Methods for multiple patterning of substrates

Abstract

This invention relates to a method for multi-patterning a substrate. A method for providing etch selectivity in a substrate processing is disclosed. More specifically, a plasma treatment of multiple exposed structures comprising different materials is provided. The plasma treatment preferentially enhances the etch selectivity among at least two of the exposed structures. In one embodiment, multiple exposed structures are used as part of a multi-patterning substrate process. In one embodiment, the exposed structures may include an organic planarization layer and a spin-coated metal layer. The plasma treatment may include a plasma formed using nitrogen and hydrogen and the emission of vacuum ultraviolet (VUV) wavelength radiation from such plasma.

Description

Technical Field

[0001] This disclosure relates to the processing of substrates, such as semiconductor substrates. Specifically, a novel method for improving the multiple patterning processing of substrates is provided. Background Technology

[0002] As the geometry of substrate processing continues to shrink, the technical challenges of forming structures on substrates increase. These challenges are particularly evident in the fields of photolithography and etching processes. One technique for achieving suitable photolithography for increasingly smaller critical dimensions involves multiple patterning techniques to provide spacing division. Such multiple patterning techniques include, for example, self-aligned dual patterning, self-aligned triple patterning, and self-aligned quadruple patterning. These multiple patterning techniques can involve utilizing sidewall spacers, filler layers, and selective etching to define structures at spacings smaller than the original photolithographic pitch.

[0003] For example, in self-aligned dual patterning techniques, sidewall spacers are used to increase the structure density on the substrate surface. A mandrel structure can be formed on the substrate using known photolithography techniques. Sidewall spacers can then be formed near the mandrel. Removal of the original patterned mandrel leaves two sidewall spacers, thus forming two structures for each mandrel. Similarly, self-aligned triple and quadruple patterning techniques are known in which additional sidewall spacers of different materials can be formed near the first sidewall spacer. Multiple patterning techniques typically involve multiple masking steps. The first step can be called mandrel masking, and the subsequent masking steps can be called block masking. At various points in the multiple patterning process flow, it is known that various exposed structures (mandrel, first sidewall spacer, second sidewall spacer, planarization layer, spin coating, etc.) can be selectively etched relative to other exposed structures. The ability to achieve high etch selectivity in multiple materials during multiple patterning is an important aspect of realizing multiple patterning processes.

[0004] Therefore, for example, such as Figure 1AAs shown, an exemplary structure 100 that may be encountered during a multiple patterning process in a substrate processing manufacturing flow is illustrated. As shown, a substrate 105 is provided, and a hard mask layer 110 is provided. A plurality of multiple patterning process structures are formed over the hard mask layer 110. For example, sidewall spacers 115, an organic planarization layer 120, and a spin-coated metal layer 125 are provided. As those skilled in the art will recognize, during a multiple patterning process, it may be desirable to selectively etch one of the multiple patterned structures relative to one or more of the other multiple patterned structures. Thus, for example, a multiple patterning process may be a process in which it is desirable to etch the organic planarization layer 120 selectively relative to the sidewall spacers 115 and the spin-coated metal layer 125. However, it has been found that the etching of the organic planarization layer 120 is generally low-selective relative to the etching of the spin-coated metal layer 125. Specifically, while the presence of metal in the spin-coated metal material can increase the selectivity between the organic planarization layer and the spin-coated metal layer, the presence of organic matter in the spin-coated metal material can decrease the selectivity. Specifically, the amount of organic material typically required to provide good filling and planarization properties for the rotating metal layer 125 will result in unsatisfactory etch selectivity. For example, Figure 1B An exemplary result can be seen after etching the organic planarization layer 120. (See example.) Figure 1B As shown, the organic planarization layer 120 has been completely etched; however, as shown in the remaining portion 125A of the spin-coated metal layer 125, a large portion of the spin-coated metal layer has also been etched. Therefore, as... Figure 1C As shown, the hard mask layer 110 is removed after etching in the opening region 130 (where the organic planarization layer 120 is removed). However, significant thinning of the spin-coated metal layer 125 can cause the hard mask layer 110 to also be etched, as shown in the thinned hard mask region 140. The hard mask may be thinned so much that it is completely removed during the etching of the hard mask or during subsequent etching of the layers beneath it, leading to defects such as pattern failure and / or punch-through in multi-patterning processes.

[0005] The aim is to provide substrate processing techniques that improve etch selectivity among exposed structures (e.g., exposed structures of multiple patterning processes). Summary of the Invention

[0006] This document describes an innovative method for providing etch selectivity in substrate processing. More specifically, plasma processing of multiple exposed structures comprising multiple materials is provided. The plasma processing preferentially enhances the etch selectivity between at least two exposed structures. In one embodiment, multiple exposed structures are used as part of a multi-patterned substrate process. In one embodiment, the exposed structures may include an organic planarization layer and a spin-coated metal layer. The plasma processing may include a plasma formed using nitrogen and hydrogen and the emission of vacuum ultraviolet (VUV) wavelength radiation from such plasma.

[0007] In one embodiment, a method for processing a substrate is provided. The method may include: providing a substrate, providing a spin-coated metal layer, and providing a second layer, wherein both the surface of the spin-coated metal layer and the surface of the second layer are exposed. The method may further include: treating the surface of the spin-coated metal layer and the surface of the second layer with a first plasma process, the treatment increasing the etch selectivity between the spin-coated metal layer and the second layer. The method may further include: plasma etching the second layer with a second plasma process, while simultaneously exposing the spin-coated metal layer to the second plasma process, the increased etch selectivity between the spin-coated metal layer and the second layer reducing the amount of the spin-coated metal layer removed during the second plasma process.

[0008] In another embodiment, a method for multiple patterning of a substrate is provided. The method may include: providing the substrate, providing a spin-coated metal layer, and providing an organic planarization layer. The method may further include treating the spin-coated metal layer with a first plasma process. The method may further include simultaneously exposing both the spin-coated metal layer and the organic planarization layer to a second plasma process, the second plasma process etching the organic planarization layer. Treating the spin-coated metal layer with the first plasma process improves the etch selectivity between the spin-coated metal layer and the organic planarization layer during the second plasma process, such that less of the spin-coated metal layer is removed during the second plasma process due to the first plasma process.

[0009] In another embodiment, a method for multiple patterning of a substrate is provided. The method includes providing the substrate having a patterned structure, the patterned structure including an oxide layer, an organic planarization layer, a spin-coated metal layer, and a hard mask layer. The method may further include exposing at least the oxide layer, the organic planarization layer, and the spin-coated metal layer of the patterned structure to a gas comprising nitrogen and hydrogen and to vacuum ultraviolet radiation using a first plasma process, the first plasma process being used to improve etch selectivity between the organic planarization layer and the spin-coated metal layer. The method may further include performing a plasma etching process to etch the organic planarization layer, wherein the organic planarization layer, the oxide layer, and the spin-coated metal layer are all exposed to the plasma etching process, the plasma etching process being used to selectively etch the organic planarization layer relative to the oxide layer and the spin-coated metal layer, such that pattern failure and / or punch-through do not occur. Attached Figure Description

[0010] A more complete understanding of the invention and its advantages can be obtained by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numerals indicate like features. However, it should be noted that the drawings illustrate only exemplary embodiments of the disclosed concepts and should therefore not be construed as limiting the scope, as the disclosed concepts can allow for other equally effective embodiments.

[0011] Figures 1A to 1C Exemplary prior art structures and process flows used during multi-patterned substrate processes are shown.

[0012] Figures 2A to 2D An exemplary process flow using the etching selectivity technique described herein is shown.

[0013] Figures 3 to 5 Exemplary steps of an exemplary method using the techniques described herein are shown. Detailed Implementation

[0014] Figures 2A to 2D An exemplary process flow using the etching techniques disclosed herein is provided. Techniques relating to partial multiple patterning processes are described, but it will be appreciated that these techniques are not limited to multiple patterning process flows. Figure 2A As shown, an exemplary structure 100 may be encountered during a multiple patterning process in a substrate processing manufacturing flow. This exemplary structure is related to... Figure 1A The structure shown is consistent. For example... Figure 2AAs shown, a substrate 105 is provided. The substrate 105 can be any substrate for which patterning features are required. For example, in one embodiment, the substrate 105 can be a semiconductor substrate having one or more semiconductor processing layers formed thereon. In one embodiment, the substrate 105 can be a substrate that has undergone multiple semiconductor processing steps, which produce a variety of different structures and layers, all of which are known in the field of substrate processing. A hard mask layer 110 is also provided. The hard mask layer 110 can be a silicon layer, a silicon nitride layer, or a combination thereof. However, it will be appreciated that the hard mask layer 110 can be formed from any other material among a variety of different materials known in the art to be suitable for use as a hard mask layer in a patterning process.

[0015] Multiple multi-patterned process structures are formed over the hard mask layer 110. For example, sidewall spacers 115, an organic planarization layer 120, and a spin-coated metal layer 125 are provided. It will be appreciated again that the specific multi-patterned structures shown are merely exemplary, and many other multi-patterned structures and materials can be used while still achieving the advantages of the techniques described herein. Furthermore, upon benefiting from this disclosure, it will be appreciated that the techniques described herein are not limited to the multi-patterned process steps of a substrate process flow. Rather, the described layer treatment and etching techniques can be applied to other process steps, all of which are recognized by those skilled in the art upon benefiting from this disclosure.

[0016] In one embodiment, the sidewall spacer 115 may be an oxide sidewall spacer, such as silicon oxide. Other sidewall spacers may be used, such as, but not limited to, silicon nitride, metal oxides, etc. In one embodiment, the organic planarization layer 120 may be any of a variety of different layers comprising an organic material, for example, it may be an organic material using materials such as cyclohexanone, propylene glycol methyl ether (PGME), and propylene glycol monomethyl ether acetate (PGMEA). Other organic planarization materials may be used, such as, but not limited to, chemical vapor deposition carbon, amorphous carbon, etc. The organic planarization layer may be formed in various ways, including but not limited to spin coating, plasma technology, etc. In one embodiment, the spin-coated metal layer 125 may be a titanium oxide contained in a solvent (e.g., cyclohexanone, PGME, or PGMEA). Other spin-coated metals may be used, such as, but not limited to, zirconium oxide (ZrO2). x ), tin oxide (SnO x ), aluminum oxide (AlO) x )wait.

[0017] Then it can be made Figure 2AThe exemplary structure 100 undergoes a plasma process to modify the exposed surface of the spin-coated metal layer 125. Specifically, the plasma process can modify the surface of the spin-coated metal layer 125, thereby increasing the etch selectivity between the organic planarization layer 120 and the spin-coated metal layer 125. In this way, for example... Figure 1B Undesirable etching of the spin-coated metal layer 125 as shown in the prior art is minimized. Therefore, as... Figure 2B As shown, an upper layer 125C of the spin-coated metal layer 125 can be generated after the spin-coated metal layer 125 is exposed to a plasma process. Then, as... Figure 2C As shown, etching of the organic planarization layer 120 can occur. The improved etch selectivity between the organic planarization layer 120 and the upper layer 125C of the spin-coated metal layer 125 provides... Figure 2C The results shown demonstrate that the spin-coated metal layer is essentially unetched. The process can then proceed as follows: Figure 2D The hard mask etching steps are shown. (As shown) Figure 2D As shown, the hard mask layer 110 is removed in the opening region 130 (where the organic planarization layer 120 is removed). However, compared to the prior art, the hard mask layer 110 is still protected in the region corresponding to the spin-coated metal layer 125. In this way, the pattern of the organic planarization layer 120 is transferred to the hard mask layer 110.

[0018] As described, plasma treatment of multiple exposed structures comprising multiple materials is provided. Plasma treatment preferentially enhances the etch selectivity between at least two exposed structures. In one embodiment, the multiple exposed structures are structures used as part of a partial multiple patterning substrate process. In one embodiment, the exposed structures may include an organic planarization layer and a spin-coated metal layer. It should be appreciated that the techniques described herein can be advantageously used in various substrate processing steps. Exemplary process steps include multiple patterning process steps. However, as those skilled in the art will recognize, this technique can be used in other process steps.

[0019] A variety of different plasma techniques can be used to tune the selectivity of one of the exposed multiple patterned structures relative to others. One such technique is described herein; however, it will be appreciated that other techniques can be used. For example, a plasma process that exposes the upper surface of the spin-coated metal layer 125 to a plasma containing nitrogen and hydrogen can be used. Furthermore, vacuum ultraviolet wavelength radiation emitted from such a plasma also provides a beneficial modification to the spin-coated metal layer 125, enabling the formation of an upper layer 125C of the spin-coated metal layer 125 with increased etch resistance of the organic planarization layer. In another embodiment, the upper surface of the spin-coated metal layer 125 can be exposed to a plasma process containing a plasma containing sulfur-containing gas and oxygen. For example, the gas can be sulfur dioxide and oxygen. In yet another embodiment, the spin-coated metal layer 125 can be modified using a two-step plasma process: a first step comprising a plasma formed with nitrogen and hydrogen, and a second step comprising a plasma formed with sulfur dioxide and oxygen. For example, in such a process, a spin-coated metal material (e.g., titanium oxide) can be densified by nitrogen and hydrogen plasma and vacuum ultraviolet (VUV) wavelength radiation emitted by such plasma, thereby forming an etch-resistant upper layer. Furthermore, carbonaceous material in the spin-coated metal can be removed by nitrogen and hydrogen plasma, leaving a more metal-rich (e.g., titanium) surface layer. Additionally, a plasma step formed by sulfur dioxide and oxygen can provide further enhancements in selectivity. For example, the selectivity of the spin-coated metal layer 125 can be tuned by depositing sulfur oxides on the spin-coated metal layer using sulfur dioxide and oxygen. Other mechanisms can also provide selectivity that limits the enhancement of etching of the spin-coated metal layer 125, as the techniques described herein are not limited to specific mechanisms.

[0020] This document describes an exemplary plasma process in more detail; however, other plasma processes can be used, and specific variables (power, pressure, gas, etc.) can be changed while still obtaining the benefits of the techniques described herein. One exemplary plasma process that can be used has a pressure range of 10 mT to 100 mT, a high-frequency power range of 100 W to 800 W, and a low-frequency power range of 50 W to 600 W. The first step of the plasma process can involve a flow of nitrogen and hydrogen, with the nitrogen flow rate generally higher than the hydrogen flow rate. For example, 300 standard cubic centimeters per minute (SCCM) of nitrogen and 150 SCCM of hydrogen can be used. The second step of the plasma process can involve a flow of sulfur dioxide and oxygen, with the sulfur dioxide flow rate generally higher than the oxygen flow rate. For example, 80 SCCM of sulfur dioxide and 40 SCCM of oxygen can be used.

[0021] By utilizing an additional plasma surface treatment of the spin-coated metal layer 125, an upper layer 125C of the spin-coated metal layer 125 can be formed, which provides etch resistance relative to the etching of the organic planarization layer. In one embodiment, without using the additional plasma surface treatment, the etch selectivity between the organic planarization layer and the spin-coated metal layer can be approximately 1:1. An exemplary etching process can be plasma etching with a pressure range of 10 mT to 100 mT, a high-frequency power range of 100 W to 800 W, and a low-frequency power range of 50 W to 600 W. Various different gas combinations and flow rates can be used. For example, the process gas can be O2 only (100 SCCM), CO2 only (100 SCCM), CO2 / Ar (100 / 300 SCCM), O2 / Ar (100 / 300 SCCM), O2 / He (100 / 300 SCCM), CO2 / He (100 / 300 SCCM), or H2 / Ar (200 / 200 SCCM). The etch selectivity achievable by using additional plasma surface treatment can be at least about 2:1, more preferably at least 4:1. Therefore, in one embodiment, both the organic planarization layer and the spin-coated metal layer can be about 59 nm to 100 nm thick. For example, by using additional plasma surface treatment, a 50 nm organic planarization layer can be completely removed, leaving a spin-coated metal layer of at least about 25 nm, more preferably at least 40 nm. In this way, the hard mask layer in the region of the spin-coated metal layer can be protected during the etching of the hard mask layer.

[0022] Therefore, a technique is described that includes treating the surface of a spin-coated metal layer with a first plasma process. The first plasma process increases the etch selectivity between the spin-coated metal layer and the organic planarization layer during plasma etching of the organic planarization layer. For example, the first plasma process densifies the upper region of the spin-coated metal layer. In this way, the increased etch selectivity reduces the amount of spin-coated metal layer removed when the spin-coated metal layer is exposed to plasma etching of the organic planarization layer. It will be appreciated that the technique described herein is particularly useful during multi-patterned substrate processes, as such processes involve simultaneously exposing various layers to a plasma etching process, relying on the etch selectivity of each layer to provide the final desired pattern. In one embodiment, treating the spin-coated metal layer includes exposing the spin-coated metal layer to nitrogen and hydrogen gases, as well as vacuum ultraviolet radiation, during a plasma process. The increased selectivity of the spin-coated metal layer allows the organic planarization layer and the hard mask layer to be etched in such a way that the hard mask is removed only in the region of the organic planarization layer without causing pattern failure or punch-through in other regions. Thus, a hard mask pattern can be formed in the hard mask layer. In one implementation, the spacing of the hard mask patterns in the hard mask layer can be equal to or less than 10 nm. In this way, very small geometric spacing can be produced by relying on self-aligned multi-patterned process structures and the ability to selectively etch these structures to each other.

[0023] Although this document generally describes a first plasma process for treating the surface of spin-coated metal and a second plasma process for etching an organic planarization layer, it will be appreciated that a single plasma process can be used for both the first and second plasma processes. In this case, plasma etching and the first plasma process (surface treatment plasma process) are performed simultaneously. Thus, the plasma etching of the organic planarization layer is performed through the first plasma process (surface treatment process). In this way, a one-step plasma process can be used. For example, a plasma formed with nitrogen and hydrogen can simultaneously treat the surface of spin-coated metal and etch the organic planarization layer. Similarly, a plasma formed with sulfur dioxide and oxygen can both treat the surface of spin-coated metal and etch the organic planarization layer. Therefore, the first and second plasma processes can be combined into a single simultaneous process, or the first and second plasma processes can be different processes performed sequentially.

[0024] Figures 3 to 5Exemplary process flows using the techniques described herein are provided. It will be appreciated that these process flows are merely exemplary, and the techniques described herein can be used in other ways. Furthermore, it will be appreciated that the advantageous benefits of the techniques disclosed herein can still be utilized while adding additional steps to the exemplary process flows. Additionally, those skilled in the art will recognize that the individual steps of the process flow can be performed together, in combination, or in a different order; therefore, the individual steps of the process flow are not limited to the separate, independent process steps shown in the figures.

[0025] Figure 3 A method for processing a substrate is illustrated. The process flow of this method may include step 305: providing a substrate, providing a spin-coated metal layer, and providing a second layer, wherein both the surface of the spin-coated metal layer and the surface of the second layer are exposed. The process flow may then proceed to step 310: treating the surface of the spin-coated metal layer and the surface of the second layer with a first plasma process, which increases the etch selectivity between the spin-coated metal layer and the second layer. The process flow may then proceed to step 315: plasma etching the second layer with a second plasma process while simultaneously exposing the spin-coated metal layer to the second plasma process, the increased etch selectivity between the spin-coated metal layer and the second layer resulting in a reduced amount of spin-coated metal layer removed during the second plasma process.

[0026] Figure 4 A method for multiple patterning of a substrate is illustrated. The process flow of this method may include step 405: providing a substrate, providing a spin-coated metal layer, and providing an organic planarization layer. The process flow may then proceed to step 410: treating the spin-coated metal layer with a first plasma process. The process flow may then proceed to step 415: simultaneously exposing both the spin-coated metal layer and the organic planarization layer to a second plasma process, wherein the second plasma process etches the organic planarization layer, wherein treating the spin-coated metal layer with the first plasma process improves the etch selectivity between the spin-coated metal layer and the organic planarization layer during the second plasma process, resulting in a reduction in the amount of spin-coated metal layer removed during the second plasma process due to the first plasma process.

[0027] Figure 5A method for multiple patterning of a substrate is illustrated. The process flow of this method may include step 505: providing a substrate with a patterned structure comprising an oxide layer, an organic planarization layer, a spin-coated metal layer, and a hard mask layer. The process flow may then proceed to step 510: exposing the oxide layer, organic planarization layer, and spin-coated metal layer of the patterned structure to at least a gas containing nitrogen and hydrogen and to vacuum ultraviolet radiation using a first plasma process, thereby improving the etch selectivity between the organic planarization layer and the spin-coated metal layer. The process flow may then proceed to step 515: performing a plasma etching process to etch the organic planarization layer, wherein the organic planarization layer, oxide layer, and spin-coated metal layer are all exposed to the first plasma etching process, the plasma etching process being used to selectively etch the organic planarization layer relative to the oxide layer and the spin-coated metal layer, such that pattern failure and / or punch-through do not occur.

[0028] although Figures 3 to 5 The exemplary process flow describes a first plasma process for treating the surface of a spin-coated metal layer and a second plasma process for etching an organic planarization layer, but it will be appreciated that the first and second plasma processes can be a single combined plasma process as described above. In this case, a single plasma process can simultaneously treat the surface of the spin-coated metal layer and etch the organic planarization layer.

[0029] Although the ideas disclosed herein have been described in exemplary embodiments of the multi-patterning process, it should be recognized that this technique can be used in other stages of substrate preparation. Therefore, the additional plasma surface treatments described herein can be used at any stage where it is desired to improve the etch selectivity of the spin-coated metal layer. In this way, those skilled in the art will recognize (after benefiting from the disclosure provided herein) that the described techniques can be used in a variety of ways during substrate preparation.

[0030] It should be recognized that the layers and materials containing the layers described herein are merely exemplary. However, other materials can be used, and the ideas described herein can be implemented even without using such layers. Furthermore, it should be recognized that, as those skilled in the art will understand, the various process layers and structures shown can be used in conjunction with other intermediate process layers and coatings. Thus, for example, more or less material can be used between the multi-patterned structure and the hard mask layer 110, and other layers or coatings can be used between the hard mask layer 110 and the substrate 105, etc. Therefore, it should be recognized that using plasma surface treatment to improve the etch selectivity of the multi-patterned structure can be achieved in a variety of ways.

[0031] In view of this description, further modifications and alternative embodiments of the invention will be apparent to those skilled in the art. Therefore, this description is to be construed as illustrative only and is intended to teach those skilled in the art how to practice the invention. It should be understood that the forms and methods of the invention shown and described herein should be considered as currently preferred embodiments. Equivalent techniques may be used in place of those shown and described herein, and certain features of the invention may be used independently of the use of other features, all of which will be apparent to those skilled in the art after benefiting from the description of the invention.

Claims

1. A method for processing a substrate, the method comprising: providing the substrate; providing a spin-on metal layer; providing a second layer, wherein both the spin-on metal layer surface and the second layer surface are exposed; surface modifying the spin-on metal layer surface and the second layer surface with a first plasma process to at least densify one surface of the spin-on metal layer, the surface modification increasing an etch selectivity between the spin-on metal layer and the second layer; and plasma etching the second layer while the spin-on metal layer is also exposed, the increased etch selectivity between the spin-on metal layer and the second layer reducing an amount of the spin-on metal layer removed during the plasma etching of the second layer.

2. The method of claim 1, wherein the first plasma process comprises using nitrogen and hydrogen.

3. The method of claim 2, wherein the first plasma process comprises emitting vacuum ultraviolet wavelength radiation.

4. The method of claim 3, wherein the second layer comprises an organic material.

5. The method of claim 4, wherein a pattern of the second layer is transferred to a hard mask layer underneath the second layer.

6. The method of claim 5, further comprising a sidewall spacer, a surface of the sidewall spacer being exposed to the first plasma process.

7. The method of claim 3, wherein the first plasma process comprises using a sulfur containing gas.

8. The method of claim 1, wherein the first plasma process comprises using a sulfur containing gas.

9. The method of claim 1, wherein plasma etching the second layer is performed using a second plasma process, the first plasma process and the second plasma process being different processes.

10. The method of claim 1, wherein plasma etching the second layer is performed by the first plasma process.

11. A method for multiple patterning processing of a substrate, the method comprising: providing the substrate; providing a spin-on metal layer; providing an organic planarization layer; surface modifying the spin-on metal layer with a first plasma process to at least densify one surface of the spin-on metal layer; and exposing both the spin-on metal layer and the organic planarization layer to a plasma etch simultaneously, the plasma etch etching the organic planarization layer, wherein surface modifying the spin-on metal layer with the first plasma process improves an etch selectivity between the spin-on metal layer and the organic planarization layer during a second plasma process, such that less of the spin-on metal layer is removed during the second plasma process due to the first plasma process.

12. The method of claim 11, wherein the plasma etch and the first plasma process are performed simultaneously.

13. The method of claim 11, wherein the plasma etch and the first plasma process are different processes. ​ 14. The method of claim 13, wherein the first plasma process comprises using nitrogen and hydrogen.

15. The method of claim 14, wherein the first plasma process comprises emitting vacuum ultraviolet wavelength radiation.

16. The method of claim 14, wherein the first plasma process comprises using a sulfur containing gas.

17. The method of claim 16, wherein the first plasma process is a two-step plasma process, the first step comprising using nitrogen and hydrogen, and the second step comprising using a sulfur containing gas.

18. The method of claim 17, wherein the second step comprises using sulfur dioxide gas and oxygen.

19. The method of claim 13, further comprising providing a sidewall spacer, wherein the sidewall spacer, the spin-on metal layer, and the organic planarization layer are all simultaneously exposed to the plasma etch.

20. The method of claim 19, wherein a pattern of the organic planarization layer is transferred to a hardmask layer, the hardmask layer underlying the sidewall spacer, the spin-on metal layer, and the organic planarization layer.

21. A method for multiple patterning processing of a substrate, the method comprising: providing the substrate having a patterned structure, the patterned structure comprising an oxide layer, an organic planarization layer, a spin-on metal layer, and a hardmask layer; exposing at least the oxide layer, the organic planarization layer, and the spin-on metal layer of the patterned structure to a gas comprising nitrogen and hydrogen and to vacuum ultraviolet radiation using a first plasma surface modification process, the first plasma surface modification process at least densifying a surface of the spin-on metal layer and serving to increase etch selectivity between the organic planarization layer and the spin-on metal layer; and performing a plasma etch process to etch the organic planarization layer, wherein the organic planarization layer, the oxide layer, and the spin-on metal layer are all exposed to the plasma etch process, the plasma etch process serving to selectively etch the organic planarization layer relative to the oxide layer and the spin-on metal layer such that no pattern failure and / or breakthrough occurs.

22. The method of claim 21, further comprising forming a hardmask pattern in the hardmask layer, the hardmask pattern having a pitch equal to or less than 10 nm.

23. The method of claim 21, wherein the first plasma surface modification process comprises using a sulfur containing gas.

24. The method of claim 23, wherein the first plasma surface modification process is a two-step plasma process, the first step comprising using a gas comprising nitrogen and hydrogen, and the second step comprising using a sulfur containing gas.

25. The method of claim 24, wherein the second step comprises using sulfur dioxide gas and oxygen.

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