JPS6340321A - Formation of pattern - Google Patents

Abstract

PURPOSE:To easily remove an inorganic mask layer after treatment on the occasion of formation of a pattern by etching, by forming the inorganic mask layer and a photoresist layer in lamination on the surface of a substrate with an organic material layer soluble in a solvent interposed in between. CONSTITUTION:An organic material layer 6 is formed on a substrate 1, and an intermediate inorganic mask layer 5 is formed on the layer 6 by evaporation or the like. Next, a photoresist is applied on the layer 5, and a photoresist pattern 4 is formed by exposure, development and baking. Then, the layer 5 is etched, and further the layer 6 is etched. With the obtained pattern used as a mask, the substrate 1 is etched, the layer 6 is dissolved thereafter by a solvent for dissolution, and the layer 5 is also removed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pattern forming method that is advantageous for forming fine patterns necessary for semiconductor devices and the like.

[Conventional technology]

Conventionally, resist pattern formation using photolithography technology has been used as a method for forming fine patterns in, for example, semiconductor devices. This is the second −(a1
As shown in Figures ~ (c1), a photoresist 2 made of a photosensitive resin is applied to a processing material, for example, a substrate 1.
(Figure aJ), this is partially exposed to ultraviolet light etc. using a photomask 3t [Figure 2-(b)], and then developed and baked to form a photoresist pattern 4 [Figure 2-(C
)) Using the obtained photoresist pattern as a mask, the substrate is processed by etching, ion implantation vapor deposition, CVO method, etc.

However, photoresist patterns do not have sufficient durability as a mask when etching a substrate deeply. Therefore, when performing deep etching, a metal pattern forming method as shown in FIG. 5 has been used. In Figures 5-(a) to 3-(C1), first, for example, an AI is applied to the substrate 1.
! , Tl, Ni.

An inorganic mask layer 5 of SiO2, Si3N4, etc. is deposited [5-(Figure a1)], and a resist is coated on the upper surface of the inorganic mask layer 5 to form a photoresist pattern 4t in the same manner as in Figure 2. [5th-(Figure b1)] Next, remove unnecessary layers by etching [5th-fcl[i9]
] method. This improves the resistance of the mask and makes it possible to perform deeper etching than with the photoresist method. The white arrow in Figure 3-(cJ) means etching.

[Problem that the invention seeks to solve]

However, the metal pattern forming method has a problem in that it is difficult to remove metals such as A/, Tl, and 11 after processing. 810 back to metal again
2, SL, or N4t masks can be easily removed with HF, but when the substrate is 81 or SiO□, there is a problem that the substrate is etched.

It is an object of the present invention to overcome these drawbacks of the prior art and to provide a new method that allows a thicker mask to be formed and the mask layer to be easily removed after processing is completed.

[Means for solving problems]

Instead of the conventional method of depositing an inorganic mask layer directly onto a substrate, the present inventors first coated an organic material on the substrate and then formed an inorganic mask layer thereon by vapor deposition at room temperature. The present invention was achieved by discovering that the nine drawbacks could be solved.

The present invention provides a method of laminating and forming an inorganic mask layer and a photoresist layer on the surface of a substrate, exposing the layer partially to light, developing and baking it, and then removing unnecessary portions to form a pattern. This pattern forming method is characterized by providing an organic material layer between mask layers.

In the present invention, a particularly preferred embodiment is that the organic material layer is made of an organic material soluble in a dissolving solvent, and that the inorganic mask layer is removed by dissolving and removing it after processing.

The pattern forming method of the present invention will be explained with reference to FIGS. (Fig. a1), an intermediate inorganic mask layer 5 is formed on the upper surface of the organic material layer 6 by, for example, vapor deposition or CVO method [Fig. Then, pattern formation is performed using known methods such as exposure, development, and baking [Fig. +-(c)].

Next, unnecessary portions of the intermediate inorganic mask layer 5 are removed by etching, etc. [No.
Form +-(e)oL desired pattern. Based on the obtained pattern, etching, ion implantation,
Processing such as vapor deposition or CVO method is performed, and after the processing is completed, the mask layer is removed by removing the organic material layer 6.

As described above, in the present invention, after applying an organic material to the surface of a substrate, an inorganic mask layer and a photoresist layer are formed thereon, thereby obtaining a mask with improved resistance that allows processing such as deep etching. In addition, by removing the organic material after processing is completed, the inorganic mask layer can be easily removed, which was difficult with conventional methods. In particular, if an organic material that is soluble in a dissolving solvent is used, it can be easily removed.

In the present invention, examples of the organic material layer provided between the inorganic mask layer and the substrate include silicone resin, novolac resin,
Vinylidene heptadide resin, polyimide, photoresist, etc. are preferred, and photoresist, such as Az
-+550J (manufactured by Hoechst Japan), WAYOA
Photoresists commercially available under trade names such as T HRR series and HNR series (manufactured by Fuji Hunt Chemical Co., Ltd.), 0FPR series, OMR85 (manufactured by Tokyo Ohka Co., Ltd.) and Microposite (manufactured by Sibley 7 Earth Co., Ltd.) may be mentioned. Examples of methods for removing these organic material layers include 02 plasma etching and dissolution using a dissolving solvent such as a commercially available resist stripping solution, sulfuric acid, and the like.

Examples of the intermediate inorganic mask layer used in the present invention include kl,
Tz, N1. SLO□, 813N4, etc. are preferable, and these inorganic mask layers may be formed by known techniques such as vapor deposition, sputtering, (VD), etc.

〔Example〕

Example 81 Photoresist [Tokyo Ohka (4$1811, oyR83:] i thickness 1.0 μtn) as an organic material on a substrate
After coating, the resist was heated at 85C for 25 minutes to remove the solvent of the resist. At this time, if the temperature is raised too high, the resist will harden and be difficult to remove, so the temperature should be 85C ± 5CK.
Managed. Next, the entire surface of the organic material layer is exposed to UV light (t0). Next, an inorganic mask layer is formed using AI! Fully vapor deposited. The substrate temperature was kept at room temperature, and the thickness of the A layer was set to 2 μm.

Photoresist AZ 1550J is applied on the top surface of the inorganic mask layer.
(manufactured by Hoechst Japan) and exposed using a conventional method.
Development and baking were performed to form a photoresist pattern.

Using this photoresist pattern as a mask, the Aj layer is etched using a fully parallel plate type etching device. The conditions at this time are BCI3f Q seam, 5 Pa,
2 Q Q W, about 10 minutes and then. This allows the input
A pattern was formed.

Next, using the above-mentioned Al pattern as a mask, the organic material (0MR85) layer was die-etched using a parallel plate type etching device. The conditions at this time were 0210 secm and 5Pa.

The power was 200 W for about 5 minutes. Using the obtained pattern as a mask, the substrate S1 was etched by 20 μm in the depth direction.

After that, AI! was made into an inorganic mask layer! To remove 0-dichlorobenzene (Tokyo Ohka, Peeler Liquid 502)
) When ultrasonic waves were applied inside the sample, the organic material layer was dissolved and the diA/ layer was easily peeled off.

As described above, by the method of the present invention, the substrate S1f: 20μ
Etching can be performed deeply up to m, and L after machining is completed.
/ It can be seen that the mask layer can be easily removed.

〔Effect of the invention〕

In the pattern forming method of the present invention, when processing a substrate, a layer of organic material that is easily peeled off is first provided on the surface of the substrate, and then an inorganic mask layer is attached to form a pattern. The removal of the inorganic mask layer after processing, which was difficult with the formation method, can be easily done by using a solvent that dissolves the organic materials mentioned above. By improving the etching process, deep etching is possible.

[Brief explanation of the drawing]

Figures 1 (1L), (bl, (cl, fd) and (6) are cross-sectional views explaining the pattern forming method of the present invention in the order of steps. Figure 2 ('L) (bl and (C1 are conventional A cross-sectional view explaining the photoresist method. FIGS. 3A, 3B, and 3C are cross-sectional views explaining the conventional metal pattern forming method.

Claims (3)

[Claims] (1) In a method in which an inorganic mask layer and a photoresist layer are laminated and formed on the surface of a substrate, this is partially exposed, developed and baked, and unnecessary portions are removed to form a pattern. A pattern forming method characterized by providing an organic material layer between inorganic mask layers. (2) The pattern forming method according to claim (1), wherein the organic material layer is made of an organic material soluble in a dissolving solvent. (3) The pattern forming method according to claim (1), wherein the inorganic mask layer is removed by dissolving the organic material layer in a dissolving solvent after finishing the processing.