Method for improving etching productivity and etching system

Abstract

This invention provides a method and system for improving etching capacity, belonging to the field of semiconductor manufacturing technology. The method for improving etching capacity includes: setting the number of etching passes k and the single etching time k of the substrate based on the total etching time T of the substrate, where T = ; first, sending multiple substrates into a cooling chamber, then selecting one to be sent into an etching chamber for etching; after the etching time reaches the single etching time, sending the substrate back to the cooling chamber, and sending another substrate into the etching chamber for etching, while simultaneously cooling the cooling chamber, and repeating this process until all substrates have reached the total etching time T. This application avoids the increased cost caused by adding a cooling device to the etching chamber, and can effectively control the temperature of the substrate, thereby improving the substrate production efficiency.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing technology, and specifically relates to a method and etching system for improving etching capacity. Background Technology

[0002] Etching is the core process in semiconductor patterning, crucial for forming precise microstructures and patterns. During etching, whether physical etching, chemical etching, or a combination of both, the removal of surface material through physical or chemical processes generates heat, leading to temperature increases. Excessive temperature can adversely affect the etched material or cause overheating of components in the etching equipment. Therefore, temperature control and cooling are critical during long-term, continuous etching processes.

[0003] In the relevant existing technologies, the temperature control or cooling methods used in the etching process are to add a cooling device in the etching chamber to control or cool the substrate, or to add a cooling step in the etching process. The former requires the addition of a device, which increases equipment costs and has limited cooling effect, while the latter prolongs the etching time and reduces production capacity. Both of these methods have a certain impact on the production efficiency of the substrate. Summary of the Invention

[0004] The present invention aims to at least solve one of the aforementioned technical problems existing in the prior art. To this end, in a first aspect, the present invention provides a method for improving etching capacity, which can control production costs while increasing capacity, thus overcoming the shortcomings of traditional temperature control or cooling methods.

[0005] Secondly, the present invention provides an etching system capable of implementing the above-described method.

[0006] A method for improving etching yield according to a first aspect of the present invention includes: Based on the total etching time T of the substrate, the etching number k and the single etching time of the substrate are set. ,in T= ; First, multiple substrates are fed into a cooling chamber, and then one of the substrates is selected and fed into an etching chamber for etching, wherein the etching time of the substrate reaches the single etching time. Then, the substrate is sent back to the cooling chamber, and another substrate is sent into the etching chamber for etching. At the same time, all the substrates in the cooling chamber are cooled. This process is repeated until all the substrates have reached the total etching time T.

[0007] The method for improving etching capacity according to embodiments of the present invention has at least the following beneficial effects: The method for improving etching capacity in this embodiment effectively avoids excessive temperature rise in a single etching process by dividing the total etching time of the substrate into k times, resulting in good temperature control.

[0008] Furthermore, the alternating feeding of multiple substrates into the etching chamber helps maintain the etching environment within the chamber, such as the etching temperature. After changing substrates, etching operations can be quickly resumed. Compared to adding cooling steps during the etching process in the etching chamber, the etching chamber remains essentially in the etching operation, which can effectively improve production capacity.

[0009] Meanwhile, storing multiple substrates in the cooling chamber allows for the cooling of all substrates within the chamber, which helps control the substrate temperature and prevents overheating.

[0010] Therefore, although the method for improving etching capacity in this embodiment involves alternating etching and cooling for a single substrate, the etching chamber and cooling chamber remain in their respective working states throughout the entire process. The cumulative processing time is close to the sum of the total etching time T for all substrates. This avoids the increased cost caused by adding cooling devices to the etching chamber and effectively controls the temperature of the substrate, thereby improving the production efficiency of the substrate.

[0011] According to some embodiments of the present invention, when cooling the substrate, cooling gas is introduced into the cooling chamber, and when replacing the substrate, the supply of cooling gas is stopped.

[0012] According to some embodiments of the present invention, during cooling, the air pressure in the cooling chamber is controlled between 130 Pa and 1300 Pa.

[0013] According to some embodiments of the present invention, when the substrate is fed into the etching chamber, the cooling chamber is first evacuated to a first vacuum level, the etching chamber is evacuated to a second vacuum level, and then the two are controlled to be connected to transport the substrate.

[0014] According to some embodiments of the present invention, the first vacuum degree is 1E-2 Pa to 9E-2 Pa, and the second vacuum degree is 1E-3 Pa to 9E-4 Pa.

[0015] According to some embodiments of the present invention, during etching, the gas pressure in the etching chamber is controlled between 1 mTorr and 200 mTorr.

[0016] According to some embodiments of the present invention, the substrate has a material thickness of H and an etching rate of A, and the total etching time of the substrate is... .

[0017] According to some embodiments of the present invention, the heating rate of the substrate during the etching process is B, the temperature tolerance of the material to be etched is M, and the room temperature is m, wherein the duration of a single etching cycle is... .

[0018] According to some embodiments of the present invention, the number of etching cycles of the substrate And round up to the nearest integer.

[0019] According to the etching system of the second aspect of the present invention, the method for improving etching capacity of any of the above embodiments can be implemented.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and some of these additional aspects and advantages will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic flowchart of a method for improving etching capacity in this invention; Figure 2 This is a schematic diagram illustrating the structural principle of the etching system in this invention.

[0022] In the picture: 100 - Etching chamber; 200 - Cooling chamber; 201 - Multi-layer stage; 300-Substrate. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0024] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0025] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0026] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0027] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0028] Combination Figure 1 and Figure 2 The present invention provides a method for improving etching productivity, comprising: Based on the total etching time T of the substrate 300, the number of etching cycles k and the single etching time of the substrate 300 are set. ,in T= ; First, multiple substrates 300 are fed into a cooling chamber 200. Then, one of the substrates 300 is selected and fed into an etching chamber 100 for etching. The etching time of the substrate 300 reaches the single etching time. Then, the substrate 300 is sent back to the cooling chamber 200, and another substrate 300 is sent into the etching chamber 100 for etching. At the same time, all substrates 300 in the cooling chamber 200 are cooled. This process is repeated until all substrates 300 have reached the total etching time T.

[0029] It should be noted that the duration of a single etching operation... They can be the same or different, as mentioned above. to The etching times can be the same or different. Furthermore, the total etching time T of the substrate 300 is set according to the actual processing requirements, and it is not required that the total etching time T of the substrates 300 be the same.

[0030] The method for improving etching capacity in this embodiment divides the total etching time of the substrate 300 into k times, which can effectively avoid excessive temperature rise in a single etching and achieve good temperature control.

[0031] Furthermore, the alternating feeding of multiple substrates 300 into the etching chamber 100 for etching helps maintain the etching environment within the etching chamber 100, such as the etching temperature. After changing the substrate 300, the etching operation can be started quickly. Compared to adding a cooling step during the etching process in the etching chamber 100, the etching chamber 100 is basically kept in the etching operation, which can effectively improve the production capacity.

[0032] Meanwhile, storing multiple substrates 300 in the cooling chamber 200 allows for the cooling of all substrates 300 within the cooling chamber 200, which helps control the temperature of the substrates 300 and prevents overheating.

[0033] Therefore, although the method for improving etching capacity in this embodiment involves alternating etching and cooling for a single substrate 300, the etching chamber 100 and the cooling chamber 200 are basically maintained in their respective working states throughout the entire processing. The cumulative processing time is close to the sum of the total etching time T of all substrates 300. This avoids the increased cost caused by adding a cooling device in the etching chamber 100 and can effectively control the temperature of the substrate 300, thereby improving the production efficiency of the substrate 300.

[0034] In some embodiments of the present invention, when cooling the substrate 300, cooling gas is introduced into the cooling chamber 200, and when the substrate 300 is replaced, the supply of cooling gas is stopped.

[0035] In this embodiment, cooling gas is used to cool the substrate 300, which effectively ensures that the entire substrate 300 is cooled. The cooling gas can directly contact the substrate 300, resulting in high cooling efficiency. The cooling gas can be flexibly designed according to different etching materials, such as using argon, carbon tetrafluoride, etc.

[0036] Furthermore, stopping the supply of cooling gas when replacing the substrate 300 can prevent cooling gas from entering the etching chamber 100.

[0037] Alternatively, the substrate 300 can be cooled by using the structure supporting the substrate 300 within the cooling chamber 200 for heat conduction. For example, a medium channel can be provided on the structure supporting the substrate 300 within the cooling chamber 200, and the cooling medium can be used to carry away the temperature of the substrate 300 by passing through the medium channel, thereby achieving cooling.

[0038] In some embodiments of the present invention, during cooling, the air pressure in the cooling chamber 200 is controlled between 130 Pa and 1300 Pa, such as 130 Pa, 150 Pa, 200 Pa, 300 Pa, 400 Pa, 500 Pa, 600 Pa, 660 Pa, 700 Pa, 800 Pa, 880 Pa, 900 Pa, 1000 Pa, 1100 Pa, 1200 Pa, 1300 Pa, etc.

[0039] In actual production, the appropriate cooling air pressure can be set according to the performance of the substrate 300 to ensure cooling efficiency.

[0040] In some embodiments of the present invention, when the substrate 300 is sent into the etching chamber 100, the cooling chamber 200 is first evacuated to a first vacuum level and the etching chamber 100 is evacuated to a second vacuum level, and then the two are controlled to be connected to transport the substrate 300.

[0041] Understandably, in traditional etching processes, replacing the substrate 300 requires breaking the vacuum before the substrate 300 can be removed from the etching chamber 100. However, in this embodiment, the substrate 300 is stored in the cooling chamber 200. By evacuating the cooling chamber 200 to a first vacuum level, the impact of breaking the vacuum on production efficiency is avoided, which helps to improve the efficiency of substrate 300 replacement and thus increase production capacity.

[0042] Since the etching chamber 100 has high requirements for vacuum level, in practical applications, the second vacuum level can be controlled to be greater than the first vacuum level. Although the vacuum levels of the cooling chamber 200 and the etching chamber 100 are different, this will not affect the transfer of the substrate 300, thus balancing the vacuum level of the etching chamber 100 and the transfer efficiency of the substrate 300.

[0043] In practical applications, wafer replacement can be performed when the first vacuum level and the second vacuum level differ by two orders of magnitude. After wafer replacement, the vacuum levels of the two chambers are restored first, and then cooling gas is introduced into the cooling chamber 200 for cooling and process gas is introduced into the etching chamber 100 for etching.

[0044] In some embodiments of the present invention, the first vacuum level is 1E-2 Pa to 9E-2 Pa, and the second vacuum level is 1E-3 Pa to 9E-4 Pa. The specific values ​​of both can be flexibly set according to actual etching requirements.

[0045] In some embodiments of the present invention, during etching, the gas pressure in the etching chamber 100 is controlled between 1 mTorr and 200 mTorr, such as 1 mTorr, 2 mTorr, 2.5 mTorr, 30 mTorr, 40 mTorr, 50 mTorr, 60 mTorr, 70 mTorr, 80 mTorr, 90 mTorr, 100 mTorr, 150 mTorr, and 200 mTorr. Those skilled in the art can flexibly design this according to the properties of the material to be etched and the properties of the process gas.

[0046] In some embodiments of the present invention, the material thickness to be etched on the substrate 300 is H, the etching rate is A, and the total etching time of the substrate 300 is... .

[0047] The thickness H of the material to be etched is usually in the micrometer range, such as 2μm to 5μm, while the etching rate A is generally in the micrometer range per minute, such as 0.2μm / min to 0.8μm / min. Both of these are directly available parameters, so the total etching time T required for the substrate 300 can be calculated.

[0048] In some embodiments of the present invention, the heating rate of the substrate 300 during the etching process is B, the tolerance temperature of the material to be etched is M, and the room temperature is m, wherein the duration of a single etching cycle is... .

[0049] Similarly, the etch resistance temperature M of the material to be etched, the room temperature m, and the heating rate B of the substrate 300 can all be directly known. During the etching process, the time it takes for the substrate 300 to rise from room temperature m to no more than the etch resistance temperature M is... Therefore, the duration of a single etching session is controlled. Keeping the time shorter than this value can effectively prevent excessive heating.

[0050] In some embodiments of the present invention, the number of etching cycles of the substrate 300 And round up to the nearest integer. For example, the total etching time. Duration of a single etching session If the ratio is 1.5, then the number of etchings k should be set to two.

[0051] Furthermore, the cooling rate of substrate 300 during the cooling process is C. When switching substrate 300, the time t for substrate 300 to be transferred from etching chamber 100 to cooling chamber 200 for cooling should be greater than [a certain value]. *B / C.

[0052] In some embodiments of the present invention, methods for improving etching productivity include: Based on the material thickness H to be etched on substrate 300 and the etching rate A, the total etching time T of substrate 300 is determined, where ; Based on the heating rate B of the substrate 300 during the etching process, the tolerance temperature M of the material to be etched, and the room temperature m, the time required for the substrate 300 to heat from room temperature m to the tolerance temperature M is obtained as follows: ; Set the single etching time of substrate 300 And set the cumulative etching count k of substrate 300. k is the ratio Round up; This determines the number of etching cycles k of the substrate 300 and the duration of each etching cycle. , Both conditions are met: T= ; Then, the vacuum in the cooling chamber 200 is broken, and n substrates 300 are sent into the cooling chamber 200, and then the set vacuum level is restored. One substrate 300 is selected from n substrates 300 and sent into the etching chamber 100. After the two chambers are separated, the substrate 300 in the etching chamber 100 is etched for a duration of [duration missing]. After etching is completed, the first substrate 300 is taken out into the cooling chamber 200, and the second substrate 300 is sent from the cooling chamber 200 into the etching chamber 100. The etching chamber 100 and the cooling chamber 200 are separated again. The substrate 300 in the etching chamber 100 is etched, and all the substrates 300 in the cooling chamber 200 are cooled at the same time. This process is repeated until all n substrates 300 have completed the first etching. Then, the first substrate 300 is sent into the etching chamber 100 for a second etching, the etching time being... After etching is completed, the first substrate 300 is taken out into the cooling chamber 200, and the second substrate 300 is sent from the cooling chamber 200 into the etching chamber 100. The etching chamber 100 and the cooling chamber 200 are separated again. The substrate 300 in the etching chamber 100 is etched, and all substrates 300 in the cooling chamber 200 are cooled at the same time. This process is repeated until all n substrates 300 have completed the second etching. Repeat the above steps until all n substrates 300 have completed the kth etching.

[0053] In this embodiment, since n substrates 300 are fed into the cooling chamber 200, the substrate 300 will only proceed to the next etching step after all substrates 300 have completed the etching process in the corresponding sequence. This effectively ensures the cooling time and cooling effect of the substrates 300 after etching. That is, if the cooling rate of the substrate 300 during the cooling process is C, when switching substrates 300, the process design of this embodiment can ensure that the time t for the substrate 300 to transfer from the etching chamber 100 to the cooling chamber 200 for cooling is greater than [a certain value]. *B / C.

[0054] Embodiments of the present invention also provide an etching system capable of achieving the method for improving etching capacity in any of the above embodiments.

[0055] Reference Figure 2 Specifically, the etching system includes an etching chamber 100, a cooling chamber 200, and a wafer transfer robot.

[0056] The etching chamber 100 and the cooling chamber 200 are arranged adjacent to each other. The etching chamber 100 is provided with a plate changing window that communicates with the cooling chamber 200, and a first valve for controlling the opening and closing of the plate changing window.

[0057] The cooling chamber 200 is provided with a multi-layer platform 201, which is arranged vertically and vertically to support the substrate 300 layer by layer.

[0058] A transfer robot is located in the cooling chamber 200 to remove the substrate 300 from the etching chamber 100 onto the multilayer stage 201, or to transfer the substrate 300 from the multilayer stage 201 into the etching chamber 100.

[0059] An etching method using the above etching system includes: Initially, the number of substrates 300 in the cooling chamber 200 is 0, the etching chamber 100 is in a high vacuum state, and the cooling chamber 200 is in a low vacuum state. First, the cooling chamber 200 is devastated to atmospheric pressure. Then, n substrates 300 are sent into the cooling chamber 200, so that one substrate 300 is placed on each layer of the multilayer stage 201. Then, the cooling chamber 200 is closed and re-evacuated to a low vacuum state. Open the first valve, and the transfer robot will send the first substrate 300 into the etching chamber 100; Close the first valve and initiate etching until the specified time is reached. ; Open the first valve, remove the first substrate 300, and send the second substrate 300 into the etching chamber 100; Close the first valve and initiate etching on the second substrate 300 until the specified time is reached. At the same time, cooling gas is introduced into the cooling chamber 200 for cooling; Repeat the above steps until all n substrates 300 have completed the first etching. Then, send the first substrate 300 into the etching chamber 100 and start etching until the specified time is reached. Then replace the substrate 300; Repeat the above steps until all n substrates have been etched k times.

[0060] In this embodiment, the substrate 300 is alternately fed into the etching chamber 100, so that the etching chamber 100 is basically kept in working state. At the same time, the substrate 300 can be sent into the cooling chamber 200 for cooling in time after heating up, which can balance production efficiency and temperature control, and is conducive to improving production capacity.

[0061] In some embodiments of the present invention, the multi-layer stage 201 can be moved and adjusted in a direction perpendicular to the wafer changing window, and a lifting mechanism is provided in the cooling chamber 200. The lifting mechanism is provided with a support part that can be raised and lowered. The wafer transfer robot is located below the multi-layer stage 201 and faces the wafer changing window.

[0062] During operation, the multi-layer stage 201 moves laterally and the support section is raised and lowered to facilitate the transfer of the substrate 300 between the two. Simultaneously, in conjunction with the movement of the transfer robot, the substrate 300 is transferred between the support section and the transfer robot. The transfer of the substrate 300 between the cooling chamber 200 and the outside can also be achieved by moving the support section upward or downward out of the cooling chamber 200.

[0063] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A method for improving etching productivity, characterized in that, include: Based on the total etching time T of the substrate, the etching number k and the single etching time of the substrate are set. ,in T= ; First, multiple substrates are fed into a cooling chamber, and then one of the substrates is selected and fed into an etching chamber for etching, wherein the etching time of the substrate reaches the single etching time. Then, the substrate is sent back to the cooling chamber, and another substrate is sent into the etching chamber for etching. At the same time, all the substrates in the cooling chamber are cooled. This process is repeated until all the substrates have reached the total etching time T.

2. The method for improving etching capacity according to claim 1, characterized in that, When cooling the substrate, cooling gas is introduced into the cooling chamber; when replacing the substrate, the supply of cooling gas is stopped.

3. The method for improving etching capacity according to claim 2, characterized in that, During cooling, the air pressure in the cooling chamber is controlled between 130 Pa and 1300 Pa.

4. The method for improving etching capacity according to claim 1, characterized in that, When the substrate is fed into the etching chamber, the cooling chamber is first evacuated to a first vacuum level, the etching chamber is evacuated to a second vacuum level, and then the two are controlled to be connected to transport the substrate.

5. The method for improving etching capacity according to claim 4, characterized in that, The first vacuum level is 1E-2 Pa to 9E-2 Pa, and the second vacuum level is 1E-3 Pa to 9E-4 Pa.

6. The method for improving etching capacity according to claim 1, characterized in that, During etching, the gas pressure in the etching chamber is controlled between 1 mTorr and 200 mTorr.

7. The method for improving etching productivity according to claim 1, characterized in that, The substrate has a material thickness of H and an etching rate of A, and the total etching time is [not specified]. .

8. The method for improving etching capacity according to claim 1, characterized in that, The substrate has a heating rate of B during the etching process, the material to be etched has a tolerance temperature of M, and the room temperature is m. The duration of a single etching cycle is... .

9. The method for improving etching productivity according to claim 8, characterized in that, The number of etchings of the substrate And round up to the nearest integer.

10. An etching system, characterized in that, The method for improving etching capacity as described in any one of claims 1 to 9 is capable of achieving this.

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