KR20040101639A - injector for manufacturing semiconductor device - Google Patents

Abstract

PURPOSE: An injector for semiconductor fabrication is provided to reduce remarkably the contamination in an injector due to different gas materials mixed with each other and to improve the uniformity of a thin film by separating structurally different gas materials from each other. CONSTITUTION: An injector includes a plurality of gas inlet lines(222,224,226,228), a plurality of inner paths(152,154,156,158), and a plurality of nozzles(162,164,166,168). Each gas inlet line includes one end exposed to the outside through one surface of a chamber and the other end inserted into the chamber. Each inner path is connected with the other end of each gas inlet. Each nozzle is spaced apart from a wafer and connected with the inner path through a backside of an injector.

Description

Injector for semiconductor manufacturing

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly, to a chamber of an atomic layer deposition (ALD) process module for depositing a thin film on an upper surface of a wafer by an atomic layer deposition method. It is related to the injector (injector) installed in).

In recent years, with the development of science, the field of new materials, which enables the development and processing of new materials, has been rapidly developed, and the development results of these materials are driving the development of the semiconductor industry.

A semiconductor device is a large scale integration (LSI) that is realized through a process of depositing and patterning a plurality of thin films on a wafer, which is a substrate, and depositing such thin films. Semiconductor manufacturing processes, such as patterning, are typically performed in a process module that includes a chamber defining a closed reaction area within which a wafer is seated.

Each of the semiconductor manufacturing process modules has various forms according to a desired process, but as shown in FIG. 1, a chamber 20 defining a sealed reaction region in which a wafer is seated therein is commonly shown in FIG. 1. And a gas storage unit 40 for storing gaseous materials necessary for the semiconductor manufacturing process that is performed in the chamber 20.

The chamber 20 includes an inlet pipe 22 connected to the above-described gas storage device, a discharge pipe 24 for discharging the residual gaseous material therein, and a decompression means such as a pump P installed at an end thereof. Bar, first, after the wafer is introduced into the chamber 20 and closed, the pressure inside the chamber 20 is adjusted through a pressure-reducing means such as a pump P installed at the end of the discharge tube 24, and then the inflow pipe The wafer is processed through the chemical reaction of the gaseous material supplied into the chamber 20 through the 22.

On the other hand, as a method of depositing a thin film on the upper surface of a wafer through a chemical reaction of gaseous material, an atomic layer deposition method has been developed, which is abbreviated as ALD (ALD: Atomic Layer Deposition), which is a high purity thin film. In addition, the present invention is widely used in the semiconductor manufacturing process because it has the advantage of realizing a thin film having excellent uniformity and step coverage characteristics.

The atomic layer deposition method is similar to the general chemical vapor deposition method (CVD) in that a chemical reaction between two or more gaseous materials is used, but a general chemical vapor deposition method is generally used in a reaction zone where a wafer exists. Unlike the simultaneous inflow of multiple gaseous materials and the deposition of their reaction products onto the surface from above the wafer, there is a big difference in that the chemical reaction position between the gaseous materials is limited only to the wafer surface.

Therefore, a purge process is performed in which a plurality of source gases are sequentially introduced into the reaction zone in which the wafer to be deposited is located, and at the same time, the residual gaseous materials in the chamber are removed before and after each gaseous inflow step. As necessary, the gas storage unit 40 described above includes a first source gas storage unit 42 storing a first source gas, and a first purge gas storage unit 44 storing a first purge gas, respectively. And a second source material storage unit 46 for storing the second source gas and a second purge gas storage unit 48 for storing the second purge gas.

The source gases S1 and S2 and the purge gases P1 and P2 are alternately introduced into the chamber 20 in order to deposit a thin film having a very thin thickness on the upper surface of the wafer. It is repeated to deposit a thin film of the desired thickness.

At this time, each of the gas material is injected into the wafer in the chamber 20 can be divided into several ways, Figures 2 and 3 is a conceptual diagram for explaining a representative example, the part not related to the present invention Although briefly shown, it will be apparent that the injection of the gaseous material to the wafer, which will be described later, is performed in a chamber which is a closed reaction region.

First, FIG. 2 illustrates a gas injection method, which is generally called a shower head method. First, the wafer 1 is horizontally seated on the upper surface of the chuck 30 installed in the chamber, and then it is directly connected. It uses a method of injecting a gaseous material through the injector 26 installed on the top.

In this case, the first and second source gases S1 and S2 and the first and second purge gases P1 and P2 introduced into the chamber through the inlet pipe 22 are the same inlet pipe 22 and the injector, respectively. Injected sequentially via 26, in particular, the injector 26 is configured to inject a gaseous material from the top to the bottom of the wafer 1 in a state arranged in parallel with each other directly on top of the wafer (1). .

The showerhead method of spraying the gaseous material is generally one of the most widely used method, but after the first or the second source gas (S1 or S2) is injected as the gaseous material is diffused throughout the inside of the chamber, respectively Since there is a problem that a long time is required for the subsequent purge process, the prolongation of the process time is a fatal disadvantage in the low productivity atomic layer deposition method.

In addition, the inlet tube 22 and the injector 26 connected thereto are shared with each other to sequentially inject a plurality of gaseous substances, so that the respective purge processes are insufficient. Source gas may remain inside, and when other source gas is supplied into the chamber while the source gas used in the previous step remains, they eventually react in the gas phase to accumulate reaction products on the wafer. Since the chemical vapor deposition method is performed, it is difficult to obtain a thin film having excellent characteristics such as high purity to be implemented through the atomic layer deposition method.

In addition, as the gaseous substances are diffused in the entire interior of the chamber, frequent cleaning operations are required, thereby reducing the life of the process module.

3 illustrates a gas injection method commonly referred to as a laminar flow method, which first includes a buffer plate 50 arranged in parallel with the wafer 1 so that a gaseous material is disposed on the wafer. After defining the diffusion region so as to be concentrated on the surface, the first source gas S1, the first purge gas P1, and the second source are spaced between the buffer plate 50 and the wafer 1 on one side, respectively. The gas S2 and the second purge gas P2 are sequentially introduced.

The lamina flow method of spraying the gaseous material has the advantage of shortening the purge time and at the same time realizing a purer thin film, while the side of the gaseous material sprayed to cross the upper surface of the wafer 1 from the side. The gas material or the thin film adsorbed on the wafer 1 is easily desorbed due to the pressure, which has a problem in that the productivity is lowered.

In addition, such a lamina flow method also has the possibility of contamination of the thin film as the gas injection method of the showerhead method as the respective gaseous material is sequentially supplied through the same path.

The present invention has been made to solve the above problems, an object of the present invention is to provide an improved injector, which can implement a thin film of high purity by suppressing the reaction in the gas phase generated when each source material is introduced.

1 is a schematic structural diagram of a general AL process module

2 and 3 are each a conceptual diagram for explaining a gas injection method of a general ld process module

4 is a schematic cross-sectional view of an ADL process module mounted with an injector according to the present invention.

Figure 5 is a perspective view showing only the injector in accordance with the present invention

6 is a bottom view of the injector according to the invention.

<Description of the symbols for the main parts of the drawings>

100: chamber 120: chuck

150: injector 152, 154, 156, 158: euro

162, 164, 166, 168: nozzle 200: gas storage unit

222: first source gas inlet pipe 224: second source gas inlet pipe

226: third source gas inlet pipe 228: fourth source gas inlet pipe

232: first purge gas inlet pipe 234: second purge gas inlet pipe

236: third purge gas inlet pipe 238: fourth purge gas inlet pipe

In order to achieve the above object, the present invention is installed in a chamber having a reaction zone in which a wafer is seated therein, and is an injector for injecting gaseous material introduced from the outside into the wafer, and penetrates one surface of the chamber to the outside. A plurality of gas inlet pipes each having one end exposed to the other end and the other end inserted into the chamber; A plurality of internal passages formed on the inner surface of the injector so as to be distinguished from each other, and connected to the other ends of the plurality of inflow pipes, respectively; The present invention provides an injector including a plurality of nozzles connected to the respective flow paths, respectively, penetrating the bottom surface of the injector spaced apart from the wafer at a predetermined interval.

Particularly, the other ends of the plurality of gas inlet pipes are supplied with a purge gas and a different type of source gas, so that the selected one of the source gases and the purge gas can be alternately sprayed onto the wafer. Each of the plurality of concentric circles arranged on the same plane so as to gradually increase in diameter from the center, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

4 is a schematic cross-sectional view of an atomic layer deposition process module in which an injector 150 is installed that can be used to deposit a multi-component material according to the present invention. As an example, four source gases may be introduced into the chamber 100. State that can be shown. As shown, the atomic layer deposition process module of the present invention is a chamber 100 having a reaction region in which a wafer is seated therein, and a semiconductor manufacturing process proceeding in the chamber 100. It may be divided into a gas storage unit 200 for storing the required gaseous material.

In this case, the gas storage unit 200 may include a first source material storage unit 202, a second source material storage unit 204, and a third source material storage unit respectively storing different kinds of gaseous source materials. 204 and the fourth source material storage unit 208, and may include a first purge gas storage unit 212, a second purge gas storage unit 214, and a third purge gas storage unit which store an inert gas ( 216 and the fourth purge gas storage unit 218. The chamber 100 to which each of these gaseous substances is supplied includes a pressure reducing means such as a discharge pipe 124 for discharging residual gaseous substances therein and a pump P installed at an end thereof.

In addition, the chamber 100 is provided with a chuck 130 for supporting the wafer 1. The chamber 100 is provided with an injector 150 according to the present invention, and the respective gaseous substances introduced from the outside are provided. It is sprayed onto the wafer 1, which is characterized in that it is preferably a showerhead type injector 150 arranged in parallel on the top of the wafer 1. Although the present invention is not limited thereto, when the injector 150 is installed in a showerhead method, the diameter of the injector 150 may be approximately 1/3 to 1/2 of the diameter of the wafer 1, thereby facilitating purging. .

In this case, the upper end of the injector 1500 according to the present invention may include a first source gas inlet pipe 222 connected to the first source gas storage unit 202 and a second source gas storage unit 204, respectively. The second source gas inlet pipe 224 and the third source gas inlet pipe 226 connected to the third source gas storage part 206 and the fourth source gas inlet pipe connected to the fourth source gas storage part 208. 228 is installed independently. That is, one end of the first source gas inlet pipe to the fourth source gas inlet pipe (222, 224, 226, 228) is connected to each source gas storage unit (202, 204, 206, 208), the other end is independent The upper part of the injector 150 is connected to a predetermined area.

In particular, the first to fourth source gas inlet pipes 222, 224, 226, and 228 may be branched to the purge gas inlet pipes 232, 234, 236, and 238, respectively, in the vicinity of the injector 150. That is, as illustrated, the first purge gas inlet pipe 232 is provided in the first source gas inlet pipe 222, and the second purge gas inlet pipe 234 is provided in the second source gas inlet pipe 224. It can be seen that the third purge gas inlet pipe 236 is connected to the source gas inlet pipe 226, and the fourth purge gas inlet pipe 238 is connected to the fourth source gas inlet pipe 228.

As such, the other ends of the purge gas inlet pipes 232, 234, 236, and 238 connected to the source gas inlet pipes 222, 224, 226, and 228 corresponding to one end thereof are respectively purged gas storage units 212, 214, and 216. , 218).

After all, the configuration of the gas inlet pipe of the present invention is provided with the same number according to the type of gaseous material used in the semiconductor manufacturing process, unlike the common showerhead type injector share a single inlet pipe.

In addition, the first to fourth source gases introduced into the injector 1500 through the respective source gas inlet pipes 222, 224, 226, and 228 and the purge gas inlet pipes 232, 234, 236, and 238. (S1, S2, S3, S4) and the first to fourth purge gases (P1, P2, P3, 4) are respectively sequentially sprayed toward the internal wafer 1 of the chamber 100, wherein in the present invention It is characterized in that to give different independent injection paths to the gaseous material.

That is, referring to Figure 5 showing a partial plan view of the injector according to the present invention, and Figure 6, which is a bottom view thereof, the inner surface of the injector 150 according to the present invention each has a ring-shaped larger diameter from the center to the edge The first to fourth flow paths 152, 154, 156, and 158 are arranged concentrically and arranged on the same plane so as to have each of them. Each of the flow paths 152, 154, 156, and 158 is described above. The fourth source gas inlet pipes 222, 224, 226, and 228 are respectively inserted into the upper surface 150a of the injector, so that different gaseous substances are introduced.

In addition, the injector toward the wafer 1 at the lower end of the first to fourth source gas inlet pipes 222, 224, 226, and 228 inserted into the flow paths 152, 154, 156, and 158 as described above. A plurality of first to fourth nozzles 162, 164, 166, and 168 penetrating the bottom surface 150b of the bar are installed, whereby each gaseous material is introduced into and diffused through the chamber through different paths. .

In other words, the injector 150 according to the present invention is provided with a plurality of flow paths that are spatially separated from each other on its inner surface, and each of these flow paths are respectively exposed to the outside by a plurality of nozzles penetrating in the wafer direction. It includes a plurality of inlet pipes for supplying different gaseous material to each of these flow paths, so that the gaseous material introduced through each inlet pipe can be injected into the chamber with an independent movement path.

At this time, it is preferable that a plurality of flow paths are advantageously provided with three or more. Since three or more kinds of gaseous substances are used in a conventional atomic layer deposition process, they are separated from each other, and in particular, the type of purge gas used during the process. As shown in FIG. 2, the first to fourth flow paths 202, 204, 206, and 208 may be installed, and the number of these flow paths may be freely increased or decreased depending on the purpose. In particular, in the present invention, when a specific source is introduced through the first to fourth source gas inlet pipes (222, 224, 226, 228), the purge gas inlet pipe connected to the incoming source gas is turned off In addition, the purge gas inlet pipe connected to the remaining source gas inlet pipe except the incoming source gas may be adjusted to the on state to prevent contamination and the source may be brought into uniform contact with the upper surface of the wafer. It is especially preferable to make it easy to advance atomic layer adsorption.

As a result, in order for the plurality of flow paths 162, 164, 166, and 168 according to the present invention to be installed independently of each other on the inner surface of the injector 150, concentric circles arranged on the same plane so as to increase in diameter from the center to the edges. To maximize the spatial efficiency of each of the flow paths, the end of the source gas inlet pipe (222, 224, 226, 228) provided in the same number in each of the flow paths of the injector toward the wafer, respectively Since there are a plurality of nozzles 162, 164, 166, and 168 penetrating the bottom surface, several kinds of gaseous materials supplied from the gas storage unit 200 may be injected independently without mixing with each other.

Therefore, the mixing phenomenon between the source materials frequently observed in the general injector cannot be generated in the injector 150 according to the present invention.

4 to 6, the driving of the atomic layer deposition process module having the injector 150 according to the present invention described above is described with reference to FIGS. 4 to 6, when the wafer 1 is first introduced into the chamber 100 and then sealed. The pressure inside the chamber 100 is regulated through a decompression means such as a pump P installed at the end of the discharge pipe 124, and then, the first source is supplied through the first source gas inlet pipe 222 in a first step. The source material S1 is injected toward the wafer by the fourth nozzle 168 via the fourth flow path 158 of the injector 200. In this case, the purge gas (P2, P3, P4) through the remaining purge gas inlet pipes 234, 236, 238 except for the first purge gas inlet pipe 232 connected to one end of the first source gas inlet pipe (222). In order to prevent contamination of the interior of the chamber 100 and to allow the first source gas S1 to uniformly contact the upper surface of the wafer 1.

Thereafter, in the second step, the first purge gas P1 is identical to the first source gas S1 through the first purge gas inlet pipe 232 having one end connected to the first source gas inlet pipe 222. A first purge step is performed to remove the first source gas S1 that is injected into the chamber 100 via the fourth flow path 158 on the inner surface of the injector and the fourth nozzle 168 formed on the bottom surface of the injector. .

After that, the second source gas S2 via the second source gas inlet pipe 224, the second flow path 154 on the inner surface of the injector 150, and the second nozzle 164 on the bottom surface thereof, and the second source gas. The second purge gas inlet pipe 234, one end of which is connected to the inlet pipe 224, and the second purge gas P2 via the second flow path 154 and the second nozzle 164 enter the third source gas. The third source gas S3 and the third source gas inlet pipe 226 and one end thereof are connected to each other via the first flow path 152 and the first nozzle 162 formed in the injector 150 through the pipe 226. The third purge gas P3 is connected to the inlet pipe 228 and the fourth source via the first purge gas inlet pipe 236 via the first flow path 152 and the first nozzle 162. The fourth source gas S4 and the fourth purge gas inlet connected to one end of the fourth source gas inlet pipe 228 through the third flow path 156 and the third nozzle 166 formed on the injector 150. Pipe 238 and the third flow path 156 and the third The fourth purge gas P4 is sequentially supplied into the chamber 100 through the three nozzles 166 to constitute one cycle of the atomic layer deposition method.

In this case, when each source gas (S2, S3, S4) is introduced, as in the case where the first source gas (S1) is introduced, the remaining purge gas except for the purge gas inlet pipe connected to each source gas inlet pipe The purge gas can be supplied through the inlet pipe. For example, when the second source gas S2 is introduced, the first, third, and fourth purge gases P1, P3, and P4 are used, and when the third source gas S3 is introduced, the first and second are selected. When the fourth purge gas P1, P2, P4 and the fourth source S4 are introduced, the first, second, and fourth purge gases P1, P2, and P3 may be respectively introduced.

4 to 6 illustrate the case where four source gases S1, S2, S3, and S4 are introduced, this is merely an example, and an appropriate number of source gas inlet tubes and the same number of flow paths and nozzles may be used as necessary. It can be formed on the injector.

In addition, it will be apparent that the source gas inlet pipe and the position of the purge gas inlet pipe connected to the source gas inlet pipe may be arranged in other ways as needed, unlike those shown in the drawings. For example, the first source gas S1 and the first purge gas P1 pass through the center of the injector 150 so that the end of the first source gas inlet pipe 222 passes through the first flow path 152 and the first nozzle. It may be configured to be injected via 162.

That is, in the present invention, the injector 150 is divided into regions in which the source gas and the purge gas are sequentially provided in the next step to purge gas provided to remove the remaining source gas among the source gas and the introduced source gas. If the inner surface of the injector 150 can be configured to be introduced into the chamber 100 through an independent area of), the relative position of each gas inlet pipe, the flow path and the nozzle can be changed as necessary.

Through one cycle of the atomic layer deposition method of sequentially performing these steps, a very thin high purity thin film is deposited on the surface of the wafer 1, and then a thin film having a desired thickness is realized by repeating the same process.

The present invention provides an injector in which the atomic layer deposition method implemented through the atomic layer deposition process module separately injects different gaseous materials spatially.

Unlike the general case, the possibility of contamination generated by mixing different kinds of gaseous materials in the injector can be significantly reduced, and thus, an improved semiconductor manufacturing process can be realized.

In particular, the injector according to the present invention can be effectively distinguished even if a plurality of gaseous materials are introduced by providing a concentric shape that becomes wider with each flow path, and each gaseous material is sprayed onto the wafer through a nozzle which is a minute hole. It has the effect of improving the uniformity of the thin film.

Claims (3)

An injector which is installed in a chamber having a reaction region in which a wafer is seated therein and injects gaseous material introduced from the outside into the wafer, A plurality of gas inlet tubes each having one end exposed to the outside through the one surface of the chamber and the other end inserted into the chamber; A plurality of internal passages formed on the inner surface of the injector so as to be distinguished from each other, and connected to the other ends of the plurality of inflow pipes, respectively; A plurality of nozzles connected to the respective flow paths through the bottom surface of the injector corresponding to a predetermined distance from the wafer; Injector comprising. The method according to claim 1, The injector of the plurality of gas inlet pipes are respectively supplied with a purge gas and a different type of source gas, alternately spraying the selected one of the source gases and the purge gas to the wafer. The method according to claim 1, And the plurality of flow paths are a plurality of concentric circles arranged on the same plane such that each of the flow paths becomes larger in diameter from the center.