JPH02133956A - Nonfusible memory device - Google Patents

Abstract

PURPOSE:To obtain a high yield by forming an amorphous Si film between metal electrode wiring parts. CONSTITUTION:Metal wiring parts 3, 3' composed of Al or the like are formed, via an SiO2 film, on the surface of an Si substrate 1 where a semiconductor device has been formed; amorphous Si 4 is formed, by using a plasma CVD method or the like, at a gap of about 0.1mum between said metal wiring parts 3, 3'. Since a minimum of the amorphous Si 4 is enough at the gap between the metal wiring parts 3, 3', the amorphous Si 4 may be formed so as to be stretched to the surface of the metal wiring parts 3, 3'; in addition, a film of the amorphous Si 4 may be formed on the whole surface including the surface of the metal wiring parts 3, 3'. Thereby, a nonfusible memory part composed of amorphous Si can be formed after a metal wiring part has been formed; a nonfusible part is not alloyed by an excess heat treatment before a write operation; an ON state is not caused by a state that the part is fused and cut; thereby it is possible to enhance a yield of a nonfusible semiconductor device.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to the structure of a non-fusing semiconductor memory device.

[Conventional technology]

Conventionally, non-fusible semiconductor memory devices have a laminated structure in which an amorphous Si film is formed on a first metal electrode wiring, and a second metal wiring is further formed on top of the amorphous Si film with the amorphous Si film sandwiched therebetween. There was a storage device.

[Problem to be solved by the invention]

However, according to the above-mentioned conventional technology, there is a problem in that the amorphous Si film is alloyed with the metal wiring in advance, and what should initially be an off state becomes an on state.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and provide a non-fuseable semiconductor memory device structure that can achieve high yield.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention relates to a non-fuseable memory device, and takes means to form an amorphous Si film between metal electrode wirings.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 1 is a sectional view of a main part of a non-fuseable semiconductor memory device showing one embodiment of the present invention. That is, the surface of the St substrate 1 on which the semiconductor device is formed is coated with Sin and Ag via the film.
A metal wiring 3.3' is formed, and the metal wiring 3.
．． Amorphous S is placed between the gap of about 0.1 μm at 3′.
i4 is formed by plasma CVD method or the like. The minimum amount of amorphous Si4 is required between the gaps between the metal wirings 3.3', and the amorphous S14 may be formed extending to the surface of the metal wirings 3.3', as shown in this example figure.
The amorphous S14 film may be formed over the entire surface including the surface of the metal wiring 3.3'.

The reason why the film of amorphous S14 may be formed over the entire surface is that the non-fuse memory area is determined by the gap between the metal wirings 3 and 3', and the gap between the film and other metal wirings on the film 2 is To use an example as a reference, for a storage gap of 0.1 μm, a gap of 0.3 μm or more is sufficient, since amorphous Si only functions as an insulator. The material of the metal wiring 3.3' is not limited to AfI, and may be WET i N5Cu or Doped Po
Needless to say, it may be made of 1ySi or the like, or may be a combination of different metals, or may have a multilayer structure or a structure in which a bathoya metal is formed in the storage portion.

FIG. 2 is a plan view of essential parts of a non-fuseable storage device showing another embodiment of the present invention. In other words, the gap between the metal wirings 13 and 13' is formed by providing a convex portion on at least one of the metal wirings, bringing them together, and forming an amorphous 5i14 film on the surface to fill the gap. , a convex portion is formed on the electrode for the purpose of ensuring discharge in the gap portion.

FIG. 3 is a plan view of essential parts of a non-fuseable storage device showing another embodiment of the present invention. That is, metal wiring 23.23
' gap parts are formed in parallel, and amorphous Si 24 is formed on the surface of the gap part to fill the gap.The length of the gap part, which is a non-fusing memory part, is lengthened and voltage is applied. This structure was formed in order to increase the probability that the molten amorphous Si melts, thereby realizing a reliable on state.

〔Effect of the invention〕

According to the present invention, a non-fusible memory region made of amorphous Si can be formed after metal wiring, and the occurrence of an on state due to alloying or melting of the non-fusible region before writing due to extra heat treatment is eliminated, and the non-fusible memory region is formed after metal wiring. This has the effect of increasing the yield of storage devices.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of a non-fuseable semiconductor memory device showing an embodiment of the present invention. FIGS. 2 and 3 are layout plan views of main parts of a non-fuse semiconductor memory device showing another embodiment of the present invention. Figure 1 1 ・ ・ −・ ・ ・ ・ 2 ・ ・ ・ ・ ・ ・ 3.3', 13. 4.14.24 - Si substrate/Sin, film 1B', 23.23' - Metal wiring pot amorphous Si Above Figure 2 Applicant Seiko Epson Co., Ltd. Agent Patent attorney Masayoshi Kamiyanagi (and 1 other person) No. Figure 3

Claims (1)

[Claims] A non-fusing memory device characterized by forming an amorphous S_i film between metal electrode wirings.