Cleaned packaging substrate and method for manufacturing a cleaned packaging substrate

Abstract

A method for manufacturing a cleaned packaging substrate is provided. The method is applied to a manufacturing process of a glass substrate or a packaging substrate including the same. The method manufactures a cleaned packaging substrate by including: a preparation process of placing a target substrate in a chamber; and a removal process of spraying ionized air onto at least one surface of the target substrate to remove particulate foreign substances. The target substrate is a glass packaging substrate; or a packaging substrate, and the packaging substrate includes a redistribution layer disposed on at least one surface of the glass packaging substrate and the glass substrate for packaging.

Description

Technology Field

[0001] The following description relates to a method for manufacturing a cleaned packaging substrate and a cleaned packaging substrate.

[0002] Cross-reference for related applications

[0003] This application claims priority to U.S. Provisional Application No. 63 / 242,619 filed September 10, 2021, the entire disclosures of which are incorporated herein by reference for all purposes. Background Technology

[0004] In the manufacturing of electronic components, implementing circuits on a semiconductor wafer is called the front-end process (FE), and assembling the wafer into a state usable in an actual product is called the back-end process (BE). The packaging process is included in the back-end process.

[0005] Recently, the four core technologies of the semiconductor industry that have enabled the rapid development of electronic products are semiconductor technology, semiconductor packaging technology, manufacturing process technology, and software technology. Semiconductor technologies, such as sub-micron and nano-scale linewidths and more than ten million cells, can yield results in high-speed operation and heat dissipation, but they are not sufficiently supported by packaging technology. Consequently, the electrical performance of packaged semiconductors may be determined by packaging technology and electrical connections rather than by the performance of the semiconductor technology itself.

[0006] For example, a glass substrate can be applied as a high-end packaging substrate. By forming through-holes in the glass substrate and applying a conductive material to these through-holes, the wiring length between the device and the motherboard can be shortened, and excellent electrical characteristics can be obtained.

[0007] In order to form fine through holes in a glass substrate and connect redistribution layers, a strict cleaning process is essential. Foreign substances such as dust are particularly critical when fine lines are applied. Related prior art includes Korean Patent Publication No. 10-0528286 and Korean Patent Publication No. 10-0612407. The problem to be solved

[0008] The purpose of the embodiment is to provide a method for manufacturing a cleaned packaging substrate and a cleaned packaging substrate. means of solving the problem

[0009] This summary briefly introduces concepts that will be further explained below in the specific description. This summary is not intended to present the core or major features of the subject matter claimed as a right, nor is it intended to assist in determining the scope of the subject matter claimed as a right.

[0010] In one embodiment, a method for manufacturing a cleaned packaging substrate comprises positioning a target substrate in a chamber during a preparation process; spraying ionized air onto at least one surface of the target substrate to separate particulate impurities during a removal process, and obtaining a cleaned packaging substrate. The target substrate is at least one of a glass packaging substrate and a packaging substrate, and the packaging substrate comprises the glass packaging substrate and a redistribution layer disposed on at least one surface of the glass packaging substrate.

[0011] The above removal process may be configured to suppress the generation of static electricity caused by ionized air by irradiating soft X-rays onto the target substrate.

[0012] In the above removal process, the atmosphere of the chamber may have an airflow with a force applied in a direction opposite to gravity.

[0013] The ionized air sprayed in the above removal process may be one of an inert gas and dry air.

[0014] In the above removal process, the residual potential of the substrate may be 0 V.

[0015] In the above removal process, the space within the chamber can be maintained at a low-pressure atmosphere of 0.9 atmospheres or less.

[0016] In the above removal process, the injection of the ionized air may be performed on one side of the substrate and one side of the substrate, and the air may flow at an angle of 30 to 150 degrees relative to one side of the substrate.

[0017] The above glass package substrate may include a through-via penetrating in the thickness direction thereof, and the through-via may have an opening with a maximum length of 300 μm or less.

[0018] The redistribution layer of the packaging substrate may include blind vias. The blind vias may include openings with a maximum length of 20 μm or less.

[0019] Other features and aspects will become clear through the specific explanations provided below. Specific details for implementing the invention

[0020] The following detailed description is provided to aid in a full understanding of the methods, devices, and / or systems described herein. However, various variations, modifications, and equivalents of the methods, devices, and / or systems described herein will become clear upon understanding the disclosure of this application. For example, it will become clear upon understanding the disclosure of this application that the sequence of processes described herein is merely illustrative and is not limited to what is specified herein, and includes the exclusion of essential processes occurring in any sequence. Furthermore, it is noted that descriptions of features known upon understanding the disclosure of this application may be omitted to enhance clarity, and that the omission of features or descriptions thereof is not intended to acknowledge that they are general knowledge.

[0021] The features described herein may be modified in other forms and are not to be interpreted as being limited to the examples described herein. Furthermore, the examples described herein merely illustrate some of the various feasible methods of the method, apparatus, and / or system described herein, which will become apparent after understanding the disclosure of this application.

[0022] Terms such as “first,” “second,” or “third” are used to describe various configurations, elements, regions, layers, or parts, and these configurations, elements, regions, layers, or parts are not limited to these terms. Rather, these terms are used solely for the purpose of distinguishing one configuration, element, region, layer, or part from another configuration, element, region, layer, or part. Accordingly, the first configuration, element, region, layer, or part referenced in one embodiment is not excluded from those presented in the examples above and may also be referenced as a second configuration, element, region, layer, or part.

[0023] In this specification, when any configuration, such as a layer region or a substrate, is described as being "on," "connected," or "combined" with another configuration, this may mean that it is directly "on," "connected," or "combined," or that one or more other configurations are intervened between them. Conversely, when a configuration is described as being "directly on," "directly connected," or "directly combined" with another configuration, no other configurations may be intervened between them. Similarly, "between" and "immediately between," and "next to" and "immediately adjacent to" may be understood in a manner similar to that described above.

[0024] The terms described herein are presented for the purpose of describing individual embodiments, but are not limited thereto. As used herein, singular expressions include plural expressions unless otherwise noted. As used herein, the expression “and / or” includes any one or any combination of two or more associated items. As used herein, the terms “include” or “have” specify the presence of the mentioned feature, number, process, element, configuration and / or combination thereof, and do not exclude the addition or presence of other features, number, process, element, configuration and / or combination thereof. The use of the expression “may” with respect to an embodiment or configuration (e.g., in relation to that an example or configuration may include or be configured) means that at least one example or configuration includes or is configured with a certain feature, and that not all embodiments are limited thereto.

[0025] Unless otherwise defined, all terms, including technical and scientific terms, are used in the same sense as generally understood by a person of ordinary knowledge in this technical field after understanding the contents disclosed herein, while maintaining consistency.

[0026] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology and the present invention, and should not be interpreted in an idealized or overly formal sense unless explicitly defined in this specification.

[0027] In this application, the description "A and / or B" means "A, B, or A and B".

[0028] In this application, terms such as "first," "second," "A," or "B" are used to distinguish the same terms from one another, unless otherwise specifically noted.

[0029] One or more embodiments provide a clean packaging-based manufacturing method and a clean packaging substrate.

[0030] In one or more embodiments, the cleaned packaging-based manufacturing method and the cleaned packaging substrate can minimize damage to the substrate that may occur due to the influence of static electricity during the cleaning process and can effectively remove foreign substances from the substrate having complex structures or small holes.

[0031] In one or more embodiments, the singular form is contextually interpreted to include not only the singular form but also the plural form unless specifically noted otherwise.

[0032] Packaging substrates for packaging high-performance devices require controlling the difference in wiring scale between the board at the bottom of the substrate and the device at the top. To achieve this, methods such as applying two or more layers of pre-legs or applying a two-layer combination of pre-legs and silicon substrates have been adopted. This is because the difference in wiring scale between the board placed at the bottom of the packaging substrate and the device placed at the top can be controlled relatively easily through the use of a two-layer substrate. However, this approach is difficult to satisfy the requirements of thin-film semiconductor device packaging.

[0033] For packaging substrates of high-performance semiconductor devices, a single-layer glass substrate can be used as a support layer. In this case, it is necessary to arrange lines or vias of various sizes within a single packaging substrate. In order for a finely rewired layer to be applied, for via sizes to be reduced, and for complex wiring patterns to be implemented within a small area of ​​the packaging substrate, precise control of foreign substances is required. Therefore, the importance of the cleaning process in the manufacturing process of the packaging substrate is also increasing.

[0034] Glass substrates can be used as the core of packaging substrates. By using stress-controlled glass substrates for semiconductor packaging, it is possible to implement fine lines with a thinner thickness. However, glass substrates are vulnerable to impact or stress imbalance. Therefore, if an energy imbalance occurs within the glass substrate, the substrate itself may break, which can lead to the inconvenience of having to clean the entire process chamber.

[0035] Therefore, it is necessary to apply a cleaning method that efficiently removes foreign substances while minimizing stress imbalances and impacts on glass substrates or packaging substrates using them as cores.

[0036] The following describes an example of implementation in more detail.

[0037] A method for manufacturing a cleaned packaging substrate is applied to a manufacturing process of a glass substrate or a packaging substrate including the same, and includes a preparation process and a removal process.

[0038] The above preparation process is a process of placing the target substrate inside the chamber.

[0039] The arrangement of the above-mentioned target substrate means placing the target substrate at a predetermined location and, although not limited thereto, fixing it so that it does not detach due to interaction with elements such as air injection.

[0040] The above fixing process may involve placing the target substrate on a shelf provided within the chamber. The above fixing process may involve placing the target substrate on a multi-stage shelf provided within the chamber.

[0041] The above removal process is a process for manufacturing a cleaned substrate for packaging by spraying ionized air onto at least one surface of the target substrate and detaching particulate foreign substances.

[0042] The above-mentioned target substrate is a glass substrate for packaging; or a substrate for packaging.

[0043] The above glass packaging substrate may be a glass substrate for semiconductors, and, for example, may be a borosilicate glass substrate, an alkali-free glass substrate, etc.

[0044] The glass packaging substrate may include a through-via penetrating in the thickness direction thereof. The through-via may include an opening having a maximum length of about 300 μm or less. The through-via may have an aspect ratio of about 0.5 to about 1.5, and the aspect ratio is the ratio of the maximum length of the opening to the height of the through-via (corresponding to the thickness of the glass substrate).

[0045] If the opening of the above-mentioned through-via is narrow or the aspect ratio is large, a more meticulous removal process must be applied to ensure sufficient cleaning of the inside of the via.

[0046] The above glass substrate may include a cavity that is partially or entirely recessed in the thickness direction.

[0047] The above removal process can sufficiently remove foreign matter not only from the surface of the glass substrate, but also from the inside of the via, the sides and bottom of the cavity, etc.

[0048] The above packaging substrate includes a redistribution layer disposed on at least one surface of the glass packaging substrate and the glass substrate for packaging.

[0049] The above redistribution layer can be disposed on one side of the glass packaging substrate.

[0050] The above redistribution layer can be disposed on one side and the other side of the above-mentioned glass substrate for packaging, respectively.

[0051] The redistribution layer of the above-mentioned packaging substrate may include blind vias.

[0052] The above blind via may include an opening with a maximum length of about 20 μm or less, and may include an opening with a maximum length of about 12 μm or less.

[0053] A redistribution layer disposed on one side of the glass packaging substrate may be connected to the other side of the glass packaging substrate through a core which is a glass substrate. The other side may be connected to an external element through a buff or a similar device. The other side may be connected to an external element through a redistribution line, a buff, or a similar device disposed on the other side.

[0054] The above redistribution layer may include an electrically conductive layer that is a fine wire. The term "fine wire" refers to an electrically conductive layer with a width of less than about 4 μm. Specifically, the electrically conductive layer may be applied with a width and spacing of less than about 4 μm each, and may be about 1 μm to about 4 μm.

[0055] The thickness of the above-mentioned target substrate may be about 1,500 μm or less, about 300 μm to about 1,200 μm, 350 μm to 900 μm, or 350 μm to 700 μm.

[0056] The formation of the redistribution layer proceeds through a multi-step operation in which the formation of an insulating layer, the formation of vias, plating, and etching are repeated. At each step, cleaning processes are required, such as the formation of vias, the formation of an insulating layer, subsequent planarization, and the removal of unnecessary foreign substances after plating and etching.

[0057] During this process, if the process proceeds with foreign substances, such as dust, incorporated into even a part of the substrate, it can cause defects such as bridge defects, open defects, and edge defects. To prevent this, it is necessary to sufficiently remove foreign substances regardless of the complex morphology of the substrate surface or differences in the substrate surface material.

[0058] In particular, the packaging glass substrate is a material with insulating properties, which may result in damage such as broken or shattered glass. Therefore, cleaning may be required even inside the chamber. Furthermore, damage may occur to the glass substrate itself. Moreover, if an imbalance of electric charge within a single glass substrate exceeds a certain level, the glass substrate itself may break. Therefore, it is necessary to manage not only impact during the manufacturing process but also ions and static electricity during the cleaning process.

[0059] The above removal process removes particulate foreign substances by spraying the ionized air onto the target substrate.

[0060] The above air injection can be carried out through a nozzle.

[0061] The air sprayed above may be applied in a manner that sprays ionized air, or it may be treated to become ionized on the substrate surface after spraying the air.

[0062] The air sprayed above may be an inert gas or dry air.

[0063] The above-mentioned inert gas may include nitrogen gas, argon gas, etc., but is not limited thereto.

[0064] In the above removal process, the air injection may be performed on one side of the substrate or on the other side of the substrate.

[0065] The air may be introduced at an angle of approximately 30 to approximately 150 degrees relative to one surface of the substrate. It may be introduced at an angle of approximately 30 to approximately 85 degrees, or at an angle of approximately 95 to approximately 150 degrees. The angle of air introduction can be determined through the angle of the nozzle.

[0066] For the removal of foreign substances from the substrate surface, it is important to detach them using air. In addition, it is also important to control the process to prevent the detached substances from adhering to the substrate surface again.

[0067] The occurrence of static electricity or charge imbalance can occur on the surface of the target substrate due to air jets. This tends to be more severe when the target substrate is an insulator.

[0068] By applying a method of air flow control and / or ultraviolet irradiation within the chamber along with the injection of ionized air, the generation of static electricity can be suppressed, and efficient removal of foreign matter can be achieved without substantially damaging the substrate.

[0069] Controlling the airflow within the chamber means forming an airflow to which a force opposite to gravity is applied. Ideally, partial turbulence may be formed. When turbulence is applied to the airflow within the chamber, foreign substances displaced by the injected air can move along the turbulence within the chamber and be efficiently removed, while preventing re-adherence to the substrate.

[0070] In the above removal process, the space within the chamber can be maintained at a low-pressure atmosphere of 0.9 atmospheres or less.

[0071] The above removal process can be carried out by irradiating the target substrate with soft X-rays while suppressing the generation of static electricity.

[0072] There are various ways to suppress static electricity.

[0073] Methods such as soft X-rays, electromagnetic ionizers, ultraviolet lamps, and atmospheric pressure plasma can be used. In one or more examples, the soft X-ray method can be applied.

[0074] Electrostatic suppression using soft X-rays can form ions or electrons through the ionization of air molecules near the target substrate, thereby controlling static electricity on the surface of the target substrate. Since a light irradiation method can be applied, it has the advantage of not requiring a separate device for ion delivery, unlike the plasma method. Furthermore, it is more advantageous than using UV lamps because it does not generate substantial amounts of ozone even when irradiated in an oxygen-containing atmosphere.

[0075] Soft X-rays can be applied with light having a wavelength of about 1 Angstrom to about 700 Angstroms, or with light having a wavelength of about 1 Angstrom to about 10 Angstroms. Additionally, the ionization energy can be applied at about 10 keV or less, or at about 1 keV to about 10 keV. Soft X-rays can be irradiated at a distance of about 50 cm or less from the target substrate, or at a distance of about 2 cm to about 30 cm. In this case, static electricity can be controlled more effectively.

[0076] The above removal process can reduce the residual potential to substantially 0 V. In this case, the re-adsorption of foreign substances by static electricity is suppressed, and damage to the substrate caused by ionization or static electricity can be reliably prevented.

[0077] The above-described method for manufacturing a cleaned packaging substrate can reliably remove foreign substances from a target substrate without substantially causing damage or deformation to the substrate itself. Furthermore, it can be stably and efficiently applied to high-insulation materials such as glass substrates.

[0078] In another embodiment, a method for manufacturing a packaging substrate may include a glass substrate preparation step; a substrate electrically conductive layer formation step; an insulating layer formation step; a conductive layer formation step; a cleaning step; and an inspection step.

[0079] The preparation step for preparing a glass substrate is a step of preparing a glass substrate for semiconductor packaging. This glass substrate is in the form of a thin plate and may include cavities and / or vias as needed. A cavity refers to a recessed portion of the glass substrate, and the recessed portion may penetrate the glass substrate or remain partially intact without penetrating it.

[0080] In the glass substrate preparation step, a glass substrate must be prepared that has been cleaned or had static electricity removed. Additional cleaning or static electricity removal processes may be performed before proceeding to the next step.

[0081] Here, the cleaning step may utilize the removal process described above, and for electrostatic removal, the step utilizing soft X-rays mentioned above may be applied as an example; these steps may be applied simultaneously or sequentially.

[0082] The step of forming an electrically conductive layer on a substrate is the step of forming an electrically conductive layer of a predetermined pattern on the surface of the glass substrate.

[0083] The glass substrate may have vias or cavities, and an electrically conductive layer may be formed inside the vias and on the walls of the cavities according to a predetermined method.

[0084] The formation of the above electrically conductive layer may be carried out, for example, by forming a copper or copper alloy layer through plating, sputtering, etc. For example, a primer layer may be formed at a predetermined location, and after forming an insulating layer, etc., a portion of the area where the electrically conductive layer is to be formed may be removed, and copper plating may be performed to form an electrically conductive layer of the intended shape and thickness. If necessary, the copper plating layer may be flattened.

[0085] The insulating layer formation step involves incorporating an insulating layer between electrically conductive layers, which can be carried out by curing a polymer resin containing nanoparticles. It is preferable that the surface (upper surface) of the insulating layer be flattened.

[0086] The step of forming a conductive layer is the step of forming an electrically conductive layer at a required location on the insulating layer. The formation of the electrically conductive layer may, for example, proceed by forming a copper or copper alloy layer through plating, sputtering, etc. For example, a primer layer may be formed at a predetermined location, and after forming an insulating layer, etc., a portion of the area where the electrically conductive layer is to be formed may be removed, and copper plating may be performed to form an electrically conductive layer of the intended shape and thickness. If necessary, the copper plating layer may be flattened.

[0087] The cleaning step is the cleaning step mentioned above, and the removal of dust and / or static electricity through airflow may be applied.

[0088] The inspection stage is a step to verify whether there are any defects in the substrate or wires, and whether any foreign substances that may have occurred during the manufacturing process have been properly removed. This can be conducted using specialized inspection equipment, and packaging substrates that fail the inspection may undergo a re-cleaning stage or be discarded.

[0089] Between the insulating layer formation step and the conductive layer formation step, a via formation step and a cleaning step may optionally be further included.

[0090] Between the step of forming an insulating layer and the step of forming a conductive layer, a via formation step, a via conductive layer formation step, and a cleaning step may optionally be further included.

[0091] Between the step of forming an insulating layer and the step of forming a conductive layer, a via formation step, a cleaning step, a via conductive layer formation step, and a cleaning step may optionally be further included.

[0092] The via formation step forms vias for purposes such as connecting vertically arranged conductive layers. For example, the vias may be formed by etching a portion of the insulating layer at a predetermined location and size. For example, laser etching, plasma etching, etc., may be applied as the etching. After the etching, a step of optionally removing etching residue or checking whether it has been removed may be further included.

[0093] The via conductive layer formation step is a step of forming a conductive layer in the via. The conductive layer may be formed with a relatively uniform thickness along the inner diameter surface of the via. The conductive layer may be formed to completely fill the via. Since the formation of the conductive layer is similar to the process of forming the electrically conductive layer mentioned above, the description thereof is omitted.

[0094] The insulating layer formation step and the conductive layer formation step may be repeated several times as needed. Additionally, steps added between the insulating layer formation step and the conductive layer formation step may also be repeated several times as needed.

[0095] The descriptions for each step are omitted as they overlap with the description above.

[0096] For example, the glass substrate may be a glass substrate having a cavity structure.

[0097] At this time, between the step of forming an electrically conductive layer on the substrate and the step of forming an insulating layer, a step of placing an element (referred to as a cavity element in the sense that it is a element placed inside the cavity) may be further included.

[0098] The above cavity element may use capacitors such as MLCCs, but is not limited thereto.

[0099] The step of placing an element in a cavity, etc., may include placing a cavity element at a predetermined location and forming an insulating layer, a conductive layer, an insulating layer, etc. at a predetermined location.

[0100] A solder ball attachment step may be further included before or after the above inspection step.

[0101] The solder ball attachment step is a step of attaching solder balls disposed on the upper surface and / or lower surface of the substrate.

[0102] Solder balls directly connect the packaging substrate to external components and can be processed through the following steps.

[0103] The process of providing a pad at a location where a solder ball is to be formed, the process of opening the upper surface of the pad to form an insulating film on one side of the substrate, the process of providing a metal masking layer on the upper surface of the pad, and the process of positioning a buff and a metal ball can be applied sequentially.

[0104] The pad may be made of aluminum as an example, but is not limited thereto. The metal masking layer may be formed with one or more layers of copper alloy, titanium, etc., as an example, but is not limited thereto. The metal ball may be made of tin ball as an example, but is not limited thereto.

[0105] The method for manufacturing packaging substrates can reliably remove foreign substances from a target substrate without substantially causing damage or deformation to the substrate itself. Furthermore, it can be stably and efficiently applied even to high-insulation materials such as glass substrates.

[0106] A packaging substrate according to another embodiment is cleaned in the manner described above. The cleaned packaging substrate can efficiently suppress bridge defects, open defects, etch defects, etc., and provide a packaging substrate with improved reliability.

[0107] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it is obvious that various modifications and improvements by those skilled in the art using the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention. The examples described herein should be considered for illustrative purposes only and should not be considered for the purpose of limiting rights. Descriptions of features or aspects in each example are considered applicable to similar features or aspects in other examples. If the described techniques are performed in a different order, and / or if the components of the described system, configuration, device, or circuit are combined in a different way, and / or are replaced or supplemented by other components or equivalents, appropriate results may be achieved.

[0108] Therefore, the scope of disclosure is defined not by the detailed description but by the claims and their equivalents, and all variations and equivalents within the claims are interpreted as being included in the disclosure.

Claims

Claim 1 In the preparation process, a target substrate is positioned within a chamber; in the removal process, ionized air is sprayed onto at least one surface of the target substrate to separate particulate impurities, and a cleaned packaging substrate is obtained; the target substrate is at least one of a glass packaging substrate and a packaging substrate; the packaging substrate includes the glass packaging substrate and a redistribution layer disposed on at least one surface of the glass packaging substrate; in the removal process, soft X-rays are irradiated onto the target substrate to suppress the generation of static electricity caused by ionized air; the soft X-rays are light with a wavelength of 1 Angstrom to 700 Angstroms and an ionization energy of 1 keV to 10 keV, and are irradiated at a distance of within 50 cm from the target substrate; in the removal process, the residual counterpotential of the substrate is 0 V; the ionized air sprayed in the removal process is one of an inert gas and dry air; and in the removal process, the space within the chamber is in a low-pressure atmosphere of 0.9 atmospheres or less. A method for manufacturing a cleaned packaging substrate, wherein the glass packaging substrate is maintained, the glass packaging substrate includes a through-via penetrating in the thickness direction thereof, the through-via has an opening with a maximum length of 300 μm or less, the redistribution layer of the packaging substrate includes a blind via, and the blind via has an opening with a maximum length of 20 μm or less. Claim 2 delete Claim 3 In claim 1, the atmosphere of the chamber in the removal process has an airflow to which a force opposite to gravity is applied. Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A method according to claim 1, wherein in the removal process, the injection of the ionized air is performed on one side of the substrate and one side of the substrate, and the air is introduced at an angle of 30 to 150 degrees relative to one side of the substrate. Claim 8 delete Claim 9 delete Claim 10 delete