KR20060040858A - Method for forming organic-oxide layers stack and interconnection wiring structure - Google Patents

Abstract

A method of forming a stack of an organic layer and an oxide layer and a method of forming a connection wiring using the same are provided. According to the present invention, a hydrophilic component including a silicon-containing monomer (Si-monomer) and a coating liquid containing a hydrophobic component and a solvent of an organic monomer (organic monomer) having a higher molecular weight than a hydrophilic component are prepared and applied onto a substrate. After forming the coating film, the coating film is heated to form a phase separation between the hydrophobic component and the hydrophilic component, and an organic layer is formed on the lower side by the mutual reaction of the organic monomers, and an oxide layer is simultaneously formed by the mutual reaction of the silicon-containing monomers on the organic layer. . A photoresist pattern is formed on the organic layer and the oxide layer thus formed, and the interlayer insulating layer is etched using the photoresist pattern as an etching mask to form a trench of a dual damascene process.

Hydrophilic, hydrophobic, phase separated, dual damascene, packed bed

Description

Method for forming organic layer and oxide layer and method for forming interconnection wiring using the same {Method for forming organic-oxide layers stack and interconnection wiring structure}

1 is a view schematically illustrating a method of forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

2 is a view schematically illustrating an example of a hydrophilic component of a coating film for forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

3 to 6 schematically illustrate examples of hydrophobic components of a coating film for forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

7 to 14 are cross-sectional views schematically illustrating a connection wiring forming method using a method of forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufacturing technology, and more particularly, to a method of forming a stack of an organic layer and an oxide layer, and a method of forming a connection wiring using the same.

When fabricating a semiconductor device, a layer of an organic layer and an oxide layer may be formed as a preliminary step in the process of patterning a layer. For example, when forming a wiring pattern by a dual damascene process, first forming a via hole and then forming a trench overlapping the upper portion of the via hole, the previous step of forming a trench The process of filling the via via hole with the organic layer and forming an oxide layer on the organic layer may be considered. The dual damascene process uses a photoresist pattern (PR) to etch a lower metal wiring pattern such as aluminum (Al), and pattern a connection wiring and an upper wiring electrically connected to the lower metal wiring pattern. Is being performed.

The stacked structure of the organic layer and the oxide layer introduced in the damascene process is introduced to induce the PR for the trench etching to be formed on the oxide layer to be finely patterned by the photolithography process. Simply, when using a single film PR on the insulating layer on which the via hole is formed, it is very difficult to cope with the reduction of the design rule. In particular, when manufacturing a semiconductor device with a design rule of 90 nm or less, PR is difficult to be formed in the required line width. This may be understood that the flatness of the PR is relatively weak due to the presence of the via hole, thereby reducing the resolution of the photolithography process.

However, when the stacked structure of the organic layer and the oxide layer is introduced into the lower layer of the PR, this process involves the deposition and application of several layers, and the unit processes thereof become very complicated. That is, since deposition and application are performed at different facilities for each layer, the result is a decrease in the put through of semiconductor device fabrication. Therefore, there is a demand for the development of a method for forming the stacked structure of the organic layer and the oxide layer introduced under the PR in a simpler and faster manner.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a method of forming a stacked structure of an organic layer and an oxide layer in a simpler process, and a method of forming a connection wiring using the method.

One aspect of the present invention for achieving the above technical problem, preparing a coating liquid comprising a hydrophilic component comprising a silicon-containing monomer and a hydrophobic component and a solvent of an organic monomer having a greater molecular weight than the hydrophilic component, the Applying a coating liquid onto a substrate to form a coating film, and heating the coating film to cause phase separation between the hydrophobic component and the hydrophilic component and forming an organic layer on the lower side by mutual reaction of the organic monomers, and A method of forming a stack of an organic layer and an oxide layer, including simultaneously forming an oxide layer by mutual reaction of silicon-containing monomers, is provided.

Another aspect of the present invention for achieving the above technical problem is, forming a lower wiring on a semiconductor substrate, forming an interlayer insulating layer covering the lower wiring, the lower through the interlayer insulating layer Forming a via hole aligned with the wiring, preparing a coating solution including a hydrophilic component including a silicon-containing monomer and a hydrophobic component of an organic monomer having a higher molecular weight than the hydrophilic component and a solvent, wherein the interlayer Forming a coating film filling the via hole by applying the coating liquid on an insulating layer, and heating the coating film to cause phase separation between the hydrophobic component and the hydrophilic component and forming an organic layer on the lower side by mutual reaction of the organic monomers. Simultaneously forming an oxide layer on the organic layer by mutual reaction of the silicon-containing monomers Forming a trench connected to the via hole by forming a photoresist pattern on the oxide layer, etching the interlayer insulating layer using the photoresist pattern as an etch mask, and forming the trench and the trench A method of forming a connection wiring including forming a top wiring filling a via hole is provided.

The hydrophilic component may comprise TEOS.

The hydrophobic component is dibenzo-21-crown-7, dibenzo-24-crown-8, dibenzo-30-crown-10 (dibenzo). -30-crown-10) or 2,3,9,10,16,17,23,24-octakis (octyloxy) -29H, 31H-phthalocyanine ((2,3,9,10,16,17, 23,24-Octakis (octyloxy) -29H, 31H-phthalocyanine).

The solvent may comprise water.

The solvent may further include an alcohol solvent such as methanol, ethanol, isopropyl alcohol or butanol.                     

The solvent may further include hydrochloric acid or nitric acid as a catalyst.

The coating solution may be prepared by setting the molar ratio of the hydrophilic component and the hydrophobic component to be equal and setting the molar amount of the water to be 6 to 12 times the molar amount of the hydrophilic component or the hydrophobic component.

According to the present invention, a stack of an organic layer and an oxide layer to be introduced as a lower layer under the photoresist layer may be simultaneously formed, so that the via hole may be filled with the stack of the organic layer and the oxide layer in a dual damascene process. Accordingly, it is possible to implement an increase in productivity in manufacturing a semiconductor device.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention may be modified in many different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. Embodiments of the invention are preferably to be interpreted as being provided to those skilled in the art to more fully describe the invention.

An embodiment of the present invention provides a method of simultaneously forming an organic layer and an oxide layer, and a method of forming a filler filling a via hole in the dual damascene process using the above method.

1 is a view schematically illustrating a method of forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

Referring to FIG. 1, in the exemplary embodiment of the present invention, a stacked structure of an organic layer and an oxide layer is formed by a process including one coating process and a phase separation process. Specifically, a lower layer 200 including an insulating layer such as a silicon oxide layer is formed on the substrate 100, and a hydrophilic component and a hydrophobic organic monomer including a silicon-containing monomer are formed. A suspension in which a hydrophobic component including a monomer is dispersed in a solvent is applied onto the lower layer 200 to form a coating layer 300.

At this time, in the coating film 300, an organic monomer such as a cyclic monomer having a hydrophobic component such as a benzoyl group or a phenyl group, and a hydrophilic component such as TEOS (TetraEthylOrthoSilicate) A siloxane monomer such as) is mixed in the solvent. When the reaction proceeds by applying heat to the coating film 300, the hydrophobic component and the hydrophilic component react separately.

At this time, the hydrophobic component of the relatively high molecular weight organic monomer sinks relatively in the coating film 300, and the silicone-containing monomer of the hydrophilic component having a relatively low molecular weight, for example, the siloxane monomer, floats upward. Will be. That is, phase separation occurs above and below. This phase separation occurs and a reaction between the monomers is caused by the heated energy, thereby forming a stack of two separate layers, that is, an upper oxide layer 330 and a lower organic layer 310 at the same time. In this case, the heating may be performed by a soft bake process.

In this manner, a lamination structure of the organic layer and the oxide layer to be introduced under the photoresist layer may be formed by one coating and a soft baking (or heating) process. Therefore, compared to the case of forming the conventional organic layer and the deposition of the oxide layer in a number of individual steps, it is possible to form a laminated structure of the organic layer and the oxide layer in a relatively fast time, it is possible to implement an increase in the overall productivity.

2 is a view schematically showing an example of a hydrophilic component for a coating film according to an embodiment of the present invention. Referring to FIG. 2, examples of the hydrophilic component for the coating film (300 of FIG. 1) include TEOS, which may be represented by a chemical formula as shown in FIG. 2.

3 to 6 are diagrams schematically showing examples of hydrophobic components for a coating film according to an embodiment of the present invention. Referring to FIGS. 3 to 6, examples of the hydrophobic component for the coating film (300 of FIG. 1) include organic monomers that may be represented by chemical formulas as shown in FIGS. 3 to 6. For example, dibenzo-21-crown-7 of the formula as shown in FIG. 3 or dibenzo-24-crown-8 of the formula as shown in FIG. 4. crown-8) or an organic monomer comprising dibenzo-30-crown-10 of formula as shown in FIG. 5. Or 2,3,9,10,16,17,23,24-octakis (octyloxy) -29H, 31H-phthalocyanine (2,3,9,10,16,17) of the formula as shown in FIG. Organic monomers containing 23,24-Octakis (octyloxy) -29H, 31H-phthalocyanine) can be used.

Referring again to FIG. 1, the coating liquid or suspension for this coating film 300 includes any one or a plurality of silicon-containing monomers as shown in FIG. 2 and organic monomers as shown in FIGS. 3 to 6. Can be prepared. In this case, the solvent may include an alcohol-based solvent such as methanol, ethanol, isopropyl alcohol (IPA), butanol, and the like, and may include water (H ₂ O). In addition, hydrochloric acid and / or nitric acid may be added as a catalyst to such coating liquids.

At this time, the ratio of the hydrophilic component, hydrophobic component, and water for preparing the coating liquid may be such that the molar amount of water is higher than the molar amount of the hydrophilic component and / or the hydrophobic component, and the ratio of the hydrophilic component and the hydrophobic component is equal. It can be done. For example, the molar ratio of TEOS: dibenzo-21-crown-7: water may be approximately 1: 1: 6, and TEOS: dibenzo-24-crown-8 (dibenzo-24). -crown-8): molar ratio of water can be approximately 1: 1: 6, TEOS: dibenzo-30-crown-10: molar ratio of water is approximately 1: 1: 6 TEOS: 2,3,9,10,16,17,23,24-octakis (octyloxy) -29H, 31H-phthalocyanine ((2,3,9,10,16,17,23, The molar ratio of 24-Octakis (octyloxy) -29H, 31H-phthalocyanine): water may be approximately 1: 1: 12.

In the method of simultaneously forming the organic layer and the oxide layer according to the embodiment of the present invention, before forming the photoresist layer, the flatness of the lower film quality is increased or the grooves or holes are formed in the lower film quality. When it is necessary to fill the filled layer, it can be used in the process of forming the lower layer of the photoresist layer. This pattern formation process may be described by taking a dual damascene process for forming a connection line as an example.

7 to 14 are cross-sectional views schematically illustrating a connection wiring forming method using a method of forming a stack of an organic layer and an oxide layer according to an embodiment of the present invention.

Referring to FIG. 7, a lower wiring 1150 as a metal wiring such as aluminum (Al), copper (Cu), and / or tungsten (W) is disposed on a semiconductor substrate 1100 through an insulating layer (not shown). The interlayer insulating layer 1200 may be formed on the lower wiring 1150. In this case, the lower wiring 1150 may be patterned by a damascene process or a selective etching process using photolithography. The periphery of the lower wiring 1150 may be insulated by the lower insulating layer 1153, and an etch stop layer 1155 may be introduced on the upper surface of the lower wiring 1150. In this case, the etching termination layer may include silicon nitride (SiN), silicon carbide (SiC), silicon carbide nitride (SiCN) or / and silicon carbide oxide (SiCO).

The interlayer insulating layer 1200 formed on the lower interconnection 1150 may protect the first interlayer insulating layer 1210 and the first interlayer insulating layer 1210 including a low dielectric constant (low-k) dielectric material. A second interlayer insulating layer 1230 may be formed. Low dielectric constant dielectric materials include SOG (Silicon On Glass) materials, HSQ, MSQ, Siloxane-based materials, organic polymer materials and the like. Of course, the first interlayer insulating layer 1210 may be a layer formed by CVD (Chemical Vapor Deposition) such as silicon oxide or silicon oxide carbide. The second interlayer insulating layer 1230 may be a TEOS layer.

Referring to FIG. 8, a via hole 1205 penetrating the interlayer insulating layer 1200 is formed. In order to form the via holes 1205, a first etching mask 1250 may be introduced on the interlayer insulating layer 1200. The first etching mask 1250 may include a photoresist pattern or / and a hard mask. The via hole 1250 is formed to be aligned with the lower wiring 1150 according to the dual damascene process. Thereafter, the first etching mask 1250 is removed.

Referring to FIG. 9, a coating film 1300 filling the via hole 1205 is formed on the interlayer insulating layer 1200. The coating film 1300 is formed by applying a coating liquid containing a hydrophilic component and a hydrophobic component as described with reference to FIG. 1.

Referring to FIG. 10, the coating film 1300 is phase-separated to form a stacked structure of the lower organic layer 1310 and the upper oxide layer 1330. As described with reference to FIG. 1, the coating film 1300 is soft baked, ie, heated to induce phase separation and induces phase-separated monomodals to react, thereby forming a structure in which the organic layer 1310 and the oxide layer 1330 are stacked. do. In this case, the stacking of the organic layer 1310 and the oxide layer 1330 may be understood as a filling layer filling the via hole 1205.

Referring to FIG. 11, after the photoresist layer 1350 is coated on the upper oxide layer 1330, the photoresist pattern 1350 is formed by soft baking and exposing and developing the photolithography process. It may be understood that the photoresist pattern 1350 is introduced as a second etching mask for the trench of the dual damascene process.

Referring to FIG. 12, the lower interlayer insulating layer 1200 is etched using the photoresist pattern 1350 as a second etching mask to form a trench 1201 connected to the via hole 1205. In this case, the organic layer 1310 and the oxide layer 1330 under the photoresist pattern 1350 may serve as a kind of hard mask. That is, when the oxide layer 1330 also extends in the lower organic layer 1310 or in some cases, the via hole 1205, the extension portion of the oxide layer 1330 may be etched by the via hole 1205 to form the trench 1201. Exposure to the process acts as a protective or packed layer that prevents the profile from being damaged.

Referring to FIG. 13, the photoresist pattern 1350, the oxide layer 1330, and the organic layer 1310 are selectively removed. At this time, an ashing process may be used to effectively and selectively remove these layers.

Referring to FIG. 14, the conductive layer filling the trench 1201 and the via hole 1205 connected thereto is formed and planarized to form an upper wiring 1170 having a connection portion. In this case, the upper wiring 1170 may include Al, Cu, and / or W. In addition, the planarization process may be performed by chemical mechanical polishing (CMP). After forming the connection wiring structure as described above, an upper interlayer insulating layer (not shown) covering the upper wiring may be further formed. The upper interlayer insulating layer may be formed of SOG, SiOC, SiC, SiN, SiCN or a composite layer structure having a combination thereof.

According to the present invention as described above, after the application of the coating film, if the reaction proceeds by applying heat to the hydrophilic component and the hydrophobic component mixed in the film, the hydrophilic component and the hydrophobic component will react separately, and the hydrophobic with high molecular weight The component sinks to the bottom of the film, so that phase separation occurs, and two separate layers, an organic layer, which is a bottom layer, and an oxide layer positioned on the upper side thereof may be simultaneously formed. By using this method, since only two processes of applying a single film and subsequently applying PR can replace the process of going through the three existing films separately, the productivity of the process of manufacturing a semiconductor device can be greatly improved.

As mentioned above, although this invention was demonstrated in detail through the specific Example, this invention is not limited to this, It is clear that the deformation | transformation and improvement are possible by the person of ordinary skill in the art within the technical idea of this invention.

Claims (8)

Preparing a coating solution including a hydrophilic component including a silicon-containing monomer and a hydrophobic component and a solvent of an organic monomer having a higher molecular weight than the hydrophilic component; Applying the coating liquid onto a substrate to form a coating film; And Heating the coating film to form a phase separation between the hydrophobic component and the hydrophilic component and forming an organic layer on the lower side by mutual reaction of the organic monomers, and simultaneously forming an oxide layer on the organic layer by mutual reaction of the silicon-containing monomers. Method for forming a stack of the organic layer and the oxide layer comprising a. The method of claim 1, Wherein said hydrophilic component comprises TEOS. The method of claim 1, The hydrophobic component is dibenzo-21-crown-7, dibenzo-24-crown-8, dibenzo-30-crown-10 (dibenzo). -30-crown-10) or 2,3,9,10,16,17,23,24-octakis (octyloxy) -29H, 31H-phthalocyanine ((2,3,9,10,16,17, 23,24-Octakis (octyloxy) -29H, 31H-phthalocyanine). A method for forming a stack of an organic layer and an oxide layer. The method of claim 1, Wherein said solvent comprises water. The method of claim 4, wherein The solvent is a method of forming a stack of the organic layer and the oxide layer, characterized in that further comprises any one selected from the alcohol-based group including methanol, ethanol, isopropyl alcohol and butanol. The method of claim 4, wherein The solvent is a method of forming a stack of an organic layer and an oxide layer, further comprising hydrochloric acid or nitric acid as a catalyst. The method of claim 4, wherein The coating liquid equally sets the molar ratio of the hydrophilic component and the hydrophobic component And a molar amount of the water is set to be 6 to 12 times the molar amount of the hydrophilic component or the hydrophobic component to form a stack of the organic layer and the oxide layer. Forming a lower wiring on the semiconductor substrate; Forming an interlayer insulating layer covering the lower wiring; Forming a via hole aligned with the lower interconnection through the interlayer insulating layer; Preparing a coating solution including a hydrophilic component including a silicon-containing monomer and a hydrophobic component and a solvent of an organic monomer having a higher molecular weight than the hydrophilic component; Forming a coating film filling the via hole by applying the coating liquid on the interlayer insulating layer; Heating the coating film to form a phase separation between the hydrophobic component and the hydrophilic component and forming an organic layer on the lower side by mutual reaction of the organic monomers, and simultaneously forming an oxide layer on the organic layer by mutual reaction of the silicon-containing monomers. ; Forming a photoresist pattern on the oxide layer; Etching the interlayer insulating layer using the photoresist pattern as an etch mask to form a trench connected to the via hole; And And forming an upper interconnection to fill the trench and the via hole.

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