JPH04298049A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To provide a metalized fine electrode pattern, having low wiring resistance, on a substrate using resist. CONSTITUTION:A T-groove is formed in a photoresist 2 with a masking film 3 deposited over it. After the masking film 3 is removed, a metal film is deposited, and then an electrode pattern 4' having a T-shaped cross section by a lift-off technique.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device, and more particularly to an improvement in a method of forming a wiring pattern using a resist.

0002

2. Description of the Related Art FIG. 2 is a cross-sectional view showing the manufacturing flow of a conventional semiconductor device manufacturing method. After patterning (FIG. 2(a)), the substrate 1 is etched using the photoresist 2 as a mask (FIG. 2(b)), then wiring metal is deposited on the entire surface of the substrate (FIG. 2(c)), and then Lift-off (Figure 2(d)
) to pattern an arbitrary metal 3 on the substrate. Note that in the above process, if no groove is provided in the substrate, the etching process (FIG. 2(b)) is not necessary.

As shown in FIG. 2(d), the metal pattern 4 patterned by the above method has a line width determined by the opening width of the resist pattern 2, and a cross-sectional shape determined by the shape of the resist pattern. It becomes trapezoidal.

0004

[Problems to be Solved by the Invention] Since the conventional semiconductor device manufacturing method is configured as described above, the cross-sectional shape of the resulting wiring pattern is trapezoidal, so when the pattern line width becomes small, There were problems in that the cross-sectional area became smaller and the wiring resistance increased.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method for manufacturing a semiconductor device in which the cross-sectional area of wiring does not become small even when finely patterned.

[0006]

[Means for Solving the Problems] A method for manufacturing a semiconductor device according to the present invention provides a photoresist pattern formed on a substrate with a deposited film having a thickness thinner than that of the resist, and etches the sidewalls of the resist pattern to form a photoresist pattern. After forming a T-shaped groove, a T-shaped metal pattern is formed by vapor deposition and lift-off.

[0007]

[Operation] In this invention, after processing a photoresist using conventional photolithography, a vapor deposited film thinner than the photoresist is formed, and the pattern sidewalls of the photoresist are removed using this as a mask. Since the photoresist pattern is processed to provide a T-shaped groove, the cross section of the metal pattern obtained by vapor depositing and lifting off the photoresist pattern as a mask becomes T-shaped.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The figure is a flow cross-sectional view showing a method for manufacturing a semiconductor device according to an embodiment of the present invention. The same reference numerals as in FIG. It is.

Next, the manufacturing method will be explained. Figure 1 (a
) As shown in the conventional example, a photoresist 2 is applied onto a semiconductor substrate 1, and the photoresist is patterned by an arbitrary method. Then, as shown in FIG. 1(b), a metal or dielectric material 3 such as SiOx, which is thinner than the photoresist 2, is deposited on the entire surface of the substrate, and the upper surface of the photoresist 2 and a part of the side surface of the opening on the substrate side are covered with the metal or dielectric material 3. Masking is performed.

Next, using this metal or dielectric material 3 as a mask, the side wall portion of the resist 2 (area A shown in FIG. 1(c)) is removed by isotropic etching such as plasma ashing, and then the metal or dielectric material 3 is removed. When removed, a T-shaped groove is formed in the photoresist 2. In this state, the substrate 1 is etched (see FIG. 1(d)) to form the groove, and as shown in FIG. 1(e).
As shown in FIG. 1, an electrode metal 4 is deposited on the entire surface of the substrate and patterned by lift-off to obtain an electrode 4' having a T-shaped cross section as shown in FIG. 1(f).

According to this embodiment, after patterning the photoresist 2 on the substrate 1, a metal or dielectric material 3 thinner than the photoresist 2 is deposited on the entire surface, and the resist 2 is etched using this as a mask. The sidewalls of the pattern of the resist 2 are removed and the cross section of the resist 2 is processed to have a T-shaped groove. When the electrode metal 4 is evaporated using this resist and lifted off, a T-shaped cross section is formed. The electrode 4' is obtained, the cross-sectional area of the electrode is increased compared to the conventional method, and a wiring pattern with low wiring resistance can be obtained even when miniaturized.

[0012] As a method for removing the A area of the resist 2 in Fig. 1(c), the substrate 1 is exposed to light using the dielectric 3 as a mask, the A area is exposed to light due to the diffraction phenomenon of light, and then developed. There is also a method of removing the A area.

In addition, when no groove is provided in the substrate 1, as shown in FIG.
The etching step in step d) can be omitted.

[0014]

As described above, according to the method of manufacturing a semiconductor device according to the present invention, after masking a part of the photoresist pattern on the substrate with a vapor-deposited film, part of the photoresist is removed and the photoresist pattern is removed. Since the resist was processed into a T-shape, a metal pattern was vapor-deposited using this photoresist as a mask.
When formed by lift-off, a T-shaped pattern with a large cross-sectional area is formed even in a fine pattern, and there is an effect that a metal pattern with low wiring resistance can be obtained.

[Brief explanation of drawings]

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

FIG. 2 is a process cross-sectional view showing a conventional method for manufacturing a semiconductor device.

[Explanation of symbols]

1 Semiconductor substrate 2 Photoresist 3 Metal or dielectric film (deposited film) 4 Metal film for electrode pattern 4' Metal film for electrode pattern

Claims (1)

[Claims] Claim 1: A method for manufacturing a semiconductor device comprising a step of coating a resist on a substrate and patterning it, then vapor depositing metal on the entire surface and lift-off to form a metal electrode pattern, after patterning the resist on the substrate. ,
a step of providing a vapor deposited film thinner than the resist over the entire surface; a step of etching away a part of the resist using the vapor deposited film as a mask to form a groove with a T-shaped cross section in the resist; and after removing the vapor deposited film, 1. A method for manufacturing a semiconductor device, comprising the steps of depositing a metal pattern on the entire surface and performing lift-off to form a metal electrode pattern.