KR101044005B1 - Method for manufacturing capacitor of semiconductor device - Google Patents

Abstract

In the method for manufacturing a capacitor of a semiconductor device according to the present invention, forming a mold insulating film having a hole on a semiconductor substrate, and forming a conductive film and a gap-fill induction film for a storage node on the hole surface and the mold insulating film. Forming a gap-fill film to fill the hole on the gap-fill inducing film, removing the gap-fill film and the gap-fill inducing film until the mold insulating film is exposed; Forming a storage node by removing the remaining gap-fill film and the mold insulating layer; and forming a dielectric layer and a plate node on the storage node.

Description

METHODS FOR MANUFACTURING CAPACITOR OF SEMICONDUCTOR DEVICE

1A to 1E are cross-sectional views illustrating processes of manufacturing a capacitor of a semiconductor device according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100 semiconductor substrate 102 buffer film

104: etching stop film 106: mold insulating film

108: storage node contact plug 110: metal film for the storage node

112: gap-fill film 114: gap-fill film

116: dielectric film 118: plate node

120: Capacitor H: hole for storage node plug contact

The present invention relates to a method of manufacturing a capacitor of a semiconductor device, and more particularly, to a method of manufacturing a capacitor of a semiconductor device capable of manufacturing a capacitor having a stable structure by preventing loss of a storage node.

As the demand for semiconductor memory devices has soared, various techniques for obtaining high capacity capacitors have been proposed. Here, the capacitor has a structure in which a dielectric film is interposed between the storage node and the plate node, and the capacitance thereof is proportional to the electrode surface area and the dielectric constant of the dielectric film, and the distance between the electrodes, that is, It is inversely proportional to the thickness of the dielectric film.

Therefore, in order to obtain a high capacity capacitor, it is required to use a dielectric film having a large dielectric constant, to enlarge the electrode surface area, or to reduce the distance between the electrodes. However, reducing the distance between the electrodes, that is, the thickness of the dielectric film has its limitation, and researches for forming a capacitor having a high capacity have been conducted by using a dielectric film having a high dielectric constant or increasing the electrode surface area.

In this case, the method for increasing the electrode surface area is typically a method of forming the shape of the storage node into a concave or cylinder-shaped three-dimensional structure, and among these, the cylindrical storage node has a concave shape. The relatively large electrode area compared to the storage node is advantageous for high integration devices.

Hereinafter, a manufacturing method of a semiconductor device including a process of forming a cylindrical storage node according to the related art will be briefly described.

First, an interlayer insulating film is deposited on a semiconductor substrate having a predetermined lower structure to cover the lower structure, and then the contact insulating layer is formed by etching the interlayer insulating film. Then, a polysilicon film is deposited to fill the contact hole, and then the polysilicon film is etched back to expose the interlayer insulating film to form a storage node contact.

Subsequently, an etch stop layer and a mold insulating layer are sequentially deposited on the interlayer insulating layer including the storage node contact, and then the mold insulating layer and the etch stop layer are etched to form holes for the storage node exposing the storage node contacts. Subsequently, after depositing a conductive film on the entire surface of the substrate including the hole for the storage node, the conductive film is etched back to form a cylindrical storage node so as to be separated between storage nodes.

Next, a dip-out process is performed to remove the mold insulating layer serving as the storage node forming frame, and then a dielectric layer and a plate node are sequentially formed on the storage node to form a capacitor. do. Subsequently, a series of subsequent known processes are sequentially performed on the substrate product on which the capacitor is formed to complete the semiconductor device.

On the other hand, with the advancement of semiconductor technology and the high speed and high integration of semiconductor devices, the demand for miniaturization of patterns and high precision of pattern dimensions is increasing. Thus, in order to secure the capacity of a desired capacitor, The height of the should be as high as possible.

However, in the above-described prior art, an insulation process for the storage node is performed using a barrier film made of a material such as an oxide film to prevent the storage node from falling down during the deep-out process. If the oxide layer is not completely gap-filled in the space, the barrier layer formed of the oxide layer formed on the upper portion of the hole during the etch-back process of the storage node is lost, and the storage node under the hole is exposed, so that the solution used in the etch-back process. You will be attacked by.

Therefore, when the storage node is attacked by the etch solution of the etch-back process as described above, the thickness of the storage node is locally reduced or a pin-hole is generated and subsequent dip-out process is performed. As the chemical used to penetrate into the loss portion, the bunker defect caused by the loss of the insulating layer under the storage node and the failure of the device due to the disconnection of the wiring is caused.

In addition, if the storage node is lost and its thickness is less than a predetermined thickness as described above, it cannot easily serve as an electrode during the operation of the device, thereby increasing the leakage current of the capacitor to generate a bit fail. It reduces the yield and reliability of the device, leading to poor device operation.

The present invention provides a method of manufacturing a capacitor of a semiconductor device capable of preventing a storage node attack and preventing a device failure due to a bunker defect and a disconnection of wiring.

In addition, the present invention provides a method of manufacturing a capacitor of a semiconductor device capable of reducing the leakage current of the capacitor to prevent the occurrence of bit fail.

In addition, the present invention provides a method of manufacturing a capacitor of a semiconductor device capable of improving the yield and reliability of the device, thereby preventing the failure of the device operation.

A method of manufacturing a capacitor of a semiconductor device according to the present invention includes forming a mold insulating film having a hole on a semiconductor substrate; Forming a conductive film and a gap-fill induction film for a storage node on the hole surface and the mold insulating film; Forming a gap-fill film to fill the hole on the gap-fill induction film; Removing the gap-fill film and the gap-fill induction film until the mold insulating film is exposed; Forming a storage node by removing the gap-fill film and the mold insulating film remaining in the hole; And forming a dielectric layer and a plate node on the storage node.

The mold insulating layer is formed of at least one of PSG, BPSG, PE-TEOS, O ₃ USG, and HDP.

The storage node is formed of any one of W, WN, TiN, Si, and Ru.

The gap-fill induction film is formed of a nitride film.

The gap-fill induction film is formed in a furnace or chamber type reactor.

The gap-fill induction film is formed to a thickness of 1 ~ 300Å.

The gap-fill induction film is formed to a thickness of 1 to 50 microns.

The gap-fill film is formed of any one of O ₃ USG, PE-TEOS, and Si USG.

The gap-fill induction film and the gap-fill film are performed in-situ.

The dielectric layer is formed of at least one of Al2O3, HfO2, ZrO2, TiO2, Ta2O5, BST, and PZT.

The plate node is formed of at least one of TiN, WN, WN / W and Ru.

(Example)

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

According to the present invention, after forming a storage node on a mold insulating film having a hole for storage node contact, a silicon nitride film is formed on the storage node, and an oxide film is formed to fill the storage node contact hole on the silicon nitride film. .

In this case, when the oxide film is formed on the silicon nitride film by the silicon nitride film, as the incubation time of the oxide film becomes longer, the oxide film may be deposited to a uniform thickness up to and below the hole for the storage node contact. By performing an etch-back process for insulation of the storage node in a state completely gap-filled with the oxide film in a space inside a storage node contact hole, the attack of the storage node by the etchant of the etch-back process is prevented. can do.

Therefore, the loss due to the attack of the storage node can be prevented as described above, and the failure of the device due to the breaker of the bunker defect and the wiring due to the loss of the insulating film under the storage node is fundamentally prevented. You can prevent it.

In addition, since the loss due to the attack of the storage node can be prevented as described above, it is possible to increase the leakage current of the capacitor due to the decrease of the thickness of the storage node and to prevent the occurrence of bit fail. Improper device operation can be prevented by improving device yield and reliability.

1A to 1E are cross-sectional views illustrating processes of manufacturing a capacitor of a semiconductor device according to an exemplary embodiment of the present invention.

Referring to FIG. 1A, a buffer layer 102, an etch stop layer 104, and a mold insulating layer 106 are formed on a semiconductor substrate 100 on which a storage node contact plug 108 is formed to cover the storage node contact plug 108. ) In turn.

Preferably, the buffer film 102 and the etch stop film 104 are formed of an oxide film and a nitride film, and the mold insulating film 106 is any one of PSG, BPSG, PE-TEOS, O ₃ USG, and HDP. It is formed of at least two laminated films.

Referring to FIG. 1B, the mold insulating layer 106, the etch stop layer 104, and the buffer layer 102 are etched to form a storage node contact hole H. Referring to FIG. Then, the storage node metal film 110 is deposited on the mold insulating layer 106 including the storage node contact hole H surface to form a storage node. The metal layer 110 forming the storage node is preferably formed of any one of W, WN, TiN, Si, and Ru.

Referring to FIG. 1C, a gap-fill induction film 112 is formed on a mold insulating layer 106 including a surface of the storage node contact hole H on which the storage node is formed, and the gap-fill induction film 112 is formed. A gap-fill film 114 is formed to fill the storage node contact hole H thereon.

Here, the gap-fill induction film 112 is formed of a silicon nitride film within a range of 300 mW, preferably within a range of 50 mW, and formed in a furnace or a furnace type reactor.

The gap-fill film 114 is formed of any one of O ₃ USG, PE-TEOS, and Si USG, wherein the gap-fill induction film 112 and the gap-fill film 114 are in-situ. It is preferable to perform (In-Situ) or In-Chamber.

Here, the silicon nitride film as the gap-fill induction film 112 may increase the incubation time of the gap-fill film 114 to uniformly cover the gap between the upper and lower portions of the hole H for the storage node contact. -The film 114 can be formed, which causes the oxide film to be completely gap-filled in the space inside the hole for the storage node contact during a subsequent etch-back process for isolation of the storage node. The attack of the storage node by the etchant of the etch-back process may be prevented.

Referring to FIG. 1D, the gap-fill film 114 and the gap-fill induction film 112 are removed by etch-back or CMP until the mold insulation film 106 is exposed.

Referring to FIG. 1E, the gap-fill film 114 and the gap-fill induction film 112 in the storage node contact hole H are first removed before the dip-out process for the mold insulating film, and then, The mold insulating layer 106 is removed by dip-out until the etch stop layer 104 is exposed.

Subsequently, the dielectric layer 116 and the plate node 118 are formed on the deep-out and remaining storage node surfaces to complete the capacitor 120 of the semiconductor device according to the exemplary embodiment.

The dielectric layer 116 is formed of any one of Al2O3, HfO2, ZrO2, TiO2, Ta2O5, BST, and PZT or at least two or more laminated films, and the plate node 118 is formed of TiN, WN, WN / W, and Ru. It is formed of any one film or at least two or more laminated films.

Here, the storage node may prevent the attack by the gap-fill film 114 and the gap-fill induction film 112 in the storage node contact hole H during the deep-out process.

As described above, according to the present invention, when the oxide film is formed on the silicon nitride film, the oxide film is formed to have a uniform thickness to the upper and lower portions of the storage node contact hole as the incubation time of the oxide film is increased by the silicon nitride film. It can be gap-filled, preventing attack of the storage node by an etchant in an etch-back process of the storage node.

Therefore, the failure of the device due to the bunker defect and the disconnection of the wiring due to the loss of the insulating layer under the storage node can be prevented, and the capacitor of the capacitor according to the decrease of the thickness of the storage node can be prevented. Since the leakage current can be increased and the occurrence of bit fail can be prevented, it is possible to improve the yield and reliability of the device, thereby preventing the failure of the device operation.

In the above-described embodiments of the present invention, the present invention has been described and described with reference to specific embodiments, but the present invention is not limited thereto, and the scope of the following claims is not limited to the scope of the present invention. It will be readily apparent to those skilled in the art that the present invention may be variously modified and modified.

As described above, in the manufacture of a capacitor of a semiconductor device, after forming a storage node on a mold insulating film having a storage node contact hole, the silicon nitride film and the storage node contact hole are buried on the storage node. The oxide layer may be formed so that the oxide layer may be gap-filled by the silicon nitride layer to a uniform thickness to the upper and lower portions of the storage node contact hole. You can prevent it.

Therefore, since the present invention can prevent the loss due to the attack of the storage node as described above, the failure of the device due to the bunker defect and disconnection of the wiring due to the loss of the insulating film under the storage node It is possible to prevent the source, and to increase the leakage current of the capacitor due to the reduction of the thickness of the storage node and thereby prevent the occurrence of bit fail.

Therefore, the present invention can improve the yield and the reliability of the device to prevent the failure of the device operation.

Claims (11)

Forming a mold insulating film having holes on the semiconductor substrate; Forming a conductive film for a storage node on the hole surface and the mold insulating film; Forming a gap-fill induction film on the conductive film for the storage node in a furnace or a chamber type reactor; Forming a gap-fill film to fill the hole on the gap-fill induction film; Removing the gap-fill film and the gap-fill induction film until the mold insulating film is exposed; Completely removing the gap-fill film and the gap-fill induction film remaining in the hole; Removing the mold insulating layer to form a storage node; And Forming a dielectric layer and a plate node on the storage node; Capacitor manufacturing method of a semiconductor device comprising a. The method of claim 1, The mold insulating film is a capacitor manufacturing method of a semiconductor device, characterized in that formed by at least one film of PSG, BPSG, PE-TEOS, O ₃ USG and HDP. The method of claim 1, The storage node is a capacitor manufacturing method of a semiconductor device, characterized in that formed by any one of the film of W, WN, TiN, Si and Ru. The method of claim 1, And the gap-fill induction film is formed of a nitride film. delete The method of claim 1, The gap-fill induction film is a capacitor manufacturing method of the semiconductor device, characterized in that formed in the thickness of 1 ~ 300Å. The method of claim 6, The gap-fill induction film is a capacitor manufacturing method of a semiconductor device, characterized in that formed in a thickness of 1 ~ 50Å. The method of claim 1, The gap-fill film is a capacitor manufacturing method of a semiconductor device, characterized in that formed of any one of the film O ₃ USG, PE-TEOS and Si USG. The method of claim 1, The gap-fill induction film and the gap-fill film is a capacitor manufacturing method of the semiconductor device, characterized in that performed in-situ (In-Situ). The method of claim 1, The dielectric layer is formed of at least one of Al2O3, HfO2, ZrO2, TiO2, Ta2O5, BST and PZT. The method of claim 1, The plate node is formed of at least one film of TiN, WN, WN / W and Ru of the capacitor manufacturing method of the semiconductor device.

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