KR20080028543A - Fuse box of semiconductor device and method for forming the same - Google Patents

Abstract

A fuse box of a semiconductor device and a method for forming the same are provided to prevent generation of cracks due to exposure of a TiN layer in a blowing process by forming selectively a fuse including a TiN pattern only at a contact part of a contact plug. A lower structure is formed on a semiconductor substrate(31). A first interlayer dielectric(32) is formed on the semiconductor substrate to cover the lower structure. A fuse(35) is formed on the first interlayer dielectric. A second interlayer dielectric(36) is formed on the first interlayer dielectric including a fuse. A contact plug(37) comes in contact with the fuse within the second and first interlayer dielectrics. A metal line(38) comes in contact with the contact plug on the second interlayer dielectric. A stacked layer of a TiN layer and a polysilicon layer(34) is formed selectively at a contact region between the fuse and the contact plug.

Description

Fuse box of semiconductor device and method for forming thereof {FUSE BOX OF SEMICONDUCTOR DEVICE AND METHOD FOR FORMING THE SAME}

1 is a cross-sectional view for explaining a fuse box of a semiconductor device according to the prior art.

Figure 2 is a photograph of a semiconductor device showing a conventional problem.

3 is a cross-sectional view illustrating a fuse box of a semiconductor device in accordance with an embodiment of the present invention.

4A through 4E are cross-sectional views illustrating processes of a fuse box of a semiconductor device in accordance with an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

31 semiconductor substrate 32 first interlayer insulating film

33: TiN film 33a: TiN pattern

34 polysilicon film 35 fuse

36: second interlayer insulating film 37: contact plug

38 metal wiring 39 insulating film

40: protective film

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuse box of a semiconductor device and a method of forming the same, and more particularly, to a fuse box and a method of forming a semiconductor device capable of preventing a failure of an adjacent fuse caused by a crack.

A semiconductor device mainly includes a fabrication (FAB) process of repeatedly forming a circuit pattern set on a silicon substrate to form cells having an integrated circuit, and packaging the substrate on which the cells are formed in a chip unit (Chip). Packaging and assembly process. In addition, a process for inspecting electrical characteristics of cells formed on the substrate is performed between the fabrication process and the assembly process.

The inspection step is a step of determining whether the cells formed on the substrate have an electrically good state or a bad state. This is to reduce the effort and cost consumed in the assembly process by removing the cells having a bad state through the inspection process before performing the assembly process. In order to detect the cells having the defective state at an early stage and regenerate them through a repair process.

Here, the repair process will be described in more detail as follows.

Redundancy cells are added to replace defective devices or circuits in the design of devices for the purpose of improving the manufacturing yield of devices in the event of a defect in the semiconductor device manufacturing process, and connecting the redundant cells to the integrated circuit. In order to design a fuse together, the repair process is a process in which a cell, which has been found to be defective through an inspection process, is connected to a spare cell embedded in a chip using the fuse to be regenerated. That is, location information of cells to be repaired is generated by performing a fuse blowing process of cutting a specific one of the fuses using a laser.

Meanwhile, the fuse has been formed of a polycrystalline polysilicon film. However, as the thickness of the polysilicon film becomes thin, a contact plug formed to contact the fuse is caused to penetrate through the fuse. Thus, conventionally, a method of forming a stacked structure of a TiN film and a polysilicon film has been used.

Hereinafter, a fuse box of a semiconductor device including a fuse having a stacked structure of a conventional TiN film and a polysilicon film will be described with reference to FIG. 1.

Referring to FIG. 1, a conventional fuse box includes a first interlayer insulating layer 12 formed in a fuse region of a semiconductor substrate 11, a fuse 15 formed on the first interlayer insulating layer 12, and the fuse 15. A second interlayer insulating film 16 formed on the first interlayer insulating film 12 so as to cover the contact hole, a contact plug 17 and a second contact hole formed in contact with both sides of the fuse 15 in the second interlayer insulating film 16. The metal wiring 18 is formed on the interlayer insulating film 16 to be in contact with the contact plug 17.

Here, the fuse 15 is formed of a laminated film structure of the TiN film 13 and the polysilicon film 14, and the insulating film 19 and the protective film 20 are sequentially formed on the second interlayer insulating film 16. . In the protective film 20, the insulating film 19, and the one-thick second interlayer insulating film 16 of the fuse region, a repair trench in which the second interlayer insulating film 16 having a predetermined thickness is left on the fuse 15. (T) is formed.

Then, although not shown, a known reliability evaluation and repair process including a fuse blowing process of cutting a specific one of the fuses using a laser is sequentially performed.

Here, the TiN film and the polysilicon film of the fuse blown during the blowing process are exposed to the air. In the subsequent reliability evaluation performed after the blowing process, the TiN film of the blown fuse is oxidized and moisture penetrates through the cut place. This increases.

However, in the above-described prior art, there is a problem in that the volume of the oxidized TiN film is expanded, so that cracks, in which gaps are formed at the interface between the first and second interlayer insulating films, are generated as shown in FIG. 2.

In addition, as the crack continues to the non-blowed adjacent fuse, the TiN film of the adjacent fuse is oxidized, so that the resistance of the non-blowed adjacent fuse increases, causing a fail that is incorrectly recognized as if blown.

Accordingly, an object of the present invention is to provide a fuse box of a semiconductor device and a method of forming the same, which are devised to solve the conventional problems as described above, which can prevent the occurrence of cracks caused by the blowing process and the reliability evaluation. There is this.

Another object of the present invention is to provide a fuse box of a semiconductor device and a method of forming the same, which can prevent a failure of an adjacent fuse caused by a crack by preventing the occurrence of the crack.

The fuse box of the semiconductor device of the present invention for achieving the above object, a semiconductor substrate formed with a lower structure; A first interlayer insulating film formed on the semiconductor substrate to cover a lower structure; A fuse formed on the first interlayer insulating film; A second interlayer insulating film formed on the first interlayer insulating film including the fuse; A contact plug formed in contact with the fuse in the second and first interlayer insulating films; And a metal wiring formed on the second interlayer insulating film to be in contact with the contact plug, wherein the fuse has a laminated film structure of a TiN film and a polysilicon film selectively in a region in contact with the contact plug. In the remaining area, the polysilicon film is made of a single film structure.

In addition, the fuse box forming method of the semiconductor device of the present invention for achieving the above object comprises the steps of: forming a first interlayer insulating film on a semiconductor substrate formed with a lower structure; Depositing a TiN film on the first interlayer insulating film; Etching the TiN film to form a TiN pattern; Forming a polysilicon film on the first interlayer insulating film including the TiN pattern; Patterning the polysilicon film to cover the TiN pattern to form a fuse having a laminated film structure of the TiN film and the polysilicon film; Forming a second interlayer insulating film on the first interlayer insulating film including the fuse; Forming a contact plug in the second and first interlayer insulating layers to be in contact with the fuse; And forming a metal wiring on the second interlayer insulating film to be in contact with the contact plug, wherein the contact plug is formed on the second interlayer insulating film portion in the region where the TiN film pattern is formed.

Here, the forming of the TiN pattern may include forming a polysilicon layer on the TiN film; Forming a mask pattern on the polysilicon layer, the mask pattern covering a contact plug region; Selectively removing the polysilicon layer and the TiN film portion exposed by the mask pattern; And removing the mask pattern.

(Example)

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, the technical principle of the present invention will be briefly described. The present invention has a laminated film structure of a TiN film and a polysilicon film in a portion contacting with a contact plug on the first interlayer insulating film, A fuse having a single film structure of the polysilicon film is formed.

In this case, since the TiN film is formed only on the fuse part contacting the contact plug and the TiN film is not formed on the remaining fuse part to be blown, a crack caused by oxidation of the TiN film even when moisture penetrates into the blown fuse part during subsequent reliability evaluation. It is possible to prevent the occurrence of, through which, it is possible to prevent the failure of the adjacent fuse caused by the crack.

In detail, the fuse box of the semiconductor device according to the embodiment of the present invention will be described with reference to FIG. 3.

Referring to FIG. 3, the fuse box of the present invention may include a semiconductor substrate 31 having a lower structure (not shown), a first interlayer insulating layer 32 formed to cover the lower structure on the semiconductor substrate 31, and the A fuse 35 formed on the first interlayer insulating film 33, a second interlayer insulating film 36 formed on the first interlayer insulating film 32 including the fuse 35, and the second and first interlayer insulating films 36. And a contact plug 37 formed in contact with the fuse 35 in the 32, and a metal wiring 38 formed in contact with the contact plug 37 on the second interlayer insulating layer 36.

The insulating film 39 and the protective film 40 are sequentially formed on the second interlayer insulating film 36 including the metal wiring 38. In the protective film 40, the insulating film 39, and the one-thick second interlayer insulating film 36 in the fuse region, a repair trench in which the second interlayer insulating film 36 having a predetermined thickness is left on the fuse 35 is formed. (T) is formed.

In addition, the fuse 35 has a laminated film structure of the TiN pattern 33a and the polysilicon film 34 selectively only in the region in contact with the contact plug 37, and the polysilicon film 34 in the remaining region. It consists of a single membrane structure.

Here, the present invention forms a fuse 35 made of a laminated film of the TiN pattern 33a and the polysilicon film 34 only at the portion contacted with the contact plug 37 to form a contact resistance of the fuse 35. , By forming a fuse 35 formed of a single layer of the polysilicon layer 34 in the remaining portion including the scheduled blowing region, it is possible to prevent the occurrence of cracks caused by oxidation of the TiN layer during the subsequent reliability evaluation, Failure of adjacent fuses can be prevented.

4A to 4E are cross-sectional views illustrating processes for forming a fuse box of a semiconductor device according to an exemplary embodiment of the present invention.

Referring to FIG. 4A, a first interlayer insulating layer 32 is formed on a fuse region of a semiconductor substrate 31 on which a predetermined lower structure (not shown) is formed to cover the lower structure. Next, a TiN film 33 is deposited on the first interlayer insulating film 32.

Referring to FIG. 4B, a thin polysilicon layer (not shown) is formed on the TiN layer 33 to a thickness of about 1/10 of the thickness of the polysilicon layer to be subsequently deposited, and then a contact plug is formed on the polysilicon layer. A mask pattern (not shown) covering a predetermined area is formed. Here, the polysilicon layer is formed as an anti-reflection film during the photo process for forming a subsequent TiN film pattern.

Subsequently, the polysilicon layer and the TiN film portion exposed by the mask pattern are selectively removed to form the TiN pattern 33a, and then the mask pattern is removed.

Referring to FIG. 4C, a polysilicon layer 34 is deposited on the first interlayer insulating layer 32 including the TiN pattern 33a to cover the TiN pattern 33a. Next, the polysilicon layer 34 and the TiN pattern 33a are patterned to form a fuse 35 on the first interlayer insulating layer 32.

Here, the fuse 35 is formed of a laminated film structure of the TiN pattern 33a and the polysilicon film 34 in a region in contact with a contact plug for forming a contact resistance, but in the remaining region including a region to be blown, the poly The silicon film 34 has a single film structure. Therefore, in the present invention, since the TiN film is not exposed to air during the subsequent blowing process, oxidation of the TiN film can be prevented, and thus generation of cracks can be prevented.

Referring to FIG. 4D, a second interlayer insulating film 36 is formed on the first interlayer insulating film 32 including the fuse 35 to cover the fuse 35, and then the second interlayer insulating film 36 is formed. And the polysilicon film 34 are etched to form contact holes.

Subsequently, a metal film is deposited to fill the contact hole, and then CMP is formed to form a contact plug 37 contacting the fuse 35. In this case, the contact plug 37 may be formed in a portion of the second interlayer insulating film 36 in the region where the TiN film pattern 33a is formed to form a contact resistance of the fuse 35.

Referring to FIG. 4E, after the metal interconnection 38 is formed on the second interlayer dielectric layer 36 to be in contact with the contact plug 37, the second interlayer dielectric layer 36 including the metal interconnection 38 is formed on the second interlayer dielectric layer 36. An insulating film 39 for insulating between metal lines is formed on the passivation layer, and then a protective film 40 is formed on the insulating film 39.

Subsequently, the protective film 40, the insulating film 39, and the one-thick second interlayer insulating film 36 in the fuse region are etched to repair the second interlayer insulating film 36 having a predetermined thickness on the fuse 35. The trench T is formed.

Then, although not shown, a known reliability evaluation and repair process including a fuse blowing process of cutting a specific one of the fuses using a laser is sequentially performed.

In the present invention, a fuse formed of a laminated film of a TiN film and a polysilicon film is formed at a portion contacting the contact plug, and a fuse formed of a single film of a polysilicon film is formed at the remaining portion, thereby preventing the TiN film from being exposed during the blowing process. . Therefore, the present invention can prevent the occurrence of cracks due to the exposure of the TiN film, thereby preventing the failure of the adjacent fuse caused by the cracks.

As mentioned above, although the present invention has been illustrated and described with reference to specific embodiments, the present invention is not limited thereto, and the following claims are not limited to the scope of the present invention without departing from the spirit and scope of the present invention. It can be easily understood by those skilled in the art that can be modified and modified.

As described above, the present invention by forming a fuse containing a TiN pattern selectively to only the portion in contact with the contact plug, it is possible to prevent the crack caused by the exposure of the TiN film during the subsequent blowing process, through this, due to the fuse It is possible to prevent the occurrence of adjacent fuses.

Claims (3)

A semiconductor substrate having a lower structure formed thereon; A first interlayer insulating film formed on the semiconductor substrate to cover a lower structure; A fuse formed on the first interlayer insulating film; A second interlayer insulating film formed on the first interlayer insulating film including the fuse; A contact plug formed in contact with the fuse in the second and first interlayer insulating films; And In the fuse box of the semiconductor device comprising a; metal wiring formed in contact with the contact plug on the second interlayer insulating film, The fuse has a laminated structure of a TiN film and a polysilicon film selectively in the region in contact with the contact plug, and the fuse box of the semiconductor device, characterized in that the single layer structure of the polysilicon film in the remaining areas. Forming a first interlayer insulating film on a semiconductor substrate on which a lower structure is formed; Depositing a TiN film on the first interlayer insulating film; Etching the TiN film to form a TiN pattern; Forming a polysilicon film on the first interlayer insulating film including the TiN pattern; Patterning the polysilicon film to cover the TiN pattern to form a fuse having a laminated film structure of the TiN film and the polysilicon film; Forming a second interlayer insulating film on the first interlayer insulating film including the fuse; Forming a contact plug in the second and first interlayer insulating layers to be in contact with the fuse; And And forming a metal wiring on the second interlayer insulating layer to be in contact with the contact plug. And forming the contact plug in the second interlayer insulating film portion of the region where the TiN film pattern is formed. The method of claim 2, Forming the TiN pattern, Forming a polysilicon layer on the TiN film; Forming a mask pattern on the polysilicon layer, the mask pattern covering a contact plug region; Selectively removing the polysilicon layer and the TiN film portion exposed by the mask pattern; And Removing the mask pattern; A fuse box forming method of a semiconductor device comprising a.

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