CN119221111A - A method for controlling metal content in an epitaxial furnace cavity - Google Patents
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- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 45
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- 239000011261 inert gas Substances 0.000 claims description 9
- ZDHXKXAHOVTTAH-UHFFFAOYSA-N trichlorosilane Chemical compound Cl[SiH](Cl)Cl ZDHXKXAHOVTTAH-UHFFFAOYSA-N 0.000 claims description 9
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Abstract
The invention relates to a metal content control method of an epitaxial furnace cavity, which comprises the following steps of cleaning, removing residual substances in the cavity, introducing gas into the cavity to remove dust and impurity residues, then heating an element to remove organic matters and moisture on the surface of a substrate, keeping the temperature and pressure in the cavity stable after the steps are completed, finally removing the residual substances on the surface of the substrate in an etching step, growing a silicon layer with controllable thickness on the surface of a substrate, introducing gas into the cavity to remove the residual substances, keeping the temperature and pressure in the cavity stable after the steps are completed, finally enabling the surface of the substrate to generate a silicon layer with controllable thickness in the coating step, and cooling to ensure the temperature of the cavity to be 25 ℃, introducing gas into the cavity to remove the residual substances, and then reducing the temperature of the substrate to 25 ℃. The problem of metal exceeding of the epitaxial wafer is solved by optimizing the etching step and the coating step, so that the quality of the epitaxial wafer is improved.
Description
Technical Field
The invention relates to the technical field of semiconductor manufacturing, in particular to a metal content control method of an epitaxial furnace cavity.
Background
The epitaxial furnace utilizes the reduction reaction of trichlorosilane or silicon chloride and the like with hydrogen to grow monocrystal epitaxy on a monocrystal substrate silicon wafer, along with the increase of the number of produced epitaxial wafers, a reaction chamber of the epitaxial furnace needs to be shut down, cleaned and maintained, and metal pollutants are introduced from the outside in the process of replacing accessories, so that the content of the metal pollutants in an epitaxial furnace chamber is increased, the quality of the epitaxial wafers is reduced even if the concentration is low, and finally the performance of devices is reduced. In the prior art, the cleaning method of the reaction cavity is mainly to introduce hydrogen chloride gas into the cavity, etch the residual silicon oxide in the cavity and then discharge the silicon oxide through tail gas treatment, thereby improving the environment in the cavity.
The traditional cleaning method has poor effect of improving the metal content, and can not remove the residual metal impurities on the surface of the substrate, so that the metal impurities infiltrate into the epitaxial wafer, and the metal of the epitaxial wafer exceeds the standard, thereby reducing the quality of the epitaxial wafer and further adversely affecting the performance of components.
Disclosure of Invention
The invention aims to solve the problems in the prior art, and provides a metal content control method for an epitaxial furnace cavity, which improves the problem of exceeding the standard of epitaxial wafer metal by optimizing an etching process and a coating process in a scheme, thereby improving the quality of epitaxial wafers.
The invention solves the technical problems by adopting a technical method that the metal content control method of an epitaxial furnace cavity comprises the following steps:
S100, cleaning in a first stage to remove residual substances in a cavity, firstly introducing gas into the cavity to remove dust and impurity residues, then gradually raising the temperature of a heating element to a certain temperature for removing organic matters and moisture on the surface of the substrate, and removing the residual substances on the surface of the substrate by using etching gas after the organic matters and moisture on the surface of the substrate are completely evaporated;
s200, coating in a second stage, namely growing a silicon layer with controllable thickness on the surface of the base, firstly introducing gas into the cavity to remove surface residual substances, then monitoring the temperature and the pressure by using a temperature and pressure detection device to ensure the stability of the temperature and the pressure in the cavity, and then coating by using reaction gas to enable the surface of the base to generate the silicon layer with controllable thickness;
s300, cooling in the third stage to ensure that the temperature of the cavity is 25 ℃, introducing gas into the cavity to remove surface residual substances, and then reducing the temperature of the substrate to 25 ℃.
In the scheme, residual substances on the surface of the substrate can be effectively removed through first-stage cleaning, and then a silicon layer with controllable thickness is formed on the surface of the substrate through second-stage coating, so that the silicon layer has a stable structure and good adhesion with metal materials, and metal pollutants attached to the surface of the substrate are reduced from diffusing outwards.
Preferably, the first stage cleaning specifically includes the following steps:
s110, purging, namely using inert gas as cleaning gas, moving and cleaning through a nozzle to ensure that no visible dust and impurity remain in the cavity, and then checking the inner surface of the cavity by using an optical microscope to confirm that no particles remain;
S120, raising the temperature, namely gradually raising the temperature from room temperature to 1000 ℃ through a heating element, wherein uniform temperature distribution is ensured in the whole process;
S130, baking, namely when the temperature is gradually increased to 1000 ℃, then keeping constant-temperature baking, and when the surface of the substrate presents a dry state after organic matters and moisture are completely evaporated, detecting the surface of the substrate by using a detection device, and confirming that no organic matters and moisture remain;
s140, stabilizing, namely after baking is finished, keeping the temperature and the pressure in the epitaxial cavity stable, and monitoring the temperature and the pressure by using a temperature and pressure monitoring device to ensure the stability of the environmental conditions in the cavity;
S150, etching by using etching gas, and checking the surface of the substrate by using a microscope to confirm
No residual substances.
In the stage, dust and impurities on the surface are removed by blowing the cavity of the epitaxial furnace, organic matters and moisture on the surface of the substrate are removed by high-temperature baking treatment, residual matters can be effectively removed by etching gas, and stable treatment on the temperature and pressure in the cavity is also carried out after the baking treatment, so that proper environmental conditions are provided for realizing the etching step.
Preferably, the etching step is performed for 36s to 53s, and the etching time is prolonged, so that residual substances on the surface of the base can be thoroughly removed.
Preferably, the gas used in the etching step is hydrogen chloride, and the etching rate is 0.25 μm/s, so that the residual substances on the surface of the base can be effectively removed.
Preferably, the second stage coating specifically comprises the following steps:
s210, purging, namely using inert gas as cleaning gas, moving and cleaning through a nozzle to ensure that no visible dust and impurity remain in the cavity, and then checking the inner surface of the cavity by using an optical microscope to confirm that no particles remain;
s220, stabilizing, namely keeping the temperature and the pressure in the epitaxial cavity stable, and monitoring the temperature and the pressure by using a temperature and pressure monitoring device to ensure the stability of the environmental conditions in the cavity;
s230, coating by using reaction gas, so that a silicon layer with controllable thickness grows on the surface of the base, and measuring the thickness of the silicon layer by using a thickness measuring device to ensure uniformity and thickness control.
In the stage, the interior of the epitaxial furnace chamber is purged to remove residues on the surface, the temperature and the pressure in the chamber are stabilized to create good environmental conditions for the subsequent coating step, and in addition, the silicon layer with controllable thickness grown on the surface of the base in the coating step plays a role of a protective film and can effectively block the diffusion of metal pollutants to the epitaxial wafer.
Preferably, the thickness of the silicon layer in the coating step is 1-2 μm. The thickness of the silicon layer is increased, so that the influence of metal pollutants on the epitaxial wafer can be reduced, but the silicon layer is too thick, the pins of the base and the external support base are adhered together, and the thickness of the silicon layer is controlled to be 1-2 mu m after the advantages and disadvantages of the base and the external support base are combined.
Preferably, the reaction gases used in the coating step are trichlorosilane and hydrogen, so that a silicon layer with controllable thickness grows on the surface of the base, and the silicon layer plays a role of a protective film.
Preferably, the time of the coating step is 45s to 125s, so that the time of the coating step is prolonged, the thickness of the silicon layer on the surface of the substrate can be increased, and further, the diffusion of metal pollutants on the surface of the substrate to the epitaxial layer can be effectively prevented.
Preferably, argon is introduced as a carrier in the coating step, and the argon accounts for 10 to 30 percent of the total gas flow, so that the coating step is further optimized, and the uniformity and thickness control of the protective film are ensured.
Preferably, the third stage cooling specifically includes the following steps:
s310, purging, namely using inert gas as cleaning gas, moving and cleaning through a nozzle to ensure that no visible dust and impurity remain in the cavity, and then checking the inner surface of the cavity by using an optical microscope to confirm that no particles remain;
And S320, cooling, namely firstly cooling the substrate to room temperature, and monitoring the temperature by using a temperature monitoring device to ensure that the temperature is stabilized to 25 ℃.
After the first-stage cleaning and the second-stage coating are completed, the epitaxial furnace chamber is still in a high-temperature state, so that the main purpose of the stage is to cool down.
The invention has the following beneficial effects:
1. Through multistage cleaning, coating and cooling steps, the metal content of the epitaxial wafer is effectively reduced, the purity and quality of the epitaxial wafer are improved, the service life of the epitaxial wafer is prolonged, the performance and reliability of the epitaxial wafer are improved, and the method is suitable for manufacturing high-performance semiconductor devices.
2. Through cleaning steps including purging, heating, baking, stabilizing and etching, dust, impurities, organic matters and moisture in the cavity and residual substances on the surface of the substrate are thoroughly removed, the cleanliness of the cavity is ensured, a pure environment is provided for subsequent epitaxial growth, and the pollution risk of the epitaxial wafer is reduced.
3. In the etching step, hydrogen chloride gas is used for etching, the etching time is prolonged to a preset time, the residual substances on the surface of the substrate are thoroughly removed, no residual substances on the surface of the substrate are confirmed, the cleanliness of the surface of the substrate is improved, and a high-quality substrate is provided for subsequent epitaxial growth.
4. In the coating step, a silicon layer with the thickness of 1-2 mu m is generated on the surface of a base through blowing, stabilizing and coating, trichlorosilane and hydrogen are used as reaction gases, the coating time is prolonged to a preset time, uniform growth and thickness control of the silicon layer are ensured, in addition, argon is introduced as a carrier, the transmission efficiency of the reaction gases is further improved, uniformity and thickness control of the silicon layer are ensured, diffusion of metal pollutants on the surface of a substrate to an epitaxial layer is effectively prevented, the temperature of the substrate is reduced to a preset temperature through a cooling step, stability of the temperature of a cavity is ensured, a reliable environment is provided for a subsequent process, and the quality and reliability of an epitaxial wafer are improved.
Drawings
FIG. 1 is a flow chart of an embodiment of the present invention;
FIG. 2 is a graph showing the results of a cavity preventative maintenance post-bulk metal test in accordance with the present invention;
FIG. 3 shows the results of a cavity metal test after 60s coating in the present invention.
Detailed Description
The invention is further described with reference to fig. 1 to 3 of the accompanying drawings:
referring to fig. 1, the present invention provides a method for controlling the metal content of an epitaxial furnace chamber, which is divided into three stages as a whole, cleaning, coating and cooling.
S100, cleaning in the first stage, and removing residual substances in the cavity. The method comprises the steps of firstly introducing inert gas into a cavity to remove dust and magazine residues, checking the inner surface of the cavity by using an optical microscope after the completion of the process, confirming that no residues exist, then gradually raising the temperature of a heating element to a certain temperature for removing organic matters and moisture on the surface of a substrate, detecting the surface of the substrate by using a detection device after the organic matters and moisture on the surface of the substrate are completely evaporated, confirming that no organic matters and moisture remain, then monitoring the temperature and the pressure by using a temperature and pressure detection device to ensure the stability of the temperature and the pressure in the cavity, finally removing the residues on the surface of a base by using etching gas, and checking the surface of the base by using the microscope to ensure that no residues exist.
In this embodiment, the heating element may be configured as a resistive wire or an infrared lamp to control the temperature during the cleaning process, thereby achieving precise temperature rise or baking.
The cleaning of residual substances in the cavity ensures the cleanness of the interior of the epitaxial furnace cavity, and provides a good foundation for subsequent epitaxial growth. In addition, the etching in the stage can effectively remove residual substances on the surface of the base, ensure the cleaning of the surface of the base and reduce the influence of the residual substances on the subsequent process.
And S200, coating in the second stage, and growing a silicon layer with controllable thickness on the surface of the base. The method comprises the steps of firstly introducing inert gas into a cavity to remove dust and magazine residues, checking the inner surface of the cavity by using an optical microscope after the completion of the process, confirming no residual particles, then monitoring the temperature and the pressure by using a temperature and pressure detection device to ensure the stability of the temperature and the pressure in the cavity, then coating by using reaction gas to enable the surface of a base to generate a silicon layer with controllable thickness, and measuring the thickness of the silicon layer by using a thickness measurement device to ensure the uniformity and the thickness of the silicon layer to be controllable.
In this stage, a silicon layer with controllable thickness grows on the surface of the base, and the silicon plays a role of a protective film, so that diffusion of metal pollutants to the epitaxial wafer can be prevented.
S300, cooling in the third stage, and ensuring the temperature of the cavity to be 25 ℃. Firstly, introducing inert gas into the cavity to remove dust and magazine residues, checking the inner surface of the cavity by using an optical microscope after the completion of the removal, confirming that no residual particles exist, then cooling the substrate to room temperature, and monitoring the temperature by using a temperature monitoring device to ensure that the temperature is reduced to 25 ℃.
After removing the metal residual substances in the cavity, the temperature in the cavity is still in a high-temperature state, so that the main effect of the stage is to cool down.
To further illustrate the effect achieved by the first stage cleaning, a further description is therefore made of the first stage cleaning. The specific steps for realizing the first-stage cleaning comprise:
S110, purging, namely using high-purity nitrogen as cleaning gas, and moving and cleaning the chamber in a large-angle circumferential swinging mode through a nozzle to ensure that no visible dust and impurities remain in the chamber. At this time, the swing angle of the nozzle is 120 degrees, the swing frequency is 1Hz, the nozzle is 10cm away from the epitaxial cavity wall, the gas flow is 500-1000sccm, and the air flow speed in the epitaxial cavity is 1-2m/s by purging. The time for the entire purging process was 5s, after which the interior surfaces of the chamber were inspected using an optical microscope to confirm that no particles remained. In the step, dust and impurities on the surface of the cavity can be effectively removed by blowing the epitaxial furnace cavity.
And S120, heating by an infrared lamp to enable the temperature in the cavity to rise at a rate of 10 ℃ per second, and gradually raising the temperature in the cavity from room temperature (about 25 ℃) to 1000 ℃. The duration of the whole temperature rising process is 30s, and in the process, the uniform temperature distribution is ensured, and the local overheating is avoided. To ensure that the temperature deviation does not exceed + -5 deg.c, the temperature within the cavity is monitored using a thermocouple. In this step, the main purpose of the temperature increase is to make the temperature in the epitaxial furnace chamber reach the requirements required by the subsequent process environment.
And S130, baking, namely stopping heating and keeping the temperature at 1000 ℃ when the temperature rises to 1000 ℃, and keeping the constant temperature in the cavity for 45 seconds for baking in order to remove organic matters and moisture on the surface of the substrate. And detecting the surface of the substrate by using an infrared spectrometer when the surface of the substrate is in a dry state after the organic matters and the moisture on the surface of the substrate are completely evaporated, and confirming that no organic matters and moisture remain.
And S140, stabilizing, namely keeping the temperature and pressure in the cavity stable after baking, wherein the duration of the stabilizing process is 10S, so that the environmental conditions in the cavity are suitable for the subsequent etching steps. To ensure that the temperature and pressure do not fluctuate by more than + -1% over the set point, thermocouples and pressure sensors are used to monitor the temperature and pressure within the cavity.
And S150, etching by using hydrogen chloride gas, wherein the time of the whole etching process is 43S, the gas flow in the etching process is 1000sccm, the etching rate is 0.25 mu m/S, and the etching temperature is 1000 ℃. During this process, residual material (e.g., oxides, metal particles, etc.) on the susceptor surface will be thoroughly removed, and scanning electron microscopy is used to examine the susceptor surface to confirm the absence of residual material.
In this step, hydrogen chloride gas is used as an etching gas, and the etching rate is controlled to be 0.25 μm/s, so that the residual substances on the surface of the susceptor can be effectively removed. The etching time is optimized and controlled at 43s, so that residual substances on the surface of the base can be thoroughly removed, and the surface of the base cannot be corroded due to overlong etching time, thereby damaging equipment and products. The optimization of the etching step effectively removes residual substances on the surface of the base, reduces metal pollution and improves the quality and purity of the epitaxial wafer.
To further illustrate the effect achieved by the second-stage coating, therefore, a further description of the second-stage coating is made, with the specific steps of achieving the second-stage coating including:
S210, purging, namely using high-purity nitrogen as cleaning gas, and moving and cleaning the cleaning gas in a mode of large-angle circumferential oscillation through a nozzle to ensure that no visible dust and impurities remain in the cavity. At this time, the swing angle of the nozzle is 120 degrees, the swing frequency is 1Hz, the nozzle is 10cm away from the epitaxial cavity wall, the gas flow is 500-1000sccm, and the air flow speed in the epitaxial cavity is 1-2m/s by purging. The time for the entire purging process was 30s, after which the interior surfaces of the chamber were inspected using an optical microscope to confirm that no particles remained. In the step, the residual on the surface of the cavity can be effectively removed by purging the cavity of the epitaxial furnace.
S220, stabilizing, namely keeping the temperature and pressure in the cavity stable after baking, wherein the duration of the stabilizing process is 15S, so that the environmental conditions in the cavity are suitable for the subsequent coating steps. To ensure that the temperature and pressure do not fluctuate by more than + -1% over the set point, thermocouples and pressure sensors are used to monitor the temperature and pressure within the cavity.
S230, coating is carried out by using trichlorosilane and hydrogen, so that a silicon layer with controllable thickness grows on the surface of the base, the silicon layer plays a role of a protective film, and diffusion of metal pollutants to the epitaxial wafer can be effectively prevented. The time of the whole coating process is 60s, the flow rate of trichlorosilane is 100-500sccm, the flow rate of hydrogen is 1000-5000sccm, and the coating temperature is 1000 ℃. Precise control of the gas flow and reaction time should be ensured during the coating process to produce a uniform and thickness-controllable silicon layer. The thickness of the silicon layer should be controlled to be 1-2 μm, and during this process, it is necessary to measure the thickness of the silicon layer using an ellipsometer to ensure uniformity and thickness control thereof.
In this step, silicon gas trichloride is used to react with hydrogen to form silicon. The trichlorosilane and the hydrogen gas generate chemical vapor deposition reaction at high temperature, and a silicon layer with uniform thickness and controllable thickness can be formed on the surface of the base. Trichlorosilane is a common silicon source gas, has higher reactivity, and can decompose and release silicon atoms at high temperature to react with hydrogen to generate a silicon layer. The hydrogen is used as a reducing agent, so that the decomposition of trichlorosilane can be promoted, the growth rate and quality of a silicon layer can be improved, meanwhile, the hydrogen can also remove oxides on the surface of a substrate, and the purity and uniformity of the silicon layer can be ensured.
In addition, proper amount of argon is introduced as a carrier in the coating step, so that the uniformity and controllability of the coating process are improved, the thickness consistency of the protective film is ensured, and the total proportion of the argon in the total airflow is 10% -30%.
TABLE 1
As shown in fig. 2 and 3, the test value of the bulk metal after the preventive maintenance of the cavity is 2.68e12, and the content of the bulk metal in the cavity is required to be less than 5e10, so that the content of the bulk metal is seriously out of standard. Comparing the content of the bulk metal in the chamber at different coating times in table 1, it can be concluded that the longer the coating time, the lower the content of the bulk metal in the chamber. However, too long a coating time can cause the pins of the base and the outer support base to adhere together, affecting the service life of the chamber, and therefore the coating time needs to be controlled within a reasonable range. After the experiment, the time of the coating step is determined to be optimized, and finally the time of the coating stage is controlled to be 60s, on the one hand, the optimizing scheme effectively blocks the diffusion of metal pollutants to the epitaxial wafer, on the other hand, the adhesion between the base and the pin of the external supporting base is avoided, and the reliability and stability of the process are improved.
Argon is introduced as a carrier, uniformity and controllability of a coating process are improved, the thickness consistency of a protective film is ensured, diffusion of metal pollutants is effectively blocked, the structure of an epitaxial wafer is further improved through annealing treatment, stress is eliminated, crystallization quality and electrical property of an epitaxial layer are improved, the metal content of the epitaxial wafer is further reduced through optimization measures, the purity and reliability of the epitaxial wafer are improved, and the manufacturing requirement of a high-performance semiconductor device is met.
In Table 2 below, S1, purging, 5 seconds, the step of removing dust and impurities on the surface by purging the epitaxial furnace chamber, S2, heating, 30 seconds, the step of heating the substrate to a certain temperature, preparing for the subsequent process, S3, baking, 45 seconds, removing organic matters and moisture on the surface of the substrate by high-temperature treatment, S4, stabilizing, 10 seconds, the step of ensuring the substrate temperature to be stable, providing stable conditions for the subsequent process, S5, etching, 36 seconds to 53 seconds, removing residual matters on the surface of the substrate by chemical gas, S6, purging, 30 seconds, re-purging the epitaxial furnace chamber, removing the residual matters on the surface, S7, stabilizing, 15 seconds, ensuring the substrate temperature to be stable, providing stable conditions for the subsequent process, S8, coating, 45 seconds to 125 seconds, acting as a protective film on the surface of the substrate, effectively blocking metal pollution, S9, 15 seconds, re-purging the furnace chamber, removing the residual matters on the surface, cooling, and cooling the substrate to be 5 seconds, and preparing for purging the substrate.
TABLE 2
In the following table 3, the time of the coating step is 60 seconds to balance the metal content control and avoid the adhesion of the pins of the base and the external support base, and by optimizing the coating time, the moderate thickness of the protective film is ensured, thereby not only effectively blocking the metal pollution, but also avoiding the adhesion of the pins of the base and the external support base, and improving the reliability and stability of the process, and the time of the etching step is 43 seconds to ensure the removal of the residual substances on the base, and by precisely controlling the etching time, the thorough removal of the residual substances on the surface of the base is ensured, and the purity and quality of the epitaxial wafer are improved.
TABLE 3 Table 3
To further illustrate the effect achieved by the third stage cooling, therefore, a further description of the third stage cooling is provided, with the specific steps of achieving the third stage cooling including:
S310, purging, namely using high-purity nitrogen as cleaning gas, and moving and cleaning the chamber in a large-angle circumferential swinging mode through a nozzle to ensure that no visible dust and impurities remain in the chamber. At this time, the swing angle of the nozzle is 120 degrees, the swing frequency is 1Hz, the nozzle is 10cm away from the epitaxial cavity wall, the gas flow is 500-1000sccm, and the air flow speed in the epitaxial cavity is 1-2m/s by purging. The time for the entire purging process was 15s, after which the interior surfaces of the chamber were inspected using an optical microscope to confirm that no particles remained. In the step, the residual on the surface of the cavity can be effectively removed by purging the cavity of the epitaxial furnace.
S320, cooling, namely, rapidly cooling the temperature in the cavity to room temperature by taking nitrogen as atmosphere protection, wherein the time of the whole cooling process is 5S, and the gas flow is 1000sccm. In order to avoid stress due to temperature gradients, thermocouples were used to detect the temperature.
In order to further describe the technical means and effects adopted by the present invention for achieving the intended purpose, the following detailed description will refer to the specific implementation, structure, characteristics and effects according to the present invention with reference to the accompanying drawings and preferred embodiments.
The present invention is not limited in any way by the above-described preferred embodiments, but is not limited to the above-described preferred embodiments, and any person skilled in the art will appreciate that the present invention can be embodied in the form of a program for carrying out the method of the present invention, while the above disclosure is directed to equivalent embodiments capable of being modified or altered in some ways, it is apparent that any modifications, equivalent variations and alterations made to the above embodiments according to the technical principles of the present invention fall within the scope of the present invention.
Claims (10)
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| CN202411770221.7A CN119221111A (en) | 2024-12-04 | 2024-12-04 | A method for controlling metal content in an epitaxial furnace cavity |
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| US6277194B1 (en) * | 1999-10-21 | 2001-08-21 | Applied Materials, Inc. | Method for in-situ cleaning of surfaces in a substrate processing chamber |
| JP2006196910A (en) * | 2005-01-14 | 2006-07-27 | Samsung Electronics Co Ltd | In-situ cleaning method for semiconductor substrate, and manufacturing method of semiconductor element adopting the same |
| KR101525966B1 (en) * | 2015-02-10 | 2015-06-05 | 홍진석 | Method for cleaning gas laser apparatus |
| WO2017122963A2 (en) * | 2016-01-12 | 2017-07-20 | 주식회사 엘지실트론 | Method for manufacturing epitaxial wafer |
| US20190093215A1 (en) * | 2015-07-28 | 2019-03-28 | Sk Siltron Co., Ltd. | Method of preparing for reactor restart for manufacturing epitaxial wafer |
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| US6277194B1 (en) * | 1999-10-21 | 2001-08-21 | Applied Materials, Inc. | Method for in-situ cleaning of surfaces in a substrate processing chamber |
| JP2006196910A (en) * | 2005-01-14 | 2006-07-27 | Samsung Electronics Co Ltd | In-situ cleaning method for semiconductor substrate, and manufacturing method of semiconductor element adopting the same |
| KR101525966B1 (en) * | 2015-02-10 | 2015-06-05 | 홍진석 | Method for cleaning gas laser apparatus |
| US20190093215A1 (en) * | 2015-07-28 | 2019-03-28 | Sk Siltron Co., Ltd. | Method of preparing for reactor restart for manufacturing epitaxial wafer |
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| 李明达等: "快速恢复外延二极管用150mm高均匀性硅外延材料的制备", 固体电子学研究与进展, no. 05, 25 October 2017 (2017-10-25), pages 72 - 80 * |
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