Method of implementing glass via structures and glass vias

Abstract

The application discloses a method for realizing a glass via structure and the glass via, comprising the following steps: forming a plurality of photoresist masks on the surface of a glass substrate, and performing a first treatment on the surface of the mask; performing an etching process to form a via on the substrate, wherein the etching process comprises a periodic cycle etching process formed by a first etching step and a second etching step; the first etching step uses neutral particles in the plasma of a first gas to perform isotropic first etching on the substrate, and a first polymer layer is formed on the inner wall of the forming via and the mask to protect the same; the second etching step uses charged particles in the plasma of a second gas to perform anisotropic second etching on the first polymer layer on the bottom of the inner wall, so that the underlying substrate is exposed to the first etching again; and a second treatment process is performed. The application can simplify the process, improve the selection ratio, improve the efficiency, and realize better side wall smoothness.

Description

Technical Field

[0001] This application relates to the field of semiconductor processing technology, and in particular to a method for realizing a glass through-hole structure and the glass through-hole obtained by using this method. Background Technology

[0002] Currently, the dry etching process used in glass through-hole (TGV) fabrication typically involves the following steps:

[0003] 1) First, a metal Al layer is deposited on the substrate as a hard mask layer during TGV etching;

[0004] 2) Cover the Al layer with photoresist and expose the area to be etched on the Al layer using photolithography;

[0005] 3) The exposed Al layer on the area to be etched is etched using Cl2 / BCL3 plasma to form an Al pattern;

[0006] 4) Use O2 to remove the photoresist;

[0007] 5) Using the Al pattern as a mask, perform TGV dry etching.

[0008] However, the actual process of TGV etching described above is relatively complex, inefficient, and costly. Furthermore, the use of metal masks can introduce byproduct contamination problems. Moreover, existing TGV etching processes typically employ non-periodic cyclic etching (as opposed to the periodic cyclic etching method of deposition-etching-deposition-etching), resulting in relatively poor dimensional uniformity and difficulty in meeting the increasing demands for larger aspect ratios and higher interconnect densities. Therefore, it is necessary to investigate a process method that can significantly improve upon these problems. Summary of the Invention

[0009] The purpose of this application is to overcome the above-mentioned problems existing in the prior art and provide a method for realizing a glass via structure and a glass via, so as to avoid the use of metal masks, simplify the process, improve efficiency, and improve the mask selectivity, so as to facilitate the fabrication of glass vias with higher aspect ratio and higher interconnect density.

[0010] To achieve the above objectives, the technical solution of this application is as follows:

[0011] According to a first aspect of this application, embodiments of this application provide a method for implementing a glass through-hole structure, including:

[0012] Provide a substrate made of glass material;

[0013] Multiple photoresist masks are formed on the surface of the substrate, with a first opening between two adjacent masks;

[0014] An etching process is performed to etch the substrate exposed in the first opening to form a through-hole on the substrate;

[0015] The etching process includes multiple periodic cyclic etching steps formed sequentially by a first etching step and a second etching step.

[0016] The first etching step uses neutral particles in the plasma of the first gas to perform isotropic first etching on the substrate and forms a first polymer layer on the inner wall of the forming via and the mask to protect the inner wall and the mask during the first etching.

[0017] The second etching step uses charged particles in the plasma of the second gas to perform anisotropic second etching on the first polymer layer on the bottom of the inner wall, forming a second opening on the bottom of the inner wall and exposing the substrate so that the first etching can be performed again through the second opening;

[0018] The first gas is a first carbon-fluorine gas with a carbon-fluorine ratio greater than or equal to 1:3, and the second gas is a first inert gas;

[0019] Before performing the etching process, the second etching step contained in the etching process is used as a first processing process. The first processing process uses charged particles in the plasma of the first inert gas to perform a first treatment on the surface of the mask to reduce the surface roughness.

[0020] In addition, a second processing step is performed to improve the smoothness of the sidewalls of the through hole.

[0021] In some embodiments, after the through hole is formed, the second processing step is performed to perform a second processing on the sidewall of the formed through hole.

[0022] In some embodiments, during the formation of the through-hole, and after each first etching step of a first preset number of times is completed, the second processing process is performed once to perform a second processing on the sidewall of the through-hole being formed.

[0023] In some embodiments, the second processing step includes a deposition step and a third etching step; the deposition step uses charged particles in a plasma of a third gas to deposit a second polymer layer on the sidewall; the third etching step uses charged particles in a plasma of a fourth gas to remove a portion of the thickness of the second polymer layer deposited on the sidewall and reacts with the substrate material on the surface of the exposed protrusions on the sidewall to remove at least a portion of the protrusions; wherein the third gas is a second fluorocarbon gas with a carbon-to-fluorine ratio greater than or equal to 1:2, and the fourth gas is a third fluorocarbon gas with a carbon-to-fluorine ratio less than 1:3.

[0024] In some embodiments, when performing the second processing step, the deposition step and the third etching step are repeated sequentially a second preset number of times.

[0025] In some embodiments, the first etching step is performed using a first pressure and a first bias power, the second etching step is performed using a second pressure and a second bias power, the deposition step is performed using a third pressure and a third bias power, and the third etching step is performed using a fourth pressure and a fourth bias power, wherein the third pressure is greater than the first pressure, the first pressure is greater than the second pressure and the fourth pressure, the fourth bias power is greater than the second bias power, and the second bias power is greater than the first bias power and the third bias power.

[0026] In some embodiments, the first pressure is 100 mTorr to 1 Torr.

[0027] The first bias power is 0W.

[0028] The second pressure is 10mTorr to 100mTorr.

[0029] The second bias power is 50W to 100W.

[0030] The third pressure is 1 Torr to 5 Torr.

[0031] The third bias power is 0W.

[0032] The fourth pressure is 30mTorr to 100mTorr.

[0033] The fourth bias power is 1000W to 2000W.

[0034] In some embodiments, the first fluorocarbon gas is any one of C4F8, C4F6, C5F8, CHF3, and CH2F2.

[0035] In some embodiments, the first inert gas is Ar.

[0036] In some embodiments, the second fluorocarbon gas is any one of C4F8, C4F6, C5F8, and CH3F.

[0037] In some embodiments, the third fluorocarbon gas is CF4.

[0038] In some embodiments, the first preset number of times is 1 time or 2 times.

[0039] In some embodiments, the second preset number of times is 10 to 30 times.

[0040] In some embodiments, when performing the deposition step, N2 is also added to the second fluorocarbon gas to enhance the polymer forming ability; the second fluorocarbon gas and N2 have the following flow ratio: C4F8:N2=1:8~1:10; or C4F6:N2=1:3~1:5; or C5F8:N2=1:3~1:5; or CH3F:N2=1:2~1:5.

[0041] In some embodiments, while performing the second processing step during the formation of the via, a third processing step is also performed simultaneously with the third etching step. The third processing step uses charged particles in the plasma of CF4 to perform a third treatment on the exposed surface of the mask, forming a third polymer layer on the exposed surface of the mask.

[0042] According to a second aspect of this application, embodiments of this application also provide a glass through-hole, which is obtained using the glass through-hole structure implementation method provided in any of the embodiments of the first aspect above.

[0043] The embodiments of this application may have, or at least have, the following advantages:

[0044] (1) By using a photoresist mask and an etching process including multiple periodic cyclic etching steps formed sequentially by a first etching step and a second etching step, the substrate of the glass material is etched. The substrate is isotropically etched using neutral particles in the plasma of the first gas (i.e., the plasma of the first gas after filtering out charged particles). A first polymer layer is formed on the inner wall of the formed via and on the mask. The first polymer layer on the bottom of the inner wall is anisotropically etched using charged particles in the plasma of the second gas (i.e., the plasma of the first gas is not ion filtered). The substrate below is exposed so that the first etching can be performed again. The selectivity of the mask can be significantly improved. Therefore, it is possible to replace the traditional metal hard mask with a photoresist mask to form vias (glass vias) with a higher aspect ratio on the substrate of the glass material. It can also improve the etching uniformity and verticality, avoid the contamination problem when using a metal mask, simplify the process, and improve efficiency.

[0045] (2) By first using neutral particles in the plasma of the first gas (a first carbon-fluorine gas with a carbon-fluorine ratio greater than or equal to 1:3) to perform isotropic first etching on the substrate in each cycle, and turning off the bias power (the first bias power is 0W), the bombardment of the mask can be reduced. At the same time as etching, the first polymer layer formed on the mask is used to protect the mask, which significantly improves the mask selectivity and forms an etched structure of a certain depth on the substrate. Then, under a certain bias power (the second bias power is 50W to 100W), charged particles in the plasma of the second gas (the first inert gas) are used to perform anisotropic second etching, which can open a new opening (the second opening). Thus, by performing the first etching again, the etching can continue downward. Therefore, the problem of difficulty in continuous downward etching caused by the isotropic etching in the previous step is eliminated. By repeating the first etching step and the second etching step, a via (glass via) is finally formed on the substrate. Therefore, a via structure with a higher aspect ratio and higher interconnect density that is difficult to achieve by conventional processes can be realized.

[0046] (3) By using a first carbon-fluorine gas with a carbon-fluorine ratio greater than or equal to 1:3 for the first etching, the high carbon-fluorine ratio can be used to enhance the polymer formation effect. At the same time as etching, a first polymer layer is formed on the inner wall and the exposed surface of the mask, thus playing a dual role of etching and protection. This not only allows for control of the degree of lateral etching, but also eliminates the independently set and indispensable deposition step in the traditional periodic etching process. Therefore, only one set of process gas (first gas) system is needed to complete the etching and deposition processes that originally required two sets of process gas (etching gas + deposition gas) systems, greatly simplifying the process, improving efficiency, and reducing control difficulty.

[0047] (4) By using Ar (second gas) for the second etching, the bottom of the inner wall of the forming via can be directionally bombarded to remove the first polymer layer on the bottom of the inner wall, exposing the substrate below for the first etching. At the same time, the characteristic that Ar has little effect on the substrate (compared to conventional etching gases such as fluorine-containing gases) can be taken advantage of to avoid damage to the formed etching morphology, prevent the upper size from increasing with repeated etching, ensure etching uniformity and verticality, and thus make it more conducive to realizing glass vias with higher aspect ratio and higher interconnect density that are difficult to achieve with conventional processes on the substrate.

[0048] (5) By performing a second processing step after or during the formation of the via, the via can have better sidewall smoothness, thus improving device performance. Specifically, when the second processing step is performed during the formation of the via, the etching rate and sidewall quality can be balanced by alternating the cyclical deposition and third etching steps with the etching process. This achieves high etching rate and high etching accuracy (atomic level accuracy) for high aspect ratio glass vias, effectively improves the uniformity and roughness of local polymers, solves the linewidth offset problem, achieves higher perpendicularity, and achieves better uniformity (uniform dimensions at the top, middle, and bottom positions of the glass via).

[0049] (6) When performing the deposition step, by using a plasma of a second fluorocarbon gas (third gas) with a carbon-fluorine ratio greater than or equal to 1:2, and under high pressure (third pressure) and off bias power (third bias power is 0W), a second polymer layer is deposited on the sidewall. This makes it easier for the second polymer layer to stay and accumulate on the sidewall surface of the recess between adjacent protrusions where the flow rate is relatively weak, preventing further lateral etching. However, very little is deposited on the sidewall surface at the end of the protrusion. Thus, when using a plasma of a third fluorocarbon gas (fourth gas) with a carbon-fluorine ratio less than 1:3, and performing the third etching step under low pressure (fourth pressure) and a large bias power (fourth bias power is 1000W~2000W), the flow rate of the etching gas can be increased and given directionality, so that the etching is mainly concentrated on the end of the protrusion. This not only effectively removes the protrusions on the sidewall, but also effectively protects the sidewall, which is beneficial to maintaining dimensional uniformity.

[0050] (7) By adding N2 to the second fluorocarbon gas (third gas), the polymer forming ability of the second fluorocarbon gas can be enhanced, so that the second fluorocarbon gas mainly exhibits the deposition effect and inhibits its etching effect, thereby improving the deposition efficiency and strengthening the protection of the sidewall.

[0051] (8) By using a second etching step included in the etching process as a first processing step before performing the etching process, and using charged particles in the plasma of the first inert gas to perform a first treatment on the surface of the mask, the surface roughness of the mask can be reduced, and the density and corrosion resistance of the first polymer layer deposited during the subsequent first etching step can be improved, thereby enhancing the protection capability of the mask and reducing mask consumption. Therefore, the selectivity of the mask can be further improved. Furthermore, by using charged particles in the plasma of CF4 used in the third etching step to perform a third treatment on the exposed surface of the mask, a third polymer layer can be formed on the exposed surface of the mask, which can also reduce the consumption rate of the photoresist material of the mask, thereby improving the selectivity. Therefore, by performing multiple treatments on the photoresist material mask, the surface quality and dimensional accuracy of the mask are effectively guaranteed. This not only significantly improves the selectivity of the mask, but also allows for the acquisition of more vertical sidewalls, which has a positive impact on the etching of glass vias with higher aspect ratios and higher interconnection densities.

[0052] Other advantages of this application will be described in the following detailed description. Attached Figure Description

[0053] Figure 1 This is a flowchart illustrating a preferred embodiment of a glass through-hole structure according to this application.

[0054] Figure 2 This is a schematic diagram of the structure after a mask is formed on a substrate, according to a preferred embodiment of this application.

[0055] Figure 3 This is a schematic diagram of the structure after forming a first intermediate via structure on a substrate, according to a preferred embodiment of this application.

[0056] Figure 4 This is a schematic diagram of a structure after a first second opening is formed on the bottom of a first intermediate through hole structure, according to a preferred embodiment of this application.

[0057] Figure 5 This is a schematic diagram of a structure after a second first intermediate through hole structure is formed below the first second opening, according to a preferred embodiment of this application.

[0058] Figure 6 This is a schematic diagram of a structure after a second polymer layer is formed on the sidewall and mask of a first intermediate through-hole structure, according to a preferred embodiment of this application.

[0059] Figure 7 This is a schematic diagram of a structure after the sidewall of the first intermediate through hole structure is processed to form the second intermediate through hole structure, which is a preferred embodiment of this application.

[0060] Figure 8 This is a schematic diagram of a structure after a second opening is formed on the bottom of a second intermediate through hole structure, according to a preferred embodiment of this application.

[0061] Figure 9 This is a schematic diagram of a structure after a first intermediate through-hole structure is formed below a second intermediate through-hole structure, according to a preferred embodiment of this application.

[0062] Figure 10 This is a schematic diagram of the structure after forming a through hole, provided in a preferred embodiment of this application.

[0063] Figure 11 This is a schematic diagram of the structure after removing the mask, provided as a preferred embodiment of this application.

[0064] In the figure: 10. Substrate; 11. First opening; 12. Mask; 13. First intermediate through-hole structure; 131. Second intermediate through-hole structure; 14. First polymer layer; 15. Second opening; 16. Second polymer layer; 17. Through-hole. Detailed Implementation

[0065] Existing through-glass via (TGV) etching processes typically use plasmas containing fluorine gases such as CF4 and SF6 to perform non-periodic cyclic etching of glass substrates. Because using gases with relatively weak polymer-forming capabilities like CF4 or SF6 for continuous one-step etching results in a low selectivity for the photoresist (primarily because these gases cannot provide sufficient polymer protection and the energetic ions in the plasma bombard the photoresist), making it difficult to etch very deep TGV structures. While using gases with stronger polymer-forming capabilities, such as C4F8 and C4F6, provides better protection for the photoresist, excessive polymer formation during non-periodic cyclic etching can cause etching angle deviations or even "etching stoppage." Therefore, from an etching perspective, existing TGV etching processes can only use gases with relatively weak polymer-forming capabilities, but this results in a low photoresist selectivity, necessitating the use of more resistant metal masks for TGV etching. Furthermore, the disadvantage of using non-periodic cyclic etching is that the dimensional uniformity of the TGV after etching is relatively poor (generally forming a shape that is larger at the top and smaller at the bottom), which affects the realization of extreme high aspect ratio etching, making it difficult to meet the growing demand for larger aspect ratios and higher interconnect densities.

[0066] To address the shortcomings of existing technologies, embodiments of this application provide a method for implementing a glass through-hole structure, including:

[0067] Provide a substrate made of glass material;

[0068] Multiple photoresist masks are formed on the surface of the substrate, with a first opening between two adjacent masks;

[0069] An etching process is performed to etch the substrate exposed in the first opening to form a through-hole on the substrate;

[0070] The etching process includes multiple periodic cyclic etching steps formed sequentially by a first etching step and a second etching step.

[0071] The first etching step uses neutral particles in the plasma of the first gas to perform isotropic first etching on the substrate and forms a first polymer layer on the inner wall of the forming via and the mask to protect the inner wall and the mask during the first etching.

[0072] The second etching step uses charged particles in the plasma of the second gas to perform anisotropic second etching on the first polymer layer on the bottom of the inner wall, forming a second opening on the bottom of the inner wall and exposing the substrate so that the first etching can be performed again through the second opening;

[0073] The first gas is a first carbon-fluorine gas with a carbon-fluorine ratio greater than or equal to 1:3, and the second gas is a first inert gas;

[0074] Before performing the etching process, the second etching step contained in the etching process is used as a first processing process. The first processing process uses charged particles in the plasma of the first inert gas to perform a first treatment on the surface of the mask to reduce the surface roughness.

[0075] In addition, a second processing step is performed to improve the smoothness of the sidewalls of the through hole.

[0076] This application embodiment employs a photoresist mask and an etching process including multiple periodic cyclic etching steps formed sequentially by a first etching step and a second etching step to etch a glass substrate. Neutral particles from a first gas plasma are used to perform isotropic first etching on the substrate, forming a first polymer layer on the inner wall of the forming via and on the mask. Charged particles from a second gas plasma are used to perform anisotropic second etching on the bottom of the first polymer layer on the inner wall, exposing the underlying substrate for further first etching. This significantly improves the mask selectivity, enabling the formation of vias (glass vias) with higher aspect ratios on glass substrates using a photoresist mask instead of a traditional hard metal mask. It also improves etching uniformity and perpendicularity, avoids contamination problems associated with metal masks, simplifies the process, and increases efficiency. Furthermore, by additionally using a second etching step as a first processing step before performing the etching process to treat the mask surface, the mask selectivity can be further improved. Furthermore, by performing a second processing step, better sidewall smoothness was achieved, improving device performance.

[0077] This application also provides a glass through-hole obtained using the above-described glass through-hole structure implementation method.

[0078] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0079] refer to Figure 1 This application provides a method for implementing a glass through-hole structure, which includes the following steps:

[0080] Step S11: Provide a substrate of glass material.

[0081] refer to Figure 2 A glass substrate 10 (glass substrate) is used to further form vias (through-glass vias (TGVs)) on the substrate 10 by performing an etching process.

[0082] In some embodiments, the via can be a high aspect ratio via (e.g., an aspect ratio greater than 50:1).

[0083] In some embodiments, the glass material includes SiO2, etc.

[0084] Step S12: Form multiple photoresist masks on the surface of the substrate and perform a first treatment on the surface of the masks.

[0085] refer to Figure 2In some embodiments, a spin-coating process can be used to form a photoresist layer on the upper surface of the substrate 10. Then, a photolithography process is used to etch the photoresist layer, thereby forming a plurality of photoresist patterns, i.e., photoresist material masks 12, on the upper surface of the substrate 10. Each pair of adjacent masks 12 has a first opening 11 for etching the substrate 10, and the bottom of the first opening 11 exposes the surface of the substrate 10 located between the two adjacent masks 12.

[0086] It should be noted that, Figure 2 The diagram only schematically illustrates the case where two masks 12 are formed on the upper surface of the substrate 10. However, it is understood that more masks, such as three masks, four masks, ten masks, etc., can be formed on the upper surface of the substrate 10, and the diagram is not limited to this.

[0087] In some embodiments, a first processing step may be performed before etching the substrate 10. Specifically, before performing the etching process, a second etching step contained in the etching process is additionally used as the first processing step. The first processing step includes using charged particles from the plasma of the first inert gas used in the second etching step to perform a first treatment on the surface of the mask 12 to reduce the surface roughness of the mask 12. By reducing the surface roughness of the mask 12, the density and etch resistance of the first polymer layer deposited on the surface of the mask 12 can be improved when the first etching step contained in the subsequent etching process is performed, thereby improving the protection capability of the mask 12, reducing the consumption of the mask 12 during the etching process, and thus further improving the selectivity of the mask 12. In other words, the first processing step is a pre-process independent of the etching process, formed by utilizing the second etching step contained in the etching process and reusing the second etching step before the etching process begins.

[0088] Step S13: Using neutral particles in the plasma of the first gas, an isotropic first etching is performed on the substrate, and a first polymer layer is formed on the inner wall of the forming via and on the mask.

[0089] In some embodiments, by performing an etching process and periodically etching the surface of the substrate 10 exposed in the first opening 11 between adjacent masks 12, a via (glass via) with a high aspect ratio is formed on the substrate 10.

[0090] The etching process includes multiple periodic cyclic etching steps formed by sequentially performing a first etching step and a second etching step. That is, by repeatedly performing the first etching step and the second etching step, multiple periodic cyclic etching steps are formed, performed sequentially by performing the first etching step and the second etching step. The first etching step is used to perform a first etching on the substrate 10 and to form a first polymer layer on the inner wall of the formed via (intermediate via structure) and on the entire exposed surface of the mask 12, so as to protect the inner wall of the formed via and the mask 12 during the first etching.

[0091] Therefore, the etching process in this application embodiment no longer includes the deposition step found in conventional periodic cyclic etching processes.

[0092] refer to Figure 3 In some embodiments, a first etching step in the etching process is performed, using a plasma of a first gas to which charged particles have been filtered out, i.e., using neutral particles in the plasma of the first gas, isotropically etching the exposed surface of the substrate 10 through a first opening 11 between adjacent masks 12, forming a first intermediate via structure 13 (the first first intermediate via structure 13) on the substrate 10. Simultaneously, taking advantage of the high polymer-forming properties of the first gas, a first polymer layer 14 is formed on the inner wall of the first intermediate via structure 13 (the via under formation) and on all exposed surfaces of the masks 12 (for emphasis, ...). Figure 3 Only the first polymer layer 14 located on the inner wall of the first intermediate via structure 13 and the top surface of the mask 12 is shown. The first polymer layer 14 deposited on other parts (such as the side surface of the mask 12 and the exposed bottom surface at the junction with the top of the first intermediate via structure 13) is omitted from the display. This is to protect the inner wall of the first intermediate via structure 13 and the mask 12 during the first etching step. In other words, in this embodiment, the first gas used in the first etching step is used both to etch the substrate 10 to form the first intermediate via structure 13 and to form the first polymer layer 14 to protect the inner wall of the first intermediate via structure 13 and the mask 12.

[0093] By ionizing the first gas introduced into the process chamber, a plasma of the first gas is obtained. The ion filtration function of the process chamber is then activated to remove charged particles such as ions from the plasma formed by the first gas, resulting in neutral particles. These neutral particles from the plasma are then used to perform an isotropic first etching on the substrate 10, forming a first intermediate via structure 13 on the substrate 10. Simultaneously, a first polymer layer 14 is formed on the inner wall of the first intermediate via structure 13 and on the surface of the mask 12.

[0094] In some embodiments, the first gas is a first fluorocarbon gas with a carbon-to-fluorine ratio greater than or equal to 1:3. For example, the first fluorocarbon gas can be any one of C4F8, C4F6, C5F8, CHF3, and CH2F2, and He (a second inert gas) can be used as an auxiliary gas. That is, fluorine radicals (neutral particles) in the plasma formed by the first fluorocarbon gas can be used, and He can be used as an auxiliary gas to perform the first etching and deposition of the first polymer layer 14 on the substrate 10.

[0095] In some embodiments, a first etching step is performed using a first temperature, a first pressure, a first source power, and a first bias power. Specifically, the first temperature is greater than 0°C, the first pressure is greater than the pressure used when performing the second etching step (second pressure), the first source power is greater than the source power used when performing the second etching step (second source power), and the first bias power is less than the bias power used when performing the second etching step (second bias power).

[0096] In some embodiments, the first temperature is 50°C to 90°C. For example, the first temperature can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C, or any value between any two of the aforementioned temperature values. However, it is not limited to this.

[0097] In some embodiments, the first pressure is 100 mTorr to 1 Torr. For example, the first pressure can be 100 mTorr, 200 mTorr, 300 mTorr, 400 mTorr, 500 mTorr, 600 mTorr, 700 mTorr, 800 mTorr, 900 mTorr, or 1 Torr, or any value between any two of the aforementioned pressure values. However, it is not limited to these.

[0098] In some embodiments, the first source power is 1000W to 3000W. For example, the first source power can be 1000W, 1200W, 1500W, 2000W, 2500W, or 3000W, or any value between any two of the aforementioned source power values. However, it is not limited to this.

[0099] In some embodiments, the first bias power is 0W (bias power off).

[0100] In some embodiments, the total flow rate of the first gas (including the first fluorocarbon gas and the auxiliary gas) is 50 sccm to 1000 sccm. For example, the total flow rate of the first gas can be 50 sccm, 60 sccm, 80 sccm, 100 sccm, 300 sccm, 500 sccm, 700 sccm, or 1000 sccm, or any value between any two of the aforementioned flow rate values. However, it is not limited to this.

[0101] In some embodiments, when the first fluorocarbon gas is any one of C4F8, C4F6, C5F8, CHF3, and CH2F2, and He is used as the auxiliary gas, the following flow ratios may be present: C4F8:He = 3:1 to 4:1; or, C4F6:He = 5:1 to 6:1; or, C5F8:He = 5:1 to 6:1; or, CHF3:He = 1:1 to 2:1; or, CH2F2:He = 2:1 to 3:1. However, the relationship is not limited to these.

[0102] This embodiment employs a photoresist mask 12 and uses plasma (neutral particles) containing a first gas to filter out charged particles for isotropic first etching of the substrate 10. The bias power is turned off (first bias power is 0W), reducing bombardment of the mask 12. The high carbon-to-fluorine ratio of the first gas enhances polymer formation. Simultaneously, a heavy first polymer layer 14 forms on the inner wall of the first intermediate via structure 13 and the exposed surface of the mask 12, providing excellent protection for the mask 12. This results in a high selectivity for the mask 12, achieving both etching and protection functions and expanding the process window. Furthermore, utilizing the non-directional nature of neutral particles, approximately 1:1 isotropic etching can be achieved in both the longitudinal and transverse directions, resulting in an etching morphology of the first intermediate via structure 13 that is nearly bowl-shaped (arc-shaped depression) (see reference). Figure 3 The first polymer layer 14, covering the inner wall of the first intermediate through-hole structure 13, prevents the first etching from continuing, thereby ensuring the uniformity of dimensions in each cycle. Therefore, the embodiments of this application can not only control the degree of lateral etching, but also eliminate the independently set and indispensable deposition step in the traditional periodic etching process. Only one set of process gas (first gas) system is needed to complete the etching and deposition processes that conventionally require two sets of process gas (etching gas + deposition gas) systems, greatly simplifying the process, improving efficiency, and reducing control difficulty.

[0103] Furthermore, by using the second etching step in the etching process as the first processing step, the surface of the mask 12 is treated to reduce the surface roughness of the mask 12, making it easier for the first polymer layer 14 to be uniformly deposited on the smooth surface of the mask 12, thus improving the deposition quality of the first polymer layer 14. Therefore, the density and corrosion resistance of the first polymer layer 14 deposited on the surface of the mask 12 can be improved, thereby improving the protection capability of the mask 12 and reducing the consumption of the mask 12 during the etching process, thereby further improving the selectivity of the mask 12.

[0104] Step S14: Using charged particles in the plasma of the second gas, perform anisotropic second etching on the first polymer layer at the bottom of the inner wall, and expose the substrate at the bottom, so as to perform a first etching on the exposed substrate again.

[0105] The second etching step in the etching process is used to perform anisotropic second etching on the first polymer layer 14 at the bottom of the inner wall of the forming via (first intermediate via structure 13), forming a second opening in the first polymer layer 14 at the bottom of the forming via, exposing the substrate 10 below the second opening so that the first etching can be performed again through the second opening. Thus, by repeating the first etching, downward etching can continue, eliminating the problem of difficulty in continuous downward etching caused by the isotropic etching in the previous step. By repeating the first and second etching steps multiple times, vias with higher aspect ratios that are difficult to achieve with conventional processes can be fabricated on the substrate 10.

[0106] refer to Figure 4 In some embodiments, a second etching step in the etching process is performed using a plasma of a second gas, specifically using charged particles in the plasma of the second gas, and anisotropically etching the first polymer layer 14 on the bottom of the formed first first intermediate via structure 13 through the first opening 11. This etching penetrates the first polymer layer 14 covering the bottom of the first first intermediate via structure 13, thereby forming a second opening 15 on the first polymer layer 14 at the bottom of the first first intermediate via structure 13, exposing the substrate 10 located below the second opening 15. Thus, the first etching can be performed again through the second opening 15, and a second first intermediate via structure 13 can be subsequently formed on the substrate 10 below the second opening 15 (below the first first intermediate via structure 13), as shown below the second opening 15. Figure 5 As shown. Similarly, through-holes with the desired depth and aspect ratio can be formed on substrate 10 (figure not shown).

[0107] By ionizing the second gas introduced into the process chamber, a plasma of the second gas is obtained; and the ion filtering function of the process chamber is turned off, i.e., the ion filtering is canceled, so that the ions contained in the plasma formed by the introduced second gas are retained, resulting in charged particles. The charged particles in the obtained plasma of the second gas can be used to perform a first treatment on the surface of the mask 12 before performing the etching process. Furthermore, during the etching process, the charged particles in the obtained plasma of the second gas can be used to perform isotropic first etching on the first polymer layer 14 at the bottom of the first first intermediate through-hole structure 13, and to form a through second opening 15 on the first polymer layer 14 at the bottom of the first first intermediate through-hole structure 13, such as... Figure 4 As shown.

[0108] In some embodiments, the second gas is a first inert gas. For example, the first inert gas may be Ar. That is, charged particles (Ar ions) in an Ar plasma are used to perform an isotropic first etching on the first polymer layer 14 at the bottom of the first intermediate via structure 13 to form a second opening 15. And the surface of the mask 12 is subjected to a first treatment using charged particles (Ar ions) in an Ar plasma.

[0109] In some embodiments, a second etching step is performed using a second temperature, a second pressure, a second source power, and a second bias power. Specifically, the second temperature is greater than 0°C (the second temperature may be the same as or different from the first temperature), the second pressure is less than the first pressure, the second source power is less than the first source power, and the second bias power is greater than the first bias power.

[0110] In some embodiments, the second temperature is 50°C to 90°C. For example, the second temperature can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C, or any value between any two of the aforementioned temperature values. However, it is not limited to these.

[0111] In some embodiments, the second pressure is 10 to 100 mTorr. For example, the second pressure can be 10 mTorr, 20 mTorr, 30 mTorr, 40 mTorr, 50 mTorr, 60 mTorr, 70 mTorr, 80 mTorr, 90 mTorr, or 100 mTorr, or any value between any two of the aforementioned pressure values. However, it is not limited to these.

[0112] In some embodiments, the second source power is 500W to 1000W. For example, the second source power can be 500W, 600W, 700W, 800W, 900W, or 1000W, or any value between any two of the aforementioned source power values. However, it is not limited to this.

[0113] In some embodiments, the second bias power is 50W to 100W. For example, the second bias power can be 50W, 60W, 70W, 80W, 90W, or 100W, or any value between any two of the aforementioned bias power values. However, it is not limited to this.

[0114] In some embodiments, the total flow rate of the second gas is 50 sccm to 1000 sccm. For example, the total flow rate of the second gas can be 50 sccm, 60 sccm, 90 sccm, 100 sccm, 200 sccm, 500 sccm, 800 sccm, or 1000 sccm, or any value between any two of the aforementioned flow rate values. However, it is not limited to this.

[0115] This embodiment of the application, by using a second gas to perform anisotropic second etching under a certain bias power (the second bias power is 50W to 100W), can not only directionally bombard the bottom of the inner wall of the forming via, removing the first polymer layer 14 on the bottom of the inner wall and exposing the substrate 10 below for the first etching, but also utilizes the characteristic that Ar has virtually no significant etching effect on the substrate 10 (compared to conventional etching gases such as fluorine-containing gases), avoiding damage to the already formed etching morphology and preventing the problem of the upper dimension continuously increasing with repeated etching, thus ensuring etching uniformity and verticality. This is more conducive to realizing etching structures (glass vias) with higher aspect ratios and higher interconnect density on the substrate 10 that are difficult to achieve with conventional processes.

[0116] The process conditions (temperature, pressure, source power, bias power, and second gas flow rate) when performing the first processing step can be the same as those when performing the second etching step.

[0117] Step S15: After each first etching operation with a first preset number of cycles, a second treatment is performed on the sidewalls of the formed via.

[0118] Due to the unique cyclic etching process of this application, after each execution of steps S13 to S14, i.e., after each consecutive execution of the first to second etching steps, serrated patterns (protrusions) will be regularly formed on the sidewalls of the forming via, and the serrated patterns have a certain degree of protrusion (nanometer level) (see reference). Figure 5 , Figure 9 Therefore, after each of the first etching steps in a periodic etching cycle of a first preset number of times, a second processing step is performed on the formed via to improve the smoothness of the sidewalls of the formed via, thereby improving the smoothness of the sidewalls of the finally formed via.

[0119] In some embodiments, the first preset number of times is 1 time or 2 times.

[0120] In some embodiments, a second processing step is performed to remove at least a portion of the serrations present on the sidewalls of the formed via (first intermediate via structure 13). The second processing step includes a deposition step and a third etching step; the deposition step uses charged particles in a plasma of a third gas to deposit a second polymer layer on the sidewalls of the formed via; the third etching step uses charged particles in a plasma of a fourth gas to remove a portion of the thickness of the second polymer layer deposited on the sidewalls and reacts with the substrate material on the exposed surface of the serrations on the sidewalls to remove at least a portion of the serrations.

[0121] refer to Figure 6 In some embodiments, by ionizing the third gas introduced into the process chamber to obtain a plasma of the third gas, and turning off the ion filtering function of the process chamber, i.e., canceling the ion filtering, a second polymer layer 16 is deposited on the sidewalls of the first first intermediate through-hole structure 13 and the second first intermediate through-hole structure 13 with the plasma containing charged particles of the third gas. (The second polymer layer 16 is also deposited on the mask 12, but for emphasis...) Figure 6 Only the second polymer layer 16 located on the inner wall of the first intermediate via structure 13 and the top surface of the mask 12 is shown. The deposited second polymer layer 16 will be located on the first polymer layer 14. By depositing the second polymer layer 16, the overall thickness of the polymer on the sidewalls can be adjusted, which not only protects the sidewalls but also lays the foundation for performing the third etching step.

[0122] Then, by ionizing the fourth gas introduced into the process chamber to obtain a plasma of the fourth gas, and turning off the ion filtering function of the process chamber (i.e., canceling the ion filtering), the plasma of the fourth gas containing charged particles removes a portion of the thickness of the second polymer layer 16 deposited on the sidewall (and may also remove a portion of the thickness of the first polymer layer 14 deposited on the sidewall), and reacts with the substrate material of the exposed serrated surface on the sidewall to remove at least part of the serrations. By repeating the deposition step and the third etching step sequentially multiple times, the serrations on the sidewall can be completely or substantially removed. After processing the sidewalls of the first first intermediate via structure 13 and the second first intermediate via structure 13, a second intermediate via structure 131 with smooth sidewalls is obtained, as shown below. Figure 7 As shown. On the sidewall of the second intermediate through-hole structure 131, there are still a second polymer layer 16 and a first polymer layer 14 of a certain thickness, which play a role in adjusting the thickness uniformity of the polymer on the sidewall, effectively preventing lateral etching, thereby ensuring the uniformity of dimensions.

[0123] Subsequently, by performing the second etching step in the second periodic etching step, a second second opening 15 is formed on the bottom of the second intermediate through-hole structure 131, that is, on the bottom of the second first intermediate through-hole structure 13 after sidewall treatment, as shown. Figure 8 As shown, after completing the entire second cycle etching step (after performing the second etching step in the second cycle etching step, there will be residue in both the second polymer layer 16 and the first polymer layer 14; for simplicity, this is not shown here), Figure 8 (And the second polymer layer 16 is omitted from the following figures).

[0124] In some embodiments, the third gas is a second fluorocarbon gas with a carbon-to-fluorine ratio greater than or equal to 1:2. For example, the second fluorocarbon gas may be any one of C4F8, C4F6, C5F8, and CH3F.

[0125] By using a second fluorocarbon gas with strong polymer-forming ability as the third gas, a second polymer layer 16 can be deposited on the sidewall to prevent the etching reaction from continuing, thereby protecting the sidewall from lateral etching and preventing the problem of size expansion.

[0126] In some embodiments, N2 is also added to the second fluorocarbon gas during the deposition step. Adding N2 to the second fluorocarbon gas enhances its polymer-forming ability, allowing the third gas to primarily function as a polymer deposition agent (forming CN polymers or CHN polymers, and spontaneously dissociating to generate C-containing polymers). This suppresses the etching effect of the second fluorocarbon gas, thereby improving deposition efficiency and strengthening sidewall protection.

[0127] In some embodiments, the fourth gas is a third fluorocarbon gas with a carbon-to-fluorine ratio of less than 1:3 and weak polymer-forming ability. For example, the third fluorocarbon gas can be CF4, and Ar (a third inert gas) can be used as an auxiliary gas. Using CF4, a portion of the thickness of the second polymer layer 16 on the sidewall can be removed, exposing the ends of the serrated texture, and it can react with the substrate material (SiO2) at the exposed area, thereby removing at least a portion of the serrated texture.

[0128] In some embodiments, when performing the second processing step, the deposition step and the third etching step are repeated in a second preset number of cycles (one cycle is defined as one consecutive execution of the deposition step and one third etching step).

[0129] In some embodiments, the second preset number of times is 10 to 30 times. For example, the second preset number of times can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 times. Alternatively, the second preset number of times can be less than 10 or more than 30 times (depending on the prominence of the serrated pattern).

[0130] In some embodiments, a high-pressure third pressure is used to perform the deposition step, and a low-pressure fourth pressure is used to perform the third etching step. The third pressure is greater than the first pressure, and the first pressure is greater than the second and fourth pressures. There are recesses between adjacent serrations on the sidewall. By using a high-pressure third pressure in the deposition step and turning off the bias power, the structural difference between the protruding ends of the serrations and the recesses on the sidewall allows the introduced third gas to more easily remain and accumulate on the sidewall surface at the recesses where the flow rate is relatively low. At the sidewall surface at the ends of the serrations, the flow rate of the third gas is relatively high, and the structure at the ends of the serrations is special, with relatively few polymer adhesion points. Therefore, at the ends of the serrations, the deposition of the second polymer layer 16 is minimal and thin. Since the use of the fourth gas consumes a portion of the second polymer layer 16 on the sidewalls, the flow rate of the fourth gas can be increased and directional by using a low-pressure fourth gas and applying a large bias power. This allows the etching to focus primarily on the ends of the serrated patterns (because firstly, there is less polymer deposited at the ends of the serrated patterns, and secondly, the consumption of polymer by the fourth gas exposes the ends of the serrated patterns). The relatively thick second polymer layer 16 on the sidewall surface of the recessed portion effectively protects the sidewalls during the third etching step.

[0131] In some embodiments, a third processing step is performed simultaneously with the third etching step. The third processing step uses charged particles from the plasma of CF4 (the fourth gas) used in the third etching step to treat the exposed surface of the mask 12, forming a third polymer layer (not shown) on the exposed surface of the mask 12. By forming the third polymer layer on the exposed surface of the mask 12, the consumption rate of the photoresist material in the mask 12 can also be reduced, thereby improving the selectivity.

[0132] Therefore, by performing multiple treatments (first treatment, third treatment) on the photoresist mask 12, the surface quality and dimensional accuracy of the mask 12 are effectively guaranteed. This not only significantly improves the selectivity of the mask 12, but also enables the acquisition of more vertical sidewalls, which has a positive impact on the etching of glass vias with higher aspect ratios and higher interconnect density.

[0133] In some embodiments, a third temperature, a third pressure, a third source power, and a third bias power are used to perform the deposition step.

[0134] In some embodiments, the third temperature is 10°C to 20°C. For example, the third temperature can be 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, or 20°C, or any value between any two of the aforementioned temperature values. However, it is not limited to this.

[0135] In some embodiments, the third pressure is 1 Torr to 5 Torr. For example, the third pressure can be 1 Torr, 1.3 Torr, 1.5 Torr, 1.7 Torr, 2 Torr, 3 Torr, 4 Torr, or 5 Torr, or any value between any two of the aforementioned pressure values. However, it is not limited to these values.

[0136] In some embodiments, the third source power is 100W to 500W. For example, the third source power can be 100W, 200W, 300W, 400W, or 500W, or any value between any two of the aforementioned source power values. However, it is not limited to this.

[0137] In some embodiments, the third bias power is 0W (bias power off).

[0138] In some embodiments, the total flow rate of the third gas (including the second fluorocarbon gas and N2) is 100 sccm to 500 sccm. For example, the total flow rate of the third gas can be 100 sccm, 200 sccm, 300 sccm, 400 sccm, or 500 sccm, or any value between any two of the aforementioned flow rate values. However, it is not limited to this.

[0139] In some embodiments, when the third gas is any one of C4F8, C4F6, C5F8, and CH3F, and N2 is added, the following flow ratios may be used: C4F8:N2 = 1:8 to 1:10; or C4F6:N2 = 1:3 to 1:5; or C5F8:N2 = 1:3 to 1:5; or CH3F:N2 = 1:2 to 1:5. However, this is not a limitation.

[0140] In some embodiments, a third etching step is performed using a fourth temperature, a fourth pressure, a fourth source power, and a fourth bias power.

[0141] In some embodiments, the fourth temperature is 10°C to 20°C. For example, the fourth temperature can be 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, or 20°C, or any value between any two of the aforementioned temperature values. However, it is not limited to this.

[0142] In some embodiments, the fourth pressure is 30 to 100 mTorr. For example, the fourth pressure can be 30, 40, 50, 60, 70, 80, 90, or 100 mTorr, or any value between any two of the aforementioned pressure values. However, it is not limited to this.

[0143] In some embodiments, the fourth source power is 100W to 1000W. For example, the fourth source power can be 100W, 200W, 300W, 400W, 500W, 600W, 700W, 800W, 900W, or 1000W, or any value between any two of the aforementioned source power values. However, it is not limited to this.

[0144] In some embodiments, the fourth bias power is 1000W to 2000W. For example, the fourth bias power can be 1000W, 1100W, 1200W, 1300W, 1400W, 1500W, 1600W, 1700W, 1800W, 1900W, or 2000W, or any value between any two of the aforementioned bias power values. However, it is not limited to this.

[0145] In some embodiments, the total flow rate of the fourth gas (including CF4 and Ar) is 50 sccm to 200 sccm. For example, the total flow rate of the fourth gas can be 50 sccm, 60 sccm, 80 sccm, 100 sccm, 120 sccm, 150 sccm, 170 sccm, or 200 sccm, or any value between any two of the aforementioned flow rate values. However, it is not limited to this.

[0146] In some embodiments, when the fourth gas is CF4 and Ar is used as the auxiliary gas, the following flow ratio may be used: CF4:Ar = 1:5 to 1:10. However, it is not limited to this.

[0147] Step S16: Repeat steps S13 to S15 until a via is formed on the substrate.

[0148] refer to Figure 9 In some embodiments, in Figure 8 Based on the structure shown, step S13 is repeated, that is, the first etching step of the third periodic cyclic etching step in the etching process is repeated. Neutral particles in the plasma of the first gas are used, with mask 12 as a mask, and the substrate 10 exposed below the second second opening 15 is etched isotropically again through the first opening 11 and the second second opening 15 (located on the bottom of the second intermediate through-hole structure 131). A third first intermediate through-hole structure 13 is then formed on the substrate 10 below the second second opening 15 (below the second intermediate through-hole structure 131). At the same time, taking advantage of the strong polymer forming ability of the first gas, a first polymer layer 14 is formed on the inner wall of the third first intermediate through-hole structure 13 (including the second intermediate through-hole structure 131) and all exposed surfaces of the mask 12.

[0149] Next, the above step S14 is repeated, that is, the second etching step of the third periodic cyclic etching step in the etching process is repeated. Charged particles in the plasma of the second gas are used, with mask 12 as a mask, and through the first opening 11 and the second second opening 15, anisotropic second etching is performed on the first polymer layer 14 on the bottom of the third first intermediate through-hole structure 13, and the first polymer layer 14 covering the bottom of the third first intermediate through-hole structure 13 is etched through, thereby forming a second opening 15 (the third second opening 15) on the first polymer layer 14 at the bottom of the third first intermediate through-hole structure 13, exposing the substrate 10 located below the second opening 15.

[0150] Similarly, by continuing to repeat steps S13 to S14, a fourth first intermediate through-hole structure 13 can be formed below the third first intermediate through-hole structure 13, and so on. Figure 9 As shown. And after one or two first intermediate through-hole structures 13 are formed below the second intermediate through-hole structure 131, the second processing process is performed once.

[0151] Finally, through-holes 17 with a target aspect ratio and smooth sidewalls, consisting of a plurality of first intermediate through-hole structures 13 with sidewall treatment (second treatment), are formed from top to bottom on the glass substrate 10, as shown in the figure. Figure 10 As shown.

[0152] By alternating cycles of deposition and third etching steps with the etching process, the etching rate and sidewall quality are balanced, thereby achieving high etching rate and high etching precision (atomic level precision) for high aspect ratio glass vias. This effectively improves the uniformity and roughness of local polymers, solves the linewidth offset problem, achieves higher perpendicularity, and achieves better uniformity (uniform dimensions at the top, middle, and bottom positions of high aspect ratio glass vias), better sidewall smoothness, and improves device performance.

[0153] It should be noted that during the last cycle (the last periodic etching step) before the formation of the through-hole 17, since it is no longer necessary to form a second opening 15 at the bottom of the last first intermediate through-hole structure 13, the second etching step can be omitted (by default) during the last cycle. That is, after the bottommost first intermediate through-hole structure 13 is formed and the second processing is performed, a second opening 15 no longer needs to be formed at the bottom of the bottommost first intermediate through-hole structure 13.

[0154] In some embodiments, the etching process based on multiple periodic cyclic etching steps in this application includes only the first etching step and the second etching step described above in sequence, and no longer includes other etching steps for etching the substrate 10 and other deposition steps for independently depositing the first polymer layer 14 (the second processing process is an independent process embedded in the etching process).

[0155] In some embodiments, the etching process includes a first etching stage, a second etching stage, and a third etching stage, which are sequentially connected and used to form the top, middle, and bottom portions of a via, respectively. Furthermore, the carbon-to-fluorine ratio of the first fluorocarbon gas used in the first etching step of the first etching stage, the carbon-to-fluorine ratio of the first fluorocarbon gas used in the first etching step of the second etching stage, and the carbon-to-fluorine ratio of the first fluorocarbon gas used in the first etching step of the third etching stage increases sequentially.

[0156] Furthermore, the carbon-to-fluorine ratio of the second fluorocarbon gas used in the deposition step of the second processing step executed in the first etching stage, the carbon-to-fluorine ratio of the second fluorocarbon gas used in the deposition step of the second processing step executed in the second etching stage, and the carbon-to-fluorine ratio of the second fluorocarbon gas used in the deposition step of the second processing step executed in the third etching stage increase sequentially.

[0157] For example, in the first etching stage, the first gas used in the first etching step can be a first carbon-fluorine gas with a carbon-fluorine ratio of 1:3, such as CHF3; in the second etching stage, the first gas used in the first etching step can be a first carbon-fluorine gas with a carbon-fluorine ratio of 1:2, such as C4F8 or CH2F2; in the third etching stage, the first gas used in the first etching step can be a first carbon-fluorine gas with a carbon-fluorine ratio greater than 1:2, such as C4F6 or C5F8.

[0158] Similarly, in the first etching stage, the third gas used in the deposition step can be a second fluorocarbon gas with a carbon-to-fluorine ratio of 1:2, such as C4F8; in the second etching stage, the third gas used in the deposition step can be a second fluorocarbon gas with a carbon-to-fluorine ratio greater than 1:2 and less than 1:1, such as C4F6 or C5F8; in the third etching stage, the third gas used in the deposition step can be a second fluorocarbon gas with a carbon-to-fluorine ratio of 1:1, such as CH3F. Alternatively, CH4 can also be used.

[0159] Thus, as the etching depth of the via increases during formation, a higher carbon-to-fluorine ratio enhances deposition, effectively suppressing lateral etching of the sidewall bottom and eliminating bottom side-cutting issues. This further ensures dimensional uniformity and perpendicularity along the depth direction. Therefore, by performing the etching process in stages, not only are the limitations of traditional single etching processes in achieving high-precision control overcome, but a more refined and controllable etching scheme is also provided for the fabrication of high-performance devices. This effectively expands the etching process window, facilitating the realization of glass vias with higher aspect ratios and higher interconnect densities.

[0160] In some embodiments, a second processing step may be performed after the through-hole is formed to treat the sidewalls of the formed through-hole. For example, it may be possible to... Figure 5 Based on the structure shown, by performing the second etching step in the second periodic cyclic etching step, a second second opening is formed on the first polymer layer 14 at the bottom of the second first intermediate via structure 13, completing the entire second periodic cyclic etching step. By repeating steps S13 and S14, a third first intermediate via structure, a fourth first intermediate via structure, and so on, are continuously formed below the second first intermediate via structure until a via with the desired aspect ratio is formed from top to bottom on the substrate, consisting of successive first intermediate via structures. Then, by sequentially performing the deposition step in the second processing step and the second preset number of times in the third etching step, the serrations on the sidewalls of the formed via can be simultaneously treated, completely or substantially removing the serrations, thus obtaining a via with smoother sidewalls (see reference). Figure 10 Please refer to the second treatment described above for the forming through-hole for further understanding.

[0161] Step S17: Remove the mask.

[0162] refer to Figure 11 In some embodiments, a plasma of a fifth gas is used to remove the mask 12 from the surface of the substrate 10. The plasma of the fifth gas is obtained by ionizing the fifth gas introduced into the process chamber. After removing the mask 12, a via 17, i.e., a through-glass via (TGV), is formed on the surface of the substrate 10.

[0163] In some embodiments, the fifth gas includes an oxidizing gas. For example, the fifth gas may include O2, etc.

[0164] According to a second aspect of this application, embodiments of this application also provide a glass through-hole, which is obtained using the glass through-hole structure implementation method provided in any of the embodiments of the first aspect above.

[0165] refer to Figure 11In some embodiments, the glass via (TGV) is a via 17. The via 17 is formed on the surface of the glass substrate 10 (glass substrate) and undergoes a sidewall treatment (second treatment) to further improve the sidewall smoothness.

[0166] In some embodiments, the substrate 10 having glass through-holes (through-holes 17) can be applied to fields such as high-frequency communication, optoelectronics, 3D integration and advanced packaging.

[0167] In a third aspect, embodiments of this application also provide a plasma processing apparatus for performing the glass via structure implementation method corresponding to the above embodiments to form the via 17 (glass via) corresponding to the above embodiments. The plasma processing apparatus includes inductively coupled plasma (ICP) etching equipment or capacitively coupled plasma (CCP) etching equipment, etc.

[0168] In other aspects, embodiments of this application also provide an electronic device, including a glass through-hole (through-hole 17) obtained using the glass through-hole structure implementation method of the above embodiments. The electronic device can be a storage device, mobile phone, computer, tablet computer, electronic instrument, television, artificial intelligence device, etc.

[0169] In summary, this embodiment employs a photoresist mask 12 and uses neutral particles from a first gas plasma to perform isotropic first etching on the surface of the glass substrate 10 exposed in the first opening 11 between two adjacent masks 12. A first polymer layer 14 is formed on the inner wall of the forming via and on the mask 12. Charged particles from a second gas plasma are used to perform anisotropic second etching on the first polymer layer 14 at the bottom of the inner wall to form a second opening 15, exposing the substrate 10 below. This allows for another first etching through the second opening 15. This significantly improves the selectivity of the mask 12, enabling the replacement of traditional metal hard masks with photoresist masks 12. By sequentially repeating the first and second etching steps, vias 17 (glass vias) with a higher aspect ratio can be formed on the substrate 10. Furthermore, it improves etching uniformity and verticality, avoids contamination problems associated with using metal masks, simplifies the process, and increases efficiency. Furthermore, by performing a second etching step, which is part of the etching process, as a first processing step before the etching process, the surface of the mask 12 is first treated, which further improves the selectivity of the mask 12. And by performing the second processing step, better sidewall smoothness is achieved, thus improving device performance.

[0170] The above are merely preferred embodiments of this application. These embodiments are not intended to limit the scope of protection of this application. Therefore, any equivalent changes made based on the description and drawings of this application should also be included within the scope of protection of this application.

Claims

1. A method of implementing a glass via structure, the method comprising: The method comprises: providing a substrate of glass material; forming a plurality of masks of photoresist material on a surface of the substrate, with a first opening between any two adjacent masks; performing an etching process to etch the substrate exposed in the first opening to form a via on the substrate; wherein the etching process comprises a plurality of periodic cycles of first etching step and second etching step; the first etching step uses neutral particles in plasma of a first gas to perform isotropic first etching on the substrate, and forms a first polymer layer on the inner wall of the via being formed and the mask to protect the inner wall and the mask during the first etching; the second etching step uses charged particles in plasma of a second gas to perform anisotropic second etching on the first polymer layer on the inner wall bottom to form a second opening on the inner wall bottom and expose the substrate to perform the first etching again through the second opening; the first gas is a first fluorocarbon gas with a fluorine-carbon ratio greater than or equal to 1:3, and the second gas is a first inert gas; before performing the etching process, a first processing process is performed using the second etching step contained in the etching process, which uses charged particles in plasma of the first inert gas to perform first processing on the surface of the mask to reduce surface roughness; and, a second processing process is performed to improve the smoothness of the sidewall of the via.

2. The method of claim 1, wherein, After the via is formed, the second processing process is performed to perform second processing on the sidewall of the formed via; or during the formation of the via, the second processing process is performed once after each first preset number of first etching steps are completed to perform second processing on the sidewall of the via being formed.

3. The method of claim 2, wherein, The second processing process comprises a deposition step and a third etching step; the deposition step uses charged particles in plasma of a third gas to deposit a second polymer layer on the sidewall, and the third etching step uses charged particles in plasma of a fourth gas to remove a portion of the thickness of the second polymer layer deposited on the sidewall and react with the substrate material present and exposed on the protrusion surface of the sidewall to remove at least part of the protrusion; wherein the third gas is a second fluorocarbon gas with a fluorine-carbon ratio greater than or equal to 1:2, and the fourth gas is a third fluorocarbon gas with a fluorine-carbon ratio less than 1:3; when the second processing process is performed, the deposition step and the third etching step are sequentially repeated for a second preset number of times.

4. The method of claim 3, wherein, The first etching step is performed using a first pressure and a first bias power, the second etching step is performed using a second pressure and a second bias power, the deposition step is performed using a third pressure and a third bias power, and the third etching step is performed using a fourth pressure and a fourth bias power, the third pressure being greater than the first pressure, the first pressure being greater than the second pressure and the fourth pressure, the fourth bias power being greater than the second bias power, and the second bias power being greater than the first bias power and the third bias power.

5. The method of claim 4, wherein, The first pressure is 100 mTorr to 1 Torr; and / or, the first bias power is 0 W; and / or, the second pressure is 10 mTorr to 100 mTorr; and / or, the second bias power is 50 W to 100 W; and / or, the third pressure is 1 Torr to 5 Torr; and / or, the third bias power is 0 W; and / or, the fourth pressure is 30 mTorr to 100 mTorr; and / or, the fourth bias power is 1000 W to 2000 W.

6. The method of claim 3, wherein, The first fluorocarbon gas is any one of C4F8, C4F6, C5F8, CHF3, and CH2F2; and / or, the first inert gas is Ar; and / or, the second fluorocarbon gas is any one of C4F8, C4F6, C5F8, and CH3F; and / or, the third fluorocarbon gas is CF4.

7. The method of claim 3, wherein the glass via structure is formed by a method comprising: The first preset number of times is 1 or 2; and / or, the second preset number of times is 10 to 30.

8. The method of claim 3, wherein, When performing the deposition step, N2 is further added to the second fluorocarbon gas to enhance polymer formation capability; the second fluorocarbon gas and N2 have the following flow rate ratio relationship: C4F8:N2 = 1:8 to 1:10; or C4F6:N2 = 1:3 to 1:5; or C5F8:N2 = 1:3 to 1:5; or CH3F:N2 = 1:2 to 1:

5.

9. The method of claim 6, wherein, When performing the second processing process in the process of forming the via, a third processing process is performed at the same time as performing the third etching step, the third processing process using charged particles in a CF4 plasma to perform third processing on the exposed surface of the mask to form a third polymer layer on the exposed surface of the mask.

10. A glass via, characterized by, The glass via structure is obtained by using the implementation method of any one of claims 1 to 9.

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