Patent Application
20240105652
The present application claims priority under 35 U.S.C. § 119(a) to Korean application number 10-2022-0122851, filed in the Korean Intellectual Property Office on Sep. 27, 2022, the entire disclosure of which is incorporated herein by reference.
The present disclosure relates to a semiconductor technology and, particularly, to a method of manufacturing a semiconductor device including a conductive bump.
As the performance, degree of integration, and speed of semiconductor devices are increased and the sizes of semiconductor devices are reduced, the number of input/output (I/O) terminals for interconnections that are necessary for the semiconductor devices is increased. As high-speed operation and power reduction are required for the semiconductor devices, it becomes necessary to reduce paths for the interconnections. Accordingly, conductive bumps are increasingly adopted for the semiconductor devices as elements for the interconnections. Furthermore, it is necessary to develop a technology in which a larger number of bumps are applied to semiconductor devices.
To apply a larger number of bumps to a semiconductor substrate or semiconductor the that constitutes a semiconductor device, it is necessary to reduce a critical dimension size of bumps. As the critical dimension size of the bumps is reduced, it becomes difficult to maintain bonding integrity between the bumps and the semiconductor die. Accordingly, attempts to improve the bonding strength between the bumps and the semiconductor die by changing shapes of the bumps are being made.
A method of manufacturing a semiconductor device in accordance with the present disclosure includes: forming a first photoresist layer on a substrate; forming a second photoresist layer on the first photoresist layer; forming a first dissolvable region having a first width in the first photoresist layer and a second dissolvable region having a second width different from the first width in the second photoresist layer by radiating exposure light to some parts of the second and first photoresist layers; forming a second opening in the second photoresist layer and a first opening in the first photoresist layer by developing the second dissolvable region and the first dissolvable region; and forming a conductive bump that fills the first and second openings.
A method of manufacturing a semiconductor device in accordance with the present disclosure includes: forming a first photoresist layer on a substrate; forming, on the first photoresist layer, a second photoresist layer in which a second diffusion distance at which a second add, that is generated by exposure light incident on a part of the second photoresist layer, is diffused is different from a first diffusion distance at which a first acid, that is generated by the exposure light incident on a part of the first photoresist layer, is diffused in the first photoresist layer; forming, as a result of the incident exposure light, a first dissolvable region having a first width in the first photoresist layer and a second dissolvable region having a second width different from the first width in the second photoresist layer; forming a second opening in the second photoresist layer and a first opening in the first photoresist layer by developing the second dissolvable region and the first dissolvable region; and forming a conductive bump that fills the first and second openings.
Terms that are used in the description of examples of this application are terms selected by taking into consideration functions in proposed embodiments, and the meanings of the terms may be different depending on a user, an operator's intention or practice in the technical field. The meaning of a term used follows the definition of the term if the term has been specifically defined in this specification, and may be interpreted as a meaning which may be commonly recognized by those skilled in the art if the term has not been specifically defined.
In the description of examples of this application, terms, such as a “first”, a “second”, a “side”, a “top”, and a “bottom or lower”, are used to distinguish between members and are not used to limit the members themselves or to mean a specific order.
A semiconductor substrate may denote a semiconductor wafer on which electronic parts and elements are integrated. Integrated circuits may be integrated on the semiconductor substrate. The semiconductor substrate may be diced into a plurality of semiconductor chips or a plurality of semiconductor dies.
A semiconductor chip may be a memory chip on which memory devices, such as DRAM, SRAM, NAND flash memory, NOR flash memory, MRAM, ReRAM, FeRAM, or PcRAM, have been integrated. A semiconductor chip may denote a logic die or an ASIC chip, an application processor (AP), a graphic processing unit (GPU), a central processing unit (CPU), or a system on chip (SoC) in which logic circuits have been integrated on a semiconductor substrate.
A semiconductor chip may be a component that constitutes a semiconductor package or a semiconductor product. Semiconductor chips may be applied to information communication devices such as a mobile terminal, bio or health care-related electronic devices, and electronic devices wearable by human beings. A semiconductor chip may be applied to Internet of Things.
In the entire specification, the same reference numerals may denote the same components. Accordingly, the same reference numerals or similar reference numerals may be described with reference to other drawings although they are not mentioned or described in corresponding drawings. Furthermore, although reference numerals are not shown, they may be described with reference to other drawings.
Referring to
A third photoresist layer 400 may be further formed on the second photoresist layer 300. The third photoresist layer 400 may be formed to include a photoresist substance that is different from that of the second photoresist layer 300. Alternatively, the third photoresist layer 400 may be formed to include a photoresist substance that is different from that of the first photoresist layer 200. The photoresist layers 200, 300, and 400 may include a plurality of two or more layers. The structure in which the photoresist layers 200, 300, and 400 have been stacked as described above may be used as an element that provides a mold to form a conductive bump.
The substrate 100 may be a device substrate in which memory devices, semiconductor devices, or integrated circuits have been integrated. The memory devices may be volatile memory devices such as those using dynamic random access memory (DRAM). The memory devices may be nonvolatile memory devices such as those using NAND flash memory. The substrate 100 may be a semiconductor substrate including a semiconductor substance. The semiconductor substrate may be a substrate including silicon (Si) or germanium (Ge) or may be a substrate including silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphorous (InP). The substrate 100 may denote a semiconductor die. The substrate 100 may be an element on which semiconductor dies are mounted like a printed circuit board.
The substrate 100 may further include a conductive pad 110. The conductive pad 110 may be a bump land to which a conductive bump is to be connected. The conductive pad 110 may be some part of a wire that is electrically connected to an integrated circuit that is integrated within the substrate 100. The conductive pad 110 may be formed to include a metal substance, such as aluminum (Al).
A plating seed layer 150 may be further formed between the substrate 100 and the photoresist layers 200, 300, and 400. The plating seed layer 150 may be formed between the first photoresist layer 200 and the substrate 100. The plating seed layer 150 may be formed as a conductive layer for a process of plating a conductive bump. The plating seed layer 150 may include a metal substance, such as copper (Cu), nickel (Ni), or gold (Au). The plating seed layer 150 may include an under bump metal layer.
Referring to
The quencher may include an alkaline compound that is added to the photoresist to control or adjust the behavior of the acids that are generated from the PAG due to the reaction of the PAG to exposure light. The polymer may be a polymer having a carbon chain. The protection functionality may include polyhydroxystyrene. The PAG may be a compound that generates acids, such as hydrogen ions (H+), by exposure light. The generated acids may substitute the protection functionality with hydroxyl groups through a reaction of deprotecting the protection functionality. The substituted hydroxyl group has relatively high solubility with respect to a developer, that is, a weak alkali solution, so that a pattern of the photoresist layer may be formed in the form of an exposed pattern through a developing process.
Such a photoresist may be a photoresist for a KrF light source, a photoresist for an ArF light source, or a chemical amplification photoresist. The photoresist layer 200, 300, or 400 may be formed by coating, on the substrate 100, a photoresist solution in which the photoresist has been dissolved in a solvent and performing a soft bake that removes a certain part of the solvent.
The first photoresist layer 200 may be formed to include a first photoresist. The first photoresist may include a first polymer and a first protection functionality that is combined with the first polymer, and may include a first PAG and a first quencher. A first photoresist layer 200 may be formed by coating, on the substrate 100, a first photoresist solution in which the first photoresist has been dissolved in a first solvent and performing a soft bake. A second photoresist layer 300 may be formed by coating, on the first photoresist layer 200, a second photoresist solution in which a second photoresist has been dissolved in a second solvent and performing a soft bake. The second photoresist may include a second polymer and a second protection functionality that is combined with the second polymer, and may include a second PAG and a second quencher.
As described above, the first and second photoresist layers 200 and 300 may be formed by using the first and second photoresists that are different from each other. The second polymer may be the type of polymer that is different from the type of first polymer. The second polymer may be a polymer having a molecular weight that is different from that of the first polymer. The second protection functionality may be a protection functionality that is different from that of the first protection functionality. The number of second protection functionalities that have been combined with the second polymer may be different from the number of first protection functionalities that have been combined with the first polymer. The second PAG may be a PAG having an acid production rate that is different from that of the first PAG. The second quencher may be added to the second photoresist or the second photoresist layer 300 with a content that is different from the content of the first quencher added to the first photoresist or the first photoresist layer 200. The first and second photoresist layers 200 and 300 may be exposed and developed in the form of patterns having different forms.
Referring to
Referring to
In
The some parts of the photoresist layers 200, 300, and 400 may be exposure regions 201, 301, and 401 on which the exposure light 600 is incident. The exposure light 600 that is radiated to the stack structure of the photoresist layers 200, 300, and 400 may be incident on the third exposure region 401 of the third photoresist layer 400, may be incident on the second exposure region 301 of the second photoresist layer 300 under the third exposure region 401 while passing through the third exposure region 401, may be incident on the first exposure region 201 of the first photoresist layer 200 under the second exposure region 301 while passing through the second exposure region 301, and may be radiated to the first exposure region 201. Because the exposure light 600 is radiated to the stack structure of the photoresist layers 200, 300, and 400, some parts of the photoresist layers 200, 300, and 400 or the exposure regions 201, 301, and 401 of the photoresist layers 200, 300, and 400 may be exposed at once. The exposure regions 201, 301, and 401 may be regions that are overlapped perpendicularly to each other because the exposure regions 201, 301, and 401 of the photoresist layers 200, 300, and 400 are radiated by a single exposure of exposure light 600. The exposure regions 201, 301, and 401 may be regions that have substantially the same width.
Referring to
Referring to
By making different the type of photoresists that constitute the photoresist layers 200, 300, and 400, respectively, a first diffusion distance D1 at which the first add 701 is diffused within the first photoresist layer 200 may be different from a second diffusion distance D2 at which the second acid 702 is diffused within the second photoresist layer 300. Accordingly, the first diffusion region 201D that is formed within the first photoresist layer 200 may have a width different from that of the second diffusion region 301D that is formed within the second photoresist layer 300. A third diffusion distance D3 at which the third acid 703 is diffused within the third photoresist layer 400 may be different from the second diffusion distance D2 or the first diffusion distance D1. A third diffusion region 401D that is formed within the third photoresist layer 400 may have a width different from that of the second diffusion region 301D or the first diffusion region 201D.
By making different the type of photoresists that constitute the photoresist layers 200, 300, and 400, respectively, the first diffusion distance D1 at which the first acid 701 is diffused within the first photoresist layer 200 may be longer than the second diffusion distance D2 at which the second acid 702 is diffused within the second photoresist layer 300. Accordingly, the first diffusion region 201D that is formed within the first photoresist layer 200 may have a greater width than the second diffusion region 301D that is formed within the second photoresist layer 300. The third diffusion distance D3 at which the third acid 703 is diffused within the third photoresist layer 400 may be shorter than the second diffusion distance D2 or the first diffusion distance D1. The third diffusion region 401D that is formed within the third photoresist layer 400 may have a smaller width than the second diffusion region 301D or the first diffusion region 201D.
The diffusion distances D1, D2, and D3 at which the acids 701, 702, and 703 are diffused into the photoresist layers 200, 300, and 400 may be different from each other by the influence of components or compositions of the photoresists. The diffusion distances D1, D2, and D3 of the acids may be different depending on type or content of a PAG that is included in a photoresist or an acid production rate, that is, the degree that acids are generated by a PAG. The diffusion distances D1, D2, and D3 of the acids may be different depending on the type or molecular weight of a polymer that constitutes a photoresist, the type of protection functionalities, or the number of protection functionalities that have been combined with a polymer. The diffusion distances D1, D2, and D3 of the acids may be different depending on the type or content of a quencher that is contained in a photoresist.
If the first diffusion region 201D is to be formed wider than the second diffusion region 301D by making longer the first diffusion distance D1 of the first acids 701 in the first photoresist layer 200 than the second diffusion distance D2 of the second acids 702 in the second photoresist layer 300, the first photoresist layer 200 may be formed of the first photoresist that includes the first polymer having a lower molecular weight than the second polymer included in the second photoresist that constitutes the second photoresist layer 300. Alternatively, the first photoresist layer 200 may be formed of the first photoresist that includes the first PAG having a higher acid production rate than the second PAG that is included in the second photoresist. Alternatively, the first photoresist may be formed so that the number of first protection functionalities that are combined with the first polymer is smaller than the number of second protection functionalities that are combined with the second polymer. Alternatively, the first photoresist may be formed so that the first quencher is included with a higher content than the content of the second quencher of the second photoresist.
Referring to
The dissolvable regions 201S, 301S, and 401S may have different widths because the diffusion regions 201D, 301D, and 401D of the photoresist layers 200, 300, and 400 have different widths. The first dissolvable region 201S having a first width W1 may be formed in the first photoresist layer 200. The second dissolvable region 301S having a second width W2 may be formed in the second photoresist layer 300. The second width W2 of the second dissolvable region 301S may be different from the first width W1. The third dissolvable region 401S having a third width W3 may be formed in the third photoresist layer 400. Accordingly, the second width W2 may be smaller than the first width W1, and the third width W3 may be smaller than the second width W2.
Because the dissolvable regions 201S, 301S, and 401S are formed by the deprotection reactions of the acids 701, 702, and 703 and the protection functionalities, the dissolvable regions 201S, 301S, and 401S may have substantially the same widths as the diffusion regions 201D, 301D, and 401D of the photoresist layers 200, 300, and 400 in which the adds 701, 702, and 703 have been distributed, respectively,
Referring to
As the third dissolvable region 401S is developed from the third photoresist layer 400 by the developer, the third opening 401H may be formed in the third photoresist layer 400. As the second dissolvable region 301S is developed from the second photoresist layer 300 by the developer that is introduced through the third opening 401H, the second opening 301H may be formed in the second photoresist layer 300. As the first dissolvable region 201S is developed from the first photoresist layer 200 by the developer that is introduced through the third and second openings 401H and 301H, the first opening 201H may be formed in the first photoresist layer 200.
The first opening 201H may have a fourth width H1 according to the first width W1 of the first dissolvable region 201S. The fourth width H1 of the first opening 201H may have substantially the same size as the first width W1. The second opening 301H may have a fifth width H2 according to the second width W2 of the second dissolvable region 301S. The third opening 401H may have a sixth width H3 according to the third width W3 of the third dissolvable region 401S. Because the dissolvable regions 201S, 301S, and 401S may have different widths W1, W2, and W3, the openings 201H, 301H, and 401H may have the widths H1, H2, and H3 having different sizes according to the widths W1, W2, and W3 of the dissolvable regions 201S, 301S, and 401S, respectively. Accordingly, a shape in which the openings 201H, 301H, and 401H overlap may have a side profile having a staggered or stair shape. The shape in which the openings 201H, 301H, and 401H overlap may have a hole shape the widths of which are different in a direction that becomes distant from the substrate 100. The shape in which the openings 201H, 301H, and 401H overlap may have a hole shape the widths of which are reduced as the widths become distant from the substrate 100.
Referring to
The conductive bump 801 may be formed to include metal, such as copper (Cu). The conductive bump 801 may be formed by a plating process. The conductive bump 801 may be plated in some part 150R of the plating seed layer 150, which is exposed to the first and second openings 201H and 301H. The plating process may be performed so that the conductive bump 801 is further extended by filling the third opening 401H.
Referring to
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Referring to
Referring to
By exposing and developing the stack structure of the photoresist layers 400-1, 300-1, and 200-1, a third opening 401H-1 may be formed in the third photoresist layer 400-1, a second opening 301H-1 may be formed in the second photoresist layer 300-1, and a first opening 201H-1 may be formed in the first photoresist layer 200-1. The third, second, and first openings 401H-1, 301H-1, and 201H-1 may be formed to have different widths. The third, second, and first openings 401H-1, 301H-1, and 201H-1 may be formed to have widths that are sequentially relatively reduced.
The conductive bump 801-1 that fills the third and second openings 401H-1 and 301H-1 may be formed. The solder layer 802-1 that fills the first opening 201H-1 may be formed on the conductive bump 801-1. The conductive bump 801-1 may include a bottom part having an eleventh width B3-1 and a top part having a twelfth width 132-1. The eleventh width B3-1 of the bottom part of the conductive bump 801-1 may be smaller than the twelfth width 132-1 of the top part of the conductive bump 801-1.
As described above, the side profile of the conductive bump 801-1 may have a staggered or stair shape having various forms by changing the stack sequence or forming sequence of the photoresist layers 400-1, 300-1, and 200-1 that are stacked on the substrate 100.
Referring to
As presented in
As presented in
Referring to
The third photoresist layer 400 in which the third diffusion distance D3 at which the third acid 703 that is generated by the exposure light 600 is diffused is different from the first diffusion distance D1 or the second diffusion distance D2 may be formed on the second photoresist layer 300. The third dissolvable region 401S may be formed in the third photoresist layer 400 while forming the first and second dissolvable regions 201S and 301S as presented in
The memory device 7810 may be a nonvolatile memory device to which the technology of the embodiments of the present disclosure is applied. The memory controller 7820 may control the memory device 7810 such that stored data is read out or data is stored in response to a read/write request from a host 7830.
In an embodiment, the controller 8711 may include one or more microprocessor, digital signal processor, microcontroller, and/or logic device capable of performing the same functions as these components. The controller 8711 or the memory device 8713 may include at least one of the semiconductor packages according to the embodiments of the present disclosure. The input/output device 8712 may include at least one selected among a keypad, a keyboard, a display device, a touchscreen and so forth. The memory device 8713 is a device for storing data. The memory device 8713 may store data and/or commands to be executed by the controller 8711, and the like.
The memory device 8713 may include volatile memory such as DRAM and/or nonvolatile memory such as flash memory. For example, flash memory may be mounted to an information processing system such as a mobile terminal or a desktop computer. The flash memory may constitute a solid state disk (SSD). In this case, the electronic system 8710 may stably store a large amount of data in a flash memory system.
The electronic system 8710 may further include an interface 8714 configured to transmit and receive data to and from a communication network. The interface 8714 may be a wired or wireless type. For example, the interface 8714 may include an antenna or a wired or wireless transceiver.
The electronic system 8710 may be realized as a mobile system, a personal computer, an industrial computer, or a logic system performing various functions. For example, the mobile system may be any one of a personal digital assistant (PDA), a portable computer, a tablet computer, a mobile phone, a smart phone, a wireless phone, a laptop computer, a memory card, a digital music system, and an information transmission/reception system.
If the electronic system 8710 is an equipment capable of performing wireless communication, the electronic system 8710 may be used in a communication system using a technique of CDMA (code division multiple access), GSM (global system for mobile communications), NADC (north American digital cellular), E-TDMA (enhanced-time division multiple access), WCDMA (wideband code division multiple access), CDMA2000, LTE (long term evolution), or Wibro (wireless broadband Internet).
Only a limited number of possible embodiments for the present disclosure have been described above. A person having ordinary knowledge in the art to which the present disclosure pertains will understand that the present teachings may be implemented in a modified form without departing from an intrinsic characteristic of the present disclosure. Accordingly, the disclosed embodiments should be considered from a descriptive viewpoint, not from a limitative viewpoint. The range of the present disclosure is described in the claims not the aforementioned description, and all differences within an equivalent range thereof should be construed as being included in the present disclosure,
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0122851 | Sep 2022 | KR | national |
