KR100773242B1 - Method of manufactruing semiconductor device - Google Patents

Abstract

A method of manufacturing a semiconductor device is provided to reduce a manufacturing error by removing a remaining film from an edge region around an active region before forming a silicide film on the active region. A semiconductor substrate includes an active region(AR) and an edge region(ER), which is arranged around the active region. A preliminary semiconductor device(60) is formed on the active region. A photoresist film is formed to cover the active region and expose the edge region. While the preliminary semiconductor device is formed by using the photoresist film as an etch mask, remaining films(23,39) are sequentially removed from the edge region. The photoresist film is removed from the active region. A silicide film is formed on the preliminary semiconductor device.

Description

Method of manufacturing a semiconductor device {METHOD OF MANUFACTRUING SEMICONDUCTOR DEVICE}

1 is a cross-sectional view illustrating a gate insulating film pattern and a polysilicon pattern formed on a semiconductor substrate.

FIG. 2 is a cross-sectional view illustrating the formation of low concentration source / drain around the gate shown in FIG. 1.

3 is a cross-sectional view illustrating a gate spacer formed on the gate illustrated in FIG. 2.

4 is a cross-sectional view illustrating the formation of a high concentration source / drain on the semiconductor substrate of FIG. 3.

FIG. 5 is a cross-sectional view illustrating a photoresist pattern covering the active region illustrated in FIG. 4.

FIG. 6 is a cross-sectional view of depositing a silicide metal on a semiconductor substrate after removing the residual film of the edge region illustrated in FIG. 5.

The present invention relates to a method for manufacturing a semiconductor device.

In recent years, with the development of technology of semiconductor devices, the performance of semiconductor devices has been rapidly improved. In particular, the MOS semiconductor device has been further miniaturized to improve the performance of the semiconductor device. As a result of this miniaturization, the gate length of the gate electrode, that is, the channel width is reduced, and the junction depth of the source / drain impurity diffusion region is shallow. ought. As a result, sheet resistances of the gate electrode and the source / drain are increased.

Recently, in order to reduce the resistance of the gate electrode and the source / drain due to the miniaturization of the semiconductor device, a salicide (SAL) is formed on the gate electrode and the source / drain to increase resistance of the gate electrode and the source / drain. It is preventing.

However, when the salicide is formed on the gate electrode and the source / drain after fabricating the semiconductor device, a fatal defect is frequently generated during the salicide process due to the residual film remaining at the edge of the wafer.

In order to realize the object of the present invention, the present invention removes the residual film remaining on the edge portion of the wafer after forming the salicide in the gate, source / drain of the semiconductor element after fabricating the semiconductor device, and then forming the salicide Provided is a method of manufacturing a semiconductor device that prevents process defects caused by a residual film during side processes.

A method of manufacturing a semiconductor device for realizing an object of the present invention includes forming a preliminary semiconductor device in an active region of a semiconductor substrate having an active region and an edge region disposed around the active region, the photoresist film covering the active region. Exposing the edge region by sequentially forming the photoresist film; and sequentially removing residual films remaining in the edge region during the formation of the preliminary semiconductor device by using the photoresist film as an etching mask, and the photoresist from the active region. Removing the film and forming a salicide in the preliminary semiconductor device.

Hereinafter, a method of manufacturing a semiconductor device in accordance with embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments, and has ordinary skill in the art. It will be apparent to those skilled in the art that the present invention may be embodied in various other forms without departing from the spirit of the invention.

1 to 6 are cross-sectional views illustrating a method of manufacturing a semiconductor device in accordance with an embodiment of the present invention.

1 is a cross-sectional view illustrating a gate insulating film pattern and a polysilicon pattern formed on a semiconductor substrate.

Referring to FIG. 1, a device isolation pattern is formed in an active region AR of the semiconductor substrate 10 having an active region AR and an edge region ER disposed around the active region AR. (5) is formed.

In order to form the device isolation pattern 5, a trench 3 is formed in the semiconductor substrate 10, and the device isolation pattern 5 is formed by filling an oxide in the trench 3.

After the device isolation pattern 5 is formed, a gate insulating film (not shown) is formed over the active area AR and the edge area ER of the semiconductor substrate 10 over the entire area. In this embodiment, the gate insulating film may be formed by oxidizing the semiconductor substrate 10.

After the gate insulating layer is formed, a polysilicon layer (not shown) covering the gate insulating layer is formed on the active region AR and the edge region ER of the semiconductor substrate 10.

After the polysilicon layer is formed on the gate insulating film, a photoresist film is disposed over the entire surface of the polysilicon layer, the photoresist film is patterned by an exposure process and a developing process, and a photoresist pattern is disposed on the polysilicon layer.

After the photoresist pattern is disposed on the polysilicon layer, the polysilicon layer and the gate insulating layer are patterned by using the photoresist pattern as an etching mask, so that the gate 20 is formed on the active region AR of the semiconductor substrate 10. do.

On the other hand, in the edge region ER of the semiconductor substrate 10, the remaining films 23 which are part of the gate oxide film and the polysilicon layer remain.

FIG. 2 is a cross-sectional view illustrating the formation of low concentration source / drain around the gate shown in FIG. 1.

2, impurities are implanted into the semiconductor substrate 10 using the gate 30 as an ion implantation mask, and a low concentration source 32 and a low concentration drain 34 are formed around the gate 30.

3 is a cross-sectional view illustrating a gate spacer formed on the gate illustrated in FIG. 2.

Referring to FIG. 3, after the low concentration source 32 and the low concentration drain 34 are formed on the semiconductor substrate 10, an insulating film (not shown) covering the gate 30 is formed on the semiconductor substrate 10. In this embodiment, the insulating film may be a nitride film SiNx. Alternatively, the insulating film may be an oxide film SiO2. Alternatively, the insulating film may have a structure in which an oxide film and a nitride film are alternately arranged.

The nitride film covering the gate 30 is formed on the semiconductor substrate 10.

The nitride film covering the gate 30 is etched back etched, and as a result, a gate spacer 38 is formed on the side surface of the gate 30.

On the other hand, the remaining film 39 which is a part of the nitride film is formed again in the edge region ER of the semiconductor substrate 10.

4 is a cross-sectional view illustrating the formation of a high concentration source / drain on the semiconductor substrate of FIG. 3.

Referring to FIG. 4, impurities are implanted at high concentration into the semiconductor substrate 10 using the gate spacer 38 as an ion implantation mask to form a high concentration source 33 and a high concentration drain 35 on the semiconductor substrate 10. As a result, a preliminary semiconductor element 60 in which salicide is not formed on the semiconductor substrate 10 is manufactured. Thereafter, salicide may be formed in the preliminary semiconductor device 60.

FIG. 5 is a cross-sectional view illustrating a photoresist pattern covering the active region illustrated in FIG. 4.

Referring to FIG. 5, in the present embodiment, the remaining film 39 disposed in the edge region ER of the semiconductor substrate 10 before the salicide is formed in the preliminary semiconductor element 60 formed on the semiconductor substrate 10. 23) Remove them first. In this case, if the remaining films 39 and 23 are not removed, defects may occur during the process of forming the salicide in the preliminary semiconductor device 60.

To this end, in the present embodiment, the active region AR in which the preliminary semiconductor elements 60 are formed is covered with the photoresist pattern 70 to expose the edge region ER of the semiconductor substrate 10.

Thereafter, the nitride film, which is the remaining film 39 disposed in the edge region ER of the semiconductor substrate 10, is first removed through a wet or dry etching process.

After the nitride film, which is the residual film 39 disposed on the edge region ER, is first removed, the residual film 23 including the polysilicon layer and the gate oxide film disposed under the nitride film is removed again through a wet or dry etching process. Complete removal from ER).

FIG. 6 is a cross-sectional view illustrating that a silicide metal is deposited on a semiconductor substrate after removing the residual film of the edge region illustrated in FIG. 5.

Referring to FIG. 6, a silicide metal, for example, a tungsten film, a titanium film, or a nickel film is deposited on the active region AR and the edge region ER of the semiconductor substrate 10, and then heat treated to form a high concentration source 33. The silicide 100 is formed on the top surfaces of the gate structure 20 and the high concentration drain 35, respectively.

On the other hand, since the silicide metal disposed on the upper surface of the edge region ER does not react with silicon, no silicide is formed in the edge region ER. Subsequently, the silicide metal on which silicide is not formed is removed from the semiconductor substrate 10 to manufacture the semiconductor device 110.

As described in detail above, the active region after removing the remaining film remaining in the edge region disposed around the active region before silicide is formed during the formation of the preliminary semiconductor element in which no silicide is formed in the active region of the semiconductor substrate is formed. It is effective to prevent the defect caused by the residual film during the formation of the silicide by forming the silicide in.

Although the detailed description of the present invention has been described with reference to the embodiments of the present invention, those skilled in the art or those skilled in the art will have the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that various modifications and variations can be made in the present invention without departing from the scope of the art.

Claims (4)

Forming a preliminary semiconductor element in an active region of a semiconductor substrate having an active region and an edge region disposed around the active region; Forming a photoresist film covering the active region to expose the edge region; Sequentially removing residual films remaining in the edge region while forming the preliminary semiconductor device using the photoresist film as an etching mask; Removing the photoresist film from the active region; And Forming a salicide in the preliminary semiconductor device. The method of claim 1, wherein forming the preliminary semiconductor device Forming a gate structure having a gate oxide pattern and a polysilicon pattern on the gate oxide pattern in the active region; Forming a low concentration source / drain in the active region using the gate structure as an ion implantation mask; Forming a gate spacer on sidewalls of the gate structure; And Forming a high concentration source / drain in the active region by using the gate spacer as an ion implantation mask. The method of claim 1, wherein the remaining films include an oxide film, a polysilicon film, and a nitride film. The method of claim 3, wherein the remaining films are sequentially etched.

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