A method for manufacturing a tungsten via

Abstract

The application provides a tungsten via hole manufacturing method, which comprises the following steps: providing an equipment comprising a first cavity and a second cavity connected by a vacuum transmission channel, and a cooling device is arranged in the vacuum transmission channel; placing a substrate with a via hole on the surface into the first cavity; introducing a first gas into the first cavity to deposit a tungsten film layer, so as to obtain an intermediate structure comprising the substrate and the tungsten film layer, and the tungsten film layer covers the surface of the substrate and fills into the via hole; pumping the first cavity, the vacuum transmission channel and the second cavity to the same preset vacuum degree; transmitting the intermediate structure into the second cavity through the vacuum transmission channel; introducing a second gas into the second cavity to etch and remove the tungsten film layer outside the via hole, so as to form a tungsten via hole; breaking the vacuum and taking out the substrate with the tungsten via hole from the equipment. The tungsten via hole manufacturing method can effectively improve the etching efficiency of tungsten, reduce the risk of defects and improve the yield of chips.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit manufacturing technology, and relates to a method for manufacturing tungsten through-holes. Background Technology

[0002] Tungsten metal, due to its low resistivity and good high-temperature stability, has been widely used in large-scale integrated circuits as through-holes and contact holes between metal layers. Its manufacturing process mainly involves two key steps: tungsten film deposition and tungsten film etching, which need to be performed on two different machines. Because of the involvement of multiple machines, the manufacturing efficiency of tungsten through-holes and tungsten contact holes is relatively low, and defects are easily introduced, thus affecting the chip yield.

[0003] Therefore, how to provide a method for manufacturing tungsten through-holes to improve the efficiency of tungsten etching and the yield of chips has become an important problem that needs to be solved by those skilled in the art.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a method for manufacturing tungsten vias to solve the problems of low manufacturing efficiency, easy introduction of defects, and poor chip yield in the prior art.

[0006] To achieve the above and other related objectives, the present invention provides a method for manufacturing tungsten through-holes, comprising the following steps:

[0007] A device is provided, the device includes a first cavity and a second cavity connected by a vacuum transfer channel, and a first isolation door is provided between the first cavity and the vacuum transfer channel, and a second isolation door is provided between the second cavity and the vacuum transfer channel, and a cooling device is provided inside the vacuum transfer channel;

[0008] A substrate with through holes on its surface is provided, and the substrate is placed in the first cavity;

[0009] A first gas is introduced into the first cavity to deposit a tungsten film layer, thereby obtaining an intermediate structure including the substrate and the tungsten film layer, wherein the tungsten film layer covers the surface of the substrate and fills the through-hole;

[0010] A vacuum is drawn to ensure that the first cavity, the vacuum transmission channel, and the second cavity all reach the same vacuum level.

[0011] The first isolation door, the cooling device, and the second isolation door are opened in a preset sequence, and the intermediate structure is transferred to the second cavity through the vacuum transfer channel within a predetermined cooling time.

[0012] The second isolation door is closed, and a second gas is introduced into the second cavity to etch and remove the tungsten film layer outside the through hole, while at least a portion of the tungsten film layer in the through hole is retained to form a tungsten through hole;

[0013] The vacuum is broken and the substrate with the tungsten through-hole is removed from the device.

[0014] Optionally, the substrate includes a substrate and a dielectric layer located on the substrate, and the via is formed in the dielectric layer.

[0015] Optionally, breaking the vacuum and removing the substrate with the tungsten through-hole formed from the device includes the following steps:

[0016] The vacuum in the second cavity is broken;

[0017] The substrate with the tungsten through-hole formed is removed from the second chamber.

[0018] Optionally, the vacuum transfer channel includes a transfer chamber and a third chamber, with a third isolation door provided between the third chamber and the transfer chamber. Breaking the vacuum and removing the substrate with the tungsten through-hole from the device includes the following steps:

[0019] The second isolation door and the third isolation door are opened in a preset order, and the substrate with the tungsten through hole is transferred to the third cavity through the transfer cavity;

[0020] Close the second isolation door and the third isolation door, and break the vacuum in the third cavity;

[0021] The substrate with the tungsten through-hole formed is removed from the third cavity.

[0022] Optionally, the second cavity is provided with a first radio frequency source and a second radio frequency source. The first radio frequency source is used to ionize the second gas to form plasma, and the second radio frequency source is used to control the plasma to move toward the substrate.

[0023] Optionally, during the etching process, the power range of the first radio frequency source is 100W to 3000W, the frequency range of the first radio frequency source is 400kHz to 70MHz, the power range of the second radio frequency source is 10W to 1000W, and the frequency range of the second radio frequency source is 400kHz to 70MHz.

[0024] Optionally, the first gas includes a deposition gas and an inert gas, wherein the deposition gas includes tungsten hexafluoride and silane, and the inert gas includes at least one of hydrogen, nitrogen, argon and helium.

[0025] Optionally, the second gas includes an etching gas and an inert gas, wherein the etching gas includes sulfur hexafluoride and the inert gas includes at least one of helium and argon.

[0026] Optionally, the step of transferring the intermediate structure into the second cavity via the vacuum transfer channel includes:

[0027] Open the first isolation door and transfer the intermediate structure from the first cavity to the vacuum transfer channel;

[0028] Close the first isolation door, turn on the cooling device to cool down the intermediate device, and transfer the intermediate structure to the second isolation door;

[0029] Turn off the cooling device, open the second isolation door, and place the intermediate structure into the second cavity.

[0030] Optionally, the upper surface of the tungsten through-hole is lower than the upper surface of the substrate.

[0031] As described above, the method for manufacturing tungsten through-holes according to the present invention includes: providing an apparatus comprising a first cavity and a second cavity connected by a vacuum transfer channel, wherein a cooling device is provided in the vacuum transfer channel; placing a substrate with through-holes on its surface in the first cavity; introducing a first gas into the first cavity to deposit a tungsten film layer, thereby obtaining an intermediate structure comprising a substrate and a tungsten film layer, wherein the tungsten film layer covers the surface of the substrate and fills the through-holes; evacuating the first cavity, the vacuum transfer channel, and the second cavity to the same predetermined vacuum level; transferring the intermediate structure to the second cavity through the vacuum transfer channel; introducing a second gas into the second cavity to etch and remove the tungsten film layer outside the through-holes, thereby forming tungsten through-holes; breaking the vacuum and removing the substrate with the tungsten through-holes from the apparatus. The method for manufacturing tungsten through-holes according to the present invention can effectively improve the efficiency of tungsten etching, reduce the risk of defects, and improve the yield of chips. Attached Figure Description

[0032] Figure 1 This diagram illustrates the structure obtained after forming a substrate, a dielectric layer, and a through-hole in a tungsten through-hole manufacturing method.

[0033] Figure 2 This diagram shows the structure obtained after forming a tungsten film layer in a tungsten through-hole manufacturing method.

[0034] Figure 3 This diagram shows the structure obtained after forming a tungsten through-hole in a tungsten through-hole manufacturing method.

[0035] Figure 4 The diagram shown is a process flow chart of the tungsten through-hole manufacturing method of the present invention.

[0036] Figure 5 The diagram shown is a structural schematic of the equipment used in the tungsten through-hole manufacturing method of the present invention.

[0037] Figure 6 The diagram shows a substrate placed in the first cavity in the tungsten through-hole manufacturing method of the present invention.

[0038] Figure 7 The diagram shown is a schematic of the structure obtained after forming a tungsten film layer in the tungsten through-hole manufacturing method of the present invention.

[0039] Figure 8 The diagram shows an intermediate structure placed in a second cavity in the tungsten through-hole manufacturing method of the present invention.

[0040] Figure 9 The diagram shown is a schematic representation of the structure obtained after forming a tungsten through-hole in the tungsten through-hole manufacturing method of the present invention.

[0041] Figure 10 This is another schematic diagram showing the structure obtained after forming a tungsten through-hole in the tungsten through-hole manufacturing method of the present invention.

[0042] Figure 11 This diagram illustrates one working state of the equipment in the tungsten through-hole manufacturing method of the present invention.

[0043] Explanation of reference numerals in the attached figures

[0044] 101 substrate

[0045] 102 Dielectric Layer

[0046] 103 Through Hole

[0047] 104 Deposition Equipment

[0048] 105 Deposition cavity

[0049] 106 Tungsten film

[0050] 107 Etching Equipment

[0051] 108 Etching Cavity

[0052] 109 Tungsten Via

[0053] 201 base

[0054] 2011 Substrate

[0055] 2012 Dielectric Layer

[0056] 202 Through Hole

[0057] 203 Equipment

[0058] 204 First cavity

[0059] 205 Tungsten film

[0060] 206 Vacuum Conveyor Channel

[0061] 2061 Transmission Chamber

[0062] 2062 Third Chamber

[0063] 2063 Third Isolation Door

[0064] 2064 Cooling device

[0065] 207 Second cavity

[0066] 208 First Isolation Door

[0067] 209 Second Isolation Door

[0068] 210 Tungsten Via

[0069] Steps S1 to S7 Detailed Implementation

[0070] Please see Figures 1 to 4 The diagram shows the structural features of a tungsten through-hole manufacturing method, which includes at least the following steps:

[0071] (1) As Figure 1 As shown, a substrate 101 is first provided, on which a dielectric layer 102 is provided, and through-holes 103 are formed in the dielectric layer 102;

[0072] (2) Figure 2 As shown, the substrate 101 is placed in the deposition chamber 105 of the deposition apparatus 104, and a tungsten film 106 is deposited. The tungsten film 106 covers the dielectric layer 102 and fills the through-hole 103 to obtain an intermediate structure.

[0073] (3) Figure 3 As shown, the intermediate structure is then placed in the etching chamber 108 of the etching equipment 107 to etch the tungsten film 106 and form a tungsten through hole 109.

[0074] The above-mentioned tungsten through-hole manufacturing methods involve a large number of devices, resulting in low manufacturing efficiency. Furthermore, different steps are completed in multiple different devices, and each device requires at least one vacuuming and vacuum breaking process. This leads to prolonged exposure of the chip to the atmosphere during transfer between different devices, thereby increasing the risk of defects and reducing the chip yield.

[0075] The inventors of this application have improved the preparation method of tungsten through-holes, so that the tungsten film deposition step and the tungsten film etching step can be completed in one device, which improves the tungsten etching efficiency, requires only one vacuum breaking, reduces the number of vacuum breaking steps in the tungsten through-hole manufacturing process, reduces the risk of defects, and improves the yield of chips.

[0076] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0077] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, or components.

[0078] Features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0079] In the detailed description of embodiments of the present invention, for ease of explanation, the schematic diagrams illustrating the device structure may be partially enlarged without adhering to the general scale, and the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. Furthermore, in actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0080] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0081] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0082] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0083] Please see Figure 4 The diagram shows a process flow chart of the tungsten through-hole manufacturing method of the present invention, which includes the following steps:

[0084] S1: A device is provided, the device includes a first cavity and a second cavity connected by a vacuum transmission channel, and a first isolation door is provided between the first cavity and the vacuum transmission channel, and a second isolation door is provided between the second cavity and the vacuum transmission channel, and a cooling device is provided inside the vacuum transmission channel;

[0085] S2: Provide a substrate with through holes on its surface, and place the substrate in the first cavity;

[0086] S3: A first gas is introduced into the first cavity to deposit a tungsten film layer, thereby obtaining an intermediate structure including the substrate and the tungsten film layer, wherein the tungsten film layer covers the surface of the substrate and fills the through hole;

[0087] S4: Perform vacuuming to ensure that the first cavity, the vacuum transmission channel, and the second cavity reach the same vacuum level;

[0088] S5: Open the first isolation door, the cooling device and the second isolation door in a preset order, and transfer the intermediate structure to the second cavity through the vacuum transfer channel within a predetermined cooling time;

[0089] S6: Close the second isolation door and introduce a second gas into the second cavity to etch away the tungsten film layer outside the through hole, while at least a portion of the tungsten film layer in the through hole is retained to form a tungsten through hole;

[0090] S7: Perform vacuum breaking and remove the substrate with the tungsten through-hole formed from the device.

[0091] The following will combine Figures 5 to 7 The various steps of the tungsten through-hole manufacturing method of the present invention are described in detail.

[0092] Please refer to the following first. Figure 5Step S1: Provide a device 203, the device 203 includes a first cavity 204 and a second cavity 207 connected by a vacuum transmission channel 206, and a first isolation door 208 is provided between the first cavity 204 and the vacuum transmission channel 206, and a second isolation door 209 is provided between the second cavity 207 and the vacuum transmission channel 206, and a cooling device is provided inside the vacuum transmission channel.

[0093] Specifically, the presence of the first isolation door 208 and the second isolation door 209 ensures that the process reaction gases and pressure states in the first cavity 204 and the second cavity 207 do not affect each other. That is, when tungsten film deposition is performed in the first cavity 204, the reaction gases in the first cavity 204 are blocked by the first isolation door 208 and will not enter the second cavity 207, thus preventing them from affecting subsequent processes. Similarly, when tungsten film etching is performed in the second cavity 207, the reaction gases in the second cavity 207 are blocked by the second isolation door 209 and will not leak into the first cavity 204. Please refer to [further details omitted]. Figure 6 Step S2: Provide a substrate 201 with a through hole 202 on its surface, and place the substrate 201 in the first cavity 204;

[0094] As an example, the substrate 201 includes a substrate 2011 and a dielectric layer 2012 located on the substrate 2011, and the via 202 is formed in the dielectric layer 2012.

[0095] As an example, the substrate 2011 may be made of silicon, germanium silicon, silicon carbide or other suitable substrate materials.

[0096] As an example, forming the dielectric layer 2012 on the substrate 2011 includes the following steps:

[0097] (1) Clean the substrate 2011 to remove dirt from the surface of the substrate 2011;

[0098] (2) The dielectric layer 2012 is deposited on the substrate 2011 by a deposition process, which can be any one of chemical vapor deposition, physical vapor deposition, low-pressure chemical vapor deposition or atomic layer deposition.

[0099] As an example, the material of the dielectric layer 2012 may be one or more of silicon nitride, silicon oxynitride, or other dielectric materials. In this embodiment, the material of the dielectric layer 2012 is silicon oxide.

[0100] As an example, creating the via 202 in the dielectric layer 2012 includes the following steps:

[0101] (1) A mask layer is formed on the surface of the dielectric layer 2012 by spin coating or other suitable methods;

[0102] (2) The mask layer is patterned using photolithography;

[0103] (3) Based on the patterned mask layer, the dielectric layer 2012 is subjected to dry etching and / or wet etching to obtain the via 202.

[0104] As an example, the via 202 partially penetrates the dielectric layer 2012 and is used to connect electrical components surface-mounted on the substrate 2011 or to connect two adjacent metal conductive layers. In other embodiments, the via 202 may also penetrate the dielectric layer 2012 entirely and be used to vertically connect electrical components on different layers to the metal conductive layers.

[0105] Please see again Figure 7 Step S3 is performed: a first gas is introduced into the first cavity 204 to deposit a tungsten film layer, resulting in an intermediate structure including the substrate 201 and the tungsten film layer 205, wherein the tungsten film layer 205 covers the surface of the substrate 201 and fills the through hole 202.

[0106] As an example, in the step of depositing the tungsten film layer 205, the pressure of the first cavity 204 is set to less than 100,000 mT.

[0107] As an example, the first gas includes a deposition gas and an inert gas. The deposition gas includes tungsten hexafluoride and silane, and the inert gas includes at least one of hydrogen, nitrogen, argon and helium. The specific combination and ratio of the gases in the first gas are not limited and depend on the specific requirements for deposition.

[0108] Specifically, during the deposition of the tungsten film layer 205, tungsten halides are typically used as the tungsten source gas. These gases are introduced into the heated first chamber 204, where they decompose at a certain temperature or react chemically with other reactive gases, thereby depositing the tungsten film layer 205 on the surface of the substrate 201. In this embodiment, tungsten hexafluoride is used as the tungsten source gas, and hydrogen is injected into the second chamber 207. At high temperatures, tungsten hexafluoride decomposes to generate tungsten atoms and fluorine atoms. The tungsten atoms generated from the decomposition are the basic material for forming the tungsten film layer. At the same time, hydrogen reacts with fluorine atoms to generate hydrogen fluoride gas, thereby causing tungsten atoms to be deposited on the surface of the substrate 201. As the reaction continues, tungsten atoms are continuously deposited, diffused, and crystallized on the surface of the substrate 201, gradually forming the continuous tungsten film layer 205.

[0109] Please see again Figure 7Step S4 is executed: a vacuum is drawn so that the first cavity 204, the vacuum transmission channel 206, and the second cavity 207 reach the same vacuum level, so that the first cavity 204, the vacuum transmission channel 206, and the second cavity 207 together form a transmission space that is always in a vacuum state, thereby improving the quality of the tungsten film layer 205. This is because if the substrate 201 comes into contact with external air, it is easy to introduce impurities and defects, causing the tungsten film layer 205 to oxidize, thereby reducing the quality of the tungsten film layer 205.

[0110] As an example, after the vacuuming step, the vacuum level of the first cavity 204 can be in the range of 0 Pa to 133 Pa, such as 30 Pa, 45 Pa, 55 Pa, 90 Pa, 115 Pa, 130 Pa, etc.; the vacuum level of the vacuum transmission channel 206 can be in the range of 0 Pa to 133 Pa, such as 30 Pa, 45 Pa, 55 Pa, 90 Pa, 115 Pa, 130 Pa, etc.; and the vacuum level of the second cavity 207 can be in the range of 0 Pa to 133 Pa, such as 30 Pa, 45 Pa, 55 Pa, 90 Pa, 115 Pa, 130 Pa, etc.

[0111] As an example, during the vacuuming step, the first cavity 204, the vacuum transmission channel 206, and the second cavity 207 each have their own extraction ports and vacuuming devices, i.e., three independently operating vacuum pumps. The three vacuum pumps simultaneously extract air, so that the first cavity 204, the vacuum transmission channel 206, and the second cavity 207 are all in the same vacuum state. The extraction step is performed after the tungsten film layer 205 is deposited, so that the first gas remaining in the first cavity 204 can be extracted from the first cavity 204 at the same time as the vacuuming, thereby preventing cross-contamination between the first cavity 204 and the second cavity 207.

[0112] Please see again Figure 8 Step S5 is executed as follows: the first isolation door 208, the cooling device, and the second isolation door 209 are opened in a preset order, and the intermediate structure is transferred to the second cavity 207 through the vacuum transfer channel 206 within a predetermined cooling time. As an example, the step of transferring the intermediate structure to the second cavity 207 through the vacuum transfer channel 206 includes:

[0113] (1) Open the first isolation door 208 and transfer the intermediate structure from the first cavity 204 to the vacuum transfer channel 206;

[0114] (2) Close the first isolation door 208, turn on the cooling device to cool down the intermediate structure, and transfer the intermediate structure to the second isolation door 209;

[0115] (3) Turn off the cooling device, open the second isolation door 209, and place the intermediate structure in the second cavity 207.

[0116] Specifically, the deposition process in the first cavity 204 is carried out at a relatively high temperature. After the tungsten film layer 205 is formed on the substrate 201, the intermediate structure needs to be cooled to avoid affecting subsequent processes. The cooling device is located in the vacuum transfer channel 206 and can lower the intermediate structure to the required low temperature within a predetermined cooling time. During the cooling process, a robotic arm in the vacuum transfer channel 206 transfers the intermediate structure to the second cavity 207, thereby shortening the overall process time and improving the efficiency of tungsten through-hole fabrication. In this embodiment, the cooling device uses a gas (such as nitrogen) as the cooling medium and works in conjunction with the vacuum pump of the vacuum transfer channel 206 to ensure that the vacuum level of the vacuum transfer channel 206 is maintained within the required range.

[0117] As an example, the diameter of the vacuum transfer channel 206 is greater than the height of the intermediate structure.

[0118] As an example, the first cavity 204 has a first support platform for supporting and fixing the substrate 201, and the second cavity 207 has a second support platform for supporting and fixing the intermediate structure. The vacuum transfer channel 206 is on the same horizontal plane as the first and second support platforms, so that the intermediate structure in the first cavity 204 after the tungsten film 205 deposition can be more easily transferred to the second cavity 207.

[0119] As an example, the vacuum channel can be transported by any of the following methods: conveyor belt transport, robotic arm transport, and electromagnetic transport. In this embodiment, the intermediate structure is transported by a robotic arm. The first cavity 204, the vacuum transport channel 206, and the second cavity 207 are equipped with robotic arms (not shown in the figure) that cooperate with each other to transport the intermediate structure, thereby realizing the transport of the intermediate structure.

[0120] Please see again Figure 9 Step S6 is executed: the second isolation door 109 is closed, and a second gas is introduced into the second cavity 207 to etch and remove the tungsten film layer 205 outside the through hole 202. At least a portion of the tungsten film layer 205 in the through hole 202 is retained to form a tungsten through hole 210.

[0121] As an example, the second cavity 207 is provided with a first radio frequency source and a second radio frequency source. The first radio frequency source is used to ionize the second gas to form plasma, and the second radio frequency source is used to control the plasma to move toward the substrate 201.

[0122] As an example, during the etching of the tungsten film layer 205, the power range of the first radio frequency source is 100W to 3000W, such as 200W, 500W, 1200W, 1700W, 2400W, 2700W, etc., and the frequency range of the first radio frequency source is 400kHz to 70MHz, such as 700kHz, 950kHz, 2000kHz, 5MHz, 12MHz. The second radio frequency source has a power range of 10W to 1000W, such as 20W, 50W, 120W, 370W, 640W, 870W, etc., and a frequency range of 400Khz to 70Mhz, such as 700Khz, 950Khz, 2000Khz, 5Mhz, 12Mhz, 30Mhz, 45Mhz, etc.

[0123] As an example, in the step of etching the tungsten film layer 205, the pressure of the second cavity 207 is set to less than 1000mT.

[0124] As an example, the second gas includes an etching gas and an inert gas. The etching gas includes sulfur hexafluoride, and the inert gas includes at least one of helium and argon. The specific combination and ratio of the gases in the second gas are not limited and depend on the specific requirements of the etching process. In this embodiment, the etching gas is sulfur hexafluoride and oxygen, and the inert gas is argon. The flow rate of sulfur hexafluoride is in the range of 10 sccm to 100 sccm, such as 30 sccm, 45 sccm, 75 sccm, 90 sccm, etc., and the flow rate of argon is in the range of 100 sccm to 1000 sccm, such as 300 sccm, 450 sccm, 550 sccm, 850 sccm, 900 sccm, etc. In other embodiments, the etching gas may also be only sulfur hexafluoride.

[0125] Then perform step S7: break the vacuum and remove the substrate 201 with the tungsten through-hole 210 formed from the device 203.

[0126] As an example, please refer to [link / reference]. Figure 9 Breaking the vacuum and removing the substrate 201 with the tungsten through-hole 210 formed in the device 203 includes the following steps:

[0127] (1) The vacuum in the second cavity 207 is broken (that is, the second cavity 207 is restored to atmospheric pressure);

[0128] (2) Remove the substrate 201 with the tungsten through-hole 210 formed from the second chamber 207.

[0129] Specifically, the first cavity 204 and the second cavity 207 are located in the same device 203, and the intermediate structure is transferred using the vacuum transfer channel 206. The deposition and etching steps of the tungsten film layer 205 are completed in one device, improving the etching efficiency of the tungsten film layer 205. Furthermore, the entire manufacturing method requires only one vacuum breaking operation, avoiding contact between the tungsten via 210 and external gases during the fabrication process, reducing the risk of defects and increasing the yield of chips requiring the tungsten via 210.

[0130] Specifically, when the second cavity 207 is subjected to a vacuum breaking operation, the vacuum transfer channel 206 remains in a vacuum state. In cases where multiple preparations of the tungsten through-hole 210 are required, the substrate 201 can be placed in the second cavity 207 in a vacuum breaking state. After evacuating the second cavity 207, the substrate 201 can be transferred to the first cavity 204 through the vacuum transfer channel 206 for the preparation process. This can further reduce the number of vacuuming operations and improve work efficiency.

[0131] For example, please refer to Figure 10 In another embodiment, the vacuum transfer channel 206 includes a transfer cavity 2061 and a third cavity 2062, with a third isolation door 2063 provided between the third cavity 2062 and the transfer cavity 2061. The cooling device 2064 is located inside the transfer cavity 2061. Breaking the vacuum and removing the substrate 201 with the tungsten through-hole 210 formed from the device 203 includes the following steps:

[0132] (1) Open the second isolation door 209 and the third isolation door 2063 in a preset order, and transfer the substrate 201 with the tungsten through hole 210 formed thereon to the third cavity 2062 through the transfer cavity 2051;

[0133] (2) Close the second isolation door 209 and the third isolation door 2063, and break the vacuum in the third cavity 2062 (so that the third cavity 2062 returns to atmospheric pressure);

[0134] (3) Remove the base 201 with the tungsten through hole 210 from the third cavity 2062.

[0135] Specifically, the third cavity 2062 is used to pick up and place the substrate 201. The transfer cavity 2061, the first cavity 204, and the second cavity 207 are always kept in a vacuum state. The entire manufacturing method only requires one vacuum breaking, avoiding contact between the tungsten through-hole 210 and external gas during the preparation process, reducing the risk of defects, and improving the yield of chips requiring the tungsten through-hole 210. Additionally, please refer to... Figure 11 The diagram shows a working state of the equipment in the tungsten through-hole manufacturing method of the present invention. After the intermediate structure is transferred to the second chamber 207, the new substrate 201 to be processed can enter the first chamber 204 for deposition through the third chamber 2062 and the transfer chamber 2061. This can further improve the preparation efficiency of the tungsten through-hole 210. In other words, the first chamber 204 and the second chamber 207 can work simultaneously, which can further shorten the time and improve the processing efficiency of products in batch processing.

[0136] As an example, the upper surface of the tungsten via 210 is lower than the upper surface of the substrate 201, so that the tungsten film layer 205 on the dielectric layer 2012 can be completely removed, preventing the tungsten film layer 205 from remaining and affecting the performance of the chip.

[0137] In summary, the tungsten through-hole manufacturing method of the present invention includes: providing an apparatus comprising a first cavity and a second cavity connected by a vacuum transfer channel, wherein a cooling device is provided in the vacuum transfer channel; placing a substrate with through-holes on its surface in the first cavity; introducing a first gas into the first cavity to deposit a tungsten film layer, thereby obtaining an intermediate structure comprising a substrate and a tungsten film layer, wherein the tungsten film layer covers the surface of the substrate and fills the through-holes; evacuating the first cavity, the vacuum transfer channel, and the second cavity to the same preset vacuum level; transferring the intermediate structure to the second cavity through the vacuum transfer channel; introducing a second gas into the second cavity to etch and remove the tungsten film layer outside the through-holes, thereby forming tungsten through-holes; breaking the vacuum and removing the substrate with the tungsten through-holes from the apparatus. The tungsten through-hole manufacturing method of the present invention can effectively reduce the number of vacuum breaking operations in the reaction chamber, improve the efficiency of tungsten etching, reduce the risk of defects, and improve the yield of chips. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has high industrial applicability.

[0138] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for manufacturing a tungsten through-hole, characterized in that, Includes the following steps: A device is provided, the device comprising a first cavity and a second cavity connected by a vacuum transmission channel, a first isolation door being provided between the first cavity and the vacuum transmission channel, a second isolation door being provided between the second cavity and the vacuum transmission channel, and a cooling device being provided inside the vacuum transmission channel, the cooling device using gas as a cooling medium and working in conjunction with a vacuum pump of the vacuum transmission channel; A substrate with through holes on its surface is provided, and the substrate is placed in the first cavity; A first gas is introduced into the first cavity to deposit a tungsten film layer, thereby obtaining an intermediate structure including the substrate and the tungsten film layer, wherein the tungsten film layer covers the surface of the substrate and fills the through-hole; A vacuum is drawn to ensure that the first cavity, the vacuum transmission channel, and the second cavity reach the same vacuum level. The first isolation door, the cooling device, and the second isolation door are opened in a preset sequence, and the intermediate structure is transferred to the second cavity through the vacuum transfer channel within a predetermined cooling time. The second isolation door is closed, and a second gas is introduced into the second cavity to etch and remove the tungsten film layer outside the through hole, while at least a portion of the tungsten film layer in the through hole is retained to form a tungsten through hole; The vacuum is broken and the substrate with the tungsten through-hole is removed from the device.

2. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: The substrate includes a substrate and a dielectric layer located on the substrate, and the via is formed in the dielectric layer.

3. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: Breaking the vacuum and removing the substrate with the tungsten through-hole from the device includes the following steps: The vacuum in the second cavity is broken; The substrate with the tungsten through-hole formed is removed from the second cavity.

4. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: The vacuum transfer channel includes a transfer chamber and a third chamber, with a third isolation door provided between the third chamber and the transfer chamber. Breaking the vacuum and removing the substrate with the tungsten through-hole from the device includes the following steps: The second isolation door and the third isolation door are opened in a preset order, and the substrate with the tungsten through hole is transferred to the third cavity through the transfer cavity; Close the second isolation door and the third isolation door, and break the vacuum in the third cavity; The substrate with the tungsten through-hole formed is removed from the third cavity.

5. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: The second cavity is provided with a first radio frequency source and a second radio frequency source. The first radio frequency source is used to ionize the second gas to form plasma, and the second radio frequency source is used to control the plasma to move toward the substrate.

6. The method for manufacturing tungsten through-holes according to claim 5, characterized in that: During the etching process, the power range of the first radio frequency source is 100 W to 3000 W, and the frequency range of the first radio frequency source is 400 kHz to 70 MHz. The power range of the second radio frequency source is 10 W to 1000 W, and the frequency range of the second radio frequency source is 400 kHz to 70 MHz.

7. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: The first gas includes a deposition gas and an inert gas. The deposition gas includes tungsten hexafluoride and silane, and the inert gas includes at least one of hydrogen, nitrogen, argon and helium.

8. The method for manufacturing tungsten through-holes according to claim 1, characterized in that: The second gas includes an etching gas and an inert gas, wherein the etching gas includes sulfur hexafluoride and the inert gas includes at least one of helium and argon.

9. The method for manufacturing a tungsten through-hole according to claim 1, characterized in that: The step of transferring the intermediate structure into the second cavity through the vacuum transfer channel includes: Open the first isolation door and transfer the intermediate structure from the first cavity to the vacuum transfer channel; Close the first isolation door, turn on the cooling device to cool the intermediate structure, and then transfer the intermediate structure to the second isolation door; Turn off the cooling device, open the second isolation door, and place the intermediate structure in the second cavity.

10. The method for manufacturing a tungsten through-hole according to claim 1, characterized in that: The upper surface of the tungsten through-hole is lower than the upper surface of the substrate.

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