JPH0936110A - Manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device manufacturing method with which a highly reliable semiconductor device can be manufactured at low cost by a method wherein a process, in which a metal film is scraped off by a CMP method is omitted when a multilayer wiring is formed. SOLUTION: The semiconductor device manufacturing method contains a process in which an acid generating agent containing layer 3, containing an acid generating agent which generates an acid by irradiating a light on a board, is formed a process in which an acid is generated on the region where light is selectively made to irradiate on the acid generating agent containing layer 3 through a mask, and a process in which a metal layer 5 is selectively deposited on the region where an acid is generated by a chemical vapor-phase growing method.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method for manufacturing a semiconductor device,
In particular, it relates to multilayer wiring technology.

[0002]

2. Description of the Related Art In recent years, semiconductor manufacturing equipment has been miniaturized and highly integrated, and in particular, wiring tends to be multi-layered.
Along with this, the ratio of the wiring process to the cost is increasing.

Further, in order to make the wiring structure multi-layered, flatness is required, and chemical mechanical polishing (C
A method of flattening an oxide film by a method called MP) has also been proposed. Further, recently, dry etching is difficult depending on the material of the metal wiring, and thus the formation of wiring by the embedded wiring method has been studied. This method is a method in which a groove is formed in an oxide film, a metal film is deposited on the entire surface by a sputtering method or a CVD method, and then an unnecessary portion of metal is removed by a CMP method.

An example of the conventional method for forming the above-mentioned metal wiring will be described below with reference to the drawings.

FIG. 3 is a process chart of a conventional method for manufacturing a metal wiring. In FIG. 3A, 31 is a semiconductor substrate, and 32 is an insulating film deposited on the semiconductor substrate 31. On the insulating film 32, a photosensitive coating insulating film (SO
G) 33 is deposited and is shown in FIG. After that, when pattern exposure is carried out, dehydration and condensation reactions proceed and cure only where the photosensitive coating insulating film 33 is exposed to light (FIG. 3).
(C)).

Subsequently, the portion of the coated insulating film other than the cured portion 34 is dissolved in a solution such as butyl acetate and removed (FIG. 3 (d)). After that, the metal film 35 is deposited on the entire surface by the sputtering method or the CVD method (FIG. 3E). Finally, since the metal other than the groove portion is unnecessary, the excess metal is scraped off by the CMP method to leave the metal only in the groove portion as shown in FIG. 3 (f).

[0007]

However, in the conventional structure as described above, in the process of polishing the metal film by the CMP method, the metal part is rubbed and scraped off in the process of scraping the metal film. However, there is a problem in that the reliability of the metal of the groove portion becomes low. Also, CMP
In the method, there is a problem that the cost of the process itself is high because the pad, slurry, etc. of the consumables are expensive, or the metal is deposited on the entire surface.

In view of the above problems, it is an object of the present invention to provide a highly reliable and low cost semiconductor manufacturing method which simplifies the multi-layer wiring forming step and can omit the step of shaving the metal film by the CMP method. To do.

[0009]

In order to solve the above problems, the present invention forms an acid generator-containing layer by coating a solution containing an acid generator that generates an acid by irradiation with light. The method includes a step, a step of irradiating the acid generator-containing layer with light, and a step of selectively depositing a metal on the light-irradiated portion by a chemical vapor deposition method.

The present invention also includes a step of forming an acid generator-containing layer by coating a solution containing an acid generator which generates an acid by irradiating light on a substrate, and the acid generator-containing layer. A step of depositing a photosensitive resin or a photosensitive glass on it, a step of irradiating the photosensitive resin or the photosensitive glass with light, and a step of irradiating the photosensitive resin or the photosensitive glass with light. The step of dissolving the unexposed portion in a solution and removing to the surface of the acid generator, the step of irradiating the entire surface with light from above the patterned resin, and the step of selectively exposing the exposed portion of the acid generator. It has a structure including a step of depositing a metal on.

[0011]

The present invention has the above steps,
Since the metal can be selectively deposited only on a necessary portion, the CMP process becomes unnecessary, and a highly reliable and low cost multilayer wiring process can be realized.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a process sectional view showing a method for manufacturing a semiconductor device according to a first embodiment of the present invention.
First, in FIG. 1A, 1 is a semiconductor substrate and 2 is an oxide film. Next, as shown in FIG. 1B, the oxide film 2 is coated with an acid generator or a solution containing an acid generator and a silicifying compound to form an acid generator-containing layer. The above-mentioned acid generator-containing layer may have a thickness of several molecular layers, and as the acid generator, for example, those shown below are used.

[0014]

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[0015]

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However, other materials may be used as long as they do not undergo thermal decomposition at about 200 ° C. When a solution containing a silicifying compound and an acid generator is used, heat treatment may be performed at 200 ° C or lower after coating.

After that, as shown in FIG. 1C, light irradiation is performed through a mask to perform pattern exposure, and the pattern is exposed at a desired place where metal is desired to be deposited. In the portion exposed to light, H ⁺ is generated due to the progress of decomposition of the acid generator. Then, metal CVD is performed. As an example, as a raw material gas, DMAH (dimethyl aluminum halide (CH ₃ ) ₂
When AlH) is used, charges are exchanged between the H ⁺ and radicals of methyl (CH ₃ ) only in the portion of the substrate where H ⁺ is generated, gas CH ₄ is generated, and metal Al5 is selected. Are deposited (FIG. 1D). This metal A
15 can be used as it is as a wiring.

As described above, in the present embodiment, the wiring metal can be selectively formed without depositing the metal on the entire surface like the buried wiring and then etching by the CMP method.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a process sectional view showing a method of manufacturing a semiconductor device according to a second embodiment of the present invention.

In FIG. 2A, 21 is a semiconductor substrate,
22 is an oxide film deposited on the substrate. Next, FIG. 2 (b)
As shown in, the oxide film 22 is coated with a solution 23 containing an acid generator or a silicidation compound and an acid generator for several nm. Further, as shown in FIG. 2C, a photosensitive sol-like coated glass film (photosensitive SOG) 24 is deposited thereon. The coated glass 24 is subjected to a pattern exposure, and a dehydration condensation reaction is caused to occur only in a place exposed to light to cure (FIG. 2 (d)). The unreacted portion is dissolved by a solution and removed to form a groove, as shown in FIG. 2 (e). Then, the entire surface is exposed to light to cause decomposition reaction of the acid generator 26 at the bottom of the groove to generate H ⁺ . After that, a metal, for example, aluminum (Al) 27 is selectively embedded by a CVD method only in a portion where H ⁺ is generated to form a wiring (FIG. 2).
(G)). In this case, since the acid generator has a thickness of several nm, the metal is bitten by the reaction of metal deposition to form a wiring.

As described above, also in this embodiment, as in the first embodiment, the metal is once entirely deposited like the buried wiring and then selectively etched without using the CMP method. Wiring metal can be formed.

Although the base of the acid generator is the oxide film 2 in the first embodiment, it may be a metal or a semiconductor. In the first and second embodiments, the metal is aluminum (Al). However, copper (Cu) or gold (A
g) or tungsten (W).

[0024]

As described above, according to the present invention, the step of coating a solution containing an acid generator on a substrate, the step of irradiating the acid generator with light through a mask, and the portion irradiated with the light are described. By providing a step of selectively depositing a metal by a chemical vapor deposition method, a highly reliable and low-cost multilayer wiring can be realized.

[Brief description of drawings]

FIG. 1 is a process sectional view showing a method for manufacturing a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a process sectional view showing a method for manufacturing a semiconductor device according to a second embodiment of the invention.

FIG. 3 is a process sectional view showing a conventional method for manufacturing a semiconductor device.

[Explanation of symbols]

1 Semiconductor Substrate 2 Insulating Film 3 Acid Generating Agent-Containing Layer 4 H ⁺ Generation Area 5 Metal 21 Semiconductor Substrate 22 Insulating Film 23 Acid Generating Agent-Containing Layer 24 Coated Insulation Film 25 Cured Insulation Film 26 H ⁺ Generation Area 27 Metal 31 Semiconductor Substrate 32 insulating film 33 coating insulating film 34 cured insulating film 35 metal

Claims (4)

[Claims] 1. A step of forming an acid generator-containing layer containing an acid generator that generates an acid upon irradiation with light on a substrate, and selectively irradiating the acid generator-containing layer with light through a mask. A method of manufacturing a semiconductor device, comprising: a step of generating an acid in a region irradiated with light; and a step of thereafter selectively depositing a metal layer in the region where an acid is generated by a chemical vapor deposition method. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the acid generator-containing layer further contains a silicifying compound. 3. The semiconductor device according to claim 1, wherein dimethyl aluminum halide is used as a raw material in the step of selectively depositing a metal layer in a region where an acid is generated by the chemical vapor deposition method. Manufacturing method. 4. A step of forming an acid generator-containing layer containing an acid generator that generates an acid upon irradiation with light on a substrate, and a photosensitive resin or a photosensitive glass on the acid generator-containing layer. A step of depositing, a step of selectively irradiating the photosensitive resin or the photosensitive glass with light through a mask to cure an area irradiated with the light, the photosensitive resin or the photosensitive glass And a step of removing a region not exposed to light with a solution, and then irradiating the entire surface with light to remove the acid in the region where the photosensitive resin or the photosensitive glass in the acid generator-containing layer is removed. And a step of selectively depositing a metal layer on a region where an acid has been generated by a chemical vapor deposition method.