TW538462B - Cold wall chemical vapor deposition apparatus and cleaning method of a chamber for the same - Google Patents

Abstract

A cold wall chemical vapor deposition apparatus includes: a chamber; a susceptor movable up and down in the chamber by a driving means, the susceptor including a heater and an internal electrode; a heat reflector over the susceptor, the heat reflector reflecting a heat emitted from the heater back to a wafer on the susceptor and serving as an correspondent electrode to the internal electrode; a heater control unit connected to the wafer, the heater and the driving means, the heater control unit sensing a temperature of the wafer, the susceptor moving according to the temperature; a gas supply unit supplying gases to the chamber; and a power source applying a voltage to the chamber.

Description

V. Description of the invention (1) [Background of the invention 1 · Field of the invention The present invention relates to a method for manufacturing a semi-cold cold wall chemical vapor deposition, especially a method. Top of this δ—the clean side of the chamber 2 · Description of related technologies Description of various fields of development of new materials in various fields uLSI) Various integrated circuits: Ί and as fast as the super large product P annihilates 1 Development and development. That is, due to the new material, the conductive layer, and the conductive layer. Horses are used to form structures such as insulating layers and semi-unitary regions; the new thin films also serve as large-scale integrated circuits (Lsi) of two LS fathers. When society progresses to the condition of complete removal of electricity-conductor-conductor = jin = fayou ^: r Compared with other deposition methods, the chemical vapor deposition method has f. Even if it is worried, it has been often used in manufacturing methods of semiconductor devices. The selective epitaxial growth (SEG) method by which a crystal is selectively grown on a specific region of a substrate by a chemical vapor deposition method to form a thin film is used for a type integrated circuit (LSI) or the above-mentioned super-large integrated circuit Circuit (ulsi) special and body pen manufacturing process. Now, especially selective crystal growth is 538462. 5. Description of the invention (2) The method is used to form an insulating film such as silicon oxide (SiO2) or silicon nitride (Si3N4) in a line pattern on a stone substrate and Integrated circuit manufacturing process for selectively accumulating silicon films in exposed areas of a silicon substrate. ^ Figure 1 is a schematic plan view of a conventional hot wall chemical vapor deposition apparatus. Thermal chemical vapor deposition equipment 2 is one of the facilities for selective epitaxial growth of silicon. The hot wall chemical vapor deposition apparatus 2 includes a chamber 4 and a wall portion of the chamber 4 heated by a three-block resistance heater 6. The process of forming a silicon thin film on a wafer in the preparation of hot wall chemical vapor deposition is as follows. First, the word circle is loaded into the chamber & of the hot wall chemical vapor deposition apparatus 2, and then a source gas, which grows into a thin film, is supplied into the chamber 4. Next, the chamber 4 is heated by the tri-amplifier heater 6. Then, in the high-temperature strip 1 of the chamber 4, a silicon thin film is formed on the wafer by growing silicon crystals on the wafer. In order to heat the wall portion of the chamber 4 to a high temperature, it is difficult to deposit the source gas on the inner surface of the wall portion of the chamber. The source gas is within the chamber 4: The accumulation has the following disadvantages. First, due to unintentional deposition, gains are lost. Second, when the deposition process is completed and the chamber 4 is cooled, the rate of the chamber 4 is caused by the collapse between the chamber-to-wall portion and the thin film deposited on the chamber wall portion. Third, due to the internal strips of the chamber 彳 and the temperature of 7 ° C, source gas systems such as Shi Xi Jia Shao Shi Xi Ya (Sl2H6) deposited on the inner wall of the chamber are actively gasified, because (Si3 ^ growth exceeds Therefore, it is difficult to make Shixi crystal wind grow more than 500 angstroms under such conditions. Therefore, cold-walled 悤 # version is used to overcome the above problems. Pre-vapor deposition equipment has been proposed

Page 8 538462 V. Description of the invention (3) The cold wall chemical vapor deposition equipment includes a chamber and a crystal seat in the chamber. The wafer holder includes a heater positioned therein. After evacuating the inside of the chamber, the wafer heater was started to heat the wafer seat. When the wafer base is heated by a heater, it also indirectly heats the wafer on the wafer base. FIG. 2 is a cross-sectional view showing a conventional cold wall chemical vapor deposition apparatus. The conventional cold wall chemical vapor deposition apparatus 20 includes a chamber 22, an exhaust unit 30, and a body supply unit 24. The chamber 22 is where the thin film deposition and electrical grounding are performed. The crystal base 36 is positioned in the cavity 22, and a crystal 34 formed of a silicon material is loaded on the crystal base 36. The exhaust units 28 and 30 are used to exhaust the air in the chamber 22. The gas supply unit 24 is used to store the source gas and supply the source gas into the chamber 22. The exhaust units 28 and 30 are composed of a first exhaust unit 30 and a second exhaust unit 28. The first exhaust unit ⑽ is used for the entire area inside the chamber 22, and the second exhaust unit ㈣ is mainly used around the crystal base 36. The exhaust units 28 and 30 include ultra-high vacuum (UHV) exhaust systems using turbo molecular pumps, so the interior of the chamber 22 also includes ultra-high vacuum exhaust systems, especially for thin film deposition processes. The periphery of the wafer base 36 will become a super vacuum state. The wafer base 36 is fixed on the bottom of the chamber 22, and the wafer 34 on which the thin film is to be deposited is placed on the wafer base 36. The wafer base 36 is generally composed of a silicon material forming a wafer. For example, graphite or silicon carbide (SiC) will not damage the material of the wafer 34. The wafer base 36 includes a heater and an internal electrode 38. With the same material as the thin film formed on the wafer 34 °, heat reflection H32 'and positioning the heat reflector 32 above the base 36. The emitter 32 reflects the radiant heat emitted from the wafer 34 and the base 36 and returns. To the wafer 34 to improve the heating efficiency of the wafer 34 acting in the chamber 22: 538462 V. Description of the invention (4) During the thin film deposition process, the thin film material should not only be deposited on the wafer, but also should not be deposited on thermal reflection. Therefore, the thermal reflector 32 is formed by using the phase of the thin film on the wafer 34 as the material to prevent the thin film material deposited on the thermal reflector 32 from being easily separated from the thermal reflector 32. The radio frequency (RF) electrode 33 is formed in a thermal reflection | §32, which forms an electric field between the radio frequency (RF) electrode 33 and the internal electrode 38 by a radio frequency (RF) power source 35. The cold wall chemical vapor deposition apparatus 20 further includes a cooling device for cooling the wall portion of the chamber 22. 2 and 3, the thin film deposition process in a cold wall chemical vapor deposition apparatus will be described below. The wafer 34 is introduced into the chamber 22 from the outside through the slot valve 26, and then loaded onto the wafer base 36. The first exhaust unit 30 and the second exhaust unit 28 change the internal state of the chamber 22 to an ultra-high vacuum state of Tor 1. Since the wafer% is loaded on the wafer 36, the uranium has been heated by the heater 37, so the wafer 34 is heated to a temperature of usually 700 ° C, and then passed through the gas supply unit. 24 and the source gas is supplied into the chamber 22. At this time, since the inside of the chamber 22 is in an ultra-high vacuum state, the crystal circle 34 is reached by scattering of the source gas in the chamber 22. Since the wafer 34 has been heated by the heater 37 in the wafer base 36 as described above, when the source gas reaches the surface of the wafer 34, it is decomposed into various components and then deposited on the wafer 34. For example, an insulating film such as a silicon oxide (SiO2) film or a silicon nitride film is often used to form a line pattern on the surface of aa4. The surface of the wafer μ includes a surface area in which the materials constituting the wafer ^ such as Shi Xi are two-way in the working gas, and includes an insulating film such as an oxide dream ($ soil% film or a nitride nitride film (Si3N4) film) is exposed to the air. Surface ▲ domain. Because the reaction rate on the surface of Shi Xi is much higher than that on the surface of silicon oxide (Si 02) Page 10 538462 V. Description of the invention (5) The reaction on the surface of the film or the surface of the gasified stone (S N4) film Rate, it will selectively cause Shi Xi to only accumulate on the surface of Shi Xi on wafer 34. The cold wall chemical vapor deposition equipment 20 for selectively growing Shi Xi crystals on the surface of wafer 34 has To overcome some disadvantages. First, due to the irregular heating of the wafer 3 4, the thin film cannot be uniformly formed on the wafer surface. That is, the cold wall chemical vapor deposition equipment includes only the heater 3 in the wafer base 3 6. 7 is used as a heat source, so a temperature difference will occur between the upper surface of the wafer 34 and the lower surface of the wafer 34. The temperature difference between the upper surface and the lower surface will cause an irregular temperature of the entire wafer 34 Distribution, so the growth rate of silicon crystals will vary with the area of wafer 34 Because the deposition rate of the source gas on the wafer surface is proportional to the temperature of the wafer 34, the different temperature distribution on the wafer 34 will cause the thin film to not be uniformly formed on the wafer 34. If there are other elements already When formed on the wafer 34, the irregular deposition phenomenon becomes more serious due to the step difference formed by other elements. For example, when there is a temperature difference of 1 t, the deposition rate of polycrystalline silicon will be A difference of 2.0% to 2.5% occurs. Figure 3 is a graph showing the temperature difference between the wafer 34 and the cold wall in the conventional cold wall chemical vapor deposition equipment 20. As shown in the figure, the cold The temperature of the wall is often maintained at 20 ° C and the temperature of the wafer seat 36 is often maintained at 70 () χ: Therefore, there will be 25 between the surface of the taxi 34 of the wafer 34 and the surface below the wafer seat 36. Another disadvantage of the cold wall chemical vapor deposition equipment 2 is that the thin film is also not suitable. It is shaped on the thermal reflector 32 and then becomes a contaminating material. That is, if it is deposited during repeated deposition processes, Thin film deposited on the heat reflector 32 when the thickness of the heat reflector spoon film becomes thicker By the

f Page 11 538462 V. Description of the invention (6) Due to its weight, it becomes separated from the heat reflector 32 and floats in the chamber 22 in the form of a powder in the form of a powder. If these separated thin film particles adhere to the elements on the wafer 34, they will become impurities and reduce the reliability of the elements on the wafer 34. [Comprehensive description of the invention] Therefore, the present invention is directed to a cold wall chemical vapor deposition equipment and a method for cleaning a chamber of the equipment, which substantially eliminates one or more problems caused by the limitations and disadvantages of the related technology. An advantage of the present invention is to provide a cold wall chemical vapor deposition device, in which a crystal base is moved up and down during a thin film deposition process to overcome irregular thin film deposition on a wafer, and a thermal reflector is provided, and a window hole is provided thereon. It is coated or formed with quartz, or a silicon oxide (si%) is formed thereon. Another advantage of the present invention is to provide a method for cleaning a cold-wall chemical vapor deposition device ^ chamber, wherein the crystal seat system is moved up and down, and the direction of movement of a clean gas such as SF6 (SF6) electro-polymerized gas is moved. By changing the switching operation of the electrodes, the chamber can be cleaned more effectively than conventional cleaning methods. Other objects and advantages of the present invention will become clearer from the following detailed description and the scope of the accompanying patent application. In order to achieve the various advantages and objectives of the invention, as shown in the following specific examples and extensive descriptions, cold wall chemical vapor deposition equipment includes: a chamber; a crystal, which can be moved up and down in the chamber by a driving device, a crystal seat It includes a heater and an internal electrode; a heat reflector is located above the crystal base,

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V. Description of the invention (7) The heat reflector reflects a heat radiated from the heater back to the circle on the crystal base and serves as an opposite electrode connected to the internal electrode; a heater control unit, and a connection To the wafer, the heater, and the driving device, the heater control unit senses a temperature of the wafer, and the wafer holder moves according to the temperature; a gas supply unit supplies gas to the chamber; and a power supply, Apply one emperor to the chamber. In another aspect, a method for cleaning a chamber of a cold wall chemical vapor deposition device, the cold wall chemical vapor deposition device includes a crystal base with an internal electrode, a thermal reflector, and a crystal base. A driving device, a power source for selectively applying a voltage to a heat reflector or an internal electrode, and a gas supply unit include the following steps: supplying clean gas from the gas supply unit to the chamber; applying a voltage to the heat reflector and simultaneously Ground the internal electrode; apply a voltage to the internal electrode and ground the thermal reflector at the same time; and move the crystal holder up and down by a driving device while applying a voltage to the thermal reflection or the internal electrode. I should understand that the foregoing description and the following detailed description are for illustration and explanation, so that the present invention can be explained in more detail. [Detailed description of the preferred embodiment] The following describes embodiments of the present invention with reference to the drawings. The invention is characterized in that the cold wall chemical vapor deposition equipment comprises a movable crystal base and a heat reflector having a window hole and a heater control unit located thereon. The crystal base of the invention moves up and down, which can reduce the temperature difference between the upper surface and the lower surface of the wafer. Form the window hole of the heat reflector in the heat reflection

538462

This method can control the film material from being deposited on the heat reflector. The heater control unit controls the temperature of the heater and the movement of the crystal holder. To the wafer 6 4 ′ 俾 to increase the heating efficiency acting on the wafer 64 to form the thermal reflector 62 and use it as another electrode for radio frequency (RF) electricity to form an electric field in the chamber 52. A cross-sectional view of a cold wall chemical vapor deposition apparatus according to the present invention is shown in FIG. As shown in the figure, the cold wall chemical vapor deposition apparatus 50 includes a chamber 5 2, exhaust units 58 and 60, and a gas supply unit 54. The chamber 52 is electrically grounded. 1 The exhaust units 58 and 60 are used to exhaust the air in the chamber 52. The gas supply unit 54 is used to supply a source gas material into the chamber 52. The exhaust unit is composed of a first exhaust unit 60 and a second exhaust unit 58. The first exhaust unit 30 is used for the entire area inside the chamber 52 and the second exhaust unit 58 is mainly used around the seat 66. Exhaust units 58 and 60 include an ultra-high vacuum (UHV) exhaust system using a turbo molecular pump. Therefore, the interior of chamber 52 also includes an ultra-high vacuum exhaust system, especially in the wafer holder for thin film deposition. The area around 66 will become ultra-high vacuum. The wafer holder is positioned in the chamber 52 = sub-supported by the supporter 68. The wafer 64 on which the thin film is deposited is placed on the wafer holder 66, and the wafer holder 6 is formed of the silicon material constituting the wafer. By way of example, materials such as graphite or silicon carbide (SiC) will not damage the wafer 64. The base 66 has a heater for heating the wafer 64 on the base 66 "and the second chamber 52 is formed. The internal electrode 6g is one of the electrodes of the electric field. The pedestal = moves up and down and is driven by a motor 7 () connected to the holder 68. The thermal reflector 62 is positioned on the upper part of the wafer seat "in the chamber 52. The gate radiates from the wafer 64 and the wafer seat 66 by reflection. A metal material is applied thereto, such as quartz or silicon oxide.

Page 14 538462 V. Description of the invention (9) Thin == window hole 63 in or formed on the heat reflector 62, and the gas phase sinker 2 is deposited on the heat reflector 62. The cold wall chemistry thermoacoustic heater control unit 65 'of the present invention controls the operation of the heater 67. : After the temperature is increased, the up and down movement of the crystal holder 66 is controlled, and the state control unit 65 is arranged in the chamber 5 2 ^ ^ ^ Xju is arranged outside the chamber 52.… 52 of the 'danjia Ground, the electrical structure of the vapor deposition equipment of Department 66. The crystal base 8. The controlled emitter 'that is, the external electrode is connected to the switching frequency') the electric lu) power source 82 ° switch 80 is used to selectively apply radiation It is also the same as that of the internal electrode 69 or the thermal reflector 62, and the remaining electrodes are grounded. That is, if the emitter electrode 6 9 is applied, Jiajiao + β 0 from 丨 L, electric η I ^ cry R9丨 Earth, ground 62, and if radio frequency voltage is applied to heat reflection: the internal electrode 69 is grounded. The selective action and grounding of radio frequency (RF) voltage is controlled by the switch 80. fU 总 Γ I see FIG. 4 ′ illustrates the thin film deposition process of the present invention. The wafer is transferred into the chamber 52 from the outside by the groove valve 56 and then loaded on the seat 66. With the first row The internal state of the air unit 60 and the second exhaust unit 58 and the 1 cavity ^ 52 then becomes an ultra-high true state of 108 Tour. Because the seat 66 is on the wafer The wafer 66 has been heated to a certain temperature, usually 700 ° C, by adding the state 61 before it is placed on the crystal holder 66, and then the source gas is supplied through the gas supply unit 54. Into the chamber 52. Because the interior of the chamber to 52 is in an ultra-high vacuum state, the source gas is scattered in the chamber 52 to reach the wafer 64. At this time, because the wafer 64 has already been as described above It is heated by the heater 67 in the pedestal 66, so when the source gas reaches

Page 15 538462 V. Description of the invention (10) When the surface of the circle 64 is decomposed into various components and then deposited on the wafer 64. For example, an insulating film such as a silicon oxide (Si02) film or a nitride nitride (SiM) film is often used to form a line pattern on the surface of the wafer 64. The surface of the wafer 64 includes a surface area where silicon and other materials constituting the wafer 64 are exposed to the air, and includes an insulating film such as a silicon oxide (si%) film or a silicon nitride (s) film. Surface area in the air. Because the reaction rate of 3 i on the silicon surface is much higher than the reaction rate on the surface of the silicon oxide (SiO2) film or the surface of the silicon nitride (SisN4) film, it will be selectively applied to the silicon surface of the wafer 64. The integrated cold wall chemical vapor deposition equipment 50 includes a movable crystal holder 66 which is moved up and down by a motor 70, and a heater control unit 65 which controls the operation of the stable. Above the circle 64 on the surface of the second plate = when there is a large temperature difference, the heater control unit; / two motors 70 to move the seat 66 toward the heat reflector 62, and "the temperature between the surfaces:". On the other hand, the top surface of circle 64 and the bottom surface of wafer 64 are different. 'If the black sequence of lambda 64 of wafer 64 is sensed and then the control unit 65 is controlled, the heater controls the heater control unit 65. At the same time, he held down: ^ and moved the seat 66 down. Keep at proper temperature. That is, the temperature of J 7 1567 enables the wafer temperature control to control the movement of wafer f / 64 and the heater 67 to perform wafer temperature control. The conventional method is to reduce the temperature of the wafer 64 only by the heater. The temperature control of the invented wafer will be ancient: for wind deposition equipment, there is a window hole 63 on the top of the 62 and the use of stone slabs =. In addition, because the thermal reflector, or vaporized silicon (S i 〇2) is coated or shaped, page 16, 538462, 5. Description of the invention (11) into the window hole 63, it can greatly reduce the unfavorable on the thermal reflector 62 Thin film deposition. After the thin film deposition process, the cleaning process of the chamber 52 is performed. The cold wall chemical vapor deposition equipment of the present invention is also superior in the clean processing of the chamber. Clean treatment. Conventional cold-wall chemistry Applying radio frequency (RF) voltage to heat reflection will clean the chamber such as sulfur hexafluoride (SF6) plasma. The sulphur (SF6) plasma gas is cleaned. The crystal base 6 6 can be moved up and down, and the density and distribution of the net gas between the thermal reflector 62 and the crystal base 6 6. Because of the conventional cold wall chemical vapor deposition, the chamber 52 is cleaned. The deposition device 50 includes a cavity to form a heat reflection ^ § 62 and the internal device 50 includes a switch 80. On) the voltage is applied to one of the two electrodes and at the same time the RF voltage is applied to the internal electrode 69, then the RF voltage is applied to the thermal reflector 62, and then) the selective action of the voltage is connected to ground. Therefore, if the chamber 52 is clean and the electrode gas is turned on and off by moving the plasma gas, then

In the following description of the chamber 5 2 vapor deposition apparatus according to the present invention, an electric field is usually formed in the chamber by an applicator, and then a clean gas of gas is supplied to the chamber. The clean process of the invention also uses a hexafluoronet And proceed. However, because of the fact that the sulphur hexafluoride (SF6) plasma gas can be controlled by the movement of the crystal base 6 6, compared with a fixed crystal base 6 6, the present invention will be more effective As described above, one of the two electrodes of the electric field in the cold wall chemical vapor phase chamber is the pole 69. In addition, the cold wall chemical vapor deposition process 80 is selectively applied with RF (^ f to ground the other electrode. That is, if applied to ground the heat reflection ^ § 62 2 and if applied to ground the internal electrode 69. RF (Rf changes the switching direction of the electrode during the process controlled by the switch 80 in this way to the opposite direction. If "=

Page 17 538462 V. Description of the invention (12) For example, instead of any plasma gas with opposite moving directions made by the present invention will be repeatedly generated in the chamber, so the chamber The cleaning of 5 2 can be performed more effectively than the conventional cleaning method using plasma gas moving in a single direction. =: Explain that the preferred implementation of the present invention is too much; this preferred embodiment. Where according to the scope of the 4 patents in this.

538462 Brief description of drawings Figure 1 is a schematic plan view of a conventional hot wall chemical vapor deposition equipment. FIG. 2 is a cross-sectional view showing a conventional cold wall chemical vapor deposition apparatus. FIG. 3 is a graph showing a temperature difference between a wafer and a cold wall in a conventional cold wall chemical vapor deposition apparatus. Fig. 4 is a cross-sectional view showing a cold wall chemical vapor deposition apparatus according to the present invention. 【Symbol Description】

2 Hot wall chemical vapor deposition equipment 2 0, 50 0 Cold wall chemical vapor deposition equipment 22, 52 Chamber 24, 54 Gas supply unit 26, 56 Slot valve 28, 30, 58, 60 Exhaust unit 32 > 62 Thermal reflector 3 3 Radio frequency (RF) electrode 34, 64 Wafer 35, 82 Radio frequency (RF) power

36, 66 Crystal holder 3 7, 6 7 Heater 38, 69 Internal electrode 4 Chamber 6 Resistance heater 6 3 Window hole

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Claims (1)

538462 6. Scope of patent application1. A cold wall chemical vapor deposition device, comprising: a chamber crystal holder can be moved up and down in the chamber by a driving device; the crystal holder includes a heater and an internal electrode; a heat reflection A heater is located above the wafer base, and a heat radiated by the thermal reflector is reflected back to a wafer and an opposite electrode of the electrode; a controller control unit is connected to the wafer, the heater is used for heating The controller control unit senses a temperature of the wafer and the wafer base moves according to the temperature; the supply unit supplies gas to and applies a voltage to the chamber. The heater is connected to the interior of a heating drive device, a gas, a power source and a mobile, which will be regarded as the connection, and the degree '2. If the cold wall of the first scope of the patent application applies to the heat reflector more Including the pre-rolled phase deposition equipment coated or formed, where the material is located under the thermal reflector-= such as the material of the oxidized stone (Si〇2) 3. such as the cold wall of the first scope of the patent application The driving device is a motor. + Vapor deposition equipment, of which 4. If the cold wall of item 1 of the patent application contains a switch, the electric / vapor deposition equipment is selectively applied, including reflection | 5. To the internal electrode or to the heat 538462 6. Scope of patent application 5 · The cold wall chemical vapor deposition equipment according to item 1 of the patent application scope further includes an exhaust unit to maintain a vacuum state of the chamber. 6. —A method for cleaning a chamber of a cold wall chemical vapor deposition device, the cold wall chemical vapor deposition device includes an internal electrode > a crystal base, a thermal reflection, and A driving device, a power source selectively applying a voltage to the thermal reflector or the internal electrode, and a gas supply unit include the following steps: supplying clean gas from the gas supply unit to the chamber; applying the voltage to The thermal reflector simultaneously grounds the internal electrode; applying the voltage to the internal electrode and grounding the thermal reflector at the same time; and moving the crystal holder up and down by the driving device while applying the voltage to the thermal reflection Device or the internal electrode. 7. The method for cleaning a chamber of a cold wall chemical vapor deposition equipment according to item 6 of the patent application, wherein the driving device is a motor. 8. The method for cleaning a chamber of one of the cold wall chemical vapor deposition equipment according to item 6 of the patent application, wherein the cold wall chemical vapor deposition equipment further includes a switch that selectively applies the voltage to the thermal reflection Device or the internal electrode. Page 22