JPH06167802A - Production of phase shift mask - Google Patents

Abstract

PURPOSE:To provide a method for producing a phase shift mask by which a shifter pattern can easily be formed on a glass substrate as a base with high selectivity. CONSTITUTION:Polycrystalline silicon is deposited on a mask pattern 11 formed on a glass substrate 1 to form a polycrystalline silicon film 12, this film 12 is selectively etched to form a desired polycrystalline silicon pattern 14 and then a shifter pattern 15 is formed by oxidizing the pattern 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing method for forming a phase shifter mask in a phase shift mask.

[0002]

2. Description of the Related Art A conventional phase shift mask of this type is manufactured through steps shown in FIG. Hereinafter, a conventional method of manufacturing a phase shift mask will be described with reference to the drawings. First, as shown in FIG. 3A, the glass substrate 1
A silicon nitride film (Si ₃ N ₄ film) is formed as a stopper material 2 for forming a shifter pattern, and a mask pattern material 3 such as a Cr film is formed thereon. next,
As shown in FIG. 3B, a photoresist pattern 4 for forming a mask pattern is formed on the mask pattern material 3
To form a desired pattern.

After etching the stopper material 2 using the photoresist pattern 4 as a mask,
The photoresist pattern 4 is removed by ashing (ashing process) to form a mask pattern 5 as shown in FIG. Next, as shown in FIG. 3D, a shifter material 6 made of, for example, an inorganic coating film (SOG film) or the like is formed on the mask pattern 5. Thereafter, as shown in FIG. 3E, a photoresist pattern 7 is formed on the shifter material 6 as a shifter material processing mask. And
By using the photoresist pattern 7 as a mask, the shifter material 6 is etched with a high selectivity by the stopper material 2 with respect to the glass substrate 1, and finally the photoresist pattern 7 is removed. The shifter pattern 8 is formed as shown in FIG. 6 and the manufacturing process of the phase shift mask is completed.

[0004]

Since the conventional method for manufacturing a phase shift mask is performed through the above steps, a high selectivity ratio with respect to the underlying glass substrate 1 is obtained when the shifter pattern 8 is processed. Glass substrate 1 as required
There has been a problem that the stopper material 2 such as a Si ₃ N ₄ film or an Al ₂ O ₃ film has to be provided on the top, and controllability at the time of processing is required.

The present invention has been made to solve the above problems, and provides a method of manufacturing a phase shift mask capable of easily forming a shifter pattern with a high selection ratio on a glass substrate as a base. It is intended to be provided.

[0006]

[Means for Solving the Problems] Claim 1 according to the present invention
In the method of manufacturing a phase shift mask of, a polycrystalline silicon film is formed by depositing polycrystalline silicon on a mask pattern formed on a glass substrate, and the polycrystalline silicon film is etched in a selective ratio with respect to the substrate. Is performed to form a desired polycrystalline silicon pattern, and the polycrystalline silicon pattern is oxidized to form a shifter pattern.

According to a second aspect of the method of manufacturing a phase shift mask, a desired photoresist pattern is formed on a mask pattern formed on a glass substrate, and impurity ions are introduced into the glass substrate from the photoresist pattern. After implantation to form an impurity implantation layer, the photoresist pattern is removed by ashing, and then the impurity implantation layer is etched in a highly selective ratio with respect to the glass substrate to form a shifter inversion pattern. is there.

[0008]

The polycrystalline silicon film deposited on the glass substrate according to claim 1 of the present invention is etched in a highly selective ratio with respect to the glass substrate to form a shifter pattern,
Further, the impurity-implanted layer formed by implanting impurity ions into the glass substrate according to the second aspect is etched in a highly selective ratio with respect to the glass substrate to form a shifter inversion pattern.

[0009]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing each step of the method for manufacturing a phase shift mask in the first embodiment of the present invention. First, as shown in FIG. 1A, a mask pattern material 9 is formed on the glass substrate 1. Then, a desired photoresist pattern 10 is formed on the mask pattern material 9 as a mask for mask pattern processing.
As shown in (B), this photoresist pattern 10
Using the as a mask, the mask pattern material 9 is etched.

Next, the photoresist pattern 10 is removed by ashing to form a mask pattern 11 as shown in FIG. Then, a polycrystalline silicon film 12 for forming a shifter pattern is formed so as to cover the mask pattern 11 on the substrate 1 by a chemical vapor deposition method as shown in FIG. ), A desired photoresist pattern 13 is formed on the polycrystalline silicon film 12 as a mask for shifter pattern processing.
To form. Then, this photoresist pattern 13
The polycrystalline silicon film 12 is used as a mask for the glass substrate 1
Then, the photoresist pattern 13 is removed by ashing after this etching, and a polycrystalline silicon pattern 14 is formed as shown in FIG. Finally, the polycrystalline silicon pattern 14 is subjected to an oxidation treatment to form a shifter pattern 15 made of a silicon oxide film as shown in FIG. Therefore, unlike the conventional case, it is not necessary to provide a stopper material, so that controllability at the time of processing is not required and the manufacturing becomes easy.

Embodiment 2. In the first embodiment, the shifter pattern 15 is formed by using the polycrystalline silicon film 12 as the material of the shifter pattern 15 to obtain a high selectivity with the underlying glass substrate 1. Impurities such as phosphorus (P) are injected into the glass substrate 1,
The shifter pattern can also be formed by etching away the impurity-implanted layer with respect to the glass substrate 1 with high selectivity.

The steps of the method of manufacturing the phase shift mask in the second embodiment of the present invention will be described below with reference to FIG. First, although not shown in FIG.
2A and 2B through the same processing steps as shown in FIGS.
As shown in (A), the mask pattern 1 is formed on the glass substrate 1.
6 is formed. Then, as shown in FIG. 2 (B), a photoresist pattern 17 for forming a shifter pattern is formed on the substrate 1 so as to leave a part of the mask pattern 16 and cover the other part, and the photoresist is formed. Using the pattern 17 as a mask, impurities such as phosphorus (P) are ion-implanted into the substrate 1 as shown by an arrow in the figure, to form an impurity-implanted layer 18. After that, Figure 2
As shown in FIG. 2C, the photoresist pattern 17 is removed by ashing, and finally, as shown in FIG. The shifter reversal pattern 19 can be processed by performing wet etching using it, and the shifter pattern 20 is formed by processing the shifter reversal pattern 19.

[0013]

As described above, according to claim 1 of the present invention, polycrystalline silicon is deposited on a mask pattern formed on a glass substrate to form a polycrystalline silicon film, and the polycrystalline silicon film is formed. The desired pattern of polycrystalline silicon is formed on the substrate by selective etching, and the pattern of the polycrystalline silicon is oxidized to form the shifter pattern. According to the above, a desired photoresist pattern is formed on a mask pattern formed on a glass substrate, and impurity ions are injected into the glass substrate from the photoresist pattern to form an impurity injection layer. After removing the ashing process, the impurity-implanted layer is etched with a high selective ratio with respect to the glass substrate. Since so as to form a rolling pattern, it is possible to provide a manufacturing method for easily high selectivity can be formed shifter pattern phase shift mask to the glass substrate as a base.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing each step of a method for manufacturing a phase shift mask in Example 1 of the present invention.

FIG. 2 is a schematic cross-sectional view showing each step of a method for manufacturing a phase shift mask in Example 2 of the present invention.

FIG. 3 is a schematic cross-sectional view showing each step of a conventional phase shift mask manufacturing method.

[Explanation of symbols]

 1 Glass Substrate 9 Mask Pattern Material 10, 13, 17 Photoresist Pattern 11, 16 Mask Pattern 12 Polycrystalline Silicon Film 14 Polycrystalline Silicon Pattern 15, 20 Shifter Pattern 18 Impurity Injection Layer 19 Shifter Inversion Pattern

Claims (2)

[Claims] 1. A step of depositing polycrystalline silicon on a mask pattern formed on a glass substrate to form a polycrystalline silicon film, and the polycrystalline silicon film is selectively etched with respect to the substrate. A method of manufacturing a phase shift mask, comprising: a step of forming a desired polycrystalline silicon pattern; and a step of forming a shifter pattern by oxidizing the polycrystalline silicon pattern. 2. A step of forming a desired photoresist pattern on a mask pattern formed on a glass substrate, and ion implantation of impurities from the photoresist pattern into the glass substrate to form an impurity implantation layer. A step of removing the photoresist pattern by an ashing process, and a step of forming a shifter inversion pattern by etching the impurity implantation layer with a high selective ratio with respect to the glass substrate, Of manufacturing a phase shift mask.