JPH0691034B2 - Method for manufacturing semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] In the method for manufacturing a semiconductor device, the present invention corresponds to a peripheral edge portion of a laser light irradiation region when Al formed on the via hole is melted by laser light irradiation to fill the via hole. In order to eliminate the inconvenience that high quality semiconductor chips cannot be produced due to so-called twisting in the conductive layer, the peripheral edge of the laser light irradiation area should face the outside of the area where the integrated circuit is formed in the semiconductor chip. By irradiating with a laser beam, a high quality semiconductor chip free from the surface is obtained.

[Industrial application field]

The present invention relates to a method of manufacturing a semiconductor device, and more particularly, to a method of manufacturing a semiconductor device in which an Al deposited film is melted and embedded in a via hole (a generic term for a contact hole and a through hole) by pulsed laser light irradiation.

[Background of technology]

FIG. 3 shows a sectional view of depositing Al in the via hole. 1 is
Si substrate, 2 is an interlayer insulating film, and 2a is a via hole. When depositing Al3 in the via hole 2a, if a method such as sputtering or vapor deposition is used, particularly in the case of a via hole having a high aspect ratio (depth / diameter), as shown in FIG. Is poor, and poor connection with the Si substrate 1 is likely to occur. Similarly, in the multilayer Al wiring structure, a connection failure between the upper layer Al wiring and the lower layer Al wiring is likely to occur.

In order to prevent such a connection failure, the pulse laser beam 4 is irradiated from above the Al3 so that the Al3
It is conceivable that the via hole 2a is filled with the aluminum oxide by melting it to form the Al layer 3a.

However, in general, as shown in FIG. 4, the Al layer 6 corresponding to the peripheral edge portion of the pulse laser spot region 5 has an increased film thickness to produce a so-called "strand" 6a, which can form a flat chip surface. Absent. In particular, when one side of the area for one semiconductor chip is A, the use of the pulsed laser light having the area 5 in which the "strand" 6a is included in the area of the one side A provides a high quality semiconductor device. There is an inconvenience.

[Means for Invention]

In the method of manufacturing a semiconductor device according to the present invention, as shown in FIG. 1, the laser light is irradiated so that the peripheral edge portion of the laser light irradiation region 11 is outside the region 7 where the integrated circuit is formed in the semiconductor chip.

[Action]

Since the peripheral edge of the laser beam irradiation area is outside the area where the integrated circuit is formed in the semiconductor chip,
It is possible to obtain a high-quality semiconductor chip without "twist" on the surface.

〔Example〕

FIG. 2 shows a diagram in which the laser spot region is aligned with the semiconductor chip. In FIG. 1A, 7 is a region in which an integrated circuit is formed in one semiconductor chip, and the region is indicated by diagonal lines. A scribe line 8 is a production line used when mass-producing semiconductor chips. Reference numeral 9 denotes a pulse laser spot, which is set slightly larger than the area of the integrated circuit forming area 7 of the semiconductor chip, as shown by surrounding the area with a broken line.

In this way, when the integrated circuit forming region 7 of the semiconductor chip and the laser spot region are aligned and the sample movement period and the pulse irradiation period of the pulse laser are synchronized and irradiation is performed, as shown in FIG. The peripheral edge of the laser spot region 11 is formed outside the semiconductor chip integrated circuit forming region 7 (shown by one side A), and the “twist” 10a of the Al layer 10 is formed outside the region of the semiconductor chip 7. In other words, “more” 10
The position where a is formed is above the scribe line 8,
This is an unnecessary part as a semiconductor chip.

In FIG. 2A, the area of the pulse laser spot 9 is set slightly larger than the area of one semiconductor chip 7, but as shown by the broken line in FIG. The area ′ may be set to be slightly larger than the area for four semiconductor chips 7. By doing so, irradiation can be performed with higher efficiency.

The substance to be buried in the via hole 2a may be pure Al or a compound of Al and another substance.

〔The invention's effect〕

According to the present invention, since the laser light is irradiated so that the peripheral end portion of the laser light irradiation region is located outside the region where the integrated circuit is formed in the semiconductor chip, the “twist” generated on the surface is integrated into the integrated circuit of the chip. It has the feature that it can be excluded from the formation area.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the method of the present invention, FIG. 2 is a diagram in which a semiconductor chip and a laser spot region are aligned with each other, FIG. 3 is a sectional view in which Al is deposited in a via hole, and FIG. 4 is Al. It is a figure which shows what is formed in a layer. In the figure, 1 is a Si substrate, 2 is an interlayer insulating film, 2a is a via hole, 3 and 10 are Al layers, 4 is a pulse laser beam, 7 is a semiconductor chip integrated circuit formation region, 8 is a scribe line, 9 and 9 ', Reference numeral 11 is a laser spot area, 10a is "strand", and A is one side of an integrated circuit formation area of a semiconductor chip.

Claims (1)

[Claims] 1. When the aluminum (3) formed on the via hole (2a) or a compound of aluminum and another substance is melted by a laser beam (4) to fill the via hole (2a), A semiconductor characterized by irradiating the laser light (4) so that the peripheral edge of the laser light (4) irradiation region (11) faces the outside of the region (7) in which the integrated circuit is formed in the semiconductor chip. Device manufacturing method.