JP2624963B2 - Thin film formation method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming a thin film on a substrate.

[Prior Art] For example, in a semiconductor manufacturing process or a thin film magnetic head manufacturing process, a process of forming a thin film on a flat substrate such as a wafer by a vacuum thin film forming technique such as evaporation or sputtering;
The process of processing the formed thin film into a predetermined pattern by etching is repeated. The thin film is formed continuously over the entire surface of the substrate.

[Problems to be Solved by the Invention] However, when a thin film is formed continuously over the entire surface of the substrate and the area thereof is increased, the stress of the thin film increases, and the substrate may be warped or distorted. is there. FIG. 3 shows a state in which the substrate is warped in this manner, wherein reference numeral 1 denotes a substrate, and reference numeral 3 denotes a thin film.

If the warpage or distortion is large, the substrate may be cracked or the thin film may be peeled off. Further, there is a problem that the substrate cannot be vacuum-chucked even if the warpage and distortion are not so large, and that unevenness in exposure occurs during patterning exposure by photolithography. That is, the stress of the thin film causes the yield to decrease in the process of forming the thin film.

In many cases, the film forming conditions under which the characteristics of the thin film are optimized and the conditions under which the stress state of the thin film is optimized do not match.
There is also a problem that it is necessary to sacrifice the characteristics of the thin film in consideration of the stress of the thin film when determining the film forming conditions.

[Means for Solving the Problems] To solve such problems, according to the present invention, in a thin film forming method for forming a thin film on a substrate, a film forming surface of the substrate is divided into required areas. In order to achieve this, a groove having a depth greater than the thickness of a thin film formed in a subsequent step or a ridge having a height greater than the thickness of the thin film is formed on the film-forming surface of the substrate, and thereafter, the film is formed on the substrate. By forming the thin film on the surface, the thin film is formed on the film forming surface by being divided at the required area by the step of the groove or the ridge when the thin film is formed.

[Operation] According to such a method, since the thin film is divided and formed, the stress of the entire thin film is dispersed and reduced. Then, problems due to the stress of the thin film can be avoided. In addition, the film forming conditions can be determined by giving priority to the characteristics of the thin film without considering the stress of the thin film, and a thin film having excellent characteristics can be formed.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

First Embodiment FIGS. 1A to 1C illustrate a thin film forming process according to a first embodiment of the present invention.

In FIG. 1A, reference numeral 1 denotes a substrate (or wafer), and the upper surface in the figure is a film forming surface on which a thin film is formed. In this embodiment, before forming a thin film on the film forming surface of the substrate 1, a groove indicated by reference numeral 2 is formed in advance by dicing or etching. The groove 2 has a rectangular cross section and is formed in a linear shape with a narrow width, and divides the film-forming surface of the substrate 1 for each required area, that is, is formed at a predetermined pitch, and its depth is formed next. It should be much larger than the thickness of the thin film.

Next, as shown in FIG. 1 (B), a thin film 3 is formed on the substrate 1 by a vacuum thin film forming technique such as evaporation or sputtering.

At this time, the thin film 3 is divided and formed via the step of the groove 2. That is, as shown in an enlarged manner in FIG.
Since the thin film 3 hardly adheres to 2a, the thin film 3 is divided at this portion.

In this embodiment, since the thin film 3 is divided and formed as described above, the entire stress of the thin film 3 is dispersed and reduced. For this reason, it is possible to prevent the occurrence of warpage or distortion of the substrate 1 due to the stress of the thin film 3 and also to prevent the occurrence of peeling of the thin film. Further, the production yield of various products manufactured by the process including the thin film forming process can be improved. Further, according to the present embodiment, the problem of the stress of the thin film 3 can be avoided. Therefore, when deciding the film forming conditions of the thin film 3, the problem of the characteristic of the thin film 3 is given priority without much considering the stress problem. In consideration of this, it is possible to form a thin film 3 having excellent characteristics.

Second Embodiment Next, FIGS. 2A to 2C illustrate a thin film forming process according to a second embodiment of the present invention.

In this embodiment, first, a ridge indicated by reference numeral 4 is formed before a thin film is formed on the upper surface of the substrate 1 shown in FIG. The ridges 4 are formed in a thin line with a rectangular cross section at a predetermined pitch, and divide the film formation surface of the substrate 1 into required areas. The height of the ridge 4 is sufficiently larger than the thickness of a thin film to be formed later. The ridges 4 are formed of, for example, a striped thin film. The material of the thin film of the ridge 4 is not particularly limited, for example, a polymer compound such as a photoresist, a metal, an inorganic substance, or the like.

After forming such ridges 4, a thin film 3 is formed on the upper surface in the figure as a film forming surface of the substrate 1 by a vacuum thin film forming technique or the like as shown in FIG. 2 (B). Here, the thin film 3 is a ridge 4
Are formed by being divided by the step. That is, FIG. 2 (C)
As shown in the enlarged view, the thin film 3 hardly adheres to both side surfaces 4a of the ridges 4 substantially perpendicular to the film forming surface on the upper surface in the figure of the substrate 1, so that the thin film 3 is divided at this portion. .

As described above, in this embodiment, the thin film 3 is formed by being divided, and the same operation and effect as those of the first embodiment can be obtained.

By selecting a material that can be etched separately from the thin film 3 as the material of the ridge 4, the ridge 4 can be formed after the thin film 3 is formed.
Can also be removed.

In the above-described first and second embodiments, the groove 2 or the ridge 4 is formed and the thin film 3 is divided.
It is also conceivable that the thin film 3 is divided by forming a combination of

[Effects of the Invention] As is apparent from the above description, according to the present invention, in a thin film forming method for forming a thin film on a substrate, a post-process is performed to divide a film forming surface of the substrate into required areas. Forming a groove having a depth greater than the thickness of the thin film formed on the substrate or a ridge having a height greater than the thickness of the thin film on the film forming surface of the substrate, and then forming a thin film on the film forming surface of the substrate By adopting a configuration in which the thin film is formed so as to be divided into the required area on the film forming surface by the step of the groove or the ridge when the thin film is formed,
The stress of the formed thin film can be dispersed and reduced, and problems such as warping, distortion, cracking, and peeling of the thin film due to the stress of the thin film can be prevented. In addition, it is possible to reduce the cost of products that can improve the yield of products manufactured in the process including the thin film forming process. In addition, the film forming conditions of the thin film can be determined without considering the stress of the thin film, and a thin film having excellent characteristics can be formed.

[Brief description of the drawings]

1 (A) to 1 (C) are explanatory views of a thin film forming process according to a first embodiment of the present invention, and FIGS. 2 (A) to 2 (C).
FIG. 3 is an explanatory view of a thin film forming process according to a second embodiment of the present invention, and FIG. 3 is an explanatory view of substrate warpage due to thin film stress. DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Groove 3 ... Thin film, 4 ... Rib

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisashi Hayashi 1248 Shimokage Mori, Chichibu City Canon Electronics Co., Ltd. (72) Inventor Mitsuo Nakahashi 1248 Shimokage Mori Chichibu City, Oaza Inventor Takeshi Osato 1248 Shimokagemori, Chichibu-shi Canon Electronics Co., Ltd. (56) References JP-A-59-197568 (JP, A) JP-A-57-145319 (JP, A) JP-A-59-170270 (JP, A) Japanese Patent Publication No. 55-2736 (JP, B2) Jiko 49-14764 (JP, Y1)

Claims (2)

(57) [Claims] 1. A thin film forming method for forming a thin film on a substrate, wherein a groove having a depth greater than a thickness of a thin film formed in a subsequent step is formed to divide a film forming surface of the substrate into required areas. A ridge having a height greater than the thickness of the thin film is formed on the film-forming surface of the substrate, and then a thin film is formed on the film-forming surface of the substrate. The method for forming a thin film, wherein the thin film is formed on the film forming surface by being divided into the required areas. 2. The ridge is formed of a thin film different from the thin film formed on the film forming surface, and after forming the thin film on the film forming surface, the ridge is removed. The method for forming a thin film according to claim 1.