Apparatus constructed and arranged to process plurality of substrates

Abstract

An apparatus 1 for processing a plurality of substrates 3 is provided. The apparatus may have a process tube 5 forming a process chamber 7 and a door 15 configured to support a substrate 3 in the process chamber and seal the process chamber 7. The apparatus may have a gas injector 23 to provide a process gas into the process chamber. The gas injector may be operably connected to a process gas line 27 in the purge chamber 9 to purge a connection between the gas injector 23 and the process gas line 27.

Description

Technical Field

[0001] The present disclosure relates to an apparatus constructed and arranged to process a plurality of substrates. More specifically, the present disclosure relates to an apparatus comprising:

[0002] a process tube forming a process chamber;

[0003] a gas injector for providing process gas into the process chamber; and

[0004] A door is configured to support a wafer boat having a plurality of substrates in a processing chamber. Background Art

[0005] Semiconductor substrates can be processed in batches in a vertical furnace. An example of such a process is the reaction of various material layers on the substrate at high temperature in a process chamber. A process tube forming the process chamber can be provided with, for example, hydrogen as a process gas.

[0006] The apparatus may include a gas injector for providing a process gas into the process chamber. The gas injector may be operably connected to a process gas line. The connection between the gas injector and the process gas line may create a risk of hydrogen leakage. Oxygen may react with the leaking hydrogen, creating a safety risk. Summary of the invention

[0007] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the detailed description of the example embodiments disclosed below. This summary is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0008] The aim is to provide a device in which the risk of hydrogen reacting with oxygen can be minimised.

[0009] According to one aspect, an apparatus constructed and arranged to process a plurality of substrates may be provided. The apparatus may have a process tube forming a process chamber and a gas injector for providing a process gas into the process chamber. A door configured to support a wafer boat having a plurality of substrates in the process chamber and to seal the process chamber may be provided. The gas injector may be operably connected to a process gas line. A purge chamber connected to an inert gas source may be provided. The gas injector may be operably connected to a process gas line in the purge chamber to purge a connection between the gas injector and the process gas line.

[0010] In order to summarize the present invention and the advantages achieved relative to the prior art, certain objects and advantages of the present invention have been described above. Of course, it should be understood that not all of these objects or advantages may be achieved according to any particular embodiment of the present invention. Thus, for example, those skilled in the art will recognize that the present invention may be implemented or performed in a manner that achieves or optimizes one advantage or a group of advantages taught or suggested herein without having to achieve other objects or advantages taught or suggested herein.

[0011] All of these embodiments are within the scope of the invention disclosed herein. These and other embodiments will become apparent to those skilled in the art from the following detailed description of certain embodiments with reference to the accompanying drawings, the invention not being limited to any particular embodiment disclosed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] While the specification concludes with claims that particularly point out and distinctly claim what are considered to be the embodiments, advantages of the embodiments of the present disclosure may be more readily ascertained from the description of certain examples of the embodiments of the present disclosure when read in conjunction with the accompanying drawings, in which:

[0013] Figure 1a is a schematic cross-sectional side view of an apparatus for processing a plurality of substrates in a closed state according to an embodiment of the present invention;

[0014] Figure 1b is another schematic cross-sectional side view of an apparatus for processing a plurality of substrates in a closed state according to an embodiment of the present invention;

[0015] Figure 2 is a schematic diagram of a dilution gas flow line that may be included in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] Although certain embodiments and examples are disclosed below, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments and / or uses of the present invention and obvious modifications and equivalents thereof. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specifically disclosed embodiments described below. The illustrations presented herein are not meant to be actual views of any particular material, structure, or device, but are merely idealized representations used to describe embodiments of the present disclosure.

[0017] As used herein, the term "substrate" or "wafer" may refer to any one or more underlying materials that may be used or on which a device, circuit, or film may be formed. The term "semiconductor device structure" may refer to any portion of a processed or partially processed semiconductor structure that includes or defines at least a portion of an active or passive element of a semiconductor device to be formed on or in a semiconductor substrate.

[0018] Semiconductor substrates can be processed in batches. Figure 1a and Figure 1b A portion of an exemplary batch reactor is schematically illustrated. The reactor illustrated may be a vertical furnace type reactor, which facilitates efficient heating and loading.

[0019] Figure 1a and Figure 1b A schematic cross-sectional side view of a process tube 5 of an apparatus 1 for processing a plurality of substrates 3, such as a vertical furnace in a closed state, is shown. The apparatus may have a process tube 5 forming a process chamber 7. The process tube 5 may be open at the bottom and closed at the top in a dome shape (not shown).

[0020] Optionally, a purge chamber 9 may be provided around the process tube 5 for purging the outside of the process tube 5. The purge chamber 9 may be connected to an inert gas source via a purge line 10 to purge the outside of the process tube 5. The purge line 10 may be connected to a tank or an inert gas line from a plant using the apparatus 1 as an inert gas source.

[0021] The susceptor 8 may support a wafer boat 17 that holds a plurality of wafers 3, preferably between 50 and 200 wafers, in the process chamber 7. The susceptor 8 may be thermally insulated to prevent overheating of the surrounding portion of the vertical furnace including the door 15 that supports the susceptor 8. The interior of the door 15 may also be purged. This may be done with nitrogen.

[0022] The process tube 5 may have a base that may be supported on a flange 11. A seal may be provided between the process tube 5 and the flange 11 to close the process chamber. An additional flange 11 may be used to surround and / or support the process tube 5 to seal it. The flange 11 may also be used to support other components in the process tube, such as a syringe or liner. The flange 11 for supporting the process tube 5 may be provided with a flange opening 13 leading to the opening of the process tube 5.

[0023] The wafer boat 17 with the substrates 3 can be moved into the process chamber 7 through the flange opening 13 while being supported on the door 15. At the end of the movement, the door 15 can seal the process chamber 7 while supporting the wafer boat 17 with the plurality of substrates 3 in the process chamber. The apparatus can have an exhaust port operably connected to the process chamber 7 to remove gas from the process chamber through a process gas exhaust conduit 19. The process gas exhaust conduit 19 can be connected to the process chamber 7 through a hole in the flange 11.

[0024] The purge chamber 9 may extend to partially surround the flange 11. The purge chamber 9 may also partially surround the process gas exhaust conduit 19 at least where the process gas exhaust conduit 19 connects to the process chamber 7. In other words, the connection between the process gas exhaust conduit 19 and the process chamber 7 may be at least partially surrounded by the purge chamber 9 to allow the connection between the process gas exhaust conduit 19 and the process chamber to be purged. The purge chamber 9 may be connected to a purge exhaust conduit 23 to remove gas from the purge chamber 21. In this way, any process gas that may leak from the process chamber 7, the purge chamber 9, or the process gas exhaust conduit 19 at the connection with the process chamber 7 may be pumped away with the purge pump 53.

[0025] refer to Figure 2 In some embodiments, the process gas exhaust conduit 19 can be connected to the dilution gas line 70 via an injection tube 71 for injecting gas from the process gas exhaust conduit 19 into the dilution gas flow in the dilution gas line 70 at an injection point P. The dilution gas line 70 can be configured to provide a dilution gas flow that can be air. The dilution gas line can provide a high flow of dilution gas, such as at least 1500 standard liters per minute (slm). The dilution gas line 70 can include a nitrogen injection nozzle 72 for injecting nitrogen into the dilution gas flow. The nitrogen injection nozzle 72 can be disposed upstream of the injection point P. The nitrogen injection nozzle 72 can provide a nitrogen flow rate of at least 60 slm or at least 70 slm to the dilution gas flow. The nitrogen flow promotes turbulent mixing of the process gas discharged through the injection tube 71 with the dilution gas flow. This can allow the process gas (e.g., hydrogen) to be diluted from 100% concentration to <4% concentration in less than one second. The gas flow through the dilution gas line 70 can then be discharged through the process gas pump 51.

[0026] By providing a high flow of air and injecting nitrogen into the air stream at a high flow rate, the amount of nitrogen required to dilute the exhaust process gas to a safe level can be reduced.

[0027] Reference again Figure 1a and Figure 1b , the apparatus may include a gas injector 22 to provide a process gas into the process chamber 7. The gas injector 22 may be operably connected to a process gas line 27 in the purge chamber 9, such that the connection between the gas injector 22 and the process gas line 27 may be in a purge environment. By connecting the gas injector 22 to the process chamber 7 via the purge chamber 9, the process gas may be prevented from leaking into the rest of the apparatus 1. In addition, because the purge chamber 9 is purged, oxygen may not be present in the purge chamber 9, so that a reaction between hydrogen and oxygen may be avoided.

[0028] The apparatus may be provided with a source of hydrogen, for example from tank 28 ( Figure 1a) or a pipeline from a factory using the device. Hydrogen can be provided to the process chamber 7 via a process gas pipeline 27 and a gas injector 22. Hydrogen can be used in the process chamber to perform a hydrogen annealing process. The hydrogen annealing process can be performed at a high temperature, such as 300 to 700°C, preferably 400 to 600°C.

[0029] By connecting the process gas line 27 to the gas injector 22 in the purge chamber 9, if the connection could leak, the risk of process gas leaking into the rest of the apparatus 1 can be minimized. The purge chamber 9 can be constructed and arranged to purge the outside of the connection between the process gas line 27 and the gas injector 22. The connection can be realized with, for example, a ball joint 29, and if the joint could leak in the purge chamber 9, the risk of process gas leaking into the rest of the apparatus 1 can be minimized.

[0030] When the process gas is hydrogen and it leaks into a high temperature environment where oxygen is present, there is an immediate risk of the reaction generating heat and damaging equipment. The latter can lead to a safety hazard that should be avoided.

[0031] To ensure that hydrogen in the process chamber 7, process gas line 27, gas injector 22 and process gas exhaust conduit 19 does not react with oxygen in the event of some leakage, a purge chamber 9 may be provided. The purge chamber may be filled with an inert gas to ensure that there is no oxygen in the environment into which hydrogen may leak.

[0032] The hydrogen can be diluted with an inert gas to reduce the risk of reaction with oxygen. It can be discharged through the purge exhaust conduit 23 after sufficient dilution. The purge exhaust conduit 23 can be connected to a purge pump 53 to remove the gas from the purge chamber 9 to the outside of the device. Stream 31 can transport any leaking gas to the purge exhaust conduit 23 and the purge pump 53.

[0033] A heater 2 may be provided surrounding the process tube for heating the process chamber 7. The heater 2 may be arranged in a purge chamber 9. Any degassing products of the heater 2 may be pumped away via the purge chamber 9 and the purge exhaust conduit 23 using a purge pump 53.

[0034] The apparatus 1 may be provided with a heat exchanger (not shown) for cooling the inert gas in the purge chamber 9. If cooling of the process chamber 7 is required, for example at the end of a production run, this may be done.

[0035] Special reference Figure 1b , the apparatus 1 may be provided with a process gas generating unit 25, which is operably connected to the gas injector 22 via a process gas line 27 to generate process gas and provide it into the process chamber 7. By providing the gas generating unit 25 in the purge chamber 9, it is possible to avoid leakage of the process gas into the rest of the apparatus 1 when the gas generating unit 25 may leak.

[0036] Refer again Figure 1a and Figure 1b The device may be provided with side walls 35 to restrict access to the device 1. The device may be provided with a plurality of side walls 35 to form an open box open at the top 37.

[0037] The bottom can also be open. At the bottom, a droplet collection bucket can optionally be provided to collect any leaking liquid. The open box structure can be used as a protective cover to protect the interior of the device 1. This may be for safety purposes.

[0038] Since the open box structure may not require a ceiling, there is more space between the floor 41 and the ceiling 43 of a factory where the apparatus 1 can be used for the process chamber 7. The process chamber 7 can be correspondingly larger, and more wafers can be processed in the process chamber 7 at one time, making the apparatus 1 more economical.

[0039] Likewise, the device 1 may be provided with side walls 35 at the front and rear. The side walls 35 may be connected to provide an open box structure. The device 1 may be provided with a tool door 49 in the side walls 35 to provide a maintenance passage. A maintenance worker may access tools through the tool door 49.

[0040] The purge chamber 9 may be provided with a purge chamber door for accessing the process gas line 27 and the process gas exhaust duct 19 and / or any other device in the purge chamber 21. A maintenance worker may approach the process gas line 27, the process gas exhaust duct 19 and / or any other device in the purge chamber 9 through the purge chamber door.

[0041] A purge measurement device 55 may be provided which is constructed and arranged to measure a property of the gas in the purge chamber 9. The purge measurement device 55 may be disposed adjacent the purge gas exhaust conduit.

[0042] The purge measurement device 55 may be constructed and arranged to measure the oxygen concentration in the inert gas. Alternatively, it may be constructed and arranged to detect a specific oxygen level in the inert gas.

[0043] The purge measuring device 55 can be connected to the three-way valve 67 to test the purge measuring device 55. The three-way valve 67 can be connected to the purge gas exhaust conduit 23 in normal operation, but can be tested occasionally by connecting it to the air gas line 69 with a premixed test gas or normal air. The premixed gas can be nitrogen with a small percentage of oxygen (e.g., 600 PPM oxygen). The small percentage of oxygen in the PPM range can ensure a good test while ensuring that it does not take too much time to purge the three-way valve 67 and purge the measuring device 55 after the test.

[0044] The purge measurement device 55 may be constructed and arranged to detect hydrogen in the inert gas of the purge chamber 9. Measuring hydrogen may be in addition to or in lieu of measuring oxygen.

[0045] If nitrogen is used as the inert gas, the purge measuring device 55 may be constructed and arranged to detect or measure nitrogen in the purge chamber 9. Measuring nitrogen may be a supplement or alternative to measuring oxygen and / or hydrogen. Measuring all three gas concentrations makes the measurement safe and reliable, because when measuring 100% nitrogen, the measurement of oxygen and hydrogen should be 0%, which provides double safety. In the latter case, the function of the purge measuring device 55 can be checked.

[0046] Alternatively, the top purge measurement device 59 may be located at the top of the purge chamber 9 .

[0047] The inert gas used in the purge chamber 9 may be nitrogen. Alternatively, argon, helium, carbon dioxide or mixtures thereof may be considered. The mixture may also include nitrogen.

[0048] The process gas measurement device 57 may be constructed and arranged to measure a characteristic of the gas in the process chamber 7. The process gas measurement device 57 may be disposed proximate the process gas exhaust conduit 19. The process gas measurement device 57 may be constructed and arranged to detect oxygen as a measure of a characteristic of the process gas.

[0049] The process gas measurement device 57 can also be connected to the three-way valve to test the process gas measurement device 57. The three-way valve can be connected to the process gas exhaust conduit in normal operation, but can be tested occasionally by connecting the body to a pipeline with a pre-mixed test gas or ordinary air. The pre-mixed gas can be nitrogen with a small percentage of oxygen (for example, 600PPM oxygen). The small percentage of oxygen in the PPM range ensures a good test while ensuring that it does not take too much time to purge the three-way valve and process gas measurement device 57 after the test.

[0050] The apparatus may be provided with a process gas valve 60. The process gas valve 60 may be in the process gas line 27 for controlling the flow of process gas through the gas injector 22. The controller 63 may be operably connected to the process gas valve 60, the purge measuring device 55 and the process gas measuring device 53. When the purge measuring device 55 and / or the process gas measuring device 57 detect oxygen in the purge gas or the process gas, the controller 61 may control the process gas valve 60 to shut off the process gas to the injector 22. A portion of the process gas valve 60 may be provided in the purge chamber 9 so that any leakage of process gas near the process gas valve 60 may flow into the purge exhaust conduit 23.

[0051] The apparatus 1 may be provided with an inert gas valve 65 in the purge gas line 10 between the purge chamber 9 and the inert gas source to control the supply of the inert gas to the purge chamber 9 .

[0052] The controller 61 may be operably connected to the inert gas valve 65, the air valve 67, and the purge measurement device 55, which is constructed and arranged to measure oxygen in the purge chamber 9. The controller 61 may be programmed to open the air valve to check the operation of the measurement device 55 in measuring the presence of oxygen in the purge chamber 9. This may be done when the process gas valve 60 is closed for a period of time and the door 15 is open. In this case, if the measurement device 55 does not measure the presence of oxygen in the purge chamber 9, it is damaged, and the controller 61 may signal the user to stop processing the substrate and repair the measurement device 55.

[0053] The process chamber 7 may be an atmospheric process chamber operating at about 1 Atm. For example, the pressure is between 0.9 and 1.1 Atm, preferably between 0.98 and 1.02 Atm, even more preferably between 0.99 and 1.01 Atm. These atmospheric process chambers may be sensitive to leaks because they are substantially free of overpressure.

[0054] The process gas exhaust conduit 19 may be connected to a process gas pump 51 to remove gas from the process chamber 7. The process gas pump 51 may be controlled to maintain the pressure at about 1 Atm, such as between 0.9 and 1.1 Atm, preferably between 0.98 and 1.02 Atm.

[0055] A lift (not shown) operably connected to the controller 61 may be provided to move, for example, lift or lower the door 15, the pedestal 8, and the wafer boat 17 to load or unload the wafer boat 17. Gases, including inert and reactive precursor gases, may be provided to the process chamber 7 from a gas source, which may include a plurality of containers for containing various gases. Holes may be provided in the flange 11 to provide process gases from the gas source to the process chamber 7 using, for example, a syringe 22. The holes in the flange 11 may also be used to remove gases from the process chamber 7. The purge chamber 9 may be used to avoid the risk of leaks by purging the connection where the holes are located.

[0056] Thermocouples can be used to measure the temperature inside the process chamber 7. At higher temperatures, the thermocouples may oxidize, causing the measured temperature to drift or even damage the thermocouple. The oxidation rate may depend on the temperature, oxygen level and possible catalysts in the environment, such as acids.

[0057] Thermocouples may be located within the quartz bumps or tubes to isolate them from the process gases in the process chamber 7. The inlet of the quartz bumps may be open to the surrounding atmosphere to allow expanding gases in the quartz bumps to escape during heating and / or gases to enter during cooling. This may be necessary to prevent the quartz bumps from cracking due to high or low pressure inside the quartz bumps.

[0058] In deposition tools without a purge chamber 9, it may be advantageous to provide an inert gas purge to the interior of the quartz boss or tube that houses the thermocouple. This may isolate the thermocouple from oxygen. The quartz boss or tube may be closed and an overpressure relief valve may be provided to allow expansion gas to escape from the quartz boss or tube during heating while keeping the quartz tube purged with an inert gas. The purge gas provided may also keep the boss filled with the purge gas during cooling.

[0059] In deposition tools with a purge chamber 9, the inlet of the boss or tube housing the thermocouple can also be connected to the purge chamber 9 to isolate the thermocouple from oxygen. This solution provides a protective environment for the thermocouple to prevent oxidation and extend life.

[0060] Although the illustrative embodiments of the present invention have been described above in part with reference to the accompanying drawings, it should be understood that the present invention is not limited to these embodiments. Based on the study of the drawings, the disclosure and the appended claims, those skilled in the art can understand and implement variations of the disclosed embodiments when practicing the claimed invention.

[0061] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, it is noted that the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner to form new, not explicitly described embodiments.

Claims

1. An apparatus constructed and arranged to process a plurality of substrates, comprising: a process tube forming a process chamber; a gas injector for providing process gas into the process chamber; as well as A door configured to support a wafer boat having a plurality of substrates in a processing chamber and to seal the processing chamber, wherein the apparatus includes a purge chamber connected to an inert gas source, and wherein a gas injector is operably connected to a process gas line at an injector-gas line connection, the injector-gas line connection being located in the purge chamber to allow the injector-gas line connection to be purged.

2. The device according to claim 1, wherein: The purge chamber is connected to a purge exhaust conduit to remove purge gas from the purge chamber.

3. The device according to claim 1, wherein: The apparatus is provided with a hydrogen source to provide hydrogen to the process chamber through the process gas line and the gas injector.

4. The device according to claim 1, wherein: The purge chamber is constructed and arranged to surround the process tube.

5. The device according to claim 4, wherein: The apparatus includes a heater surrounding the process tube to heat the process chamber, and the heater is disposed in the purge chamber.

6. The device according to claim 1, wherein: The apparatus includes a process gas exhaust conduit operably connected to the process chamber to remove gas from the process chamber.

7. The device according to claim 6, wherein: The apparatus comprises a flange for supporting the process tube and provided with a flange opening leading to the process chamber, wherein the process gas exhaust conduit is operably connected to the process chamber to remove gas from the process chamber through the hole in the flange, wherein the connection between the process gas exhaust conduit and the process chamber is surrounded by the purge chamber to allow the connection between the process gas exhaust conduit and the process chamber to be purged.

8. The device according to claim 6, wherein: The apparatus comprises a dilution gas flow line to which the process gas exhaust conduit is coupled so as to inject gas removed from the process chamber into the dilution gas flow line, and wherein the apparatus comprises a nozzle for injecting nitrogen into the dilution gas flow line upstream of a point at which gas removed from the process chamber is injected into the dilution gas flow line.

9. The device according to claim 1, wherein: A purge measurement device constructed and arranged to measure a property of a gas in the purge chamber is provided.

10. The device according to claim 9, wherein: The purge measurement device is constructed and arranged to measure oxygen concentration.

11. The device according to claim 9, wherein: The purge measurement device is constructed and arranged to detect hydrogen.

12. The device according to claim 9, wherein: The purge measurement device is constructed and arranged to detect nitrogen.

13. The apparatus according to claim 1, wherein: A process gas measurement device constructed and arranged to measure a characteristic of a gas in the process chamber is provided.

14. The device according to claim 13, wherein: The process gas measurement device is constructed and arranged to detect oxygen.

15. The apparatus according to claim 1, wherein: The device is provided with an inert gas valve between the purge chamber and the inert gas source to control the supply of the inert gas to the purge chamber.

16. The device according to claim 15, wherein: The device is provided with an air valve between the purge chamber and an air supply source to control the supply of air to the purge chamber.

17. The apparatus according to claim 1, wherein: The apparatus is provided with a process gas valve between the process chamber and a process gas source to control the supply of the process gas to the process chamber.

18. The apparatus according to claim 16, wherein: The apparatus includes a controller operably connected to the inert gas valve, the air valve, and a measuring device constructed and arranged to measure oxygen in the purge chamber, wherein the controller is programmed to close the inert gas valve and open the air valve to check the operation of the measuring device in measuring the presence of oxygen in the purge chamber.

19. The apparatus according to claim 1, wherein: The process chamber is an atmospheric process chamber operating at a pressure of about 1 Atm.

20. The apparatus of claim 1, wherein: The purge chamber is constructed and arranged to purge the exterior of the connection between the process gas line and the gas injector.

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