KR20030080574A - chamber for semiconductor device manufacturing - Google Patents

Abstract

PURPOSE: A chamber for manufacturing a semiconductor device is provided to be capable of minimizing the heat-shock supplied to a wafer and forming an improved thin film at the wafer by using a heating wire. CONSTITUTION: A chamber for manufacturing a semiconductor device is provided with a sealed reaction region(112) for loading a wafer(5) and an inlet pipe(114) installed at the upper portion of the chamber for supplying many kinds of gases from the outside to the reaction region. At this time, the chamber further includes a plurality of heating wires(152a) capable of generating heat, arrayed between the inlet pipe and the wafer. Preferably, each heating wire generates the heat of 1000-2000 °C. Preferably, the heating wire made of metal, is electrically connected to a power supply part.

Description

Chamber for semiconductor device manufacturing

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly, to a semiconductor manufacturing thin film defining a sealed reaction area in which a wafer is seated therein and depositing a chemical reaction product of the gaseous material introduced therein as a thin film on the wafer. A chamber is a vapor deposition apparatus.

A semiconductor device is a large scale integration (LSI) circuit which is realized through a plurality of deposition and patterning processes of a thin film on a wafer, which is a substrate. It may be listed as an epitaxy process, a thin film deposition process, a diffusion / ion implantation process, a photo-lithography, an etching process, and the like.

Among them, the thin film deposition process is inevitably required for each component of the semiconductor device, and thus, a very important process is repeated several times throughout the entire manufacturing process of the semiconductor device. Oxide film (SiO ₂ ) mainly used for gate oxide film and field oxide film, nitride film (Si ₃ N ₄ ) used as a mask or device protection layer for insulation or diffusion / ion implantation between conductive layers, and as a gate electrode instead of metal The polysilicon film (poly-Si), the metal film of the electrode role to connect the components or connect the external terminals in the semiconductor device can be largely classified into four types.

In addition, as a method of depositing these thin films, chemical vapor deposition (CVD), which is excellent in uniformity, step coverage and excellent productivity, is widely used. By simultaneously injecting multiple reactants into the zone, chemical reaction products generated between these gases are stacked and deposited on the wafer surface.

These thin film deposition processes are generally carried out in a thin film deposition apparatus called a chamber (chamber), Figure 1 is a schematic cross-sectional view.

The chamber is a hermetically sealed reaction vessel defining a reaction zone 12 enclosed therein. The chamber is an inlet pipe 14 through which external gaseous material is introduced, a discharge pipe 16 through which gaseous material is discharged, and an end thereof. In the reaction region 12, a wafer table for supporting the wafer 5, for example, the susceptor 20 is provided. Accordingly, after the wafer 5 is seated on the upper surface of the susceptor 20 in the chamber 10 and the chamber 10 is sealed, the reaction region 12 is appropriately decompressed through the pump P and the discharge pipe 16. Subsequently, chemical reactions of gaseous substances introduced into the reaction zone 12 through the inlet pipe 14 are induced to deposit reaction products on the wafer 5 surface.

In this case, in order to induce an easy chemical reaction between gaseous substances, a heater 22 capable of generating heat is mounted in the susceptor 20. The heater 22 generally uses a resistance heating method that generates heat by electric power. In order to drive the chamber 10, the chamber 10 includes a power supply 24.

On the other hand, depending on the type of thin film implemented in the chamber 10, a high temperature of 700 ° C. or higher may be formed in the reaction region, and when the thin film is a semiconductor nitride film (Si ₃ N ₄ ) or an oxide film (SiO ₂ ), At least one gaseous material among NH ₃ , N ₂ O, and O ₂ may be used as the first gas S ₁ introduced therein, and one selected from SiH ₄ and Si ₂ H ₆ may be used as the second gas S ₂ . In particular, since NH ₃ , N ₂ O, O _2, etc. maintain a very stable state, a high temperature of 700 ° C. or higher is required to break the bond between these molecules.

However, in such a high temperature process, the wafer 5, which is a thin film deposition target, is also exposed to high temperature for a long time, and thus receives a severe thermal shock. As a result, the state of the previously deposited thin film is deformed, or the doping state of the ion impurity is changed. Various problems will arise. In addition, the high temperature process has a disadvantage in that the configuration of the device is complicated, and the high temperature control is difficult, so that it is difficult to expect a smooth thin film deposition process, which in turn causes a great threat to the reliability of the completed semiconductor device.

In the past, efforts to lower the process temperature of thin film deposition have been continuously performed. For example, the first and / or second gases S ₁ and S ₂ are excited by plasma before being introduced into the chamber 10. A remote plasma method that flows into the reaction zone 12 has been developed. To this end, a plasma generating apparatus of capacitively coupled plasma (CCP) or inductively coupled plasma (ICP) is mounted on A and / or B of FIG. 1.

However, the thin film deposition method using the remote plasma also shows some problems, such as sputtering phenomenon or plasma charging damage of the wafer 5 by plasma ions.

Plasma in the form of partially charged ions has very difficult characteristics to control, and sputtering phenomenon in which plasma ions collide with the wafer 5 at high speed causes severe physical damage to the wafer 5, In particular, if the plasma density in the reaction region 12 is uneven or excessively high, plasma charging damage or the like may occur, in which the silicon oxide film (gate insulating film) previously deposited on the wafer 5 is severely damaged. This is especially true as the patterning trend of the semiconductor device increases.

In addition, as the remote plasma generator is additionally provided in the existing chamber 10, the construction cost of the apparatus is increased, as well as the first and second flows into the chamber 10 for the excitation and maintenance of the gaseous material into the plasma. / Or the pressure of the second gas (S ₁ , S ₂ ) is bound to be limited, there is a problem that the productivity is lowered.

In addition, by installing a heating device in the region A and / or B of Figure 1, a pre-heating method for preheating the gas passing through the high temperature and then introduced into the chamber 10 has been introduced, In addition, the supply pressure of the gaseous material to the chamber 10 is bounded to have a significant impact on productivity, and the increase in manufacturing cost for the construction of the device and the phenomenon that the heated gaseous material cools again before reaching the chamber 10 are caused. Frequently, the results are not satisfactory.

As a result, in the thin film deposition process for the manufacture of semiconductor devices, efforts to lower the process temperature have been continuously made and some methods have been proposed, but until now, minimizing productivity or impact on the wafer 5 or inexpensive device configuration The way to satisfy the cost, etc. has not been developed.

The present invention has been made to solve the above problems, it is possible to implement a more improved thin film while minimizing the thermal shock applied to the wafer, and in particular, the cost of the device for its configuration, while the productivity is more improved It is an object of the present invention to provide a thin film deposition chamber.

1 is a schematic cross-sectional view of a typical semiconductor manufacturing chamber.

2 is a schematic cross-sectional view of a chamber for manufacturing a semiconductor according to the present invention.

3A to 3B are respectively an internal perspective view of a chamber for manufacturing a semiconductor equipped with a heating unit according to an example of the present invention;

Figure 4 is a perspective view showing only the heating unit in accordance with the present invention

<Description of Symbols for Main Parts of Drawings>

5: wafer 110: chamber

112: reaction zone 116: discharge pipe

120: susceptor 150a: heating unit

151a: frame 152a: heating wire

In order to achieve the above object, the present invention defines an enclosed reaction region in which a wafer is seated therein, and includes an inlet tube for supplying a plurality of gaseous substances from the outside to the reaction region, and thus, generated in the reaction region. A chamber for manufacturing a semiconductor for depositing a plurality of chemical reaction products of the gaseous material on the wafer as a thin film, the semiconductor manufacturing chamber comprising at least one heating heating wire arranged between the inlet pipe and the wafer. . In this case, the at least one heating wire is characterized in that it generates heat at a temperature of 1000 to 2000 ℃ or less, respectively, the semiconductor manufacturing chamber is a susceptor is installed in the reaction region to support the wafer with a heater mounted therein Wow; Further comprising a power supply for supplying power to the heater, wherein the at least one heating wire is made of a metal material electrically connected to the power supply is characterized in that it generates heat in a resistance heating method. In addition, the heating wire is characterized in that one of the heating wire is zigzag repeated so that the parallel to each other on the same plane or a plurality of heating wires are selected from the cross-section crosswise longitudinally. In addition, the at least one heating wire has a larger inner diameter than the wafer so that each of the at least one heating wire is inserted into each other, and further comprises at least one ring-shaped frame fixed between the inlet pipe and the wafer, the heating wire is In the present invention, the heating wire is one selected from a mesh shape in which one heating wire is zigzag and repeatedly fixed to be parallel to each other on the same plane in the at least one frame, or a plurality of heating wires cross each other in a longitudinal direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Correct embodiments will now be described in detail with reference to the accompanying drawings.

FIG. 2 is a schematic cross-sectional view schematically illustrating a thin film deposition chamber 110 having a heating unit 150 according to the present invention, which is a sealed container defining a reaction region 112 in which a wafer 5 is seated therein. The chamber 110, which is a reaction container, has an inlet pipe 114 for supplying gaseous material transferred from the outside to the reaction zone 112, a discharge pipe 116 for discharging the gaseous material therein, and a pump installed at an end thereof. In particular, the internal reaction region is provided with a wafer table for supporting the wafer 5, for example, the susceptor 120. In the susceptor 120, a heat-generating heater 122 may be mounted to assist the chemical reaction between the gaseous substances introduced into the reaction region 112. A resistive heating method that generates heat may be used, and for this purpose, the power supply device 124 may be included in the chamber 110.

However, according to the present invention, the heating unit 150 terminating between the wafer 5 and the inlet pipe 114 is installed in the reaction region 112 of the chamber 110, which heats the gaseous material passing therethrough. Thereby lowering the activation energy. Accordingly, at least one heating wire installed between the wafer 5 and the inlet pipe 114 as shown in FIGS. 3A to 3B so as to effectively heat while minimizing the influence on the gaseous material in the reaction region 112 ( 152a or 152b).

At this time, Figure 3a is a perspective view schematically showing the internal structure by limiting only a part of Figure 2 to explain the heating unit according to the present invention, Figure 3b is a schematic perspective view of a chamber internal structure adopting another modification of the heating unit according to the present invention In bar, these are divided into first and second heating parts 150a and 150b for convenience, but have substantially the same configuration. Each of the first heating part 150a or the second heating part 150b includes at least one first heating wire 152a and a first heating wire 152a installed between the wafer 5 and the inlet pipe 114 into the reaction region 112, respectively. And a first frame 151a, a second heating wire 152b, and a second frame 151b, wherein the first frame 151a and the second frame 151b are respectively the first or second heating wire 152a or 152b), and preferably has a circular ring shape having a diameter larger than that of the wafer 5. Therefore, the gaseous material introduced into the reaction zone 112 through the inlet pipe 114 passes through the first or second frame 151a or 151b, and these frames 151a and 151b are respectively described in accordance with the present invention. The first or second heating wire 152a or 152b does not have any function other than the role of being fixed to be fixed between the inlet pipe 114 and the wafer 5, the shape of which is according to the purpose as shown in FIG. 112) It is also possible to form part of the sidewall, or may be mounted on the susceptor 120, including a plurality of supports protruding to the bottom as shown in FIG. Any other modifications will be apparent to those skilled in the art through the following description.

The essential elements of the heating unit according to the present invention are at least one or more first and second heating wires 152a and 152b arranged between the wafer 5 and the inlet pipe 114, which will be described together with the reference numeral 152. do.

The heating wire 152 is made of a metallic material such as copper, tungsten, or platinum, when the power is supplied, characterized in that the resistance heating method that generates heat at a temperature of 1000 to 2000 ℃ or less, the power to the heating wire 152 The power supply unit 124 for driving the heater 122 mounted in the susceptor 120 of FIG. 2 may be used. In addition, at least one of the heating wires 152 may be zigzagly wound to be parallel to each other on the same plane along each of the frames 151a and 151b, as shown in FIG. 3A or 3B, in order to maximize the contact area with the gaseous material. Alternatively, it may also be possible to have a plurality to cross the length and breadth to implement the net shape.

As a result, the heating wire 152 according to the present invention is disposed between the inlet pipe 114 and the wafer 5 to heat the reactant material flowing toward the wafer 5 in the reaction region 112 of the chamber 110. As long as this object is achieved, the arrangement may also be modified as much as possible, and in particular, if necessary, it may be arranged in multiple layers or other methods may be considered.

The chamber 110 including the heating unit 150 according to the present invention described above may have a more excellent effect, especially when applied to the atomic layer deposition method, it will be briefly described.

Atomic layer deposition is commonly abbreviated as Atomic Layer Deposition (ALD), which is very popular in recent years because it has excellent uniformity and step coverage characteristics and can realize high purity thin films. Is one of.

This may be classified as a chemical vapor deposition method in that a chemical reaction is used between two or more gaseous substances, but a conventional chemical vapor deposition method simultaneously introduces a plurality of reaction gases into a reaction zone in which a wafer is present, thereby reacting products thereof. Is deposited on the surface from above the wafer and is deposited in that the chemical reaction between the reaction gases is limited only on the wafer surface.

Accordingly, a plurality of reaction gases are sequentially introduced into the reaction zones, and at the same time, a purge process for removing residual substances in the reaction zones before and after each reaction gas introduction step is essentially performed. In the case of depositing a + B compound thin film, a first sub-step of adsorbing A material on the surface of a wafer by first introducing a first reaction gas containing A into a reaction region in which a target wafer exists is described. Proceeds.

Subsequently, a first purge process of removing all the remaining materials except the A material adsorption layer adsorbed on the wafer surface proceeds to a second sub-step, and then a second reaction gas containing B is introduced into the reaction zone. Three substeps are performed. At this time, since the adsorption layer of the A material exists on the upper surface of the wafer, a part of the B material included in the second reaction gas introduced into the reaction zone reacts with the A material adsorption layer on the wafer surface to form a thin film of A + B compound. Finally, a second purge process for removing all the gaseous substances present in the chamber is performed in a fourth sub-step.

When the above-described first to fourth sub-steps are performed once in order, a thin film of very thin thickness of A + B compound is deposited on the surface of the wafer, and the above-described first to fourth until the thin film of the desired thickness is realized. The process is completed by repeatedly repeating the thin film deposition cycle defined by the sub-steps several tens to several hundred times.

Therefore, when using the atomic layer deposition method, there is an advantage in that an excellent thin film can be realized, but productivity is inevitably reduced compared to the general chemical vapor deposition method, and the pressure of the gaseous material flowing into the chamber can be limited. Plasma or preheating method is difficult to use, but the heating unit according to the present invention has the advantage that the inlet pressure of the reactant is not limited because the gas is passed through the arrangement of a plurality of heating wires in the chamber.

Hereinafter, a method of implementing a semiconductor nitride film (Si ₃ N ₄ ) or an oxide film (SiO ₂ ) by the atomic layer deposition method described above through a chamber equipped with a heating unit according to the present invention with reference to FIGS. 2 and 3A to 3B. Explain.

In this case, at least one gaseous material among NH ₃ , N ₂ O, and O ₂ may be used as the first gas S ₁ flowing into the chamber 110, and SiH ₄ and Si ₂ H ₆ may be used as the second gas S ₂ . Each selected one is used. First, after the wafer 5 is loaded and seated on the susceptor 120, the chamber 110 is loaded into the chamber 110 in which the heating unit 150 is mounted. When closed, the reaction zone 112 is decompressed through the discharge pipe 116 and the pump P installed at the end thereof.

At the same time, the heater 122 mounted in the susceptor 120 and the plurality of heating wires 152 included in the heating unit 150 according to the present invention are each electrically heated, and these are one power supply device 124. It can be heated to share the above has been described above. Thereafter, at least one gaseous substance of NH ₃ , N ₂ O, O ₂ , which is the first gas S ₁ , is introduced into the reaction zone 112 through the inlet pipe 114. It is heated while passing through 152 and partially pyrolyzed.

Figure 4 shows that NH ₃ gas is pyrolyzed while passing through a plurality of heating wires according to the present invention in this step, NH ^{2 +} , H ⁺ , by the heating wire to heat to a temperature of 1000 to 2000 ℃ or less; It is activated in the form of a radical such as NH and flows to the wafer 5. At this time, since the heater 122 on the susceptor 120 also heats the wafer 5, the NH ₃ gas is further decomposed into radicals on the surface of the wafer 5, which is the heating part 150 according to the present invention. Is adsorbed on the surface of the wafer 5 together with the pyrolyzed radicals.

Subsequently, a first purge process proceeds as a second sub-step, which is made possible by driving the pump P while injecting an inert purge gas P ₁ such as Ar into the reaction region 112. Accordingly, the residual material except for the first gas (S ₁ ) component of the radical form adsorbed on the wafer 5 is removed in the chamber 110, and then a second gas selected from SiH ₄ and Si ₂ H ₆ ( A third sub-step, in which S ₂ ) enters the chamber 110, proceeds. At this time, the second gas S ₂ also passes through a plurality of heating wires 152 according to the present invention, in the form of radicals having low activation energy. After decomposition, the thin film of the semiconductor nitride film Si ₃ N ₄ or the oxide film SiO _{2 is} formed by reacting with the radical component of the first gas S ₁ on the surface of the wafer 5.

Subsequently, a fourth substep of removing all residual gases in the chamber 110 except for a thin film of the semiconductor nitride film Si ₃ N ₄ or the oxide film SiO ₂ is performed, which is the same as the above-described second sub-step. It is possible by introducing an inert purge gas (P ₂ ) such as Ar into the chamber. The thin film deposition cycle defined in the above-described first to fourth sub-steps is repeatedly performed several tens to hundreds of times. The semiconductor nitride film (Si ₃ N ₄ ) or the oxide film (SiO ₂ ) of the thickness is implemented.

In this case, it can be easily understood through the above description that a more improved effect can be expected as needed by properly turning on / off the power supplied to the heating wire 150 according to the present invention. .

The present invention provides a chamber for manufacturing a semiconductor including at least one heat generating heating wire arranged between an inlet tube and a wafer into a reaction zone, thereby minimizing thermal shock applied to a wafer, thereby enabling an improved thin film. Have. In particular, the present invention is relatively simple in configuration, but the advantages obtained through this may be very large. In this case, as a heating wire according to the present invention uses a metal material that generates heat in a resistance heating method, it is included in a general semiconductor manufacturing chamber. Since the power supply of the heater mounted in the susceptor can be shared, it can be constructed at low cost.

In particular, the present invention has a greater effect when applied to the atomic layer deposition method, the general atomic layer deposition method has the disadvantage that the film quality is somewhat poor as the process proceeds at a low temperature compared to the chemical vapor deposition method and the process speed is slow have. However, the use of the semiconductor manufacturing chamber including the heating unit according to the present invention has the advantage that can significantly increase the ratio of the radicals of the activated reactor in the reaction zone, while maintaining the temperature of the wafer as before, higher productivity is Of course, it has the advantage of realizing an excellent thin film.

Therefore, the main application of the present invention may be a chamber for manufacturing a semiconductor for an atomic layer deposition method.

Claims (6)

Defining an enclosed reaction zone in which a wafer is seated therein, and including an inlet pipe for supplying a plurality of gaseous materials from the outside to the reaction zone, wherein the chemical reaction products of the plurality of gaseous substances generated in the reaction zone are A chamber for manufacturing a semiconductor deposited on a wafer as a thin film, At least one heating heating wire arranged between the inlet pipe and the wafer Chamber for manufacturing a semiconductor comprising a The method according to claim 1, The at least one heating wire is a semiconductor manufacturing chamber that generates heat at a temperature of 1000 to 2000 ℃ or less, respectively The method according to claim 1 or 2, The semiconductor manufacturing chamber includes: a susceptor installed in the reaction region to support the wafer with a heater mounted therein; Further comprising a power supply for supplying power to the heater, The at least one heating wire is made of a metal material electrically connected to the power supply device semiconductor manufacturing chamber for generating heat in a resistance heating method The method according to claim 3, The heating wire is a chamber for manufacturing a semiconductor, wherein one heating wire is zigzag-repetitively repeated so as to be parallel to each other on the same plane, or a plurality of heating wires are selected from each other in a mesh shape that crosses each other in a longitudinal direction. The method according to claim 3, At least one ring-shaped frame having an inner diameter larger than that of the wafer such that the at least one heating wire is terminated and fitted inside the at least one heating wire, and is fixed between the inlet pipe and the wafer Chamber for manufacturing a semiconductor further comprising The method according to claim 5, The heating wire is a chamber for manufacturing a semiconductor, wherein one heating wire is zigzag-fixed repeatedly so as to be parallel to each other on the same plane into the at least one frame or a mesh shape in which a plurality of heating wires cross each other longitudinally and horizontally.