Substrate surface treatment method

Abstract

The invention relates to a substrate surface treatment method, which comprises the following steps of: planarizing the surface of a substrate; and performing a plasma treatment step on the surface of the substrate, wherein the planarization treatment step and the plasma treatment step are performed on the surface of the substrate asynchronously in an adjustable order. The substrate surface treatment method can solve a plurality of technical problems caused by a traditional single process or a synchronous composite process.

Description

Technical Field

[0001] This invention relates to a processing method, and more particularly to a substrate surface treatment method. Background Technology

[0002] In the development of advanced semiconductor manufacturing processes, especially 3D integrated circuits (3D ICs), the quality of the substrate surface has become a core indicator determining the performance and yield of the final product. Advanced technologies such as hybrid bonding require extremely high flatness and cleanliness of the substrate surface to achieve defect-free direct chip-to-chip connections.

[0003] To achieve the aforementioned standards, the most commonly used key technology in the industry is planarization processing steps such as Chemical Mechanical Polishing (CMP). However, such planarization techniques have physical limitations. While they can achieve macroscopic planarization of the substrate, they also create microscopic defects on the substrate surface, such as micro-scratches or sub-surface damage. These microscopic defects caused by planarization processes directly compromise the integrity of subsequent hybrid bonding interfaces, thereby affecting hybrid bonding strength and electrical performance.

[0004] To address the lack of a single planarization step, the industry has attempted to integrate plasma technology, which provides an ion bombardment effect, into the planarization process, such as plasma-assisted chemical mechanical polishing (CMP). However, this integrated process only provides plasma during the CMP step, resulting in a complex process architecture that significantly increases equipment costs and control difficulty. Furthermore, the in-situ generated plasma is difficult to precisely control. In addition, the plasma in this type of technology removes contaminants through the bombardment effect of high-energy ions. Moreover, this physical impact method undoubtedly causes new physical damage to the substrate surface, potentially increasing its surface roughness.

[0005] Therefore, it is evident that neither using planarization alone nor integrating planarization with plasma technology can achieve the required surface roughness of the substrate. Thus, achieving the required surface roughness of the substrate remains a critical technological bottleneck that urgently needs to be overcome. Summary of the Invention

[0006] In view of this, one or more objectives of the present invention is to provide a substrate surface treatment method to solve many problems of the above-mentioned conventional technology.

[0007] To achieve the aforementioned objective, the present invention provides a substrate surface treatment method comprising the following steps: performing a planarization process on a surface of a substrate; and performing a plasma treatment on the surface of the substrate, wherein the planarization process and the plasma treatment are performed on the surface of the substrate in an adjustable order rather than simultaneously.

[0008] The planarization process and the plasma source process are applied alternately and cyclically to the surface of the substrate according to an adjustable sequence, wherein the adjustable sequence is selected from a group consisting of sequential and reverse sequences.

[0009] The surface roughness of the substrate after the planarization and plasma treatment steps is different from the initial surface roughness of the substrate.

[0010] The surface roughness of the substrate after the planarization and plasma treatment steps is reduced by at least 20% compared to the surface roughness of the substrate after only the planarization or plasma treatment steps.

[0011] The surface roughness of the substrate after the planarization and plasma treatment steps is reduced by at least 50% compared to the surface roughness of the substrate after only the planarization or plasma treatment steps.

[0012] The number of scratches or the total length of scratches obtained after the planarization process and the plasma process on the surface of the substrate are reduced compared to the number of scratches or the total length of scratches obtained after only the planarization process or the plasma process on the surface of the substrate.

[0013] The initial surface roughness of the substrate, the surface roughness obtained after the planarization process and the plasma process, and / or the surface roughness obtained after only the planarization process or the plasma process are calculated using arithmetic mean roughness, root mean square roughness, or ten-point mean roughness.

[0014] The plasma used in this plasma processing step is a remote plasma, and the remote plasma is generated by a remote plasma source (RPS).

[0015] The remote plasma source is coupled to a processing chamber for performing the plasma processing step on the substrate using the remote plasma in the processing chamber.

[0016] The remote plasma source includes a reactor, and the plasma processing step involves reacting a gas in the reactor to generate the remote plasma.

[0017] The gas contains one or more substances selected from the group consisting of: fluorinated compounds, wherein the fluorinated compounds are nitrogen trifluoride (NF3), carbon tetrafluoride (CF4), hexafluoroethane (C2F6) or octafluoropropane (C3F8); argon (Ar); oxygen (O2); and nitrogen (N2).

[0018] The plasma used in this plasma treatment step is capacitively coupled plasma, microwave plasma, direct current (DC) plasma, or laser-induced plasma.

[0019] The capacitively coupled plasma is generated by a capacitively coupled plasma source at a radio frequency.

[0020] The microwave plasma is generated by a microwave plasma source at frequencies above 900MHz.

[0021] The plasma used in the plasma treatment step is used to perform an annealing process on the substrate simultaneously with the plasma treatment step on the surface of the substrate.

[0022] The plasma used in the plasma treatment step is applied to the surface of the substrate by non-ionic bombardment.

[0023] In this plasma treatment step, the plasma used reacts with the substrate in the form of at least one active particle.

[0024] The active particles react with the surface of the substrate by non-ionic bombardment.

[0025] The planarization process is either a grinding process or a polishing process.

[0026] The grinding process involves grinding with a grinding wheel or lapping with a grinding fluid.

[0027] The grinding process involves grinding the substrate on one side or both sides.

[0028] The polishing process involves a combination of a coarse polishing step and a fine polishing step on the surface of the substrate, thereby giving the surface of the substrate corresponding surface roughness.

[0029] The polishing process involves either chemical mechanical polishing (CMP) or diamond mechanical polishing (DMP).

[0030] The polishing process involves polishing the substrate on one or both sides.

[0031] The planarization process involves processing one surface of the substrate and the other surface opposite to it with different process parameters.

[0032] The planarization process involves treating one surface of the substrate and the other surface opposite to it with different removal rates.

[0033] The substrate surface treatment method further includes using an auxiliary fluid to assist in treating the surface of the substrate during the planarization step.

[0034] The auxiliary fluid is ozone and / or ozone water.

[0035] The auxiliary fluid contains chemicals selected from the group consisting of EKC class chemicals, hydrochloric acid, hydrogen peroxide, sulfuric acid, hydrofluoric acid, and ammonia.

[0036] The auxiliary fluid is a grinding slurry selected from the group consisting of silica, alumina, zirconium oxide, titanium oxide, cerium oxide and silicon carbide.

[0037] The process includes a cleaning step on the surface of the substrate before and / or after the planarization step and / or the plasma treatment step.

[0038] The substrate surface treatment method further includes a heating step or a cooling step, used in conjunction with the planarization step or the cleaning step to treat the surface of the substrate.

[0039] The substrate surface treatment method further includes a heating step or a cooling step, used in conjunction with the planarization step to treat the surface of the substrate.

[0040] The substrate surface treatment method further includes an ultrasonic oscillation step to generate ultrasonic waves to treat the surface of the substrate in conjunction with the planarization step or the cleaning step.

[0041] The substrate surface treatment method further includes an ultrasonic vibration step to generate an ultrasonic wave to treat the surface of the substrate in conjunction with the planarization step.

[0042] The cleaning or flattening process further includes the use of ozone water, which enhances the cleaning or flattening efficiency through the cavitation effect generated by the ultrasonic waves in the ultrasonic oscillation process.

[0043] The cleaning process further includes the use of SPM solution, HF solution, SC-1 solution and / or SC-2 solution.

[0044] The cleaning process further includes using a brush to scrub the surface of the substrate.

[0045] The substrate is selected from a group consisting of silicon, gallium arsenide, indium phosphide, silicon carbide, gallium nitride, and gallium oxide.

[0046] The substrate is classified as an N-type substrate, a P-type substrate, an insulating substrate, or a semi-insulating substrate.

[0047] The process includes a material generation step following the cleaning step, which generates a material layer on the substrate, wherein the material layer is the same as, partially the same as, or different from the material of the substrate.

[0048] The cleaning process is followed by an epitaxial growth step to generate an epitaxial layer on the substrate.

[0049] The substrate contains insulating or non-insulating materials.

[0050] The substrate contains either metallic or non-metallic materials.

[0051] The substrate carries logic circuits, radio frequency circuits, and / or memory circuits.

[0052] In this process, the substrate undergoes a planarization process and a plasma process to perform a bonding process with another substrate.

[0053] In this process, the substrate undergoes a planarization step and a plasma treatment step to perform a hybrid bonding process with another substrate.

[0054] The substrate is used to form a CoWoS (chip-on-wafer-on-substrate) structure, a CoPoS (Chip-on-Panel-on-Substrate) structure, and / or a SoIC (system-on-integrated-chips) structure by performing the hybrid bonding process with the other substrate.

[0055] In this process, the substrate improves the yield of the hybrid bonding process between the substrate and the other substrate by performing the planarization process and the plasma process.

[0056] The adjustable order is selected from groups composed of sequential and reverse orders.

[0057] As described above, the substrate surface treatment method of the present invention has one or more advantages or technical effects:

[0058] (1) The present invention overcomes the defects of a single process and achieves a multiplier effect by performing planarization and plasma processing steps on the substrate separately and not simultaneously. It also avoids the control difficulties and potential damage caused by performing planarization and plasma processing steps at the same time.

[0059] (2) The plasma treatment step of the present invention provides active particles to replace the traditional ion bombardment technology, which can avoid new physical damage during the repair process of the plasma-treated substrate, and can also effectively reduce the number of scratches or the total length of scratches on the substrate surface.

[0060] (3) After performing the planarization and plasma treatment steps separately, the surface roughness of the substrate can be reduced by at least about 20%, and even by about 50%.

[0061] (4) The substrate surface treatment method of the present invention performs planarization treatment and plasma treatment steps separately, and the order of processing can be flexibly adjusted. For example, it can be performed sequentially or in reverse order, and even cyclically, the planarization treatment and plasma treatment steps can be performed on the surface of the substrate. Each cycle is based on the previous cycle to meet different substrate materials, surface quality requirements or other process or product requirements.

[0062] (5) The present invention can achieve a smooth and defect-free substrate surface, and realize high-density three-dimensional integrated circuits (3D ICs) by implementing a hybrid bonding process. Moreover, it can significantly improve the success rate and bonding quality of subsequent hybrid bonding, thereby improving process yield and product reliability.

[0063] To enable you to have a better understanding of the technical features and effects of this invention, preferred embodiments and detailed descriptions are provided below. Attached Figure Description

[0064] Figures 1 to 5 The diagram illustrates different processing sequences in the first preferred embodiment of the substrate surface treatment method of the present invention, wherein... Figure 1The planarization and plasma processing steps are shown in sequence. Figure 2 The planarization process is shown to be performed in reverse order of the plasma processing process. Figure 3 The planarization and plasma processing steps are shown to be performed alternately and cyclically. Figure 4 The planarization and plasma processing steps are shown to be performed alternately in reverse order. Figure 5 The planarization and plasma processing steps are shown to be performed alternately in sequence and in reverse order.

[0065] Figure 6 A schematic diagram illustrating the process of processing a substrate using the substrate surface treatment method of the present invention is shown, wherein... Figure 6 (A) is the flattening process. Figure 6 (B) is the plasma treatment step.

[0066] Figure 7 A flowchart illustrating a second preferred embodiment of the substrate surface treatment method of the present invention is shown.

[0067] Figure 8 A flowchart illustrating a third preferred embodiment of the substrate surface treatment method of the present invention is shown.

[0068] Explanation of reference numerals in the attached figures:

[0069] 10: Substrate

[0070] 12: Surface

[0071] 14: Another surface

[0072] 20: Remote Plasma Source

[0073] 30: Processing Room

[0074] S10: Flattening Process Steps

[0075] S20: Plasma treatment steps

[0076] S30: Cleaning Processing Steps

[0077] S40: Material Generation Steps

[0078] S50: Epitaxial wafer formation steps

[0079] S60: Bonding process Detailed Implementation

[0080] To facilitate understanding of the technical features, content, advantages, and effects of this invention, the invention is described in detail below with reference to accompanying drawings and embodiments. The drawings used are for illustrative purposes only and do not necessarily represent the actual scale and precise configuration of the invention. Therefore, the scale and configuration of the accompanying drawings should not be used to interpret or limit the scope of the invention in actual implementation. Furthermore, for ease of understanding, the same elements in the following embodiments are indicated by the same symbols.

[0081] Furthermore, unless otherwise specified, the terms used throughout this specification and claims generally have their ordinary meaning in the context of this art, the disclosure herein, and the specific content. Certain terms used to describe the invention will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the invention.

[0082] The use of terms such as "first," "second," "third," and "fourth" in this document does not specifically refer to any order or sequence, nor is it intended to limit the invention. Rather, it is merely used to distinguish components or operations described using the same technical terms.

[0083] Secondly, when this article uses terms such as "contains", "includes", "has", or "contains", these are all open-ended terms, meaning that they include but are not limited to.

[0084] First preferred embodiment:

[0085] The substrate surface treatment method of this invention is an asynchronous composite substrate surface treatment method to solve many problems of conventional technologies, such as surface defects, contaminant residues, poor adhesion of subsequent components, difficulty in control, or potential damage caused by single surface treatment steps and synchronous composite surface treatment steps. The substrate surface treatment method of this invention performs planarization and plasma treatment steps asynchronously, and the processing order can be adjusted according to different substrate materials and surface quality requirements. For example, the planarization and plasma treatment steps can be performed sequentially and / or in reverse order, and even alternately and cyclically. This invention can not only plasma treat the planarized substrate surface, but also planarize the plasma-treated substrate surface, thereby obtaining a substrate surface with excellent physical and chemical properties, significantly improving the yield and performance of semiconductor products.

[0086] Please see Figures 1 to 6In a first preferred embodiment, the substrate surface treatment method of the present invention includes the following steps: a planarization step S10 on the surface 12 of the substrate 10 and a plasma treatment step S20 on the surface 12 of the substrate 10, wherein the planarization step S10 and the plasma treatment step S20 are performed on the surface 12 of the substrate 10 in an adjustable order, not simultaneously. The adjustable order is selected from a sequence (e.g., ...) Figure 1 (as shown) and reverse order (as shown) Figure 2 The ethnic groups (as shown) constitute the group. Figure 1 For example, the substrate surface treatment method of the present invention first planarizes the surface 12 of the substrate 10, and then treats the planarized surface 12 of the substrate 10 with plasma, for example, to repair the surface 12 of the substrate 10 by plasma treatment. By performing a planarization treatment step S10 followed by a plasma treatment step S20, the present invention helps to modify, soften, or repair the surface 12 of the substrate 10, and can chemically repair micro-defects that may be introduced by the planarization treatment step S10, thereby reducing the total length of scratches and substantially not generating new physical damage. Figure 2 For example, the substrate surface treatment method of the present invention first treats the surface 12 of the substrate 10 with plasma, and then plans the surface 12 of the plasma-treated substrate 10. The present invention first modifies, softens, or repairs the surface 12 of the substrate 10 with plasma treatment step S20, which helps to reduce the physical processing difficulty of the subsequent planarization step S10 and reduces surface damage generated during planarization. The aforementioned adjustable sequence depends on actual needs, for example, it can be adjusted according to various requirements such as different substrate materials and surface quality requirements, to achieve, for example, the desired target surface roughness of the substrate 10 and / or subsequent applications. Furthermore, the aforementioned modification methods include changing the substrate 10 itself, or by adding external materials, so that the surface 12 of the modified substrate 10 has a different composition from the original substrate 10 or forms a structure, layer, or thin film different from the surface 12 of the original substrate 10.

[0087] In addition, the substrate surface treatment method of the present invention can selectively and alternately (or repeatedly) perform the planarization treatment step (S10) and the plasma treatment step (S20) on the surface 12 of the substrate 10 in an adjustable order. For example, the planarization treatment step (S10) and the plasma treatment step (S20) of the present invention can be performed alternately and cyclically in sequence (e.g. Figure 3 As shown), it is performed in a reverse alternating cyclical manner (such as...). Figure 4 (as shown) or proceed in a sequential and reverse alternating cyclical manner (such as...) Figure 5 (As shown). Figure 3For example, the steps of the substrate surface treatment method of the present invention are, in sequence, planarization step (S10), plasma treatment step (S20), planarization step (S10), plasma treatment step (S20), ..., and so on. Similarly, taking... Figure 4 For example, the sequence of steps in the substrate surface treatment method of the present invention is as follows: plasma treatment step (S20), planarization treatment step (S10), plasma treatment step (S20), planarization treatment step (S10), ..., and so on. The present invention, through the above-described cyclic mode, can progressively repair the surface 12 of the substrate 10 to meet more stringent surface quality requirements. The substrate surface treatment method of the present invention (e.g.) Figures 3 to 5 By employing iterative planarization and plasma treatment steps, the surface of substrate 10 can achieve a planarity effect far superior to any single surface treatment step or simultaneous composite surface treatment step. In other words, in the substrate surface treatment method of this invention, each cycle progressively reduces the surface roughness and defect density of the substrate surface based on the previous cycle. Therefore, compared to performing a single planarization step, this invention can significantly reduce surface roughness or progressively approach the target surface roughness. Furthermore, in another application, this invention can selectively perform each step of the substrate surface treatment method, for example, through real-time monitoring and feedback control. For instance, after completing the planarization step S10, a real-time monitoring module can be used to measure the surface roughness of the surface 12 of substrate 10 in real time. This allows the control component (such as a microprocessor controller) to automatically adjust the processing parameters of the subsequent plasma treatment step S20 based on the surface roughness measurement data. For example, it can extend the processing time, increase the concentration of active particles, or adjust the substrate temperature to improve the selectivity of the active particles for the substrate's reaction, thereby obtaining the desired target surface roughness. Alternatively, after completing the plasma processing step S20, the aforementioned real-time monitoring module is used to measure the surface roughness of the substrate 10 surface 12 in real time, so that the aforementioned control component can automatically adjust the processing parameters of the subsequent planarization processing step S10 based on the surface roughness measurement data, thereby obtaining the desired target surface roughness.

[0088] The substrate surface treatment method of the present invention is applicable to various substrates 10 used in the semiconductor field. The material of the substrate 10 is selected from, for example, a group consisting of silicon (Si), gallium arsenide (GaAs), indium phosphide (InP), silicon carbide (SiC), gallium nitride (GaN), and gallium oxide (Ga2O3). The substrate 10 may be, for example, a bulk substrate or an engineered substrate, such as a silicon-on-insulator (SOI) substrate, or an epitaxial substrate (e.g., a gallium nitride-on-silicon (GaN-on-Si) substrate) containing at least one epitaxial layer. The substrate 10 itself may contain insulating or non-insulating materials, or metallic or non-metallic materials, and may be an N-type, P-type, insulating, or semi-insulating substrate. Furthermore, prior to the substrate surface treatment method of the present invention, the substrate 10 may selectively, for example but not limited to, already have logic circuits, radio frequency circuits, and / or memory circuits mounted on it. However, the present invention is not limited to the above examples; the substrate 10 of the present invention may also selectively have other components or any circuits mounted on it, or may be a blank substrate without any components formed thereon.

[0089] In the substrate surface treatment method of the present invention, the planarization step S10 is, for example, a grinding step or a polishing step. The grinding step is, for example, grinding with a grinding wheel or lapping with polishing fluid, and the polishing step is, for example, chemical mechanical polishing (CMP) or diamond mechanical polishing (DMP). For example, the polishing step may polish the substrate 10 on one side or both sides, that is, polishing a single surface (such as surface 12 as described above) or two surfaces (such as surface 12 and surface 14 as described above) of the substrate 10. The grinding step may be, for example, grinding the substrate 10 on one side or both sides. The grinding step may be, for example, a combination of a coarse grinding step and a fine grinding step, so that the surface 12 of the substrate 10 has corresponding surface roughness. For example, the present invention can, for example, gradually reduce the surface roughness of the substrate 10 or obtain the desired surface roughness by using a grinding process of coarse-to-fine, fine-to-coarse, or alternating coarse-to-fine.

[0090] In the dual-surface treatment configuration, the present invention is not limited to using the same processing method to process the surface 12 (e.g., the front side) and the other surface 14 (e.g., the back side) of the substrate 10 respectively. The present invention can also selectively use different processing methods, such as using different process parameters or different removal rates to process the surface 12 (e.g., the front side) and the other surface 14 (e.g., the back side) of the substrate 10 respectively.

[0091] To improve processing efficiency or effectiveness, the planarization step S10 may further include the use of an auxiliary fluid. This auxiliary fluid may be, for example, but not limited to, ozone and / or ozonated water, used to clean or passivate the surface 12 of the substrate 10, or even soften the surface 12 of the substrate 10. Ozone and / or ozonated water can remove photoresist, metal ions, particles, and post-CMP defects. Ozone can be used alone or in combination with other auxiliary fluids. For example, the auxiliary fluid may also be a chemical comprising a group selected from EKC-type chemicals, hydrochloric acid, hydrogen peroxide, sulfuric acid, hydrofluoric acid, and ammonia. For example, EKC-type chemicals are suitable for precision cleaning of residues after photoresist stripping or etching. Inorganic acids and bases (e.g., hydrochloric acid (HCl), sulfuric acid (H2SO4), hydrofluoric acid (HF), and ammonia (NH4OH)) are suitable for etching metal or dielectric layers. Oxidizing agents (e.g., hydrogen peroxide (H₂O₂)) can be used, for example, in combination with acids or bases to accelerate the reaction rate. In chemical mechanical polishing processes, auxiliary fluids can also be used, for example, as slurries, achieving planarization through a synergistic effect of chemical action and mechanical polishing. The composition of the slurry is, for example, but not limited to, selected from the group consisting of silica, alumina, zirconium oxide, titanium oxide, cerium oxide, and silicon carbide. The pH value of the slurry of this invention can be determined according to actual needs and is not limited to a specific value; the pH value of the slurry can, for example, be greater than, equal to, or less than 7.

[0092] Furthermore, according to the substrate surface treatment method of the present invention, when performing the planarization process step S10, a heating step or a cooling step of the substrate 10 may be selectively included, so as to assist the operation of the planarization process step S10 by raising or lowering the temperature of the substrate 10, or an ultrasonic oscillation step may be selectively included, so as to assist the planarization process of the substrate 10 by generating ultrasonic waves.

[0093] In the substrate surface treatment method of the present invention, the plasma treatment step S20 performs plasma treatment on the surface 12 of the substrate 10 (i.e., the surface to be subsequently subjected to or already subjected to the planarization treatment step S10) to, for example, repair, modify, or soften the surface 12 of the substrate 10. The plasma used in the plasma treatment step S20 may be, for example, but not limited to, remote plasma generated by a remote plasma source 20 (RPS), or may be generated by a non-remote plasma source. The remote plasma source 20 is, for example, coupled to a processing chamber 30 via a transmission line to perform plasma treatment on the substrate 10 in the processing chamber 30. The remote plasma source 20 may include, for example, a reactor, in which at least one gas is reacted (e.g., excited) in the plasma treatment step S20 to generate remote plasma. In addition, the plasma used in the plasma processing step S20 of the present invention may also be generated by a non-remote plasma source, for example, wherein the plasma may be generated by reacting (e.g., being excited) the aforementioned gas.

[0094] The aforementioned gas may include, for example but not limited to, one or more substances selected from the group consisting of: fluorine-containing compounds [e.g., nitrogen trifluoride (NF3), carbon tetrafluoride (CF4), hexafluoroethane (C2F6) or octafluoropropane (C3F8)]; argon (Ar); oxygen (O2); and nitrogen (N2).

[0095] The aforementioned plasma can be, for example, but not limited to, capacitively coupled plasma, microwave plasma, direct current (DC) plasma, or laser-induced plasma. If it is capacitively coupled plasma, it can be generated from a capacitively coupled plasma source at a radio frequency, for example, configured at 13 MHz or higher. If it is microwave plasma, it can be generated from a microwave plasma source at a frequency of 900 MHz or higher. For example, the present invention can, for example, use microwaves or radio frequencies to dissociate the aforementioned gas (such as nitrogen trifluoride (NF3)) into a high-density plasma containing ions, electrons, and active particles (e.g., neutral active free radicals).

[0096] In the plasma treatment step S20 of the substrate surface treatment method of the present invention, the plasma (e.g., remote plasma) is preferably applied to the surface 12 of the substrate 10 by non-ion bombardment. Specifically, in the plasma treatment step S20, the plasma reacts with the substrate 10 using at least one active particle (e.g., free radical, rather than charged ions), and the active particles provided by the plasma of the present invention react with the surface 12 of the substrate 10 by non-ion bombardment, thereby repairing surface defects by chemical reaction rather than the physical impact method used in conventional plasma technology, thus avoiding secondary damage to the substrate 10. The present invention uses active particles in the plasma to react with the substrate 10 instead of conventional ion bombardment technology, thus avoiding secondary damage to the substrate 10 and significantly reducing the need for subsequent reprocessing. The present invention does not particularly limit the activity range, type, or concentration of the active particles mentioned above; as long as they can react with the substrate 10, such as through a chemical reaction, they are applicable to the present invention. Furthermore, in one feasible embodiment, when the substrate surface treatment method of the present invention performs plasma treatment on the surface 12 of the substrate 10 in the plasma treatment step S20, it can also simultaneously perform annealing treatment on the substrate 10.

[0097] Although plasma is an ionized gas composed of charged and neutral particles, the plasma of this invention treats the substrate 10 using non-ionic bombardment, such as chemical reactions, thus avoiding physical sputtering or lattice damage caused by high-energy ion bombardment. This invention can, for example, utilize neutral reactive species in the plasma, such as free radicals, to chemically treat the surface 12 of the substrate 10, while minimizing physical damage caused by high-energy charged ions. To achieve this, the following technical approaches can be used: (a) Remote Plasma Source (RPS): This is a preferred embodiment. By spatially separating the plasma generation area from the substrate treatment area, during transport, short-lived charged ions recombine with electrons at the transport tube wall and decay, ultimately only long-lived neutral reactive particles reach the surface 12 of the substrate 10. (b) Physical Shielding: A grounded grid or Faraday cage is placed above the substrate 10 to effectively neutralize or block charged ions while allowing neutral active particles to penetrate, achieving physical shielding against ion bombardment. (c) Downstream or Afterglow Treatment: The substrate is placed in the afterglow region downstream of the main glow discharge region. In this region, plasma density and ion energy are significantly reduced, making the treatment mechanism primarily chemical, while the physical bombardment effect is greatly weakened. (d) Pulsed Plasma: A time-separated strategy is employed, using periodic rapid switching of the power supply. During the afterglow period when the power is off, the ion bombardment energy drops sharply, allowing the remaining active particles to continue reacting with the substrate, thereby achieving a chemically reaction-driven treatment over time.

[0098] Second preferred embodiment:

[0099] Please see Figure 7 Please refer to the following as well. Figures 1 to 6 The technical difference between the second preferred embodiment of the present invention and the first preferred embodiment lies in that the substrate surface treatment method of the second preferred embodiment of the present invention adds a cleaning step S30, such as... Figure 7 As shown. Figure 7The step sequence of the substrate surface treatment method of the present invention is planarization step S10, plasma treatment step S20, and cleaning step S30 as an example, but it is not limited thereto. The present invention may optionally include a cleaning step S30 on the surface 12 of the substrate 10 before and / or after performing planarization step S10 and / or plasma treatment step S20.

[0100] To remove different types of contaminants, the cleaning process S30 of this invention can employ one or a combination of various industry-standard wet cleaning methods, selectively supplemented by mechanical action. The cleaning process S30 can optionally use an auxiliary fluid. This auxiliary fluid can be, for example, but not limited to, ozone and / or ozonated water. Ozone and / or ozonated water have functions such as substrate (e.g., wafer) cleaning, photoresist removal, and surface passivation, and can even soften the surface 12 of the substrate 10 or eliminate defects generated by chemical mechanical polishing (CMP) steps. Ozone can be used alone or in combination with other auxiliary fluids, which include chemicals selected from the group consisting of EKC-type chemicals, hydrochloric acid, hydrogen peroxide, sulfuric acid, hydrofluoric acid, and ammonia. For example, EKC-type chemicals are suitable for precision cleaning of residues after photoresist stripping or etching. Inorganic acids and bases (such as hydrochloric acid (HCl), sulfuric acid (H2SO4), hydrofluoric acid (HF), and ammonia (NH4OH)) can be used, for example, for etching metals or dielectric layers. Oxidizing agents (such as hydrogen peroxide (H2O2)) can be used, for example, in combination with acids or bases to accelerate the reaction rate. Compared to traditional RCA processes, ozone water wastewater treatment costs are lower, and ozone water is recyclable and uses less water, making it more environmentally friendly and offering the same or even better results. For example, if ozone water is used as the auxiliary fluid, it can remove hydrocarbon contaminants and metal ions from the wafer surface, particularly showing significant effects on Cu removal. The aforementioned metal ions are, for example, but not limited to, those selected from the group consisting of copper, iron, titanium, calcium, nickel, cerium, vanadium, cadmium, manganese, cobalt, zirconium, and aluminum ions. The pH value of ozone water can be determined according to actual needs and is not limited to a specific value; the pH value of ozone water can be, for example, greater than, equal to, or less than 7. Ozone water can effectively strip various photoresists, and its stripping efficiency is high under optimized conditions. Ozone water offers energy-saving benefits and maintains high stripping efficiency at lower temperatures. Ozone water can passivate the surface of substrates (such as wafers), reducing contamination of the wafer in the air and decreasing surface roughness, thus improving the integrity of the gate oxide layer. Furthermore, the passivated oxide has fewer voids, a smoother interface, and better quality. Since ozone dissolves in water (such as deionized water) to form ozone water, the concentration can be easily and stably adjusted using, for example, an ozone generator. The ozone water technology used in this invention employs ozonated deionized water (DIO3) for cleaning. Ozone oxidizes metal ions, transforming them into a less sticky state or compounds that can be removed by rinsing. The metal ions are then removed by subsequently using a mild acid to remove these compounds.

[0101] Furthermore, the cleaning step S30 can also utilize, for example but not limited to, SPM (Sulfuric Peroxide Mixture) solution, HF (Hydrofluoric Acid) solution, SC-1 (Standard Clean 1) solution, and / or SC-2 (Standard Clean 2) solution. The SPM solution, for example, uses a mixture of sulfuric acid and hydrogen peroxide at 120°C to 150°C to remove organic residues. The HF solution, for example, is used at room temperature to etch the oxide layer and remove metal contaminants. The SC-1 solution uses ammonia and hydrogen peroxide to remove fine dust particles. The SC-2 solution uses a mixture of hydrochloric acid and hydrogen peroxide at 70°C to 90°C to remove metal ions. The cleaning step S30 of this invention can also be used with brushes (e.g., brushes of various types and materials) to scrub the surface 12 of the substrate 10. The type and material of the brushes can also be changed or adjusted, for example, depending on the concentration of ozone water or other cleaning chemicals. To improve cleaning and / or planarization efficiency, the present invention may selectively include a heating or cooling step in conjunction with planarization step S10 or cleaning step S30 to planarize or clean the surface 12 of substrate 10. Alternatively, it may selectively include an ultrasonic oscillation step to generate ultrasonic waves in conjunction with planarization step S10 or cleaning step S30 to planarize or clean the surface 12 of substrate 10. The present invention utilizes the high-frequency acoustic energy applied by the ultrasonic waves in the ultrasonic oscillation step to induce a cavitation effect in the ozone water, thereby improving cleaning efficiency. Similarly, the planarization step S10 may also selectively utilize ozone water, using the high-frequency acoustic energy applied by the ultrasonic waves in the ultrasonic oscillation step to induce a cavitation effect in the ozone water, thereby improving planarization efficiency. Furthermore, the cleaning step S30 may be selectively combined with a single-wafer rotary cleaning device, a tank-type immersion cleaning device, or a wet rotary spray cleaning device to clean substrate 10 by rotation.

[0102] In the first and second preferred embodiments, the substrate surface treatment method of the present invention can significantly improve the quality of the surface 12 of the substrate 10 by performing planarization step S10 and plasma treatment step S20 separately. The surface roughness of the substrate 10 after treatment is different from the initial surface roughness of the untreated substrate 10, for example, the surface roughness can be increased or decreased. Specifically, taking the reduction of surface roughness as an example, compared with performing only a single planarization process or a single plasma treatment, the surface roughness of the present invention can be reduced by at least about 20% after performing planarization step S10 and plasma treatment step S20 separately, and can be reduced by about 50% under optimized conditions. At the same time, the number of scratches or the total length of scratches obtained after the substrate 10 treatment is reduced compared with the number of scratches or the total length of scratches obtained after a single planarization process or a single plasma treatment, and the reduction is significant. The surface roughness of the substrate 10 of the present invention is obtained by calculation, for example, but not limited to, using arithmetic mean roughness (Ra), root mean square roughness (Rq), or ten-point mean roughness (Rz).

[0103] Third preferred embodiment:

[0104] Please see Figure 8 Please refer to the following as well. Figures 1 to 7 ,like Figure 8 As shown, after performing planarization step S10, plasma treatment step S20, and cleaning step S30 on the substrate 10 according to the first preferred embodiment or the second preferred embodiment, the substrate surface treatment method of the present invention can also perform subsequent processes as needed, such as performing a material generation step S40 to generate a material layer on the substrate 10, or performing an epitaxial generation step S50 to grow new crystals on the substrate 10, i.e., generating an epitaxial layer. The material of the aforementioned material layer may be the same as, partially the same as, or different from the material of the substrate 10.

[0105] For example, the substrate surface treatment method of the present invention can prepare substrate 10 through the aforementioned planarization step S10, plasma treatment step S20, and cleaning step S30, thereby giving substrate 10 a clean surface (e.g., an ultra-smooth, defect-free surface) for bonding with another substrate in a bonding process S60. The bonding process S60 is, for example, but not limited to, a hybrid bonding process. Because the substrate surface treatment method of the present invention can give substrate 10 a clean surface, the yield of the aforementioned bonding process (e.g., the hybrid bonding process) can be significantly improved. Substrate 10 is not limited to a chip or wafer, and the other substrate is not limited to a chip or wafer; substrate 10 and the other substrate are not limited to being the same or different from each other. This hybrid bonding process can be used, for example, but not limited to, forming CoWoS (chip-on-wafer-on-substrate) structures, CoPoS (Chip-on-Panel-on-Substrate) structures, and / or SoIC (system-on-integrated-chips) structures. Furthermore, in another application, after the substrate 10 has a clean surface, the present invention can selectively perform a surface passivation step, for example, using hydrogen plasma, to form a layer of hydrogen terminals on the surface of the substrate 10. This can protect the surface 12 of the substrate 10 from re-contamination or oxidation by the atmospheric environment before it is transferred to the next process (such as bonding process S60), thereby ensuring the success rate and reliability of subsequent processes.

[0106] In summary, the substrate surface treatment method of the present invention has one or more of the following advantages:

[0107] (1) The present invention overcomes the defects of a single process and achieves a multiplier effect by performing planarization and plasma processing steps on the substrate separately and not simultaneously. It also avoids the control difficulties and potential damage caused by performing planarization and plasma processing steps at the same time.

[0108] (2) The plasma treatment step of the present invention provides active particles to replace the traditional ion bombardment technology, which can avoid new physical damage during the repair process of the plasma-treated substrate, and can also effectively reduce the number of scratches or the total length of scratches on the substrate surface.

[0109] (3) After performing the planarization and plasma treatment steps separately, the surface roughness of the substrate can be reduced by at least about 20%, and even by about 50%.

[0110] (4) The substrate surface treatment method of the present invention performs planarization treatment and plasma treatment steps separately, and the order of processing can be flexibly adjusted. For example, it can be performed sequentially or in reverse order, and even cyclically, the planarization treatment and plasma treatment steps can be performed on the surface of the substrate. Each cycle is based on the previous cycle to meet different substrate materials, surface quality requirements or other process or product requirements.

[0111] (5) The present invention can achieve a smooth and defect-free substrate surface, and realize high-density three-dimensional integrated circuits (3D ICs) by implementing a hybrid bonding process. Moreover, it can significantly improve the success rate and bonding quality of subsequent hybrid bonding, thereby improving process yield and product reliability.

[0112] The above description is merely illustrative and not restrictive. Any equivalent modifications or alterations made without departing from the spirit and scope of this invention should be included in the appended claims.

Claims

1. A substrate surface treatment method characterized by, comprising the steps of: performing a planarization process on a surface of a substrate; and performing a plasma treatment on the surface of the substrate with a plasma, wherein the planarization process and the plasma treatment are performed on the surface of the substrate in an adjustable sequence.

2. The method of claim 1, wherein the substrate surface is treated by a method selected from the group consisting of: wherein the planarization process and the plasma treatment are alternately and cyclically performed on the surface of the substrate according to the adjustable sequence, and the adjustable sequence is selected from a group consisting of a sequence and a reverse sequence. ​ 3. The method of claim 1, wherein the substrate surface is treated by a method selected from the group consisting of: wherein the surface roughness of the surface of the substrate after performing the planarization process and the plasma treatment is different from the initial surface roughness of the surface of the substrate. ​ 4. The method of claim 2, wherein the substrate surface is treated by a method selected from the group consisting of: wherein the surface roughness of the surface of the substrate after performing the planarization process and the plasma treatment is reduced by at least 20% compared to the surface roughness of the surface of the substrate after performing only the planarization process or the plasma treatment. ​ 5. The substrate surface treatment method as described in claim 2, characterized in that, wherein the surface roughness of the surface of the substrate after performing the planarization process and the plasma treatment is reduced by at least 50% compared to the surface roughness of the surface of the substrate after performing only the planarization process or the plasma treatment.

6. The method of claim 1, wherein the substrate surface is a semiconductor wafer. wherein the number of scratches or the total length of scratches of the surface of the substrate after performing the planarization process and the plasma treatment is reduced compared to the number of scratches or the total length of scratches of the surface of the substrate after performing only the planarization process or the plasma treatment.

7. The substrate surface treatment method according to claim 3, 4 or 5, wherein wherein the initial surface roughness of the surface of the substrate, the surface roughness of the surface of the substrate after performing the planarization process and the plasma treatment, and / or the surface roughness of the surface of the substrate after performing only the planarization process or the plasma treatment is calculated using an arithmetic average roughness, a root mean square roughness, or a ten-point average roughness.

8. The method of claim 1, wherein the substrate surface is a semiconductor wafer.

8. The method of claim 1, wherein the substrate surface is a semiconductor wafer. wherein the plasma used in the plasma treatment is a remote plasma, and the remote plasma is generated from a remote plasma source.

9. The substrate surface treatment method according to claim 8, wherein wherein the remote plasma source is coupled to a processing chamber for performing the plasma treatment on the substrate in the processing chamber with the remote plasma.

10. The substrate surface treatment method according to claim 9, wherein wherein the remote plasma source comprises a reactor, and the plasma treatment causes at least one gas to react in the reactor to generate the remote plasma.

11. The substrate surface treatment method according to claim 10, wherein wherein the gas comprises one or more species selected from a group consisting of: a fluorine-containing compound, wherein the fluorine-containing compound is nitrogen trifluoride, carbon tetrafluoride, hexafluoroethane, or octafluoropropane; argon; oxygen; and nitrogen.

12. The substrate surface treatment method according to claim 1 or 10, wherein wherein the plasma used in the plasma treatment is a capacitively coupled plasma, a microwave plasma, a direct current plasma, or a laser-induced plasma.

13. The substrate surface treatment method according to claim 12, wherein wherein the capacitively coupled plasma is generated from a capacitively coupled plasma source at a radio frequency.

14. The method of claim 12, wherein the substrate surface is treated by a method comprising: wherein the microwave plasma is generated from a microwave plasma source at a frequency above 900 MHz.

15. The method of claim 1 or 8, wherein wherein the plasma performs an annealing treatment on the substrate simultaneously with performing the plasma treatment on the surface of the substrate.

16. The method of claim 1 or 8, wherein wherein the plasma performs the plasma treatment on the surface of the substrate in a non-ion bombardment manner.

17. The method of claim 1 or 8, wherein wherein the plasma reacts the surface of the substrate with at least one active particle in the plasma treating step.

18. The method of claim 17, wherein the substrate surface is a semiconductor wafer. 19 wherein the active particle reacts the surface of the substrate in a non-ion bombardment manner.

19. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 19 wherein the planarization treating step is a grinding treating step or a polishing treating step.

20. The method of claim 19, wherein the substrate surface is a semiconductor wafer. wherein the grinding treating step is a grinding with a grinding wheel or a grinding with a grinding liquid.

21. The method of claim 20, wherein the substrate surface is a semiconductor wafer. 20 wherein the grinding treating step is a single side grinding or a double side grinding of the substrate.

22. The method of claim 20, wherein the substrate surface is a semiconductor wafer. wherein the grinding treating step is a combination of a coarse grinding step and a fine grinding step of the surface of the substrate, so as to have a corresponding surface roughness of the surface of the substrate.

23. The method of claim 19, wherein the substrate surface is a semiconductor wafer. 23 wherein the polishing treating step is a chemical mechanical polishing or a diamond mechanical polishing.

24. The substrate surface treatment method of claim 23, wherein wherein the polishing treating step is a single side polishing or a double side polishing of the substrate.

25. The substrate surface treating method of claim 19, wherein the planarization treating step treats the surface of the substrate and another surface opposite to the surface with different process parameters.

26. The method of claim 19, wherein the substrate surface is a semiconductor wafer. wherein the planarization treating step treats the surface of the substrate and another surface opposite to the surface with different removal rates.

27. The substrate surface treatment method as described in claim 19, characterized in that, further comprising using an auxiliary fluid to assist in treating the surface of the substrate in the planarization treating step.

28. The method of claim 27, wherein the substrate surface is a semiconductor wafer. 5 wherein the auxiliary fluid is ozone and / or ozone water.

29. The method of claim 27, wherein the substrate surface is treated by a method comprising: wherein the auxiliary fluid comprises a chemical selected from a group consisting of EKC chemicals, hydrochloric acid, hydrogen peroxide, sulfuric acid, hydrofluoric acid, and ammonia water.

30. The method of claim 27, wherein the substrate surface is a semiconductor wafer. wherein the auxiliary fluid is a slurry selected from a group consisting of silica, alumina, zirconia, titania, ceria, and silicon carbide.

31. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 30 wherein before and / or after the planarization treating step and / or the plasma treating step, further comprising a cleaning treating step of the surface of the substrate.

32. The method of claim 31, wherein the substrate surface is a semiconductor wafer. further comprising a heating step or a cooling step to treat the surface of the substrate in conjunction with the planarization treating step or the cleaning treating step.

33. The substrate surface treatment method as described in claim 1, characterized in that, further comprising a heating step or a cooling step to treat the surface of the substrate in conjunction with the planarization treating step.

34. The method of claim 31, wherein the substrate surface is a semiconductor wafer. further comprising an ultrasonic oscillation step to generate an ultrasonic wave to treat the surface of the substrate in conjunction with the planarization treating step or the cleaning treating step.

35. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 35 further comprising an ultrasonic oscillation step to generate an ultrasonic wave to treat the surface of the substrate in conjunction with the planarization treating step.

36. The substrate surface treatment method according to claim 34 or 35, wherein wherein the cleaning treating step or the planarization treating step further comprises using an ozone water to improve a cleaning efficiency or a planarization efficiency by a cavitation effect of the ultrasonic wave generated by the ultrasonic oscillation step.

37. The method of claim 36, wherein the substrate surface is treated by a method comprising: wherein the cleaning treating step further comprises using an SPM solution, an HF solution, an SC-1 solution, and / or an SC-2 solution.

38. The method of claim 36, wherein the substrate surface is a semiconductor wafer. 5 wherein the cleaning treating step further comprises using a brush to brush the surface of the substrate.

39. The substrate surface treatment method as described in claim 1, characterized in that, wherein the substrate is selected from a group consisting of silicon, gallium arsenide, indium phosphide, silicon carbide, gallium nitride, and gallium oxide.

40. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 5 wherein the substrate is an N-type substrate, a P-type substrate, an insulating substrate, or a semi-insulating substrate.

41. The method of claim 31, wherein the substrate surface is a semiconductor wafer. 5 wherein after the cleaning treating step, further comprising a material generating step to generate a material layer on the substrate, wherein the material layer is of the same material, partially the same material, or a different material from the substrate.

42. The method of claim 31, wherein the substrate surface is a semiconductor wafer. 5 wherein after the cleaning process step, a epitaxial formation step is further included for forming an epitaxial layer on the substrate.

43. The substrate surface treatment method as described in claim 1, characterized in that, wherein the substrate comprises insulating or non-insulating material.

44. The substrate surface treatment method as described in claim 1, characterized in that, wherein the substrate comprises metal or non-metal material.

45. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 45 wherein the substrate carries logic circuit, radio frequency circuit and / or memory circuit thereon.

46. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 46 wherein the substrate is bonded with another substrate by performing the planarization process step and the plasma treatment step.

47. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 47 wherein the substrate is bonded with another substrate by performing the planarization process step and the plasma treatment step.

48. The substrate surface treatment method of claim 47, wherein, wherein the substrate is bonded with another substrate by performing the hybrid bonding process to form a CoWoS structure, a CoPoS structure and / or a SoIC structure.

49. The method of claim 47, wherein the substrate surface is treated by a method comprising: wherein the substrate is bonded with another substrate by performing the planarization process step and the plasma treatment step to improve the yield of the hybrid bonding process.

50. The method of claim 1, wherein the substrate surface is a semiconductor wafer. 5 wherein the adjustable sequence is selected from a group consisting of sequential and reverse sequential.

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