JPH0424923A - Semiconductor device - Google Patents

Abstract

PURPOSE:To improve a step generated on multilayer interconnections and to flatten its surface by forming an interconnection groove in which first layer interconnection is entirely or partly buried on an insulating film under the first layer interconnection, and burying the first interconnection. CONSTITUTION:An interconnection groove 6 in which a first layer interconnection 3 can be entirely or partly buried is provided on an insulating film 2 under the interconnection 3, and the interconnection 3 is buried to alleviate a step of an interlayer insulating film 4. Further, even if a second layer interconnection 5 is crossed at the part, the flatness of a semiconductor surface is held, and the fault of the interconnection at the step can be reduced. When the interconnection 3 is buried in the groove 6 and covered with a protective film 7, a stress to be applied to the interconnection 3 can be absorbed in the manufacture of the semiconductor, and distortions of the interconnection due to a stress generated at the four corners of a semiconductor device can be alleviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor device that improves steps caused by multilayer wiring and alleviates distortion due to stress applied to the wiring during the semiconductor manufacturing process.

[Conventional technology]

FIG. 5 is a sectional view of a conventional semiconductor device having multilayer wiring. In this figure, 1 is a semiconductor substrate,
2 is an insulating film under the wiring, 3 is a first layer wiring, 4 is an interlayer insulation film between the first layer wiring 3 and the second layer wiring, and 5 is a second layer wiring.

In the semiconductor device configured in this way, the first layer wiring 3 is deposited on the insulating film 2, and the portion where the first layer wiring 3 is arranged is equal to the thickness (height) of the wiring. A difference in level occurs.

Therefore, the thickness of the multilayer wiring also increases accordingly.

[Problem to be solved by the invention]

Since the conventional semiconductor device having multilayer wiring is configured as described above, the portion where the first layer wiring 3 is arranged is
If a step occurs in the upper layer due to the thickness of the first layer wiring 3 and the second M wiring 5 intersects with that portion, the formation of the second layer wiring 5 is not easier due to the step than in a flat area. .

Furthermore, in the case of only one layer of wiring without wiring in the upper layer, there are problems such as distortion (sliding) of the wiring due to stress applied to the wiring at the four corners of the semiconductor device.

This invention was made in order to solve the above-mentioned problems, and aims to improve the level difference caused by multilayer wiring and to obtain a semiconductor device that takes measures against sliding of wiring due to stress. [Means for Solving the Problems] A semiconductor device according to the present invention includes forming a wiring groove in which the first layer wiring is entirely or partially buried in an insulating film under the first layer wiring, and a first layer wiring groove in which the first layer wiring is buried. One layer of wiring is buried.

[Effect]

In this invention, the first layer wiring is completely or partially buried in the wiring groove provided in the lower insulating film, and the level difference is eliminated accordingly.

Further, even when there is no wiring in the upper layer, by burying the first layer wiring in the wiring groove, strain (sliding) due to stress applied to the wiring in subsequent manufacturing of the semiconductor device is alleviated.

〔Example〕

FIG. 1 is a sectional view of a semiconductor device showing an embodiment of the present invention, and FIG. 2 is a plan view of FIG. 1.

In these figures, 1 to 5 are equivalent to those shown in FIG. 5, and 6 is a wiring groove formed in the insulating film 2, and the first layer wiring 3 is buried in this wiring groove 6. Ru. In addition,
The depth of this wiring trench 6 is formed such that the first layer wiring 3 is buried in whole or in part.

In a semiconductor device having multilayer wiring as shown in FIG.
A wiring groove 6 in which the first layer wiring 3 can be completely or partially buried is provided in the insulation #2 under the first layer wiring [3, and the step difference in the interlayer insulating film 4 is formed by burying the first layer wiring 3. Further, even if the second layer wiring 5 intersects with that portion, the flatness of the semiconductor surface is maintained, and disconnection of the wiring at the stepped portion can be reduced.

FIG. 3 is a sectional view of a semiconductor device showing another embodiment of the invention, and FIG. 4 is a plan view of FIG. 3. This embodiment is a case where only the first layer wiring 3 has no wiring in the upper layer.

In this semiconductor device, a first layer wiring 3 is buried in a wiring trench 6 and covered with a protective film 7. In this case, the stress applied to the first layer wiring 3 during subsequent semiconductor manufacturing can be absorbed, and the distortion (sliding) of the wiring due to the stress generated at the four corners of the semiconductor device can be alleviated.

〔Effect of the invention〕

As explained above, the present invention forms a wiring groove in which the first layer wiring is buried in whole or in part in the insulating film under the first layer wiring, and buries the first layer wiring in the wiring groove B. So,
It improves the level difference that occurs in multilayer wiring and makes the surface flattened, making it easier to manufacture semiconductor devices. In addition, improved glabellar pressure resistance,
This has the effect of improving reliability, such as reducing aluminum migration.

Further, even in the case of the first layer wiring, there is an effect that a semiconductor device that can prevent the (aluminum) wiring from sliding can be obtained.

[Brief explanation of the drawing]

The first factor is a sectional view of a semiconductor device showing one embodiment of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a sectional view of a semiconductor device showing another embodiment of the invention. 4 is a plan view of FIG. 3, and FIG. 5 is a sectional view showing a conventional semiconductor device. 4 is a first layer wiring, 4 is an interlayer insulating film, 5 is a second layer wiring, and 6 is a wiring trench. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent: Masuo Oiwa (2 others)

Claims (1)

[Claims] In a semiconductor device in which at least a first layer wiring is formed on an insulating film on a semiconductor substrate, a wiring groove in which the first layer wiring is buried in whole or in part is formed in the insulating film below the first layer wiring. . A semiconductor device, characterized in that the first layer wiring is buried in the wiring groove.