KR100766303B1 - Methods and apparatuses for high pressure gas annealing - Google Patents

Abstract

A high-pressure gas annealing method and apparatus is provided to prevent hydrogen or other process gas from being discharged into an atmosphere for fabricating an integrated circuit device using a high-K gate insulating layer. An internal chamber is made of non-metal material and is designed to maintain first pressure of a first gas comprising at least one of hydrogen, deuterium, fluorine, chlorine and ammonia. An external chamber is made of metal material, and houses the internal chamber therein. The external chamber is designed to maintain second pressure of a second gas comprising inert gas from the outside of internal chamber. A holder is connected to the internal chamber to hold a semiconductor wafer in the internal chamber.

Description

METHODS AND APPARATUSES FOR HIGH PRESSURE GAS ANNEALING

1A is a cross-sectional view of a high pressure heat treatment apparatus of the prior art, including a gas chamber, a gas transfer device, and a gas exhaust system.

1B shows a high pressure process chamber of the prior art, showing a cross-sectional view of an O-ring used to seal the gap between the chamber and the chamber lid.

 Figure 2a shows a specific embodiment of the present invention, which uses a vertical high pressure gas chamber, and further includes an inlet gas transport device, a gas exhaust / exhaust system and a combustion scrubber.

Figure 2b shows a horizontal high pressure process chamber in accordance with an embodiment of the present invention, including an inner process chamber and an outer protective chamber.

3 illustrates an exemplary double wall chamber tube used in an embodiment of the present invention and includes an inner chamber and an outer chamber. The tube has two partitions separated by an inner chamber.

4 is a flow chart illustrating an exemplary process used in an embodiment of the present invention for protecting an inner chamber. If the pressure difference is greater than a certain preset value, the system automatically adjusts the pressure.

5 shows an inflow gas transport apparatus according to an embodiment of the present invention. The figure shows three configurations: process chamber, gas filter and gas partition control.

6 is a flow chart illustrating an exemplary method for simultaneously increasing or decreasing pressure in an inner chamber and an outer chamber in accordance with an embodiment of the present invention.

7 illustrates an exemplary exhaust / exhaust system used in an embodiment of the present invention. The system includes an extra gas line to prevent backflow of atmospheric air through the exhaust pipe.

8 shows a flow chart for discharging gas from multiple chambers at the same time according to this embodiment. In this method, the process gas is exhausted from one chamber and mixed with another gas in another chamber.

* Explanation of symbols on main parts of the drawings *

20. Tube pressure 21141. Internal (Reaction) Chamber / Quartz Tube

22,143. Wafer boat 23,144. Semiconductor wafer

24. 2-Zone Plug Heater 25. O-Rings

26,145. Gas injection device 27. Quartz cap

28. Bottom part of cooling metal plate 29. Decompression exhaust pipe

30,130. Shell pressure 31,132. Coolant line

32. Upper part of cooling metal plate 33,133. Insulator / Insulation Layer

34,134. 4-zone main heater 35,135. Shell pressure exhaust pipe

36,138b. O-ring 37. Tube top

38. Tube bottom 39. Tube body / outer cell chamber

40. Lower door lock 41,137. Pressure regulating valve

42. Exhaust stainless steel pipe 43,151. Dilution tank

44. Double-walled stainless steel pipes 45,152. (Burning) scrubber

46,153. Hydrogen / Deuterium Gas Control Panel / Cabinet 47. Nitrogen

48,51,54. Gas pipe 49,155. High pressure (hydrogen) filtration device

50. Shell nitrogen injection device 52. Shell nitrogen pipe

56,161. Nitrogen injection line 131. Shell chamber

139,147. Exhaust Pipe 142. Door End Cap

146. Nitrogen injection device 150. Nitrogen gas pipe

154. Other Gas Panels 156. Hydrogen / Deuterium Pipes

157. Exhaust Pipe 158. Stainless Steel Pipe

201.Outer chambers 202,204,207. door

203. Inner chamber 205. Inner chamber

206. Inside chamber 208,209,210. Hydrogen injection tube

211,212. Hydrogen Exhaust Pipe 213. Nitrogen Injection Pipe

215. Nitrogen discharge line 301. Gas filtration device

302. Hydrogen injection line 303. Gas control panel

304. Gas pipe 305. Process chamber

501. The first chamber 502. The second chamber

503,504. Exhaust Pipe 505. Mixing Tank

506. Exhaust Pipe 507. Gas Pipeline

The present invention relates to a method and apparatus for high pressure gas heat treatment, and to a general semiconductor manufacturing process.

Various other heat treatments are performed on the semiconductor wafer during the manufacturing process of the semiconductor device. As an example, to achieve an effective process at the interface, oxidation, nitriding, silicides, ion implantation and chemical vapor deposition (CVD) processes are performed on the semiconductor wafer. Hydrogen and deuterium heat treatment processes for improving the interfacial properties of semiconductor devices are generally known to be carried out at a high temperature of 400 ℃ ~ 500 ℃.

Key factors for an effective reaction include not only the process temperature, but also the processing time of a particular gas, the concentration of a particular gas and whether or not it contains a mixture of gases used for a particular application or treatment. These three factors are generally considered as independent variables that determine the efficiency of process progress. For example, processing efficiency will be improved by increasing the process temperature while maintaining a constant gas concentration. Similarly, treatment efficiency may be improved by increasing the gas concentration at the same temperature. It should be noted that semiconductor wafers become irreversible when the integrated circuit is exposed to excessive heat and, more precisely, gradually degrade the quality of the integrated circuit. This is, in part, due to the diffusion of the various carriers and the ions implanted on the wafer, their proportions increasing linearly with temperature. Each integrated circuit has an acceptable limit of total thermal leakage during the entire manufacturing process, which is related to the thermal budget of the circuit in the related art.

As technology and device structures approach nanometer sizes, limited thermal hysteresis requirements require lower processing temperatures and higher concentrations of process gases. However, increasing the gas concentration and lowering the treatment temperature has its own limitations not only because of the safety issues caused by the high concentration gas but also because of the efficiency at lower temperatures. Although similar treatment efficiencies can be achieved by increasing the treatment time without changing the parameters of temperature and gas concentration, the treatment time and temperature are considered together as part of the thermal history limitation. That is, for example, increasing the processing time has a similar adverse effect on the performance of the device as well as raising the process temperature.

Wafers in a hydrogen-containing forming gas heat treatment process generally include the following processing steps prior to encapsulation or other packaging processes, which are caused by various processes during the pre-fabrication of semiconductor devices as well as the sintering process. The process of repairing damaged damage is extensively performed, which is referred to as 'hydrogen heat treatment' in the present technology.

In general, the molding gas heat treatment process mixes about 2% to 10% of hydrogen (H ₂ ) with the remaining inert gas such as nitrogen (N ₂ ). Recently, however, 100% pure hydrogen and deuterium heat treatment has been shown to improve device characteristics and reliability, such as hot carrier reliability, transistor lifetime, and dangling bond reduction. Improvements in lifespan increase the device's interconductance. As part technology and structure are moving towards the sophistication of so-called "nanometer technology", new high pressure applications require the use of other gases such as fluorine (F ₂ ), ammonia (NH ₃ ) and chlorine (Cl ₂ ). For example, these other gases are very reactive or toxic. Heat treatment has generally been carried out at temperatures above about 450 ° C. in a forming gas atmosphere containing pure hydrogen (H ₂ ) and deuterium (D ₂ ), and higher temperatures tend to result in better performance. However, as the size reaches the range of 0.12 μm, the limit heat history after initial metallization requires a heat treatment temperature of 400 ° C. or below 400 ° C., thereby potentially reducing the effect of hydrogen heat treatment on semiconductor device performance.

As an alternative, high pressure heat treatments of hydrogen and deuterium have been proposed and some good performance improvements have been reported. In particular, the heat treatment of hydrogen and deuterium in high-K gate insulating films showed a significant performance improvement such as reduction of interfacial charge, dangling bond, and improvement of interconductance. The discovery is illustrated in US Pat. No. 6,913,961 and US Pat. No. 6,833,306. These improvements are very significant in the fabrication process of integrated circuit devices using high-K gate insulating films for the next generation of semiconductor device technology.

One of the main advantages of the high pressure technology is that it can effectively increase the reaction rate by increasing the gas concentration at high pressure. By increasing the pressure of the process gas, the density of the process gas will be increased. The gas concentration increases linearly with increasing pressure. For example, if 100% pure hydrogen is treated under high pressure at 5 atmospheres, the actual amount of hydrogen gas leaked into the semiconductor silicon is 5 times the concentration of pure 100% hydrogen gas at normal pressure. In the case of partial pressure conditions, when the silicon wafer is processed at 20% hydrogen concentration and 5 atmospheres, the silicon wafer is effectively leaked at the same pressure as 100% pure hydrogen concentration. Similarly, processing at a hydrogen concentration of 20% and 20 atm will result in four times the results of processing with hydrogen gas at 1% at 100% net concentration.

Increasing the pressure of the process gas makes it possible to reduce both the treatment temperature and the process time. Just as the thermal hysteresis limit has reached the "extreme limit level" and the part technology has reached the 45 nm range, high pressure processes in semiconductor manufacturing technology are the only effective solution to meet or exceed the requirements of numerous heat treatments. The high pressure process can provide the following benefits in comparison with the three process parameters mentioned above: reduced process time, reduced process temperature and reduced process gas concentration. (1) The process temperature can be reduced by increasing the pressure without changing the process time and gas concentration in order to obtain equivalent or similar process results. (2) The process time can be significantly reduced by increasing the pressure while keeping other parameters of the temperature constant without changing the gas concentration to obtain equivalent or similar process results. (3) The gas concentration can be reduced by increasing the pressure during a constant process time without changing temperature parameters in order to obtain equivalent or similar process results.

The application of high pressure hydrogen / deuterium processes to high-K gate insulating film annealing, post-metallization sintering and forming gas annealing in semiconductor manufacturing can achieve a significant improvement in device performance. . At a given process temperature and time, the thermal hysteresis in the process can be significantly improved in terms of increasing the lifespan of the device, improving interconductance and reducing dangling bonds, which are essential requirements for the development of component technology.

Although the semiconductor manufacturing industry was not able to implement this manufacturing technique in the production line, even though it was somewhat recognized that the performance of the semiconductor device was significantly improved under high pressure heat treatment, especially in hydrogen (H ₂ ) or deuterium (D ₂ ) atmospheres. One of the main obstacles was the variety of safety issues associated with conventional heat treatment devices, especially high pressure process chambers.

Some of the process gases are very reactive, flammable, toxic and dangerous. And when these gases are pressurized, the likelihood of gas leakage from the pressurized vessel or surrounding auxiliary subsystems increases and the risk is much higher.

For example, hydrogen / deuterium gas is highly flammable and may explode when a high concentration of hydrogen / deuterium leaks into atmospheric oxygen. In addition, the probability of leakage of hydrogen / deuterium is higher under high pressure conditions due to the small molecular size of high concentration hydrogen / deuterium. This has led to the slow development of high pressure hydrogen / deuterium process chambers in the semiconductor major equipment industry. The same was true for the use of flammable, toxic and harmful gases in high pressure process atmospheres.

The high pressure process system generally comprises three main parameters or subsystems: (1) high pressure gas process chamber (2) inlet high pressure gas delivery system (3) high pressure gas treatment (exhaust) mechanism after completion of the process . The most important of these is a process chamber or chamber, and in the process chamber or chamber, a semiconductor wafer is processed by pressurizing an active gas such as hydrogen. Chamber doors or covers are generally sealed with O-rings. If the O-ring cannot be sealed under high pressure and high temperature conditions, an active gas such as hydrogen may leak into the atmosphere. Other connections in the assembly, defects in the material, etc. can cause gas leakage and potentially lead to dangerous situations.

Another safety issue with high pressure hydrogen devices is influent gas control subsystems or modules, which are connected to flow meters, flow controllers (MFCs) and other gas control machinery. These connections are all potential sources of hydrogen leakage, and any weaknesses or defects in these connections cause dangerous conditions. Stainless steel pipes used to transport process gases are also part of the safety considerations. Although the quality of stainless steel pipes is generally very high today, any defect in the stainless steel itself can lead to the leakage of hydrogen under high pressure conditions.

Another important consideration in designing a high pressure heat treatment system is how to deplete active gases, such as hydrogen / deuterium, which are highly pressurized to the atmosphere at the end of the process. Pressurized hydrogen can reach concentrations of 100% and cause safety problems if not handled properly. Another safety concern concerns the environment of load locks where the process chamber is opened after the process has been completed and the gas has been depressurized, without breaking the vacuum of the entire vacuum system. Even after depressurizing the process gas, there is always the possibility of trapped residual gas in the chamber, and residual gas such as hydrogen can interact with atmospheric air.

In part because of these safety issues, although the high pressure hydrogen process is known to be very beneficial for the performance of semiconductor devices, the major equipment industry has been reluctant to invest the necessary capital to develop high pressure hydrogen processing equipment. Most reported high-pressure hydrogen treatment devices are prototypes used only as tested or used in settings only in the laboratory, as shown in FIG. 1A. 1A shows a cross-sectional view of a typical high pressure hydrogen process chamber in the prior art. It should be noted that the process chamber shown in FIG. 1A is a prototype or a laboratory model. This particular design of the high pressure process chamber may not be used in the production environment of the pre-semiconductor device fabrication process due to the safety concerns described above.

1a shows the main process chamber 10 (in this case made of stainless steel) and the chamber lid 11 which is the upper part of the chamber. In general, the chamber lid 11 is closed with an O-ring (not shown) when it is closed. Inside the main chamber 10, a heater 20, a reactor chamber 21, and a reactor lid 22 are superimposed together to support a semiconductor wafer (not shown).

The hydrogen / deuterium (H ₂ / D ₂ ) gas injection device or inlet port 15, the pressure sensor device 14, and the gas exhaust port 16 have a tube cover of an upper portion with respect to the inside of the main process 10. It is connected past (11). The main heating device is connected to the thermocouple temperature sensors 17 and 18, and both of the thermocouple temperature sensors 17 and 18 are connected to the temperature control device 12. The pressure sensor device 14 is connected to the temperature control device 12 and the pressure sensor device 13 again.

The design of the prototype type shown in FIG. 1A does not take into account the aforementioned safety issues, and this particular model is designed only for feasibility analysis. It should be noted that only the chamber is designed to hold a single wafer. The system is operated by loading the first wafer into the reactor chamber 21. The wafer is heated by the heater 20 and hydrogen gas is injected from the top through the gas injection device 15. The pressure sensor device 14 and the pressure sensor device 13 monitor the gas pressure in the main chamber while the thermocouple temperature sensors 17 and 18 monitor the temperature. Once the ideal gas pressure and temperature are reached, a typical heat treatment lasts about 30 minutes. After the process is completed, the hydrogen (H ₂ ) gas in the chamber is exhausted through the gas exhaust vent 16.

One of the weak points of this design would be the main O-ring used to seal the process chamber or chamber. This is depicted in FIG. 1B, where the main O-ring is clearly shown. FIG. 1B is a cross-sectional view of the main chamber 110 and the lid 111 of the main chamber, as in FIG. 1A. In the present embodiment, the main chamber 110 has a cylindrical shape. The outer part and the exhaust pipe such as the inlet gas pipe included in FIG. 1A are not shown in FIG. 1B for clarity.

As shown in FIG. 1B, the space between the main chamber 110 and the lid 111 is closed with an O-ring 109. O-ring 109 has the shape of a circular ring, and generally has a cross section, either circular or elliptical. In the figure the O-ring 109 is shown in a rectangular (rectangular) cross section. If the main O-ring 109 is at high pressure, hydrogen gas may leak out of the tube and ignite when leaked to atmospheric oxygen. This can cause a very extreme dangerous situation. Even under normal operating conditions, there was a problem in that the possibility of hydrogen leakage was greater around the O-ring.

 Accordingly, the present invention has been made to solve the above problems, provides a high-pressure heat treatment method of hydrogen or deuterium, integrated circuit device using a high-k gate insulating film for the next generation of semiconductor device technology It is an object of the present invention to provide a method and apparatus for high-pressure gas heat treatment that is very breakthrough in the production technology.

It is another object of the present invention to provide a method and apparatus for high pressure gas heat treatment that can prevent hydrogen or other process gases from being released directly into the atmosphere.

It is another object of the present invention to provide a heat treatment chamber and a process progress subsystem which minimize the gas leakage during process processing and overcome the safety problem.

It is another object of the present invention to provide one of the first high pressure processing systems using a net concentration of hydrogen / deuterium or forming gas that can be developed in the production environment of the semiconductor device pre-process.

Method and apparatus for high-pressure gas heat treatment according to an embodiment of the present invention to achieve the above object, a variety of heat treatment, post-metallization of high-pressure hydrogen or deuterium gas, such as high-K gate insulating film (post-metallization) It is used in various heat treatments such as sintering heat treatment and molding gas heat treatment, and the use of high pressure gas can significantly improve device performance. For example, it can improve the lifetime and interconductance of the device and reduce dangling bonds. One of the main advantages of high pressure gas heat treatment is that it can be achieved with reduced thermal hysteresis costs at given temperatures and given processing times in device performance, which is an essential requirement for improved device performance.

According to another preferred embodiment of the present invention, the high pressure process system uses a vertical chamber for hydrogen / deuterium heat treatment. In another embodiment, a horizontal process chamber is used for high pressure hydrogen / deuterium heat treatment. According to another embodiment of the present invention, the heat treatment chamber has a double wall chamber structure including an inner chamber and an outer chamber. In this embodiment, flammable, toxic and dangerous active gases are limited to the inner chamber only. The inner chamber is protected by an external pressure pressurized by another gas contained in the outer chamber. In some embodiments, an inert gas such as nitrogen is used for this purpose. This design provides a kind of buffer area in the event of a process gas leak from the inner chamber. In another embodiment of the present invention, one or more outer chambers are used to provide a protective multilayer or buffer area. Likewise the inlet gas transport subsystem or module and the exhaust gas exhaust subsystem are protected by various methods in some embodiments. In another preferred embodiment of the present invention, the inner chamber is made of a nonmetallic substrate such as quartz and the outer chamber is made of a metal or metallic alloy such as stainless steel. In some embodiments, both chambers are made of a metallic material having a high melting point.

In the double wall chamber design, the gas pressure in the inner and outer chambers is controlled by the same method. For example, when the gas pressure in the inner chamber is raised or lowered so that the pressure difference across the inner chamber wall remains within a range of predetermined preset values, the amount of gas in the outer chamber is increased or decreased. A pressure difference higher than a certain value may affect the integrity of the inner chamber, which may have a lower resistance or strength to the force caused by the pressure difference than the outer chamber.

 According to an embodiment of the present invention, high-pressure hydrogen / deuterium and noxious gas high pressure (100% pure) suitable for high-K gate insulating film heat treatment, post-metallization sintering heat treatment, and molding gas heat treatment in the semiconductor device manufacturing process. Pressure or partial pressure). In this way, a number of major stability problems associated with flammable and harmful gases such as high pressure hydrogen / deuterium, fluorine, ammonia and chlorine can be overcome. In various aspects, such as reduction, semiconductor device performance can be significantly improved.

Embodiments of the present invention provide the following advantages by enabling or practical heat treatment in a high pressure environment and, among other things, affecting three essential process parameters (process time, process temperature and concentration of process gas): . (1) While producing equivalent or similar process results, the process temperature can be reduced with increasing pressure without changing the gas concentration and process time. (2) While leading to the same process results, the process time can be significantly reduced with increased pressure, without changing the gas concentration while maintaining other parameters of the process temperature. (3) While producing similar process results, the process gas concentration can be reduced with increased pressure, without changing the temperature parameters while maintaining the process time. (4) The process time and process temperature can be reduced simultaneously with the increased pressure while the process gas concentration does not change. (5) Process time, process temperature and gas concentration can be simultaneously reduced with increasing pressure without affecting the process results. And, (6) the concentration of process gas, process time and process temperature can be reduced or reduced at the same time.

As mentioned earlier, the main safety issue is the possibility of gas leakage from the heat treatment chamber. The possibility of gas leakage increases under conditions of high pressure. For example, high concentrations of hydrogen gas ignite or explode when leaked into oxygen in the air. Embodiments of the present invention employ various methods and techniques that can prevent hydrogen or other process gases from being released directly into the atmosphere, while reducing the possibility of gas leakage into the atmosphere during operation of the heat treatment apparatus. In particular, the methods or techniques described above are used to minimize gas leakage during process processing of high pressure hydrogen / deuterium or other noxious gases in the heat treatment chamber or any subsystem connected to the heat treatment chamber. Embodiments of the present invention can be used at production sites.

The present invention provides an improved process chamber for processing wafers by pressurizing hydrogen. Process chamber Alternatively, the chamber has one or more openings for installing various chamber components, and O-rings used to seal the space between the chamber parts and the chamber door or cover of appropriately sized chamber parts. If the O-ring cannot remain sealed under high pressure or extreme thermal conditions, hydrogen may leak into the atmosphere, leading to potentially dangerous situations. In general, the probability of hydrogen leakage is higher around the O-ring or near any joint. Small molecules, such as hydrogen, can be transmitted if there is a defect in the solid metallic material of the chamber, even through the defect. According to one embodiment of the invention, the process chamber comprises an inner chamber and an outer chamber. Hydrogen or other active gases are limited to the inner chamber, and the inner chamber is protected by an external pressure pressurized by another gas contained in the outer chamber. This embodiment provides a buffer area against the leakage of highly reactive, flammable, toxic and dangerous noxious gases when leaking directly into the atmosphere. Inert gases such as nitrogen can be used in the outer chamber, which provides two main main functions that dilute the potentially harmful gases leaking from the inner chamber and, among other things, prevent direct gas leakage into the atmosphere. . According to one embodiment according to the invention, two vertical chambers are used, and one chamber surrounds the other chamber. According to another embodiment, the main chamber comprises two or more horizontal chambers. According to another embodiment, one chamber is used directly or indirectly to process, another chamber is used to enclose the process chamber and another type of chamber is used to process the process in various combinations.

In addition, some embodiments of the present invention provide a safe inlet, delivery, and control subsystem or module, which is connected to a flow meter, a flow controller (MFC), and other gas control machinery. In one embodiment, the connections between these devices are protected by additional partitions or cabinets. In another embodiment, the gas pipe is protected by a double wall structure. In some embodiments, an alarm or alarm system is connected to a subsystem including such a process chamber and gas line to detect any gas leaking out of the subsystem.

In another embodiment of the present invention, a safe exhaust system is provided, where pressurized hydrogen, which has reached 100% pure form, is released into the atmosphere after heat treatment. In some embodiments, the hydrogen gas is diluted by another gas during the exhaust process. According to one embodiment, the gas is discharged from the outer chamber and mixed with hydrogen / deuterium gas or other noxious or flammable gas from the inner chamber at the same time. According to another embodiment, another inert gas, such as nitrogen, is added during the exhaust process to reduce the concentration of active gas exhausted from the heat treatment chamber.

After the process has been completed and the gas used for various purposes has been depressurized, some trapped residual gas may still remain in the heat treatment chamber or subsystem. Trapped residual gas can eventually leak and interact with atmospheric air, causing a potentially hazardous situation. According to one preferred embodiment of the present invention, a method and apparatus are provided for safely removing residual gas remaining in a system after a process is completed or terminated. In some embodiments, this implementation can be realized by using a design that utilizes extra nitrogen flow around the exhaust valves or tubes of the heat treatment chamber.

Therefore, as summarized herein, the present invention provides pure high pressure or partial pressure hydrogen (H ₂ ), deuterium (D ₂ ) and other harmful gases (eg, F ₂ ) that can overcome many safety problems associated with conventional systems. , NH ₃ , Cl ₂ ) and heat treatment chambers and other process progress subsystems. The present invention provides one of the first high-pressure processing systems using net concentrations of hydrogen / deuterium or forming gases that can be deployed in the production environment of a semiconductor device pre-process. Embodiments of the present invention may be used for high-k gate insulating film heat treatment, post metallization sintering heat treatment, and molding gas heat treatment in a semiconductor manufacturing process.

These embodiments, features, aspects and advantages of the present invention according to the present invention can be clearly seen from the accompanying drawings and from the description and the appended claims.

The invention will be described in greater detail below with reference to the accompanying drawings, which illustrate various specific embodiments of the invention. The invention can be expressed in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, such embodiments are provided so that this disclosure will be fully appreciated by those skilled in the art. Likewise, various details are set forth as follows to provide a thorough understanding of the present invention. It will be apparent to those skilled in the art that the present invention may be practiced without these details.

 One of the basic requirements for the design of high pressure process chambers using hydrogen or other harmful gases is safety. Under controlled circumstances, diatomic or deuterium gases are relatively safe. However, concentrated hydrogen or deuterium is extremely flammable and can ignite or explode if leaked into the atmosphere or oxygen. The danger is even greater as the gas content of hydrogen / deuterium appeared in the atmosphere. The amount of gas in the gas molecules in a given volume of space increases in proportion to the pressure, and therefore the risk of explosion or the probability of sudden ignition of hydrogen increases as the gas is further pressured. At atmospheric pressure, concentrations of hydrogen as high as 7% raise serious safety problems. Under elevated pressure conditions, the safety problem increases linearly with gas concentration proportional to pressure. As mentioned earlier, this safety issue is one of the main reasons why major semiconductor equipment companies are reluctant to design and manufacture high-pressure hydrogen / deuterium process chambers that can be used in production. One of the most important considerations in design to provide a safe and controlled environment is to limit the process gas and to minimize the possibility of leakage into the atmosphere or the process gas.

In general, the design of a high pressure process system using hydrogen (and other gases) includes (1) the main process chamber, (2) the inlet high pressure hydrogen gas delivery and control system, and (3) the exhaust to exhaust high pressure hydrogen gas after completion of the process. Or three important parameters or subsystems of the mechanism. Various aspects of the present invention will be discussed with respect to these three subsystems. In the following description, hydrogen gas is mainly used as an exemplary process gas, and it should not be interpreted as being limited only to hydrogen gas. Unless most other cases are mentioned, in various embodiments according to the invention any gas which is generally reactive, flammable, harmful and dangerous can replace "hydrogen".

Firstly, the present invention provides an improved heat treatment chamber in which hydrogen is pressurized and the wafer is being processed. The heat treatment chamber is generally surrounded by an O-ring that seals between the chamber and the chamber door, as shown in FIG. 1B. In a typical chamber of the prior art, if the O-ring cannot maintain its tightness under high pressure, hydrogen gas may leak directly out of the chamber and cause a potentially dangerous situation. According to a preferred embodiment of the invention, the process chamber comprises a double wall chamber consisting of an inner chamber and an outer chamber. Hydrogen or other active gas is confined to the inner chamber, and the inner chamber is protected by an external pressure pressurized by another gas contained in the outer chamber. This embodiment provides a buffer area for cases of leakage of internal gas. According to another embodiment, two vertical chambers are used for the process chamber. One chamber encloses the other chamber. According to another embodiment, the process chamber comprises two horizontal chambers. In other words, one chamber surrounds another chamber. In certain embodiments two or more chambers are used.

Secondly, according to some embodiments of the present invention, an improved inlet gas transfer and control subsystem or module is provided, which subsystem or module is connected with a flow meter, a flow controller (MFC) and other gas control machinery. . In at least one embodiment, the various gas conditioning units as well as the connections between these devices are protected by additional partitions or chambers. When process gas from a device is leaked, the leaked gas will be confined to a protected partition. In some embodiments, the alert or alert system is activated when a gas leak is detected. The use of double wall or layered stainless steel pipes prevents or reduces leakage from gas lines in certain embodiments.

Third, according to one embodiment of the present invention, an improved gas treatment or exhaust system is provided, and the pressurized hydrogen gas is completed by being released into the atmosphere after heat treatment. In some embodiments, hydrogen gas is diluted by another gas during the exhaust process. According to an embodiment of the present invention, the gas is discharged from the outer chamber and mixed with hydrogen gas or other harmful gas or combustible gas in the inner chamber. In some embodiments, the volume of the outer chamber is larger than the volume of the inner chamber, and therefore it dilutes the process gas more effectively. Herein, the first preset value according to the present invention defines a value for setting a volume ratio between the first chamber and the second chamber. Preferably, the volume of the second chamber should be larger than that of the first chamber. In one embodiment, the volume of the outer chamber is three times the volume of the inner chamber. In some embodiments, other inert gases are added into the exhaust pipe during the exhaust process to reduce the concentration of active gases exhausted from the heat treatment chamber. After the process is complete and the gas is pressurized, some residual gas may remain in the heat treatment chamber or in some subsystems. Residual gases may leak and interact with atmospheric air, causing a potentially hazardous situation. According to an embodiment of the present invention, a method and apparatus are provided for safely removing residual gas remaining in a system after a process is completed.

Before describing various embodiments of the present invention in detail with reference to the accompanying drawings, some of the main features of the various specific embodiments are first summarized.

The present invention provides a high-pressure hydrogen / deuterium and noxious gas high pressure process apparatus (up to 100 atmospheres) for high-K gate insulating film heat treatment, post-metal sintering heat treatment, molding gas heat treatment and other process applications in semiconductor manufacturing environments. Provided are methods and apparatus for designing and manufacturing.

The present invention provides the design of a dual pressure mechanism to insulate high pressure hydrogen (tube pressure) from the atmosphere with the use of a high pressure nitrogen environment (shell pressure) to ensure the safety of the inner chamber or process chamber. Tube pressure is the pressure of an active gas, such as hydrogen / deuterium or other noxious gas in the inner chamber or tube, and shell pressure is the pressure of nitrogen or other inert gas in the outer chamber or shell. In some embodiments a quartz chamber is used as the inner chamber to separate shell pressure from tube pressure.

The present invention provides a method and apparatus for diluting hydrogen at tube pressure with shell pressure nitrogen during an emergency process interruption, while reducing the pressure in the process chamber after completion of the process. Furthermore, in some embodiments, additional diluents are used in combustion exhaust pipes or dilution tanks to dilute hydrogen / deuterium or other harmful gases. In this case, to ensure the safety of the exhaust gases, if necessary, complete combustion in a scrubber prior to release to the atmosphere.

Embodiments of the present invention provide for the design of closed gas control panel subsystems under vacuum or under nitrogen pressure, or to provide a hydrogen or deuterium sensor in a gas panel to prevent any hydrogen / deuterium from leaking from any connection or joint. The design provides safety to the gas control subsystem under high pressure conditions.

In the embodiment of the present invention, the high pressure process gas (H ₂ / D ₂ or F ₂ , installed between the process chamber of the closed gas control panel and the high pressure chamber, and the closed gas control panel and the gas source (pressurized gas filtration device or booster pump); NH ₃ , Cl ₂ , etc.) Provide safety to the atmosphere by installing double-walled stainless steel pipes for the flow pipes. In some embodiments, a double walled stainless steel pipe is installed between the process chamber and the exhaust pipe to exhaust the process gas. Double-walled stainless steel pipes have a second pipe outside the inner gas pipe to prevent the direct leakage of hydrogen into the atmosphere.

Embodiments of the present invention ensure the safety of the process by ensuring that nitrogen always flows in the loading zone through combustion to remove potential residues of hydrogen or deuterium when the door of the chamber is opened after completion of the process. In some embodiments, the exhausted nitrogen gas flows directly into the dilution tank, where the exhaust gas is diluted after mixing with other gases.

2A, a specific embodiment of the present invention including the three subsystems described above is described. In this embodiment, a vertical high pressure process system is used. According to this specific embodiment, the heat treatment chamber has a double wall chamber structure including an inner chamber and an outer chamber, and flammable, harmful and dangerous active gases are limited to the inner chamber. The inner chamber is protected by an external pressure pressurized by another gas contained in the outer chamber. This design provides a buffer area in the event of a process gas leak from the internal process chamber and therefore has two major advantages. That is, they dilute the potentially dangerous gas leaked from the inner chamber and prevent the leaked gas from being released directly into the atmosphere. In some embodiments, one or more outer chambers are used to provide a multi-layered and buffered area for protection. The main contour chamber or outer chamber shown in the figure includes three components: an upper end portion 37, a body portion 39, and a bottom portion 38. In some embodiments, the material of this outer chamber is made of 316 series stainless steel material with high stress points in pressure. The chamber top portion 37 is typically attached to the chamber body portion 39 by means of a screw, and the chamber bottom portion 38 is attached to the chamber body portion 39 by using the lower door lock 40. In the embodiment it is made of 316 series stainless steel. In this exemplary design, the chamber bottom 38 is separated from the main chamber when the chamber door is opened for loading and unloading.

Inside the main chamber is a four-zone main heater 34 that controls each heating zone independently. The main heater 34 is isolated from the chamber wall by the insulator 33. In this embodiment there is a two-zone plug heater 24 atop the chamber bottom 38, which can heat the wafer boat 22 or wafer holder. The wafer boat 22 holds the semiconductor wafer 23, and in some embodiments, the wafer boat is made of quartz. The outer main chamber has a coolant line 31 for preventing the chamber from overheating by the main heater 34 to exceed the safe temperature inside the chamber. A quartz cap 27 is positioned around the plug heater 24, and the quartz cap 27 has quartz spirals around the plug heater that will heat the incoming process gas with respect to the process temperature. Process gas enters the inner process chamber 21 / inner tube chamber through a gas injection device 26 for pressurizing the tube. In some embodiments, the inner process chamber 21 is made of a nonmetallic material, such as quartz, and the outer chamber is made of a metal or metallic alloy, such as stainless steel. In another embodiment, both chambers are made of a high melting point metallic material. The internal process chamber 21 is divided into two zones, and the gases in these two zones can be completely isolated and have different pressures. As indicated by 20 in the figure, the gas pressure inside the process chamber is referred to as the tube pressure, and as indicated by 30 in the figure, the gas pressure outside the process chamber is referred to as the shell pressure. The outer shell chamber is pressurized by a gas other than the usual process gas, which is very reactive and flammable and on the other hand can be dangerous. In some embodiments, an inert gas such as nitrogen is used for this purpose. Nitrogen is introduced into the outer chamber through the shell nitrogen injection device 50 in the specific embodiment shown in the figure. The figure also shows two cooling metal plates, the upper part 32 and the bottom part 28, which are in a temperature protection zone above the upper part 32 of the cooling metal plate and under the bottom 28 of the cooling metal plate from overheating. Used to protect the components. The shell pressure zone inside the outer chamber and the tube pressure zone inside the process chamber are separated and closed by an O-ring 25. O-ring 36 is also used to maintain shell pressure by preventing inert shell gas leaking out of the main chamber to the external environment.

In a double wall chamber design, tube pressure and shell pressure are controlled in an integrated manner. For example, when the pressure of a process gas (eg H ₂ ) in a tube increases or decreases, the gas volume of the inert gas in the shell is automatically increased or decreased by an automatic gas control system, which is automatically The control system monitors and controls the tube pressure and shell pressure so that the pressure differential across the inner chamber wall remains within the preset range. When pressurizing the chamber, the pressure increases in the shell and tube chambers that need to be balanced, and these chambers should in fact always be the same as each other chamber. In certain embodiments using quartz tubes, in general, the pressure difference between the shell pressure and the tube pressure can be tolerated by ± 2 atmospheres. When the tube is pressurized and hydrogen or deuterium gas begins to flow, shell nitrogen gas is simultaneously injected into the shell as a way to maintain the pressure difference within the desired range (eg ± 2 atmospheres). In a typical design of a double wall chamber system, the inflow of shell nitrogen in FIG. 2A is generally greater than that of hydrogen or deuterium because the outer cell chamber 39 is generally much larger than the inner tube chamber 21 in the figure. Big. In a similar case, when hydrogen gas is exhausted (eg after completion of the process), nitrogen and hydrogen are released simultaneously in such a way to maintain the pressure difference within the desired range.

The homogeneous or near homogeneous pressure of the shell nitrogen 30 and the tube hydrogen 20 will maintain the integrity of the quartz tube from collapse inside or out. When the tube is fully pressurized by hydrogen / deuterium or other active gases up to the specified pressure level, the shell is also pressurized by nitrogen or other inert gases at similar pressure levels. The difference between the shell pressure and the tube pressure (differential pressure) can approximate reaching higher and lower values up to 2 atmospheres in the tube for the particular design shown in FIG. 2A using a special dimension (not shown). . Under these conditions, hydrogen or deuterium under high pressure is completely isolated from the atmosphere due to the large amount of ambient nitrogen in the tube region during the high pressure process, thus preventing any leakage of hydrogen / deuterium.

When the high pressure process is completed, the tube pressure 20 will be exhausted through the decompression exhaust pipe 29, and the shell pressure 30 will be exhausted through the shell pressure exhaust pipe 35 controlled by the pressure regulating valve 41. will be. In the embodiment of FIG. 2A, both shell pressure and tube pressure are controlled by the same pressure regulating valve or valve set. When the pressure is released in the pressure regulating valve 41, nitrogen in the shell and hydrogen or other active gas in the tube are simultaneously evacuated for discharge. The exhaust gases are mixed, which effectively dilutes an active gas such as hydrogen with nitrogen and also maintains the pressure difference between the two chambers within the desired range. In the specific embodiment shown in the figure, at the point where the volume of the outer chamber is three times the volume of the inner chamber, the concentration of the process gas from the inner chamber is diluted to one third of its original concentration. For example, when a forming gas with 30% hydrogen is used during heat treatment, the hydrogen concentration in the exhaust pipe will be about 10%.

During the high pressure process, the leakage of hydrogen or other active gas from the tube to the cell will immediately dilute by surrounding the nitrogen in the shell. If the leak from the tube to the shell is large enough, ie while the leak from the shell to the tube is relatively small, the tube pressure will be reduced below the desired pressure range. In this case, the high pressure process will be interrupted in some embodiments due to software interlocking (a device that prevents the next operation from starting until the end of the ongoing operation). On the other hand, nitrogen leakage from the tube to the shell will mix with hydrogen (or other active gas) into the tube. This will result in dilution of the hydrogen (or other active gas) concentration. While the tube pressure remains relatively high, the interlock will also shut down in some embodiments to reduce shell pressure below the desired level when the leak is high enough. When the operation is stopped, the pressure regulating valve 41 discharges gas from both chambers, so that the shell pressure and the tube pressure are simultaneously released. When leakage from the shell occurs to the atmosphere, the shell pressure can drop rapidly, while the pressure in the tube is stable. In this case, the interlock will stop the process and in some embodiments stop the operation. When the shell pressure and the tube pressure dropped at the same time, it means that gas leaked from both the inner chamber and the outer chamber into the atmosphere. In addition, when the tube pressure and the shell pressure are disintegrated in the quartz tube and collapsed, for example, due to a differential pressure machine malfunction, hydrogen (or other active gas) is mixed and immediately diluted with the shell nitrogen, thereby reducing the risk. Let's go. Under such conditions, both the mechanical (hardware) and software interlocks interrupt the process to lower the pressure in both chambers and the pressure relief valve opens immediately. It will be appreciated that the pressure sensor devices in the inner chamber and the outer chamber can be connected to the control computer described herein, and such control can be implemented by means of a software program by the computer.

When the pressure regulating valve 41 is opened, the pressure in both chambers is simultaneously released while nitrogen and hydrogen gas are still under high pressure control. Hydrogen diluted with nitrogen in the shell should not leak to the atmosphere. Any defect in the exhaust pipe 42, generally made of stainless steel, will release hydrogen into the atmosphere. In order to prevent such unnecessary leakage from defects in the stainless steel pipe, the exhaust stainless steel pipe 42 in FIG. 2A is made of double wall stainless steel in some embodiments of the present invention. In a double walled stainless steel construction, if the first or inner gas pipe is defective and experiences a gas leak, the second or outer protective pipe will contain the leaked hydrogen in the pipe. Therefore, the probability that the gas leak will leak directly into the atmosphere is significantly reduced. Hydrogen diluted by the shell nitrogen enters the dilution tank 43 through the double wall exhaust pipe 42 and further before moving to another hydrogen / deuterium burning scrubber 45 through another double wall stainless steel pipe 44. Diluted. In the exhaust pipe, after the combustion of hydrogen and some combustible gas through the scrubber 45, it will release combustion residues into the atmosphere, as indicated by path 53 in the figure. In the exhaust pipe you will probably have condensation by water inside the tube. In particular, when the scrubber 45 is not used, it must generally have a much lower temperature than the exhaust gas due to the air flowing back from the atmosphere. Because water (H ₂ O) contains oxygen, condensation can react with hydrogen. This may be a source of safety issues. In some embodiments additional nitrogen is injected into the exhaust pipe to prevent condensation by water and to increase the dilution of hydrogen / deuterium. 2A shows a nitrogen inlet tube 56 directly connected to the exhaust pipe immediately after the exhaust valve, which serves as a constant source of nitrogen to ensure a constant external flow of gas from the exhaust port of the scrubber 45. do. According to one preferred embodiment of the invention, a low flow of nitrogen is maintained during normal operation to prevent condensation in the exhaust pipe and to maintain the outward flow of nitrogen from the scrubber 45. During chamber depressurization, the nitrogen flow rate may be increased to further dilute the potentially hazardous exhaust hydrogen / deuterium or other process gas depleted from the heat treatment chamber.

2A also shows a high pressure filtration device (bottle) 49 or a booster pump, which is a source of active gas such as hydrogen. The incoming process gas is introduced into the gas control panel or the cabinet 46 through the gas pipes 54 and 48, and the gas pipe between the gas injection device 26 (pipe 51 and the gas injection device 26 is clearly shown in the drawing). Not shown) and through the gas pipe 51 into the internal process chamber 21. The incoming hydrogen or deuterium gas can be 100% pure gas, the pressure of which is generally at least 500 PSI, so that the inlet gas pipes (eg 54, 48 and 51) and various parts around the gas filtration or pump May be one of the most dangerous zones in a high pressure system. The hydrogen injection line needs to be connected to (included in the gas cabinet 46) a gas control mechanism such as a flow controller or flow meter to control the flow. The gas connection and the gas control components themselves may be sources of hydrogen gas leakage under high pressure. Therefore, all inlet gas pipes 54, 48, 51 are double walled stainless steel pipes in some embodiments to prevent or reduce hydrogen leakage to the atmosphere. Additionally in accordance with one preferred embodiment of the present invention, the hydrogen / deuterium gas control panel 46 is separated from other gas panels, such as those used for nitrogen 47. The gas control panel 46 according to the present design is sealed under a pressurized nitrogen environment or under a vacuum environment. The hydrogen / deuterium gas control panel 46 needs to be generally sealed where all gas control components (not shown) are installed, and the hydrogen / deuterium detection sensor is installed within the control panel. The control panel can also be connected to the dilution tank 43. When a hydrogen leak is detected in the control panel, the exhaust pipe will open, an alarm will sound and the source gas line will shut off. According to an embodiment of the present invention, other gas pipes, such as nitrogen (N ₂ ) or oxygen (O ₂ ) gas pipes, use a stainless steel pipe surrounded by a single wall. For example, shell nitrogen pipe 52 and shell nitrogen injection device 50 from a nitrogen gas source of a duo or booster pump are single wall pipes as shown in the figure.

As mentioned above, in general, implementations of the present invention may be implemented with many other types of process gases, including net concentrations of hydrogen or deuterium. In some embodiments, two or more types of gas mixtures may be used at certain concentration ratios. In some other embodiments more types with a certain mixture concentration ratio may be used. In some other embodiments the invention system may have one or more high pressure filters 49 or other process gas sources, and the gas mixture of a predetermined mixture concentration ratio may be a gas injection system (eg, 46, 48 in FIG. 2A). And 51). In some other cases a gas mixture of 10% H ₂ and 90% N ₂ (ie, shaping gas) may be used as the process gas (eg in the gas filtration device 49). In other cases a gas mixture of 5% H ₂ and 95% N ₂ may be used. In another preferred embodiment of the invention 2% F ₂ or Cl ₂ and 98% N ₂ can be used. In some embodiments, shaping gas of 2% to 98% of deuterium mixed with other inert gases such as helium, nitrogen or argon may be used in the process. Also in some embodiments, the deuterium concentration may be between 1% and 99%, with the remainder being an inert gas. Therefore, the present invention is not limited to any particular process gas, and any kind of gas may not be used based on the application conditions.

In a typical process chamber design, another area where potential hydrogen leaks into the atmosphere is the loading zone of the chamber. When the chamber door is opened after the process is completed in the lower door lock in FIG. 2A, there is a possibility that some trapped residual hydrogen can be released to the atmosphere in the loading zone. In order to minimize the potential risk of hydrogen leakage, in some embodiments, the loading zone is formed with a horizontal plate of nitrogen flowing from one direction. According to at least one embodiment, the process gas injection mechanism (eg, 26 or 46 of FIG. 2A) is reused for this purpose. In this case, when the process gas is powered off, purging nitrogen or other inert gas from the nitrogen gas filtration device or gas pump (not shown) can be injected into the chamber through the gas injection device 26. (Note that the purging gas pipe is not clearly shown in the drawing). The loading area is shaped to exhaust the remaining hydrogen to the exhaust pipe or the dilution tank 43 connected to the dilution tank 43. In addition, in some embodiments, a hydrogen / deuterium (H ₂ / D ₂ ) sensing sensor will be included to monitor hydrogen leakage in the loading zone.

When the process chamber door is closed, there is a high possibility of trapping the atmosphere not only inside the shell chamber but also inside the tube chamber, which can result in interaction with hydrogen at the start of pressurization. As mentioned above, there is also the possibility of trapping hydrogen in the chamber when the chamber door is opened at the finishing stage of the high pressure process, which can react with oxygen in the atmosphere. In order to prevent this unintended residue reaction, in certain embodiments of the present invention, after the chamber door is closed prior to starting hydrogen pressurization, at the beginning of the process and then to purify the hydrogen trapped in both the shell and the tube. Use a process to purify nitrogen at the end of the process before opening the chamber door.

The embodiment shown in FIG. 2A uses two chambers in the vertical form, one surrounding the other. According to another obvious embodiment, the chamber comprises two or more horizontal chambers. In another embodiment, various types of different types of chambers are used, one or more chambers being used directly or indirectly for process progress, and other chambers are used to include process chambers. Such an embodiment is shown in FIG. 2B, where the double wall chamber high pressure process chamber comprises a chamber or tube horizontally inside and a chamber or shell horizontally outside.

The exemplary high pressure process system of FIG. 2B, with the embodiment shown in FIG. 2A, includes three main subsystems, which are the main process chamber, the inlet gas injection and control system, and the gas. Exhaust system. The main chamber configuration includes a shell or outer chamber, which includes a body 131 and an outer chamber or door 136 including a chamber bottom and a tube or inner chamber 141. In this embodiment, the outer chamber is made of 316 series stainless steel material having a high condensation point with respect to pressure, and the inner chamber is made of quartz. The chamber door 136 is separated from the main chamber 131 when opened for loading and unloading. One or more O-rings 138a are used to seal the space between these two components and to maintain pressure in the shell. Hydrogen or other process gases can potentially leak into the atmosphere around this loading area. There is the potential for some trapped residual hydrogen to be released to the atmosphere when the door is unlocked at the main door 136 and the chamber door is opened after the process is complete. In order to minimize the potential risk of hydrogen leakage, the loading zone is formed with nitrogen plates flowing in from one direction, and the nitrogen plates are also formed with trapping or exhaust pipes connected to the dilution tank 151. Additionally, in certain embodiments, the loading zone may include an H ₂ / D ₂ sensor to monitor hydrogen leakage.

In a vertical double-walled chamber design, the inner chamber or tube separates the main chamber into two separate regions, each of which contains a different gas and maintains a different pressure. In some embodiments, the shell pressure 130 is adjusted together so that pressures remain within a predetermined range depending on the pressure of the inner process gas, the tube pressure 140 and the pressure of the inert gas in the outer chamber. In this case the differential pressure is kept within ± 2 atmospheres, for example. The shell chamber 131 is pressurized by nitrogen introduced via the shell nitrogen injection device 146 connected to the nitrogen gas pipe 150, and the tube chamber 141 flows in through the gas injection device 145. Pressurized by sonar or deuterium. 2B also shows a semiconductor wafer 144 loaded perpendicular to the wafer boat 143 located inside the quartz tube 141. The inner chamber also includes a chamber door end cap 142. Shell pressure 130 and tube pressure 140 are closed by O-ring 138b, as in the embodiment of FIG. 2A. The outer main chamber has a coolant line 132 to shield radiant heat generated from the heater 134 inside the chamber. The four-zone main heater also includes an insulating layer 133. Each heater can be controlled independently.

When the high pressure process is completed, the pressure regulating valve 137 releases the accumulated pressure inside the chamber by releasing exhaust gas from both chambers. The tube pressure will be exhausted through the exhaust pipe 147 and the shell pressure will be exhausted through the shell pressure exhaust pipe 135. When the pressure regulating valve releases pressure, nitrogen in the shell and hydrogen in the tube are mixed and released simultaneously in the exhaust pipe 139, diluting the hydrogen with nitrogen through the exhaust pipe 157. In at least one embodiment of the invention, hydrogen diluted with shell nitrogen is transferred to dilution tank 151 via double wall exhaust 157 and further diluted there. In addition, some embodiments include a burning scrubber 152 connected to the dilution tank via another double walled stainless steel pipe 158, and hydrogen or other flammable exhaust gas is completely burned, as indicated by path 159 in the figure. And released into the atmosphere. The exhaust pipe 157 has the phenomenon of condensation by water inside the line due to the back stream of cold air from the air, especially if no scrubber is used. Condensation by water can react with hydrogen at high temperatures, leading to potentially dangerous situations. In order to prevent condensation by water and to further dilute the exhaust hydrogen / deuterium or other process gases, additional nitrogen is thereby injected in the exhaust pipe by providing the same function as the injection line 56 of FIG. 2A. The nitrogen inlet 161 is connected directly to the exhaust pipe behind the exhaust hole valve, and the flow of nitrogen is maintained to prevent condensation by water in the exhaust line. In some embodiments, the flow of nitrogen is increased during chamber depressurization to further dilute the exhaust hydrogen / deuterium gas.

The typical system of FIG. 2B also includes an inlet gas transfer and control subsystem, one of the most dangerous areas for the system because of the presence of high concentrations of high pressure process gases. The exemplary inlet gas transfer and control subsystem shown in the figure includes a high pressure hydrogen filtration device 155 or a booster pump and a hydrogen / deuterium gas cabinet 153. The incoming hydrogen or deuterium gas can be at a 100% concentration and the pressure is generally no less than 700 PSI. Gas is introduced into the hydrogen / deuterium gas cabinet 153 through the hydrogen / deuterium injection pipe 156 through the filtration device indicated by the path 160 in the figure. In some embodiments, hydrogen / deuterium injection tube 156 is a double wall stainless steel pipe. In the specific embodiment shown in the figure, the hydrogen / deuterium gas cabinet 153 is sealed or protected by a high pressure nitrogen environment or a vacuum environment. In addition, it is also separated from other gas panels 154 to ensure safety. According to an embodiment of the invention, a hydrogen / deuterium detector is installed inside the control cabinet, and the control cabinet is also connected to an exhaust pipe leading to the dilution tank 151. When a hydrogen leak is detected inside the control cabinet, the exhaust pipe will open and an alarm will sound and the source gas line will shut off.

3, a cross-sectional view of a double wall process chamber in accordance with an embodiment of the present invention is shown. The double wall process chamber includes an inner chamber 203 and an outer chamber 201 similar to the design of the exemplary chamber shown in FIG. 2A. In the design of the double wall chamber, flammable, toxic and dangerous active gases are defined in the inner chamber interior 206, which is protected by an external pressure pressurized by other gases contained in the outer chamber. In some embodiments, an inert gas such as nitrogen is used in the outer chamber. It should be noted that various parts including the support holding the inner chamber inside the outer chamber are not shown in the drawings for clarity. As mentioned earlier, this double wall chamber design provides a buffer area in the event of a leak of process gas from the inner chamber. In the illustrated embodiment, the inner and outer chambers are closed by lids or doors 204, 202, and 207, respectively. According to at least one embodiment of the present invention, the outer chamber is made of a metal such as 316 series stainless steel, and the inner chamber is the highest because it is made of a non-metallic substrate such as quartz to reduce contamination in high temperature and high pressure working environments. Has one of the stress points.

3 also shows various gas injection and exhaust lines. Note that these gas lines are shown as lined up in the figure. The figure also shows the coolant line 214. Process gas such as hydrogen or deuterium (H ₂ / D ₂ ) is injected through process gas injection pipes 208, 209, 210 and exhausted through process gas exhaust pipes 211, 212. On the other hand, an external chamber gas such as nitrogen (N ₂ ) flows into the chamber through the nitrogen injection pipe 213 and is exhausted through 215. In some embodiments, these gas lines can be reused for other purposes. For example, during loading and unloading, the nitrogen injection pipe 213 as well as the process gas injection pipes 208, 209, 210 may be used to introduce nitrogen for purifying the remaining process gas left in the chamber.

In the double wall chamber design, in FIG. 3, the pressure difference inside the inner chamber interior 206 and the outer chamber 205, respectively, is pressed over the surface of the inner chamber 203 wall. Inner chambers made of certain materials, such as quartz, collapse or break under high-pressure cars. In some embodiments of the invention, the pressure of the gas inside and the outer chamber is maintained within a predetermined range. For example, if the pressure of the gas in the inner chamber rises or decreases so that the pressure difference across the wall of the inner chamber 203 remains in a predetermined range, the amount of gas in the outer chamber is increased or decreased.

This is illustrated in the flowchart shown in FIG. 4. In this exemplary process, the pressure difference between the inner chamber and the outer chamber is kept within the predetermined range by blocks S251, S252, S253, S254 and S256 and trimmed in the loop. The process may be implemented with a computer programmed to read the pressure sensor device in both chambers and convert one or both pressures to maintain the pressure differential within the desired range. In block S251, the gas pressure (tube pressure) of the inner chamber and the gas pressure (shell pressure) of the outer chamber are measured, and in block S252, the pressure difference between the tube pressure and the shell pressure is calculated. If the pressure difference is within the initial preset value, these measurements are performed periodically or repeated based on changes in other conditions as indicated by the no path in block S253.

If the pressure difference is detected to be higher than the initial preset value, follow the 'Yes' path in block S253 and if it is detected to be lower than the initial preset value, follow the 'No' path in block S253 and block The process shown in S256 is performed. In this example, the pressure difference is adjusted by adding or removing gas to or from each chamber. The process then begins again by starting from block S251. If the pressure difference is higher than the second threshold, as indicated by the 'yes' path in block S254, it is terminated by shutting down the system, for example as indicated by block S255, and taking any necessary emergency action.

As mentioned earlier, the level of differential pressure tolerance, as shown in FIG. 2A or 2B, will be around 2 atm in a typical design of a double wall chamber. Shell pressures similar or essentially close to the tube pressure will maintain the integrity of the inner chamber, and in some embodiments the inner chamber is made of material such as quartz. Under carefully measured conditions, the pressure difference remains below the threshold, where hydrogen or deuterium gas in the inner chamber is isolated from the atmosphere by a large amount of nitrogen around the tube region, thus allowing hydrogen to enter the atmosphere during the high pressure process. To prevent leakage. Hydrogen leakage from the tube will immediately be diluted by the nitrogen around the shell. However, as indicated by block S255 of FIG. 4, if the leak is large enough to cause the pressure differential to increase beyond the preset threshold, the high pressure process is interrupted by software interlock in some embodiments. If gas from the outer chamber leaks into the inner chamber or into the outside air, similar precautions are taken, and the interlock stops the high pressure process when the pressure difference reaches a threshold. In some embodiments, both the differential pressure as well as the tube and shell pressures are monitored to detect what possible malfunctions in the system. When both the shell pressure and the tube pressure drop at the same time, or when the quartz tube separating the tube pressure and the shell pressure collapses due to a malfunction of the differential pressure, the mechanical and software interlocks will stop the high pressure process, and the pressure relief valve It opens immediately to empty both chambers.

In some embodiments of the present invention, a secure inlet gas injection, delivery and control subsystem is provided, which is connected to a flow controller, a flow meter and other gas control mechanisms. According to at least one embodiment, the connections between these devices are protected by additional partitions or chambers. A typical system is shown schematically in FIG. 5 and includes a gas filtration device 301, a process chamber 305 and a gas control panel 303. The gas filtration device 301 and the gas control panel 303 are connected through the gas pipe 302, and the gas is connected to the process chamber 305 through the gas pipe 304 in the gas control panel 303. In some embodiments, the gas line 304 is protected by a double wall structure, as described above. The minimum pressure of the gas filter or booster pump is typically 700 PSI, which is one of the most vulnerable connections to ensure safety in high pressure systems. Gas lines 302 and 304 into which hydrogen is injected are connected to various gas control mechanisms (not shown in the figure) or flow meters, such as flow controllers, and are generally included in gas control panels 303 for controlling flow. In some embodiments, the gas control panel 303 is protected by using additional machinery under pressurized nitrogen environment or under vacuum environment. This prevents hydrogen from leaking directly into the atmosphere. In some embodiments, an alarm or alarm system is used to detect gas leaks from gas control panels or from certain components, including gas injection tubes. When a hydrogen leak is detected inside or around the control panel, the exhaust pipe will open, an alarm will sound and the source gas line will shut off. In certain embodiments, the gas control panel is connected to the exhaust gas dilution tank, and the source gas can be discharged directly by passing through the process chamber in case of an emergency.

Another area where potential hydrogen leaks into the atmosphere is the loading chamber of the process chamber. The lower door and chamber door of FIG. 5 have the potential to release some trapped residual hydrogen into the atmosphere if the door is opened after the process is complete. In order to minimize the potential risk of hydrogen leakage, as described above in comparison to FIG. 3, some embodiments allow nitrogen to always flow in the loading zone. While nitrogen flows into the dilution tank, the hydrogen residue flows into the dilution tank along with the hydrogen. In addition, in some embodiments, the loading zone is equipped with a hydrogen sensor to monitor the hydrogen leak and triggers emergency actions (including the possibility of shutting down the system if a hydrogen leak occurs above a safe level). Will be initiated.

Figure 6 illustrates an exemplary process for applying pressure to a process chamber in accordance with an embodiment of the present invention, where a double wall chamber is used. When pressure is applied to the double wall chamber, the pressure increases in the inner chamber and the outer chamber must be carefully controlled. Here, the second preset value according to the present invention is to define a value that sets the pressure ratio between the first chamber and the second chamber, and preferably the first chamber is maintained at a high pressure at all times. To prevent the outflow of gas from the gas and adjust the concentration of the mixed gas, Typically the differential pressure should remain below a preset value, for example 2 atm. The flowchart depicted in the figure describes an atmospheric process in a discontinuous locking step, and the loop is formed to include blocks S401, S402, S403, S405, and S406. However, in other embodiments, this process may be performed continuously. As shown in block S401 of FIG. 6, an exemplary process adds a constant gas amount x of the first gas (process gas in the inner chamber) and a constant gas amount of the second gas (inert gas in the outer chamber). starts by adding y. In a typical design, the volume of the outer chamber is much larger than the volume of the inner chamber so that the gas volume of the second gas must be proportionately larger in order to equalize the pressure.

These gas quantities x and y are generally quantities that can be calculated based on the particular design of the chamber. For example, the injection gas amount can be controlled in various ways, such as varying the injection pipe used for different diameters or the injection time. Then, the tube pressure and the shell pressure are measured (block S402), and the pressure difference is calculated (block S405). If the tube pressure and the shell pressure are essentially close to the target value, the process ends at block S404. On the other hand, in other cases the process continues. If the pressure difference remains within the range of the preset value, the atmospheric pressure process continues along the 'no' path in block S405. In other cases, some additional processing is obtained at block S406 to balance shell pressure and tube pressure.

With reference to FIG. 7, an exemplary exhaust system is described in accordance with an embodiment of the present invention. Pressurized hydrogen or other harmful gases are released to the atmosphere through the exhaust system after the heat treatment is complete. This schematic diagram shows two chambers 501 and 502, which are connected to exhaust pipes 503 and 504, respectively. The figure also shows an additional component part of the mixing tank 505, which is connected to an additional partition directly connected to the pipe. According to this specific embodiment, the gas from the first chamber 501 is mixed with the gas from the second chamber 502 in the mixing tank at the same time as it is released. If one of the gases is flammable, toxic and dangerous under high concentrations or high pressures, the mechanism dilutes the noxious gas with gas from another chamber. This is depicted in relation to, for example, the embodiment shown in FIGS. 2A and 2B. The mixed or diluted gas flows out of the mixing chamber 505 through another pipe 506, which may be connected to another mixing or dilution tank or combustion scrubber. In some embodiments, the exhaust pipes 503 and 504 may be very short or not provided at all, and the gas chamber may be connected directly to the mixing partition, thereby increasing the effectiveness of the mixing. In certain embodiments, exhaust valves (not shown) that open and close the exhaust pipe from the chamber are controlled together, and the relative amount of exhaust gas is automatically set based on their relative pressure. The exhaust gas may also depend on the relative size of each chamber and the relative size of the pipe diameter. In some other embodiments, the exhaust valves can be controlled independently so that the amount of gas in the exhaust gas from each chamber can be adjusted independently. In the latter case, the relative concentration of the exhaust gas can be controlled in the mixing tank 505 under conditions of high pressure.

According to at least one embodiment, another inert gas such as nitrogen is added during the exhaust process by reducing the concentration of the active gas from the heat treatment chamber. As shown in FIG. 7, in this specific embodiment, an extra gas pipe 507 is included in the mixing tank 505. Additive gases such as nitrogen reduce the concentration of more toxic or harmful gases such as hydrogen. This flow of additive gas also prevents backflow of gas from the outside through the exhaust pipe 506. As mentioned above, the backflow of the gas (back stream) or air from the outside can provide oxygen to the exhaust gas, for example, to have an adverse effect on the exhaust system. In some embodiments, the gas flow through the pipe 507 is automatically adjusted based on the gas amount or pressure of the exhaust gas from the exhaust pipe 503 and the exhaust pipe 504.

8 illustrates an exemplary process for venting exhaust gas from a two chamber heat treatment tube in accordance with an embodiment of the present invention. The tube comprises a first chamber and a second chamber as in the system shown in FIG. 7, and the first chamber is considered to contain the process gas that needs to be monitored for safety reasons. The flowchart shows the segment of the process after the heat treatment has been performed and the exhaust process has begun. In block S551, the control amount of gas from both chambers is released simultaneously or sequentially. As stated in the block, the pressure in each chamber needs to be monitored in order to ensure safety. For example, in the double wall chamber design shown in FIG. 3, the pressure differential needs to always be within a preset range. Then at block S552 the first gas concentration in the exhaust gas is measured or calculated. Here, the third preset value according to the present invention refers to a value that sets the ratio of the gas concentration coming out of the first chamber and the gas concentration coming out of the second chamber when the gas is discharged. If the first gas concentration is within the preset range, the exhaust process continues to the next block S555, as indicated by the yes path in block S553. On the one hand, an additional process, as indicated by the 'no' route, is carried out to convert the first gas concentration. For example, this can also be done by adding a gas amount (z amount) of inert gas into the mixing chamber, or controlling the amount of exhaust gas from each chamber in the next cycle of the process, as shown in block S554. If the gas is exhausted completely or the pressure level falls below a certain preset value, follow the 'yes' path of block S555, and this exemplary exhaust process stops at block S556.

After the process is completed or terminated, and after the gas has been depressurized, some residual gas may remain in the heat treatment chamber or any subsystem. The trapped residual gas eventually leaks and can interact with the air in the atmosphere, causing a potentially dangerous situation. There is also a high possibility that atmospheric air will be trapped inside the process chamber when the chamber door is closed, which can result in interaction with an active gas such as hydrogen when pressurization begins. According to at least one embodiment of the present invention, a nitrogen purifying process is employed at the start of the process after the chamber door is closed and before the start of hydrogen pressurization to remove residual gas or air trapped in various parts of the heat treatment apparatus. The nitrogen purge process can be used at the end of the process to purify hydrogen trapped in the gas chamber prior to opening the chamber door. In some embodiments, allowing nitrogen to flow at all times is maintained near the chamber or the exhaust valve of the heat treatment chamber to help remove residual gas remaining in the system after the process is complete.

As described above, a method and apparatus for heat treating a semiconductor device in a high pressure gas environment have been provided. Although the present invention has been described with reference to particular specific embodiments, it is evident that various changes and modifications can be made within the scope of the invention as set forth in these embodiments and claims without departing from the broader spirit. Accordingly, the foregoing description and drawings are to be regarded in an illustrative rather than a restrictive sense.

As described above, the present invention provides a method and apparatus for heat treatment of a semiconductor device in a high-pressure gas atmosphere, and a high-K gate insulating film heat treatment, a post-metallization sintering heat treatment, and The application of high pressure hydrogen / deuterium process for molding gas heat treatment has the effect of achieving a definite improvement in device performance.

In addition, the present invention can overcome a number of major stability problems associated with flammable and harmful gases such as high pressure hydrogen / deuterium, fluorine, ammonia, chlorine, and increase device lifetime, improve interconductance, and dangling bonds. There is an effect that can significantly improve the performance of the semiconductor device in various aspects such as reducing the bond).

In addition, the present invention has the effect of reducing the thermal history cost at a given process temperature and achieving a short processing time which is an essential requirement for improving device performance.

Claims (40)

An inner chamber made of a non-metallic material and designed to maintain a first pressure of a first gas containing at least one of hydrogen, deuterium, fluorine, chlorine and ammonia at a 100% net concentration; A high pressure heat treatment comprising: an outer chamber made of a metal material, the outer chamber including the inner chamber and designed to maintain a second gas pressure of a second gas including an inert gas outside of the inner chamber The device used for. The method of claim 1, And a holder connected to the inner chamber and configured to hold the semiconductor wafer in the inner chamber. The method of claim 1, Is connected to any one of the inner chamber and the outer chamber, And a heater configured to heat the first gas of the inner chamber. The method of claim 1, And said first gas pressure and said second gas pressure can be controlled separately. The method of claim 1, The inner chamber includes means for opening and closing the inner chamber, And said outer chamber comprises means for opening and closing said outer chamber. The method of claim 1, Wherein said non-metal material comprises quartz and said metal material comprises stainless steel. The method of claim 1, And means for discontinuing operation of the device for reducing at least one of said first gas pressure and said second gas pressure. delete The method of claim 1, wherein the first gas, A forming gas comprising deuterium, the forming gas comprising 1% to 99% deuterium. A method for processing an integrated circuit, A method for processing an integrated circuit comprising heat treating the integrated circuit in an atmosphere of deuterium gas at a pressure of at least 25 atm and a concentration of 1% to 99%. The method of claim 10, wherein the heat treatment atmosphere, A method for processing an integrated circuit comprising from 2% to 98% deuterium gas. In a method for protecting a first pressure chamber having a first gas at a first pressure, Providing a second pressure chamber surrounding the first pressure chamber; Adding a second gas to the second pressure chamber such that the pressure difference between the second pressure of the second gas and the first pressure of the first gas is essentially within a preset value range; Method for protecting the first pressure chamber with the first gas at the first pressure. The method of claim 12, And performing an emergency action if the pressure difference is outside of a preset value range. The method of claim 13, wherein the execution is A method for protecting a first pressure chamber with a first gas at a first pressure, characterized in that it comprises at least one of ringing an alarm or stopping the execution of the device. In a high pressure process chamber comprising an inner chamber and an outer chamber, the outer chamber includes an inner chamber, the inner chamber having the first gas at the first pressure and the outer chamber protecting the inner chamber with the second gas at the second pressure. In the method for Wherein the pressure difference between the first pressure and the second pressure essentially controls at least one of the amount of gas of the first gas in the inner chamber and the amount of gas of the second gas in the outer chamber within a preset value range. How to protect. The method of claim 15, And emergency action if the pressure difference is outside the preset value range. The method of claim 16, wherein the execution is At least one of ringing an alarm or stopping the execution of the device. At least one first chamber of the plurality of chambers comprises a first gas, at least one second chamber of the plurality of chambers comprises a second gas, Wherein at least one first chamber of the plurality of chambers is formed to enclose a second chamber of at least one of the plurality of chambers, The first chamber of at least one of the plurality of chambers converts the first pressure of the first gas, In order for the pressure difference between the converted pressure of the first chamber and the pressure of the second chamber to remain essentially within the preset value range, the second chamber of at least one of the plurality of chambers is the pressure of the second chamber of the second gas. Method for converting pressure in a plurality of pressure chambers characterized in that for converting. The method of claim 18, Adding a first gas into the first chamber of at least one of the plurality of chambers, At least one of evacuating a first gas from a first chamber of at least one of the plurality of chambers. The method of claim 18, Adding a second gas into a second chamber of at least one of the plurality of chambers, At least one of venting a second gas from a second chamber of at least one of the plurality of chambers. The method of claim 18, And emergency action if the pressure difference is outside the preset value range. A first exhaust pipe configured to carry a first gas from a first of the plurality of gas chambers; A second exhaust pipe configured to carry a second gas from a second one of the plurality of gas chambers; A third exhaust pipe connected to the first exhaust pipe and the second exhaust pipe; And Comprising: the partition connected to the first exhaust pipe and the second exhaust pipe and the third exhaust pipe; Wherein said first gas and said second gas are mixed in said partition, and said mixed gas is carried in said third exhaust pipe, said apparatus for discharging gas from a high pressure process chamber comprising a plurality of gas chambers. . The method of claim 22, wherein the third exhaust pipe, Apparatus for evacuating gas from a high pressure process chamber comprising a plurality of gas chambers, characterized in that it is configured to carry gas mixed out of the apparatus. The method of claim 22, The volume ratio between the second chamber and the first chamber is higher than the first preset value set so that the volume of the second chamber is larger, The pressure ratio between the second gas in the second chamber and the first gas in the first chamber is lower than a third preset value set such that the concentration of the first gas in the mixed gas is greater. And during the high pressure process, the pressure of the second chamber is higher than a second preset value set to be greater. The method of claim 22, A combustion scrubber connected to the third exhaust pipe; And a fourth exhaust pipe connected to said combustion scrubber and used to flow said mixed gas out of said device. 2. The apparatus of claim 1, further comprising a plurality of gas chambers. The method of claim 22, And a gas pipe connected to the partition and configured to flow a third gas into the third exhaust pipe. 2. The apparatus of claim 1, further comprising a gas pipe. The method of claim 26, wherein the gas pipe, Apparatus for discharging gas from the high pressure process chamber comprising a plurality of gas chambers characterized in that the flow of the third gas is adjusted in accordance with the gas flow of at least one of the first exhaust pipe and the second exhaust pipe. The method of claim 26, The flow of the third gas in the gas conduit is maintained so that there is a gas flow outward to the third exhaust pipe towards the outside of the device, so that the flow of air from the outside of the device in the third exhaust pipe is essentially reduced. Apparatus for discharging gas from a high pressure process chamber comprising a plurality of gas chambers, characterized in that. A first chamber made of non-metallic material and designed to maintain the first pressure of the first gas, and containing the first chamber made of metal material and maintaining the second gas pressure of the second gas outside of the first chamber A method for evacuating a gas from a plurality of gas chambers, including a second chamber designed to Exhausting the first gas from the plurality of chambers in the first chamber to the mixing tank through the first exhaust pipe; The second gas in the second chamber from the plurality of chambers such that the ratio between the amount of gas of the first gas exhausted in a given period and the amount of gas of the second gas in a given period is maintained from above the first preset value to below the second preset value And exhausting the mixed tank through a second exhaust pipe to the mixing tank. The method of claim 29, Adding a third gas to the mixing tank during at least one of the exhausting operation of the first gas and the exhausting operation of the second gas; Way. A first chamber designed to maintain the first gas pressure of the first gas; A second chamber connected to the first chamber such that the first gas is surrounded by a second gas and designed to maintain a second gas pressure of the second gas; A first injection tube formed to carry the first gas and connected to the first chamber; And And a second injection tube formed to carry the second gas and connected to the second chamber. The method of claim 31, wherein First means for opening and closing the first chamber; The second means for opening and closing the second chamber; apparatus for high pressure heat treatment, characterized in that it further comprises. The method of claim 32, At least one of the first means for opening and closing, and the second means, wherein the inlet gas is a gas inlet means which is an inert gas. The method of claim 31, wherein The first injection tube comprises a double walled stainless steel pipe, and the second injection tube comprises a double walled stainless steel pipe. The first gas chamber comprises a first gas chamber and a second gas chamber formed to surround the second gas chamber, the first gas chamber being formed to contain the first gas, and the second gas chamber being A tube formed to contain a second gas; An inlet gas flow control system comprising a first gas pipe and a second gas pipe connected to the pipe, wherein the first gas pipe is connected to the first gas chamber and the second gas pipe is connected to the second gas chamber; And A first exhaust pipe, a second exhaust pipe and a third exhaust pipe, wherein the first exhaust pipe is connected to the first gas chamber, the second exhaust pipe is connected to the second gas chamber, and the third exhaust pipe is connected to the first exhaust pipe. And a gas exhaust system connected to the pipe so as to be connected to a second exhaust pipe and a second exhaust pipe. The method of claim 35, wherein the inflow gas flow control system, A valve for opening and closing the gas flow; At least one of the valve, the first gas pipe, and the second gas pipe is protected by a double wall structure. The method of claim 35, wherein the inflow gas flow control system, And a gas control cabinet connected to at least one of the first gas pipe and the second gas pipe. delete 36. The method of claim 35 wherein And a holder formed to hold the semiconductor wafer in the first gas chamber, the holder being associated with the first gas chamber. 36. The method of claim 35 wherein And a heater formed to heat the first gas inside the first gas chamber, the heater being associated with at least one of the first gas chamber and the second gas chamber. Apparatus for heat treatment of the device.

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