JPS6018933A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the area of a programmable element for a semiconductor memory storage, and to minimize the area of a semiconductor chip by coating a wiring for cutting by fusing with an insulating film and forming a metallic film surrounding a cutting section for the wiring for cutting by fusing on the insulating film. CONSTITUTION:A programmable element is formed to a semiconductor substrate, and a first insulating film is formed on the element. A wiring 1 for cutting connected to an active region in the programmable element is shaped by polycrystalline Si, a second insulating film is formed on the wiring, and windows are bored and the wiring and the second insulating film are connected by an Al wiring 2 and a contact section 3. A metallic film 5 is formed on the second insulating film so as to surround at least cutting section for the wiring 1. A window is bored previously to the cutting section. When the wiring 1 is irradiated by laser beams, laser beams projected to the film 5 are reflected by the film 5, and polycrystalline Si shaped to the lower section of the film 5 is not affected. Consequently, a margin l2 between the wiring 1 and a region 4 can be reduced extremely. Accordingly, the area of the programmable element can be minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device, and more particularly, to a semiconductor device including a 10-gram element of a semiconductor memory device having 10% redundant bits.

In recent years, semiconductor memory devices have rapidly increased in mass VCC. However, as the memory capacity per chip increases, it is becoming increasingly difficult to maintain manufacturing yields above a practical level, and redundant configuration technology is being adopted to increase yield by setting redundant bits. Programmable cables used in redundant configuration technology are broadly divided into those that use fuses and those that completely fuse the wiring using a laser.

A programmable element used in the conventional redundancy loss technique will be described with reference to the drawings. FIG. 1 is a flat-tm diagram of an example of a conventional seven-log programmable element.

A program element is formed on the semiconductor substrate lfi, and the program element is covered with a first insulating film. On top of this, a fusing wiring l made of polycrystalline silicon is provided that continues at the active region rC of the program element. A continuous aluminum wiring 2 is provided. 4 is a diffusion region.

The wire 1 for fusing is cut by heating rainbow polycrystalline silicon using a laser source. However, if the laser beam is irradiated onto the transistor gate rC, polycrystalline silicon, diffusion region, etc., these things will be damaged and cause leakage, etc. The space between
r: A margin t1 as shown in FIG. 1 was required.

This margin t1 is determined by the positioning accuracy when irradiating the laser beam.

For the above reasons! Semiconductor chips containing programmable cables that were intended to be fused with the Niji Laser 9 had the disadvantage of being large in area. Also, what is the alignment accuracy of VC laser irradiation to reduce the area? The higher the value, the more expensive the equipment becomes.
The drawback was that throughput decreased.

The present invention eliminates all of the above-mentioned drawbacks, reduces the margin, reduces the area of the programmable cable of the semiconductor memory device, and therefore provides a semiconductor device with a reduced semiconductor chip area. The semiconductor device includes a program element having a circular shape 5y on a round outer substrate, and an active region of the program element ( It is configured to include a land-connected fusing wiring, a second insulating film covering the fusing wiring, and a metal film surrounding at least the fusing portion of the fusing wiring on the second insulating film.

[Embodiments of the present invention will be described with reference to the drawings.

Figure 2 shows the present invention's Issho 7II! 191 is a plan view of FIG.

A program element sound is formed on a semiconductor substrate, and a first insulating film is formed thereon. The active region i'v of the program element is formed of a polycrystalline glue l for intermittent fusing, and a second insulating film is provided thereon. A window is opened and the aluminum wiring 2 and the contact part 3 are connected to each other. In this embodiment, a metal film 5 is provided on the second insulating layer so as to at least surround the fusing portion of the fusing wiring l. Aluminum in metal film 5? When used, it surrounds the melt 8 which has the advantage of being formed at the same time as the aluminum wiring 3.
= On IIc of tt, the metal film 5 is not entirely formed. i.e. window 6
fj: Leave 6 digits.

When the polycrystalline silicon fusing wiring ii is thermally irradiated with a laser beam, the laser beam irradiates not only the fusing wiring 1 but also its surroundings, but the laser beam that irradiates the metal film 5 is reflected by the metal film 5, Do not affect the polycrystalline silicon used for the lower part of the metal film 5 (the diffusion region provided or the gate electrode, etc.). Polycrystalline silicon absorbs laser light extremely easily, so it is easy to melt and melt the metal. This is because the film reflects most of the laser light, so even if the laser light is irradiated with enough energy to melt all of the polycrystalline silicon, the metal film 5 will not be damaged. The margin 12u between the wiring 1 and the diffusion region 4 can be made very small.Also, there is no need for an expensive device with high alignment accuracy of the laser beam, and the throughput can also be increased.

As explained in detail above, according to the present invention, - it is possible to reduce the area of the programmable element of the semiconductor memory device, and thus to obtain a semiconductor device with a reduced area of the semiconductor chip; The effect is great.

[Brief explanation of drawings]

FIG. 1 is a plan view of an example of a conventional programmable cord, and FIG. 2 is a plan view of an embodiment of the present invention. l... Wiring for fusing, 2... Aluminum wiring, 3.
...Contact part, 4...Diffusion region, End...Metal film,
6...window.

Claims (1)

[Claims] A round semiconductor substrate, a grogram element, a fusing wiring connected to an active region cB of the program element formed of a polycrystalline semiconductor upstream of a first insulating film provided on the semiconductor substrate, and the fusing wiring. and a metal film surrounding at least the fusing wire of the fusing wiring on the second insulating film.