KR20080088315A - Method of manufacturing semiconductor device - Google Patents

Abstract

A method for manufacturing a semiconductor device is provided to increase the effective surface area of a reservoir capacitor by recessing a reservoir capacitor forming region and then growing a silicon column. A reservoir capacitor forming region of a semiconductor substrate(100) is recessed. A metal layer is formed on a lower surface of the recessed substrate. A first thermal treatment is performed on the resultant substrate on which the metal layer is formed to transform the metal layer into a metal particle(106). A second thermal treatment is performed on the resultant substrate transformed from the metal layer into the metal particle to grow a silicon column(108) from a substrate part being contacted to the metal particle to a direction perpendicular to the substrate. The recessing process of the reservoir capacitor region of the semiconductor substrate is performed by using a poly silicon layer as a hard mask layer.

Description

Manufacturing method of semiconductor device {METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE}

1A to 1D are cross-sectional views illustrating processes for manufacturing a semiconductor device in accordance with an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100 semiconductor substrate 102 hard mask film

104: metal film 106: metal particles

108: silicon rod

The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a method for manufacturing a semiconductor device capable of increasing the capacitance of a storage capacitor.

Recently, as the integration of memory products is accelerated due to the development of semiconductor manufacturing technology, the unit cell area is greatly reduced, and the operating voltage is reduced. As a result, problems such as shortening the refresh time of the device and a soft error occur, and in order to prevent such a problem, a capacitor having a high capacity and low leakage current is prevented. Development is constantly required.

As is well known, the capacitance of the capacitor is proportional to the surface area of the electrode and the dielectric constant of the dielectric and inversely proportional to the thickness of the dielectric film corresponding to the distance between the electrodes. Therefore, in order to secure the desired capacitor capacity, the height of the capacitor should be increased as much as possible to secure the maximum surface area of the electrode, and a dielectric film having a large dielectric constant should be used and the thickness thereof should be made thin.

Hereinafter, a manufacturing method of a semiconductor device including a process of forming a capacitor according to the prior art will be briefly described.

First, a PSG (Phosphours Silicate Glass) film and a Plasma Enhanced-Tetra Ethyl Ortho Silicate (PE-TEOS) layer are formed on a semiconductor substrate including a predetermined structure including a device isolation layer, a bit line, and a storage node contact plug defining an active region. The cap oxide film is deposited as a laminated film of the film.

The cap oxide layer is then etched to form holes for the storage node exposing the storage node contact plug. In this case, the hole for the storage node should be formed to a high enough height to secure the capacity of the capacitor. Subsequently, a barrier film and a conductive film are deposited in the holes for the storage node, and then etched back to form a storage node.

Subsequently, a dielectric film and a plate node are formed on the storage node to form a capacitor, and then a series of known subsequent processes are sequentially performed to complete a semiconductor device according to an exemplary embodiment of the present invention.

Meanwhile, a method of inserting an accumulator capacitor to filter a sudden change in power supply voltage level (High Frequency) in order to stabilize a power supply when manufacturing a highly integrated semiconductor device has been proposed. That is, the accumulation capacitor prevents generation of noise due to switching in digital logic.

In addition, since the accumulation capacitor can remove high frequency noise that enters power, or directly draw and use power required by the device at high frequency, the accumulation capacitor eliminates inductance components when the external capacitor is connected to external power. This results in an effect of lowering the impedance seen in the power stage. Therefore, it is desirable to insert as much accumulation capacitors as possible for high frequency operation and stable power supply of highly integrated semiconductor devices.

Such accumulator capacitors have been using flat capacitors, but later, recess type capacitors, which can increase the area of the capacitor, have been applied to increase the electric capacity.

However, the recessed capacitor is a structure in which a two-dimensional structure of a conventional flat plate capacitor is converted to a three-dimensional structure, but depends on the current level of technology of lithography, and the area of the capacitor is increased. Since it is inevitable to rely on the Top Down method, there is a limit in that the accumulation capacitor cannot be made in a complicated and detailed shape, and thus, the capacity of the desired accumulation capacitor cannot be sufficiently secured.

The present invention provides a method of manufacturing a semiconductor device that can effectively increase the capacity (Capacitance) of the storage capacitor for stabilizing the power supply when manufacturing a highly integrated semiconductor device.

The method of manufacturing a semiconductor device according to the present invention is a method of manufacturing a semiconductor device in which a storage capacitor is formed in a peripheral circuit area in order to stabilize power supply of the semiconductor device, and recesses the storage capacitor formation area of the semiconductor substrate. Doing; Forming a metal film on a bottom surface of the recessed substrate portion; Converting the metal film into metal particles by first heat treating a substrate product on which the metal film is formed; And growing a silicon rod in a direction perpendicular to the substrate from a portion of the substrate contacted with the metal particles by performing a second heat treatment on the substrate resultant of the metal film converted into metal particles.

Here, the step of recessing the accumulation capacitor formation region of the semiconductor substrate is performed using a polysilicon film as a hard mask film.

Forming a metal film on a bottom surface of the recessed substrate portion may include forming a mask pattern exposing the recessed substrate portion; Forming a metal film on a portion of the substrate exposed by the mask pattern; And removing the mask pattern.

The metal film is formed of any one of Au film, Ni film and Ni Silicide film.

The metal film is formed to a thickness of 50 to 1000 GPa.

The first heat treatment for converting the metal film into metal particles is performed at a temperature of 700 to 900 ° C.

The growing of the silicon rod is performed in a silicon-containing gas atmosphere.

The silicon containing gas is a SiCl ₄ gas.

After growing the silicon rod, removing metal particles on the silicon rod; And forming an accumulation capacitor in the portion of the substrate where the silicon rod is grown.

In addition, the method of manufacturing a semiconductor device according to the present invention is a method of manufacturing a semiconductor device in which a storage capacitor is formed in a peripheral circuit area to stabilize power supply of the semiconductor device. Recessing; Forming a metal film on a bottom surface of the recessed substrate portion; Converting the metal film into metal particles by first heat treating a substrate product on which the metal film is formed; And growing a ZnO rod in a direction perpendicular to the substrate from a portion of the substrate contacted with the metal particles by performing a second heat treatment on the substrate product in which the metal film is converted into metal particles in a Zn-containing gas atmosphere.

The step of recessing the accumulation capacitor formation region of the semiconductor substrate is performed using a polysilicon film as a hard mask film.

Forming a metal film on a bottom surface of the recessed substrate portion may include forming a mask pattern exposing the recessed substrate portion; Forming a metal film on a portion of the substrate exposed by the mask pattern; And removing the mask pattern.

The metal film is formed of any one of Au film, Ni film and Ni Silicide film.

The metal film is formed to a thickness of 50 to 1000 GPa.

The first heat treatment for converting the metal film into metal particles is performed at a temperature of 700 to 900 ° C.

After growing the ZnO rod, removing metal particles on the ZnO rod; And forming an accumulation capacitor in the portion of the substrate where the ZnO rod is grown.

(Example)

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

SUMMARY OF THE INVENTION The present invention is a method of manufacturing a semiconductor device in which a storage capacitor is formed in a peripheral circuit area to stabilize power supply of the semiconductor device. The present invention provides a recess type in a peripheral circuit area when a recess gate of the semiconductor substrate is formed. When forming accumulation capacitors together in a recess type, a silicon metal is grown using catalytic metal on the recessed substrate surface.

In this way, by growing a silicon rod on the substrate portion, the effective surface area of the storage capacitor can be wider than in the related art, thereby increasing the capacity of the storage capacitor, thereby increasing the capacity required for the highly integrated semiconductor device. Can be secured.

1A to 1D are cross-sectional views of processes for describing a method of manufacturing a semiconductor device according to an embodiment of the present invention.

Referring to FIG. 1A, a hard mask layer partitioned into a cell region (not shown) and a peripheral circuit region and exposing the accumulation capacitor formation region on a semiconductor substrate 100 having an accumulation capacitor formation region in the peripheral circuit region ( 102). The hard mask layer 102 is formed of a polysilicon layer.

Then, the portion of the substrate 100 exposed by the hard mask layer 102 is etched to recess the accumulation capacitor formation region. In this case, the etching is performed by a dry etching method.

Referring to FIG. 1B, a mask pattern (not shown) exposing a portion of the recessed substrate 100 is formed on the entire surface of the substrate 100 including the recessed portion. The mask pattern is formed of a photosensitive film. Subsequently, the metal film 104 is formed on the bottom surface of the recessed substrate 100 exposed by the mask pattern.

Then, the mask pattern is removed. In this case, when the mask pattern is removed, the metal film portion formed on the remaining portion except for the recessed substrate 100 may be removed together.

Here, the metal film 104 is formed to serve as a catalyst during the growth of the subsequent silicon rod, and is formed to a thickness of about 50 to 1000 kW using any one of Au film, Ni film and Ni Silicide film.

Referring to FIG. 1C, the resultant substrate 100 on which the metal film is formed is first heat treated in a temperature atmosphere of about 700 to 900 ° C. to convert the metal film into metal particles 106.

In this case, the size of the metal particle 106 is determined according to the thickness of the metal film, the temperature and time at the time of the first heat treatment, and the atmosphere in the process chamber in which the first heat treatment is performed, and the factors are appropriately controlled. Control can yield the desired diameter of the subsequent silicon rods.

Referring to FIG. 1D, a second heat treatment of a resultant of the substrate 100 converted into the metal particles 106 may be perpendicular to the substrate 100 from a portion of the substrate 100 that is in contact with the metal particles 106. The silicon rods 108 of the Nano size are grown in the direction. The silicon rod 108 has a diameter proportional to the size of the metal particle 106.

Here, during the second heat treatment for growing the silicon rod 108, it is preferable to make the inside of the process chamber into a silicon-containing gas, for example, a SiCl ₄ gas atmosphere.

In addition, during the second heat treatment, the inside of the process chamber may be made into a Zn-containing gas atmosphere instead of the silicon-containing gas atmosphere. In this case, the substrate is in contact with the metal particles 106 instead of the silicon rod 108. From the (100) portion, nano-sized ZnO rods are grown in a direction perpendicular to the substrate 100.

Subsequently, although not shown, metal particles on the silicon rods are removed, the accumulation capacitors are formed in the accumulation capacitor formation region including the surface of the silicon rods, and subsequently, a series of well-known subsequent steps are sequentially performed to carry out the present invention. The semiconductor device according to the example is completed.

Here, the present invention forms an accumulation capacitor formed in the peripheral circuit region to stabilize the power supply of the semiconductor device in the portion of the substrate where the nano-sized silicon rods are grown, thereby reducing the effective surface area of the accumulation capacitor. You can widen it.

Accordingly, the present invention can effectively increase the capacitance of the accumulation capacitor by widening the effective surface area of the accumulation capacitor, thereby securing sufficient capacity required for the highly integrated semiconductor device.

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 can increase the effective surface area of the storage capacitor by growing a silicon rod after recessing the storage capacitor formation region.

In addition, the present invention can increase the capacity of the storage capacitor by increasing the effective surface area of the storage capacitor, thereby ensuring a sufficient capacity required for the highly integrated semiconductor device.

Claims (16)

A semiconductor device manufacturing method for forming a storage capacitor in the peripheral circuit region to stabilize the power supply of the semiconductor device, Recessing an accumulation capacitor formation region of the semiconductor substrate; Forming a metal film on a bottom surface of the recessed substrate portion; Converting the metal film into metal particles by first heat treating a substrate product on which the metal film is formed; And Second heat treating a substrate resultant of which the metal film is converted into metal particles to grow a silicon rod in a direction perpendicular to the substrate from a portion of the substrate in contact with the metal particles; Method of manufacturing a semiconductor device comprising a. The method of claim 1, Recessing the accumulation capacitor formation region of the semiconductor substrate, A method of manufacturing a semiconductor device, comprising using a polysilicon film as a hard mask film. The method of claim 1, Forming a metal film on the bottom of the recessed substrate portion, Forming a mask pattern exposing the recessed substrate portion; Forming a metal film on a portion of the substrate exposed by the mask pattern; And Removing the mask pattern; Method of manufacturing a semiconductor device comprising a. The method of claim 1, The metal film is a semiconductor device manufacturing method, characterized in that formed of any one of the Au film, Ni film and Ni Silicide film. The method of claim 1, The metal film is formed in a thickness of 50 to 1000 GPa. The method of claim 1, The first heat treatment for converting the metal film into metal particles is performed at a temperature of 700 ~ 900 ℃. The method of claim 1, Growing the silicon rod, A method for manufacturing a semiconductor device, characterized in that carried out in a silicon-containing gas atmosphere. The method of claim 7, wherein The silicon-containing gas is a method of manufacturing a semiconductor device, characterized in that the SiCl ₄ gas. The method of claim 1, After growing the silicon rod, Removing metal particles on the silicon rods; And Forming an accumulation capacitor in a portion of the substrate where the silicon rod is grown; Method of manufacturing a semiconductor device further comprising. A semiconductor device manufacturing method for forming a storage capacitor in the peripheral circuit region to stabilize the power supply of the semiconductor device, Recessing an accumulation capacitor formation region of the semiconductor substrate; Forming a metal film on a bottom surface of the recessed substrate portion; Converting the metal film into metal particles by first heat treating a substrate product on which the metal film is formed; And A second heat treatment of the substrate resultant of the metal film converted into metal particles in a Zn-containing gas atmosphere to grow a ZnO rod in a direction perpendicular to the substrate from a portion of the substrate contacted with the metal particles; Method of manufacturing a semiconductor device comprising a. The method of claim 10, Recessing the accumulation capacitor formation region of the semiconductor substrate, A method of manufacturing a semiconductor device, comprising using a polysilicon film as a hard mask film. The method of claim 10, Forming a metal film on the bottom of the recessed substrate portion, Forming a mask pattern exposing the recessed substrate portion; Forming a metal film on a portion of the substrate exposed by the mask pattern; And Removing the mask pattern; Method of manufacturing a semiconductor device comprising a. The method of claim 10, The metal film is a semiconductor device manufacturing method, characterized in that formed of any one of the Au film, Ni film and Ni Silicide film. The method of claim 10, The metal film is formed in a thickness of 50 to 1000 GPa. The method of claim 10, The first heat treatment for converting the metal film into metal particles is performed at a temperature of 700 ~ 900 ℃. The method of claim 10, After growing the ZnO rod, Removing metal particles on the ZnO rods; And Forming an accumulation capacitor in the portion of the substrate where the ZnO rod is grown; Method of manufacturing a semiconductor device further comprising.

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