprises a wet etch process.

14 . The method of claim 10 , wherein the uppermost and lowermost hardmask layers comprise a low temperature oxide, and wherein the intermediate hardmask layer comprises titanium nitride or octylmethylcyclotetrasiloxane.

15 . The method of claim 10 , wherein the EUV photosensitive resist is chemically amplified upon exposure to the EUV light source.