Method for activating high-concentration semiconductor film and method foe manufacturing 3D memory using the same

Abstract

A method for activating a high-concentration semiconductor film and a method for manufacturing a three-dimensional memory using the same are disclosed. A method for activating a high-concentration semiconductor film according to embodiments may include: a step of preparing a semiconductor structure comprising a high-concentration semiconductor film exposed in a first direction; a step of forming a thermal conductive film so as to be in contact with the high-concentration semiconductor film exposed in the first direction and simultaneously in contact with a surface corresponding to a second direction in which a laser is irradiated from the semiconductor structure; and a step of activating the high-concentration semiconductor film by transferring heat through the thermal conductive film to the high-concentration semiconductor film in response to laser annealing being performed by irradiating the laser in the second direction.

Description

Technology Field

[0001] The following embodiments relate to a high-concentration semiconductor film activation method and a three-dimensional memory manufacturing method using the same. Background Technology

[0002] A semiconductor device such as a DRAM (Dynamic Random Access Memory) has wiring such as a MOS transistor including a source and a drain, a capacitor electrically connected to the source of the MOS transistor, and a bit line electrically connected to the drain of the MOS transistor.

[0003] In such DRAMs, a 3D structure that deviates from the 2D structure has been proposed in accordance with the trend of high integration.

[0004] 3D DRAM is an alternative that can overcome the limitations of miniaturization and high integration of 2D DRAM by separating and individually configuring transistors and capacitors based on stacked isolation insulating layers and memory cell layers that alternate in the vertical direction. Technology regarding such 3D DRAM is disclosed in Korean Registered Patent No. 10-2334784.

[0005] However, 3D DRAM has a problem in that it is difficult to apply the activation method in which a laser is irradiated in the vertical direction in 2D DRAM to a high-concentration semiconductor film that has a 3D structure and is used as the source or drain of a transistor.

[0006] Accordingly, there is a need to propose a technology for activating high-concentration semiconductor films in 3D DRAMs having a 3D structure. The problem to be solved

[0008] One embodiment proposes a method for activating a high-concentration semiconductor film exposed in a direction other than the laser irradiation direction in a three-dimensional DRAM or semiconductor structure having a three-dimensional structure.

[0009] At this time, some embodiments propose a method to prevent a reaction caused by direct contact with another film during the process of activating a high-concentration semiconductor film.

[0010] In addition, some embodiments propose a method to prevent other regions excluding the high-concentration semiconductor film from being affected in a three-dimensional DRAM or semiconductor structure during the process of activating the high-concentration semiconductor film.

[0011] However, the technical problems that the present invention aims to solve are not limited to the above problems and can be expanded in various ways without departing from the technical concept and scope of the present invention. means of solving the problem

[0012] According to one embodiment, a method for manufacturing a three-dimensional memory for activating a high-concentration semiconductor film in a semiconductor structure having a three-dimensional structure comprises: preparing a semiconductor structure in which a part of a transistor is formed, including alternately stacked isolation insulating layers and memory cell layers in a vertical direction; etching a part of each of the memory cell layers in a horizontal direction so that a region corresponding to the channel of the transistor remains; forming a high-concentration semiconductor film used as a source or drain of the transistor on a surface where a region corresponding to the channel of the transistor is exposed through each of the spaces where a part of each of the memory cell layers is etched; forming a thermal conductive film so as to be in contact with the high-concentration semiconductor film exposed in the horizontal direction and simultaneously in contact with a surface corresponding to the vertical direction where a laser is irradiated from the semiconductor structure; and activating the high-concentration semiconductor film by transferring heat through the thermal conductive film to the high-concentration semiconductor film in response to laser annealing being performed on the semiconductor structure.

[0013] According to one aspect, the step of forming the thermal conductive film may include: forming a reaction barrier so as to be in direct contact with the high-concentration semiconductor film—the reaction barrier prevents a reaction resulting from the high-concentration semiconductor film being in direct contact with the thermal conductive film when the laser annealing is performed—and forming the thermal conductive film so as to be indirectly contacted with the high-concentration semiconductor film through the reaction barrier.

[0014] According to another aspect, the reaction barrier may be formed with a thickness and material that transfers heat from the heat-conducting film to the high-concentration semiconductor film during laser annealing, while simultaneously preventing a reaction caused by the high-concentration semiconductor film coming into direct contact with the heat-conducting film during laser annealing.

[0015] According to another aspect, the step of preparing the semiconductor structure may further include the step of forming a heat conduction barrier film on an upper surface corresponding to the vertical direction in the semiconductor structure to prevent heat from being transferred through the heat conduction film to a region other than the high-concentration semiconductor film.

[0016] According to another aspect, the heat conduction barrier may be formed with a thickness and material that minimizes the transfer of heat through the heat conduction barrier to areas other than the high-concentration semiconductor film when the laser annealing is performed.

[0017] According to another aspect, the step of preparing the semiconductor structure may further include the step of forming a laser transmission barrier film on an upper surface corresponding to the vertical direction in the semiconductor structure to prevent the laser from being transmitted to other regions excluding the high-concentration semiconductor film.

[0018] According to another aspect, the laser transmission barrier may be formed with a thickness and material that minimizes the transmittance of the laser when the laser annealing is performed.

[0019] According to another aspect, the method for manufacturing a three-dimensional memory may further include the steps of: removing the thermal conductive film; forming first horizontal electrodes of the capacitor in spaces where a portion of each of the memory cell layers is etched; etching a portion of each of the separating insulating layers in the horizontal direction; forming a dielectric film of the capacitor on the upper, side, and lower surfaces of the spaces where a portion of each of the separating insulating layers is etched; and forming second horizontal electrodes of the capacitor in the spaces where the dielectric film of the capacitor is formed and forming a vertical electrode connecting the second horizontal electrodes of the capacitor.

[0020] According to one embodiment, a method for activating a high-concentration semiconductor film in a semiconductor structure having a three-dimensional structure may include: a step of preparing a semiconductor structure including a high-concentration semiconductor film exposed in a first direction; a step of forming a thermal conductive film so as to be in contact with the high-concentration semiconductor film exposed in the first direction and simultaneously in contact with a surface corresponding to a second direction in which a laser is irradiated from the semiconductor structure; and a step of activating the high-concentration semiconductor film by transferring heat through the thermal conductive film to the high-concentration semiconductor film in response to laser annealing being performed by irradiating the laser in the second direction.

[0021] According to one aspect, the step of forming the thermal conductive film may include: forming a reaction barrier so as to be in direct contact with the high-concentration semiconductor film—the reaction barrier prevents a reaction resulting from the high-concentration semiconductor film being in direct contact with the thermal conductive film during laser annealing; and forming the thermal conductive film so as to be indirectly contacted with the high-concentration semiconductor film through the reaction barrier.

[0022] According to another aspect, the reaction barrier may be formed with a thickness and material that transfers heat from the heat-conducting film to the high-concentration semiconductor film during laser annealing, while simultaneously preventing a reaction caused by the high-concentration semiconductor film coming into direct contact with the heat-conducting film during laser annealing.

[0023] According to another aspect, the step of preparing the semiconductor structure may further include the step of forming a heat conduction barrier film on a surface corresponding to the second direction in the semiconductor structure to prevent heat from being transferred through the heat conduction film to a region other than the high-concentration semiconductor film.

[0024] According to another aspect, the heat conduction barrier may be formed with a thickness and material that minimizes the transfer of heat through the heat conduction barrier to areas other than the high-concentration semiconductor film when the laser annealing is performed.

[0025] According to another aspect, the step of preparing the semiconductor structure may further include the step of forming a laser transmission barrier film on a surface corresponding to the second direction in the semiconductor structure to prevent the laser from being transmitted to a region other than the high-concentration semiconductor film.

[0026] According to another aspect, the laser transmission barrier may be formed with a thickness and material that minimizes the transmittance of the laser when the laser annealing is performed. Effects of the invention

[0027] One embodiment may propose a method for activating a high-concentration semiconductor film exposed in a direction other than the laser irradiation direction in a 3D DRAM or semiconductor structure having a 3D structure.

[0028] At this time, some embodiments may propose a method to prevent a reaction caused by direct contact with another film during the process of activating a high-concentration semiconductor film.

[0029] In addition, some embodiments may propose a method to prevent other regions excluding the high-concentration semiconductor film from being affected in a three-dimensional DRAM or semiconductor structure during the process of activating the high-concentration semiconductor film.

[0030] However, the effects of the present invention are not limited to the above effects and can be extended in various ways without departing from the technical concept and scope of the present invention. Brief explanation of the drawing

[0032] FIG. 1 is a flowchart illustrating a method for manufacturing a three-dimensional memory according to one embodiment. FIGS. 2a to 2r are plan views illustrating a three-dimensional memory to explain the method for manufacturing a three-dimensional memory illustrated in FIG. 1. FIGS. 3a to 3r are side cross-sectional views illustrating a three-dimensional memory to explain the method of manufacturing a three-dimensional memory illustrated in FIG. 1, corresponding to the cross-section obtained by cutting FIGS. 2a to 2r along the line A-A'. FIGS. 4a to 4g are side cross-sectional views illustrating a three-dimensional memory to explain a method for manufacturing a three-dimensional memory using a laser transmission barrier film, corresponding to the cross-section cut along the line A-A' of FIGS. 2b to 2h. FIG. 5 is a flowchart illustrating a high-concentration semiconductor film activation method according to one embodiment. Specific details for implementing the invention

[0033] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited or restricted by the embodiments. Also, the same reference numerals in each drawing indicate the same components.

[0034] Furthermore, the terminology used in this specification is used to appropriately describe preferred embodiments of the present invention, and may vary depending on the intent of the viewer or operator, or the conventions of the field to which the present invention belongs. Accordingly, the definitions of these terms should be based on the content throughout this specification. For example, in this specification, the singular form includes the plural form unless specifically stated otherwise in the text. Also, the terms "comprises" and / or "comprising" used in this specification do not exclude the presence or addition of one or more other components, steps, actions, and / or elements to the mentioned components, steps, actions, and / or elements. Additionally, although terms such as "first," "second," etc., are used in this specification to describe various regions, directions, shapes, etc., these regions, directions, and shapes should not be limited by such terms. These terms are used merely to distinguish one specific region, direction, or shape from another region, direction, or shape. Accordingly, a part referred to as the first part in one embodiment may be referred to as the second part in another embodiment.

[0035] Furthermore, it should be understood that various embodiments of the present invention are different but need not be mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in other embodiments without departing from the technical spirit and scope of the present invention in relation to one embodiment. Additionally, it should be understood that the location, arrangement, or configuration of individual components within each presented category of embodiments may be changed without departing from the technical spirit and scope of the present invention.

[0036] Hereinafter, a method for activating a high-concentration semiconductor film according to embodiments and a method for manufacturing a three-dimensional memory using the same will be described in detail with reference to the drawings.

[0038] FIG. 1 is a flowchart illustrating a method for manufacturing a three-dimensional memory according to one embodiment, FIG. 2a to 2r are plan views illustrating a three-dimensional memory to explain the method for manufacturing a three-dimensional memory illustrated in FIG. 1, FIG. 3a to 3r are side cross-sectional views illustrating a three-dimensional memory to explain the method for manufacturing a three-dimensional memory illustrated in FIG. 1, corresponding to the cross-section cut along the A-A' line of FIG. 2a to 2r, FIG. 4a to 4g are side cross-sectional views illustrating a three-dimensional memory to explain a method for manufacturing a three-dimensional memory that further utilizes a laser transmission barrier, corresponding to the cross-section cut along the A-A' line of FIG. 2b to 2h.

[0039] The 3D memory manufacturing method described below relates to a method for manufacturing a 3D memory while performing a method of activating a high-concentration semiconductor film (HSF 1, HSF 2) exposed in a direction other than the laser irradiation direction, and is performed on the premise that it is carried out by an automated and mechanized manufacturing system.

[0040] Referring to the drawings, in step (S110), the manufacturing system can prepare a semiconductor structure (SEMI-STR) in which part of a transistor (TR) is formed, including vertically alternately stacked isolation insulating layers (ILD-L) and memory cell layers (MEM-L).

[0041] The semiconductor structure (SEMI-STR) described below may be formed on a substrate (not shown), but for the sake of convenience of explanation, the substrate will be omitted.

[0042] Here, the isolation insulating layers (ILD-L) can be formed of insulating materials such as low dielectric constant oxide films such as SiO2, Si3N4, and SiON, and the memory cell layers (MEM-L) can be formed of materials such as Si, SiGe, SiC, or Si doped with Ge, B, or P that can be grown as a single crystal.

[0043] Each of the isolation insulating layers (ILD-L) and memory cell layers (MEM-L) is etched and recessed in the horizontal direction through different processes in the steps described below, so that they can each be formed of materials with different etching selectivity ratios.

[0044] For example, as shown in FIGS. 2a and 3a, the manufacturing system can prepare a semiconductor structure (SEMI-STR) including a region (CA) corresponding to the channel (C) of the transistor (TR), with the region (TR-A) where the transistor (TR) is to be formed and the region (CAP-A) where the capacitor (CAP) is to be formed separated.

[0045] At this time, the semiconductor structure (SEMI-STR) may include a gate (G) and a gate insulating film (GD) that are in contact with the side of a region (CA) corresponding to the channel (C).

[0046] Additionally, the semiconductor structure (SEMI-STR) may further include a bit line (BL) penetrating the separation insulating layers (ILD-L) and memory cell layers (MEM-L) in a vertical direction, and an activated high-concentration semiconductor film (A-HSF 2) in contact with the side of the bit line (BL) at each of the memory cell layers (MEM-L). The bit line (BL) may be formed from high-concentration silicon or any one of metal materials such as W, Mo, Ru, or Co, and may further include an ohmic film (not shown) formed from metal silicide, etc. at the contact area with the memory cell layers (MEM-L) during the formation process.

[0047] The activated high-concentration semiconductor film (A-HSF 2) in contact with the side of the bit line (BL) in each of the memory cell layers (MEM-L) may be a portion used as the drain (DR) of the transistor (TR) and may be activated through the steps (S120 to S150) described below. A detailed description thereof will be provided after the process of activating the high-concentration semiconductor film (HSF 1), which is a portion used as the source (S) of the transistor (TR) through the steps (S120 to S150), is described.

[0048] Additionally, in step (S110), the manufacturing system can form a thermal conduction barrier film (TCBF) on the upper surface corresponding to the vertical direction of the semiconductor structure (SEMI-STR), as shown in FIGS. 2b and FIGS. 3b.

[0049] The thermal conduction barrier film (TCBF) is a component that prevents heat from being transferred to other regions excluding the high-concentration semiconductor film (HSF 1) as laser annealing is performed in step (S150), and can be formed with a thickness and material that minimizes the transfer of heat through the thermal conduction film (TCF) to other regions excluding the high-concentration semiconductor film (HSF 1) in the semiconductor structure (SEMI-STR) when laser annealing is performed. For example, the thermal conduction barrier film (TCBF) can be formed with a thickness of 10 nm to 500 nm using a material such as a silicon nitride film.

[0050] In addition, the thermal conduction barrier film (TCBF) can serve to prevent heat from being transferred not only through the thermal conduction film (TCF) to areas other than the high-concentration semiconductor film (HSF 1) in the semiconductor structure (SEMI-STR) during laser annealing, but also through other structures such as the bit line (BL).

[0051] Here, since the thermal conduction barrier film (TCBF) must remain without being removed from the semiconductor structure (SEMI-STR) until the laser annealing process performed in step (S150), it may be formed of a material with a different etching selectivity from the memory cell layers (MEM-L) so that it is not etched together with the memory cell layers (MEM-L) during the process in which a portion of each memory cell layer (MEM-L) is etched in step (S120).

[0052] In addition, the thermal conduction barrier film (TCBF) may be formed of a material with a different etching selectivity from the reaction barrier film (RBF) so that the reaction barrier film (RBF), which is formed before the thermal conduction film (TCF) in the step (S140) described later, is not removed together with the thermal conduction film (TCF) during the process of removing the reaction barrier film (RBF) together with the thermal conduction film (TCF).

[0053] In addition, the thermal conduction barrier film (TCBF) may be formed of a material with a different etching selectivity from the separated insulating layers (ILD-L) so that it is not etched together with the separated insulating layers (ILD-L) in the process in which the dielectric film (CD) of the capacitor (CAP) is formed after the step (S150) described later.

[0054] Although it has been described that a thermal conduction barrier film (TCBF) is formed on the semiconductor structure (SEMI-STR), it is not limited thereto, and in step (S110), the manufacturing system may form a laser transmission barrier film (LPBF) on the upper surface corresponding to the vertical direction of the semiconductor structure (SEMI-STR) to prevent laser transmission to other regions excluding the high-concentration semiconductor film (HSF 1) in the semiconductor structure (SEMI-STR), as shown in FIG. 4a.

[0055] The laser transmission barrier (LPBF) is a component that prevents the laser from being transmitted to other regions of the semiconductor structure (SEMI-STR), excluding the high-concentration semiconductor film (HSF 1), when laser annealing is performed in step (S150), and can be formed with a thickness and material that minimizes the transmittance of the laser when laser annealing is performed. For example, the laser transmission barrier (LPBF) can be formed with a thickness of 3 nm to 500 nm using at least one of a metal material such as Au Ag, Ti, Ta, Co, CoSi, Ni, NiSi, Ru, W, WSi, Cu, Re, Mo, Nb, Cr, Pd, Mg, Li, or at least one of metal nitride films such as Au Ag, Ti, Ta, Co, CoSi, Ni, NiSi, Ru, W, WSi, Cu, Re, Mo, Nb, Cr, Pd, Mg, Li.

[0056] In step (S120), the manufacturing system can etch a portion of each of the memory cell layers (MEM-L) in a horizontal direction so that a region (CA) corresponding to the channel (C) of the transistor (TR) remains.

[0057] More specifically, the manufacturing system can form a vertical hole (VH1) in the vertical direction in the semiconductor structure (SEMI-STR) as shown in FIG. 2c and 3c or FIG. 4b, and then recess a portion of each memory cell layer (MEM-L) in the horizontal direction through the vertical hole (VH1) as shown in FIG. 2d and 3d or FIG. 4c, thereby leaving a region (CA) corresponding to the channel (C) of the transistor (TR).

[0058] Fluorine-based dry etching processes including CF4, SF6, etc., or chlorine-based dry etching processes including Cl2, CCl4, etc., may be used as the etching method for the vertical hole (VH1), and wet etching processes based on KOH, TMAH, etc., may be used as the recessing method for a portion of each of the memory cell layers (MEM-L).

[0059] In step (S130), the manufacturing system can form a high-concentration semiconductor film (HSF 1) used as a source (S) of a transistor (TR) on a surface where a region (CA) corresponding to the channel (C) of a transistor (TR) is exposed through each of the etched regions of each of the memory cell layers (MEM-L).

[0060] For example, as shown in FIG. 2e and 3e or FIG. 4d, the manufacturing system has N-type impurities containing As or P at 1E20 / cm² on the surface where the region (CA) corresponding to the channel (C) of the transistor (TR) is exposed through each of the etched spaces of each of the memory cell layers (MEM-L). 3 A high concentration semiconductor film (HSF 1) can be formed using silicon or silicon germanium doped with the above doping concentration. A remote plasma technique can be used as the doping method.

[0061] However, the high concentration semiconductor film (HSF 1) can be formed not only through N-type impurity doping but also through P-type impurity doping, or through selective deposition of high concentration silicon or silicon germanium.

[0062] In step (S140), the manufacturing system can form a thermal conductive film (TCF) that contacts a high-concentration semiconductor film (HSF 1) exposed in the horizontal direction, and at the same time contacts a surface corresponding to the vertical direction in which a laser is irradiated from the semiconductor structure (SEMI-STR).

[0063] More specifically, in step (S140), the manufacturing system may form a reaction barrier film (RBF) to be in direct contact with the high-concentration semiconductor film (HSF 1) as shown in FIG. 2f and FIG. 3f or FIG. 4e, and then form a thermal conductive film (TCF) to be indirectly contacted with the high-concentration semiconductor film (HSF 1) through the reaction barrier film (RBF) as shown in FIG. 2g and FIG. 3g or FIG. 4f.

[0064] The reaction barrier film (RBF) is a component that prevents the high-concentration semiconductor film (HSF 1) from reacting with the thermal conductive film (TCF) when the high-concentration semiconductor film (HSF 1) comes into direct contact with the thermal conductive film (TCF) during laser annealing in step (S150). It can be formed with a thickness and material that transfers heat from the thermal conductive film (TCF) to the high-concentration semiconductor film (HSF 1) during laser annealing, while simultaneously preventing the reaction caused by the high-concentration semiconductor film (HSF 1) coming into direct contact with the thermal conductive film (TCF) during laser annealing. For example, the reaction barrier film (RBF) can be formed with a thickness of 1 nm to 3 nm using a silicon oxide film, a silicon nitride film, or an aluminum oxide film.

[0065] Here, the reaction between the high concentration semiconductor film (HSF 1) and the thermal conductive film (TCF) as the high concentration semiconductor film (HSF 1) comes into direct contact with the thermal conductive film (TCF) can refer to both physical and chemical reactions, such as doping material or ions from the high concentration semiconductor film (HSF 1) moving out to the thermal conductive film (TCF) or ions from the thermal conductive film (TCF) moving into the high concentration semiconductor film (HSF 1).

[0066] The thermal conductive film (TCF) is a component that transfers heat from the laser irradiated during laser annealing in step (S150) to the high-concentration semiconductor film (HSF 1). It can be formed with a thickness of 1.5 nm to 50 nm using at least one of high-concentration doped silicon with a thermal conductivity greater than a preset level, or a metallic material including Mo, Ti, Ru, Co, etc. The thermal conductivity, constituent material, or thickness of the thermal conductive film (TCF) can be selected, set, and controlled to satisfy conditions in which sufficient heat is transferred from the laser irradiation to activate the high-concentration semiconductor film (HSF 1). Additionally, since the thermal conductive film (TCF) is also deposited within the aforementioned vertical hole (VH1), the thickness of the thermal conductive film (TCF) must satisfy the condition that it does not exceed half the planar width of the maximum vertical hole (VH1).

[0067] In step (S150), the manufacturing system can complete the activated high-concentration semiconductor film (A-HSF 1) by activating the high-concentration semiconductor film (HSF 1) through the heat conductive film (TCF) in response to laser annealing being performed on the semiconductor structure (SEMI-STR).

[0068] For example, as shown in FIG. 2h and 3h or FIG. 4g, the manufacturing system has a wavelength band of 0.01 μm to 50 μm, a pulse width of 1 ns to 1,000 ns, and 1 mJ / cm² in a direction perpendicular to the upper surface of a semiconductor structure (SEMI-STR). 2 Up to 2000 mJ / cm 2 Heat can be transferred to a high-concentration semiconductor film (HSF 1) through a thermal conductive film (TCF) by irradiating with a laser such as a YAG or CO2 laser having an energy density per pulse. Accordingly, the high-concentration semiconductor film (HSF 1) can be activated by the heat conducted through the thermal conductive film (TCF).

[0069] As described above, a reaction barrier film (RBF) that transmits only heat from laser annealing is interposed between the high concentration semiconductor film (HSF 1) and the thermal conductive film (TCF), so that the reaction between the high concentration semiconductor film (HSF 1) and the thermal conductive film (TCF) can be prevented during the activation process of the high concentration semiconductor film (HSF 1).

[0070] In addition, as described above, a thermal conduction barrier film (TCBF) is disposed on the upper surface of the semiconductor structure (SEMI-STR), so that heat through the thermal conduction film (TCF) resulting from laser annealing during the activation process of the high-concentration semiconductor film (HSF 1) can be prevented from being transferred to other areas of the semiconductor structure (SEMI-STR) excluding the high-concentration semiconductor film (HSF 1).

[0071] In addition, as described above, a laser transmission barrier (LPBF) is disposed on the upper surface of the semiconductor structure (SEMI-STR), so that during the activation process of the high-concentration semiconductor film (HSF 1), the laser can be prevented from being transmitted to other areas of the semiconductor structure (SEMI-STR) excluding the high-concentration semiconductor film (HSF 1).

[0072] As such, the method for manufacturing a three-dimensional memory according to one embodiment can enable the manufacturing of a three-dimensional memory by using a thermal conductive film (TCF) to activate a high-concentration semiconductor film (HSF 1) exposed in a direction other than the direction of laser irradiation, and can prevent a reaction caused by the high-concentration semiconductor film (HSF 1) coming into direct contact with another film (thermal conductive film (TCF)) during the activation process of the high-concentration semiconductor film (HSF 1) by using a reaction barrier film (RBF), and can prevent other regions excluding the high-concentration semiconductor film (HSF 1) from being affected by transferred heat or transmitted laser during the activation process of the high-concentration semiconductor film (HSF 1) by using a thermal conductive barrier film (TCBF) and / or a laser transmission barrier film (LPBF).

[0073] Although not illustrated as a separate step in FIG. 1, the manufacturing system can complete the formation of transistors (TR) and capacitors (CAP) on a semiconductor structure (SEMI-STR) through subsequent steps.

[0074] For example, in the first subsequent step after step (S150), the manufacturing system may remove the thermal conductive film (TCF) and the reaction barrier film (RBF) as illustrated in FIGS. 2i and FIGS. 3i. At this time, if a laser transmission barrier film (LPBF) is present, the manufacturing system may also remove the laser transmission barrier film (LPBF) in the first subsequent step.

[0075] In a second subsequent step, the manufacturing system can form first horizontal electrodes (HE1) of a capacitor (CAP) in the spaces where a portion of each of the memory cell layers (MEM-L) is etched, as shown in FIGS. 2j and 3j. The first horizontal electrodes (HE1) can be formed of a metallic material such as Ru, Co, Ti, TiN, etc.

[0076] In the third subsequent step, the manufacturing system can etch a portion of each of the isolated insulating layers (ILD-L) in a horizontal direction as shown in FIGS. 2k and FIGS. 3k. For the etching (recessing) method of each portion of the isolated insulating layers (ILD-L), a wet etching process based on KOH, TMAH, etc., may be used.

[0077] At this time, the depth to which a portion of each of the isolation insulating layers (ILD-L) is etched and recessed in the horizontal direction can be determined according to the location of the activated high-concentration semiconductor film (A-HSF 1) included in the memory cell layers (MEM-L). For example, the depth to which a portion of each of the isolation insulating layers (ILD-L) is etched and recessed in the horizontal direction can be determined to a depth not deeper than the location of the activated high-concentration semiconductor film (A-HSF 1) included in the memory cell layers (MEM-L) (a depth at which the activated high-concentration semiconductor film (A-HSF 1) included in the memory cell layers (MEM-L) is not exposed).

[0078] In the fourth subsequent step, the manufacturing system can form a dielectric film (CD) of the capacitor (CAP) on the upper, side, and lower surfaces of the etched areas of each of the separated insulating layers (ILD-L), as illustrated in FIGS. 2L and 3L. Since the upper, side, and lower surfaces of the etched areas of each of the separated insulating layers (ILD-L) are in contact with the lower, side, and upper surfaces of the first horizontal electrodes (HE1) of the capacitor (CAP), the dielectric film (CD) of the capacitor can be formed by surrounding the lower, side, and upper surfaces of the first horizontal electrodes (HE1) of the capacitor (CAP) with a dielectric material such as HfO2, ZrO2, SiO2, Al2O3, TiO2, etc.

[0079] In the fifth subsequent step, the manufacturing system may form second horizontal electrodes (HE2) of the capacitor (CAP) in the spaces where the dielectric film (CD) of the capacitor (CAP) is formed as shown in FIGS. 2m and FIGS. 3m, and form a vertical electrode (VE) connecting the second horizontal electrodes (HE) of the capacitor (CAP). The second horizontal electrodes (HE2) may be formed of a metallic material such as Ru, Co, Ti, TiN, etc.

[0081] Although the process of activating the high-concentration semiconductor film (HSF 1), which is the part used as the source (S) of the transistor (TR) in each of the memory cell layers (MEM-L), has been described through the above steps (S120 to S150), the high-concentration semiconductor film (HSF 2), which is used as the drain (DR) of the transistor (TR) in each of the memory cell layers (MEM-L), can also be activated through the same steps.

[0082] For example, in step (S110), the manufacturing system may prepare a semiconductor structure (SEMI-STR) comprising a gate (G) and a gate insulating film (GD) in contact with the side of a region (CA) corresponding to a channel (C), and a region (CA) corresponding to the channel (C) of the transistor (TR), with the region (TR-A) to be formed and the region (CAP-A) to be formed of the capacitor (CAP) separated as shown in FIGS. 2n and 3n. Subsequently, in step (S120), the manufacturing system may form a vertical hole (VH2) as shown in FIGS. 2o and 3o, and etch a portion of each of the memory cell layers (MEM-L) in a horizontal direction so that the region (CA) corresponding to the channel (C) of the transistor (TR) remains through the vertical hole (VH2). The manufacturing system can then form a high-concentration semiconductor film (HSF 2) in step (S130) that is used as the drain (DR) of the transistor (TR) on the exposed surface where the region (CA) corresponding to the channel (C) of the transistor (TR) is exposed through each of the etched regions of each of the memory cell layers (MEM-L) as illustrated in FIGS. 2p and FIGS. 3p. The manufacturing system can then form a thermal conductive film (TCF) in step (S140) that is in contact with the horizontally exposed high-concentration semiconductor film (HSF 2) and simultaneously in contact with the vertically oriented surface where a laser is irradiated from the semiconductor structure (SEMI-STR). Afterward, the manufacturing system can complete the activated high-concentration semiconductor film (A-HSF 2) by transferring heat through the thermal conductive film (TCF) to the high-concentration semiconductor film (HSF 1) in response to laser annealing being performed on the semiconductor structure (SEMI-STR) as illustrated in FIGS. 2r and FIGS. 3r in step (S150), thereby activating the high-concentration semiconductor film (HSF 2).

[0083] Each of the detailed processes of the steps (S110 to S150) in the process of activating the high-concentration semiconductor film (HSF 2) may also be identical to each of the detailed processes of the steps (S110 to S150) in the process of activating the high-concentration semiconductor film (HSF 1) described above. For example, in the process of activating a high-concentration semiconductor film (HSF 2), a reaction barrier film (RBF) (not shown in FIGS. 2n to 2r and FIGS. 3n to 3r, but the reaction barrier film (RBF) is interposed between the high-concentration semiconductor film (HSF 2) and the thermal conductive film (TCF)) can be used to prevent a reaction caused by the high-concentration semiconductor film (HSF 2) coming into direct contact with another film (thermal conductive film (TCF)), and a thermal conductive barrier film (TCBF) and / or a laser transmission barrier film (LPBF) formed on the upper surface corresponding to the vertical direction in the semiconductor structure (SEMI-STR) (the thermal conductive barrier film (TCBF) and / or the laser transmission barrier film (LPBF) is not shown in FIGS. 2n to 2r and FIGS. 3n to 3r) can be used so that during the activation process of the high-concentration semiconductor film (HSF 2), other regions excluding the high-concentration semiconductor film (HSF 2) It is possible to prevent it from being affected by heat transfer or transmitted laser. Since these details have been described in detail through the process of activating the high-concentration semiconductor film (HSF 1), a detailed explanation thereof will be omitted.

[0085] In addition, the high-concentration semiconductor film activation process described in the above 3D memory manufacturing method is a technique for activating high-concentration semiconductor films (HSF 1, HSF 2) exposed in a direction other than the laser irradiation direction, and can be applied not only to the manufacturing process of 3D memory but also to other semiconductor manufacturing processes.

[0086] That is, the high-concentration semiconductor film activation process described in the above 3D memory manufacturing method can be generalized to a high-concentration semiconductor film activation method in a semiconductor with a 3D structure in which the high-concentration semiconductor film (HSF 1, HSF 2) is exposed in a direction other than the laser irradiation direction. A detailed explanation thereof will be provided with reference to FIG. 6.

[0088] FIG. 5 is a flowchart illustrating a high-concentration semiconductor film activation method according to one embodiment.

[0089] The high-concentration semiconductor film activation method described below is a method for activating a high-concentration semiconductor film (HSF) exposed in a direction other than the laser irradiation direction, and is performed on the premise that it is carried out by an automated and mechanized manufacturing system.

[0090] Referring to the drawings, in step (S510), the manufacturing system can prepare a semiconductor structure (SEMI-STR) including a high concentration semiconductor film (HSF) exposed in a first direction.

[0091] Additionally, in step (S510), the manufacturing system can form a thermal conduction barrier film (TCBF) on a surface corresponding to a second direction in the semiconductor structure (SEMI-STR).

[0092] The thermal conduction barrier film (TCBF) is a component that prevents heat from being transferred to other regions excluding the high-concentration semiconductor film (HSF) as laser annealing is performed in step (S530), and can be formed with a thickness and material that minimizes the transfer of heat through the thermal conduction barrier film (TCF) to other regions excluding the high-concentration semiconductor film (HSF) in the semiconductor structure (SEMI-STR) when laser annealing is performed. For example, the thermal conduction barrier film (TCBF) can be formed with a thickness of 10 nm to 500 nm using a material such as a silicon nitride film.

[0093] In addition, the thermal conduction barrier (TCBF) can play a role in preventing heat from being transferred not only through the thermal conduction barrier (TCF) but also through other structures in areas of the semiconductor structure (SEMI-STR) other than the high-concentration semiconductor film (HSF) during laser annealing.

[0094] Additionally, in step (S510), the manufacturing system may form a laser transmission barrier film (LPBF) on a surface corresponding to a second direction in the semiconductor structure (SEMI-STR) to prevent the laser from being transmitted to other regions of the semiconductor structure (SEMI-STR), excluding the high concentration semiconductor film (HSF).

[0095] The laser transmission barrier (LPBF) is a component that prevents the laser from being transmitted to other regions of the semiconductor structure (SEMI-STR), excluding the high-concentration semiconductor film (HSF), when laser annealing is performed in step (S530), and can be formed with a thickness and material that minimizes the transmittance of the laser when laser annealing is performed. For example, the laser transmission barrier (LPBF) can be formed with a thickness of 10 nm to 500 nm using at least one metal material such as Au, Cr, Ni, W, Ti, Pd, Mg, Li, or at least one metal nitride film such as Au, Cr, Ni, W, Ti, Pd, Mg, Li.

[0096] In step (S520), the manufacturing system can form a thermal conductive film (TCF) so as to be in contact with a high-concentration semiconductor film (HSF) exposed in a first direction, and at the same time in contact with a surface corresponding to a second direction in which a laser is irradiated from a semiconductor structure (SEMI-STR).

[0097] More specifically, in step (S520), the manufacturing system can form a reaction barrier film (RBF) to be in direct contact with the high concentration semiconductor film (HSF), and then form a thermal conductive film (TCF) to be indirectly contacted with the high concentration semiconductor film (HSF) through the reaction barrier film (RBF).

[0098] The reaction barrier film (RBF) is a component that prevents the high-concentration semiconductor film (HSF) from reacting with the thermal conductive film (TCF) when the high-concentration semiconductor film (HSF) comes into direct contact with the thermal conductive film (TCF) during laser annealing in step (S530). It can be formed with a thickness and material that transfers heat from the thermal conductive film (TCF) to the high-concentration semiconductor film (HSF) during laser annealing, while simultaneously preventing the reaction caused by the high-concentration semiconductor film (HSF) coming into direct contact with the thermal conductive film (TCF) during laser annealing. For example, the reaction barrier film (RBF) can be formed with a thickness of 1 nm to 3 nm using a silicon oxide film, a silicon nitride film, or an aluminum oxide film.

[0099] The thermal conductive film (TCF) is a component that transfers heat from the laser irradiated during laser annealing in step (S530) to the high-concentration semiconductor film (HSF), and can be formed with a thickness of 1.5 nm to 50 nm using at least one of high-concentration doped silicon with a thermal conductivity greater than a preset level, or a metal material including Mo, Ti, Ru, Co, etc. The thermal conductivity, constituent material, or thickness of the thermal conductive film (TCF) can be selected, set, and adjusted to satisfy conditions in which heat from laser irradiation is sufficiently transferred to activate the high-concentration semiconductor film (HSF).

[0100] In step (S530), the manufacturing system can activate the high-concentration semiconductor film (HSF) by transferring heat through the thermal conductive film (TCF) to the high-concentration semiconductor film (HSF) in response to laser annealing being performed by irradiating a laser in a second direction.

[0101] For example, the manufacturing system has a wavelength band of 0.01 µm to 50 µm, a pulse width of 1 ns to 1,000 ns, and 1 mJ / cm² in the second direction of a semiconductor structure (SEMI-STR). 2 Up to 2000 mJ / cm 2Heat can be transferred to a high-concentration semiconductor film (HSF) through a thermal conductive film (TCF) by irradiating with a laser such as a YAG or CO2 laser having an energy density per pulse. Accordingly, the high-concentration semiconductor film (HSF) can be activated by the heat conducted through the thermal conductive film (TCF).

[0102] As described above, a reaction barrier film (RBF) that transmits only heat from laser annealing is interposed between the high concentration semiconductor film (HSF) and the thermal conductive film (TCF), so that the reaction between the high concentration semiconductor film (HSF) and the thermal conductive film (TCF) can be prevented during the activation process of the high concentration semiconductor film (HSF).

[0103] In addition, as described above, a thermal conduction barrier film (TCBF) is disposed on the surface corresponding to the second direction of the semiconductor structure (SEMI-STR), so that heat through the thermal conduction film (TCF) resulting from laser annealing during the activation process of the high-concentration semiconductor film (HSF) can be prevented from being transferred to other areas of the semiconductor structure (SEMI-STR) excluding the high-concentration semiconductor film (HSF).

[0104] In addition, as described above, a laser transmission barrier (LPBF) is disposed on the surface corresponding to the second direction of the semiconductor structure (SEMI-STR), so that during the activation process of the high-concentration semiconductor film (HSF), the laser can be prevented from being transmitted to other areas of the semiconductor structure (SEMI-STR) excluding the high-concentration semiconductor film (HSF).

[0105] As such, the high-concentration semiconductor film activation method according to one embodiment can activate a high-concentration semiconductor film (HSF) exposed in a direction other than the laser irradiation direction (second direction) by using a thermal conductive film (TCF), and can be utilized in a semiconductor process with a three-dimensional structure. In addition, by using a reaction barrier film (RBF), a reaction can be prevented by the high-concentration semiconductor film (HSF) coming into direct contact with another film (thermal conductive film (TCF)) during the activation process of the high-concentration semiconductor film (HSF). Furthermore, by using a thermal conductive barrier film (TCBF) and / or a laser transmission barrier film (LPBF), other regions excluding the high-concentration semiconductor film (HSF) can be prevented from being affected by transferred heat or transmitted laser during the activation process of the high-concentration semiconductor film (HSF).

[0107] Although the embodiments have been described above with reference to limited examples and drawings, those skilled in the art can make various modifications and variations from the description above. For example, suitable results can be achieved even if the described techniques are performed in a different order than described, and / or the components of the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents.

[0108] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

Claim 1 A method for manufacturing a three-dimensional memory for activating a high-concentration semiconductor film in a semiconductor structure having a three-dimensional structure, comprising: a step of preparing a semiconductor structure in which a part of a transistor is formed, including alternately stacked insulating layers and memory cell layers in a vertical direction; a step of etching a part of each of the memory cell layers in a horizontal direction so that a region corresponding to the channel of the transistor remains; a step of forming a high-concentration semiconductor film used as a source or drain of the transistor on a surface where a region corresponding to the channel of the transistor is exposed through each of the spaces where a part of each of the memory cell layers is etched; a step of forming a thermal conductive film so as to be in contact with the high-concentration semiconductor film exposed in the horizontal direction and simultaneously in contact with a surface corresponding to the vertical direction where a laser is irradiated from the semiconductor structure; and a step of activating the high-concentration semiconductor film by transferring heat through the thermal conductive film to the high-concentration semiconductor film in response to laser annealing being performed on the semiconductor structure. Claim 2 A method for manufacturing a three-dimensional memory according to claim 1, wherein the step of forming the thermal conductive film comprises: a step of forming a reaction barrier so as to be in direct contact with the high-concentration semiconductor film—the reaction barrier prevents a reaction resulting from the high-concentration semiconductor film being in direct contact with the thermal conductive film when the laser annealing is performed—and a step of forming the thermal conductive film so as to be indirectly contacted with the high-concentration semiconductor film through the reaction barrier. Claim 3 A method for manufacturing a three-dimensional memory according to claim 2, wherein the reaction barrier is formed of a thickness and material that transfers heat from the heat-conducting film to the high-concentration semiconductor film during laser annealing, while simultaneously preventing a reaction caused by the high-concentration semiconductor film coming into direct contact with the heat-conducting film during laser annealing. Claim 4 A method for manufacturing a three-dimensional memory according to claim 1, wherein the step of preparing the semiconductor structure further comprises the step of forming a heat conduction barrier film on an upper surface corresponding to the vertical direction in the semiconductor structure to prevent heat from being transferred through the heat conduction film to a region other than the high-concentration semiconductor film. Claim 5 A method for manufacturing a three-dimensional memory according to claim 4, wherein the heat conduction barrier is formed with a thickness and material that minimizes the transfer of heat through the heat conduction barrier to areas other than the high-concentration semiconductor film when the laser annealing is performed. Claim 6 A method for manufacturing a three-dimensional memory according to claim 1, wherein the step of preparing the semiconductor structure further comprises the step of forming a laser transmission blocking film on an upper surface corresponding to the vertical direction in the semiconductor structure to prevent the laser from being transmitted to other regions excluding the high-concentration semiconductor film. Claim 7 A method for manufacturing a three-dimensional memory according to claim 6, wherein the laser transmission barrier is formed of a thickness and material that minimizes the transmittance of the laser when performing the laser annealing. Claim 8 A method for manufacturing a three-dimensional memory according to claim 1, further comprising: a step of removing the thermal conductive film; a step of forming first horizontal electrodes of a capacitor in spaces where a portion of each of the memory cell layers is etched; a step of etching a portion of each of the separating insulating layers in the horizontal direction; a step of forming a dielectric film of a capacitor on the upper, side, and lower surfaces of the spaces where a portion of each of the separating insulating layers is etched; and a step of forming second horizontal electrodes of the capacitor in the spaces where the dielectric film of the capacitor is formed and forming a vertical electrode connecting the second horizontal electrodes of the capacitor. Claim 9 A method for activating a high-concentration semiconductor film in a semiconductor structure having a three-dimensional structure, comprising: a step of preparing a semiconductor structure including a high-concentration semiconductor film exposed in a first direction; a step of forming a thermal conductive film so as to be in contact with the high-concentration semiconductor film exposed in the first direction and simultaneously in contact with a surface corresponding to a second direction in which a laser is irradiated from the semiconductor structure; and a step of activating the high-concentration semiconductor film by transferring heat through the thermal conductive film to the high-concentration semiconductor film in response to laser annealing being performed by irradiating the laser in the second direction. Claim 10 A method for activating a high-concentration semiconductor film according to claim 9, wherein the step of forming the thermal conductive film comprises: a step of forming a reaction barrier so as to be in direct contact with the high-concentration semiconductor film—the reaction barrier prevents a reaction resulting from the high-concentration semiconductor film being in direct contact with the thermal conductive film during laser annealing; and a step of forming the thermal conductive film so as to be indirectly contacted with the high-concentration semiconductor film through the reaction barrier. Claim 11 A method for activating a high-concentration semiconductor film according to claim 10, wherein the reaction barrier is formed of a thickness and material that transfers heat from the heat-conducting film to the high-concentration semiconductor film during laser annealing, while simultaneously preventing a reaction caused by the high-concentration semiconductor film coming into direct contact with the heat-conducting film during laser annealing. Claim 12 A method for activating a high-concentration semiconductor film according to claim 9, wherein the step of preparing the semiconductor structure further comprises the step of forming a heat conduction barrier film on a surface corresponding to the second direction in the semiconductor structure to prevent heat from being transferred through the heat conduction film to a region other than the high-concentration semiconductor film. Claim 13 A method for activating a high-concentration semiconductor film according to claim 12, wherein the heat conduction barrier film is formed with a thickness and material that minimizes the transfer of heat through the heat conduction film to other regions excluding the high-concentration semiconductor film when performing the laser annealing. Claim 14 A method for activating a high-concentration semiconductor film according to claim 9, wherein the step of preparing the semiconductor structure further comprises the step of forming a laser transmission barrier film on a surface corresponding to the second direction in the semiconductor structure to prevent the laser from being transmitted to other regions excluding the high-concentration semiconductor film. Claim 15 A method for activating a high-concentration semiconductor film according to claim 14, wherein the laser transmission barrier is formed of a thickness and material that minimizes the transmittance of the laser when performing the laser annealing.

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