KR-102963351-B1 - A Method of Manufacturing Nitride Semiconductor Device Includes a Single Crystal Aluminum Nitride Thick Film Formed on a Silicon Substrate

KR102963351B1KR 102963351 B1KR102963351 B1KR 102963351B1KR-102963351-B1

Abstract

The present invention relates to a method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate and a single-crystal aluminum nitride thick film, and more specifically, to a method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate by an epitaxial lateral overgrowth (ELO) method by depositing a single-crystal aluminum nitride (AlN) thick film on a silicon substrate having an intaglio pattern formed thereon, thereby preventing crack formation due to differences in lattice constant and coefficient of thermal expansion and improving heat dissipation performance.

Inventors

남옥현
정주철
박주용

Assignees

한국공학대학교산학협력단

Dates

Publication Date: 20260512
Application Date: 20250710
Priority Date: 20241106

Claims (20)

A method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film, (111) A substrate preparation step comprising silicon having a crystalline plane of orientation and a substrate layer having a first intaglio pattern formed on its upper surface; A thick film placement step of placing a thick film layer formed by an epitaxial lateral overgrowth (ELO) method on the substrate layer; and A nitride placement step comprising placing a multilayer nitride layer containing aluminum gallium nitride (Al x Ga 1-x N) on the above thick film layer; The above-mentioned thick film layer comprises single-crystal aluminum nitride, and a second intaglio pattern is formed on the lower surface to prevent crack formation caused by differences in lattice constants and thermal expansion coefficients of the substrate layer and the thick film layer, respectively. A method for manufacturing a nitride semiconductor device, wherein the second intaglio pattern is placed on (x, y) coordinates corresponding to the first intaglio pattern when the z-axis is an axis perpendicular to the ground.
In claim 1, The above substrate layer comprises a non-etching layer; and an etching layer disposed on the non-etching layer and including the first intaglio pattern. The above substrate preparation step is, (111) A silicon preparation step for preparing a silicon substrate including silicon having a crystal plane of orientation; and A method for manufacturing a nitride semiconductor device, further comprising a detailed step of a pattern forming step of etching the upper surface of the silicon substrate to form the etched layer.
In claim 1, The above nitride batching step is, A channel placement step of placing a channel layer comprising aluminum gallium nitride (Al x Ga 1-x N) on the above thick film layer; and The method further includes a detailed step of a barrier placement step of placing a barrier layer comprising aluminum gallium nitride (Al x Ga 1-x N) on the channel layer, and The aluminum gallium nitride (Al x Ga 1-x N) included in each of the above channel layer and barrier layer has different x values, and The method for manufacturing the above-mentioned nitride semiconductor device is, A method for manufacturing a nitride semiconductor device, further comprising a substrate removal step for removing the substrate layer after the above nitride placement step is performed.
In claim 3, The method for manufacturing the above-mentioned nitride semiconductor device is, The method further includes a metal placement step of placing a metal layer on the lower surface of the thick film layer from which the substrate layer has been removed. A method for manufacturing a nitride semiconductor device, wherein the metal layer comprises a metal material and performs the role of a heat dissipation layer for the nitride semiconductor device.
A method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film, (111) A substrate preparation step comprising silicon having a crystalline plane of orientation and a substrate layer having a first intaglio pattern formed on its upper surface; A thick film placement step of placing a thick film layer formed by an epitaxial lateral overgrowth (ELO) method on the substrate layer; and A nitride placement step comprising placing a multilayer nitride layer containing aluminum gallium nitride (Al x Ga 1-x N) on the above thick film layer; The above-mentioned thick film layer comprises single-crystal aluminum nitride, and a second intaglio pattern is formed on the lower surface to prevent crack formation caused by differences in lattice constants and thermal expansion coefficients of the substrate layer and the thick film layer, respectively. The above nitride batching step is, n-layer placement step of placing an n-layer doped with n-type on the above-mentioned thick film layer; A true layer placement step of placing a true layer on the above n-layer; and The method further includes a detailed step of a p-layer placement step of placing a p-layer doped with p-type on the intrinsic layer above, and Each of the above n-layer, intrinsic layer, and p-layer comprises either aluminum gallium nitride (Al x Ga 1-x N) and gallium nitride (GaN), and The method for manufacturing the above-mentioned nitride semiconductor device is, A method for manufacturing a nitride semiconductor device, further comprising a substrate removal step for removing the substrate layer after the above nitride placement step is performed.
In claim 5, The method for manufacturing the above-mentioned nitride semiconductor device is, The method further includes a lower electrode placement step of placing a lower electrode layer on the lower surface of the thick film layer from which the substrate layer has been removed. A method for manufacturing a nitride semiconductor device, wherein the lower electrode layer comprises a metallic material and forms an n-type ohmic contact when in contact with the n layer.
A method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film, (111) A substrate preparation step comprising silicon having a crystalline plane of orientation and a substrate layer having a first intaglio pattern formed on its upper surface; A thick film placement step of placing a thick film layer formed by an epitaxial lateral overgrowth (ELO) method on the substrate layer; and A nitride placement step comprising placing a multilayer nitride layer containing aluminum gallium nitride (Al x Ga 1-x N) on the above thick film layer; The above-mentioned thick film layer comprises single-crystal aluminum nitride, and a second intaglio pattern is formed on the lower surface to prevent crack formation caused by differences in lattice constants and thermal expansion coefficients of the substrate layer and the thick film layer, respectively. In the case where a part of the above second intaglio pattern is formed to penetrate the above thick film layer in the vertical direction, A method for manufacturing a nitride semiconductor device in which a third intaglio pattern is formed on the lower surface of the nitride layer.
In claim 6, In the case where a part of the above second intaglio pattern is formed to penetrate the above thick film layer in the vertical direction, A method for manufacturing a nitride semiconductor device, wherein the nitride semiconductor device has a quasi-vertical PIN structure by partially contacting the lower electrode layer with the lower surface of the n layer.
In claim 1, The above first intaglio pattern is either a stripe pattern or a hole pattern, and A method for manufacturing a nitride semiconductor device, wherein the spacing between each pattern of the first intaglio pattern is 1 to 10 μm.
In claim 2, A method for manufacturing a nitride semiconductor device, wherein the thickness of the etching layer is 2 to 100 μm.
In claim 1, A method for manufacturing a nitride semiconductor device, wherein the thickness of the above-mentioned thick film layer is 3 μm or more.
In claim 1, The above second intaglio pattern includes a second etching region in which a portion of the lower surface of the thick film layer is etched in an upward direction, and A method for manufacturing a nitride semiconductor device, wherein the cross-sectional area of the second etching region decreases as it extends from the lower surface of the thick film layer toward the upper side.
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In claim 5, The method for manufacturing the above-mentioned nitride semiconductor device is, The method further includes an upper electrode placement step of placing an upper electrode layer in a portion of the upper surface of the above p-layer, and A method for manufacturing a nitride semiconductor device, wherein the upper electrode layer comprises a metallic material and forms a p-type ohmic contact when in contact with the p layer.
A nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate, (111) A substrate layer comprising silicon having a crystal plane of orientation and having a first intaglio pattern formed on its upper surface; and A thick film layer disposed on the above substrate layer and comprising single-crystal aluminum nitride; comprising A nitride layer disposed on the above-mentioned thick film layer and comprising aluminum gallium nitride (Al x Ga 1-x N) having a multilayer structure; and The above-mentioned thick film layer is formed by an epitaxial lateral overgrowth (ELO) method and includes a second intaglio pattern formed on the lower surface, thereby preventing crack formation caused by differences in lattice constants and coefficients of thermal expansion of the substrate layer and the thick film layer, respectively. A nitride semiconductor device in which, when the z-axis is an axis perpendicular to the ground, the second intaglio pattern is placed on (x, y) coordinates corresponding to the first intaglio pattern.
In claim 15, The above substrate layer is, non-etching layer; and A nitride semiconductor device comprising: an etching layer disposed on the above non-etching layer and including the first intaglio pattern.
In claim 15, The above nitride layer is, A channel layer disposed on the above-mentioned thick film layer and comprising aluminum gallium nitride (Al x Ga 1-x N); and A barrier layer disposed on the above channel layer and comprising aluminum gallium nitride (Al x Ga 1-x N); comprising A nitride semiconductor device in which aluminum gallium nitride (Al x Ga 1-x N) included in each of the channel layer and barrier layer has different x values.
A nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate, (111) A substrate layer comprising silicon having a crystal plane of orientation and having a first intaglio pattern formed on its upper surface; and A thick film layer disposed on the above substrate layer and comprising single-crystal aluminum nitride; comprising A nitride layer disposed on the above-mentioned thick film layer and comprising aluminum gallium nitride (Al x Ga 1-x N) having a multilayer structure; The above-mentioned thick film layer is formed by an epitaxial lateral overgrowth (ELO) method and includes a second intaglio pattern formed on the lower surface, thereby preventing crack formation caused by differences in lattice constants and coefficients of thermal expansion of the substrate layer and the thick film layer, respectively. The above nitride layer is, n-layer disposed on the above-mentioned thick film layer and doped with n-type; A true layer disposed on the above n-layer; and A p-layer disposed on the above intrinsic layer and doped with p-type; comprising A nitride semiconductor device in which each of the above n-layer, intrinsic layer, and p-layer comprises either aluminum gallium nitride (Al x Ga 1-x N) or gallium nitride (GaN).
In claim 17, The above nitride semiconductor device is, When the above substrate layer is removed, a metal layer disposed on the lower surface of the above thick film layer is further included, The above metal layer comprises a metal material and performs the role of a heat dissipation layer for the above nitride semiconductor device.
In claim 18, When the above substrate layer is removed, the nitride semiconductor device, A lower electrode layer disposed on the lower surface of the above-mentioned thick film layer; and It includes an upper electrode layer disposed in a portion of the upper surface of the p-layer and forming a p-type ohmic junction with the p-layer; Each of the above lower electrode layer and upper electrode layer comprises a metallic material, and A nitride semiconductor device in which the lower electrode layer forms an n-type ohmic contact when in contact with the n layer.

Description

A method of manufacturing a nitride semiconductor device including a single crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate. The present invention relates to a method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate and a single-crystal aluminum nitride thick film, and more specifically, to a method for manufacturing a nitride semiconductor device comprising a single-crystal aluminum nitride (AlN) thick film formed on a silicon (Si) substrate by an epitaxial lateral overgrowth (ELO) method by depositing a single-crystal aluminum nitride (AlN) thick film on a silicon substrate having an intaglio pattern formed thereon, thereby preventing crack formation due to differences in lattice constant and coefficient of thermal expansion and improving heat dissipation performance. A conventional nitride semiconductor device has a structure in which a single-crystal nitride layer containing gallium nitride (GaN) or aluminum gallium nitride (AlGaN) is grown on an aluminum nitride (AlN) buffer layer formed on a silicon substrate of the (111) plane. Generally, in order to grow a high-quality single crystal through heterogeneous growth, the crystallinity of the buffer layer must be high. However, conventional aluminum nitride buffer layers are prone to defects due to differences in lattice constants and thermal expansion coefficients with the silicon substrate, resulting in poor crystallinity and limitations in growing beyond a certain thickness. Consequently, there is a problem in that it is difficult to grow high-quality nitride layers. Accordingly, a method was proposed to improve the crystallinity of the nitride layer by further forming a transition layer containing gallium nitride (GaN) and gallium aluminum nitride (AlGaN) between the buffer layer and the nitride layer. However, since the transition layer has lower thermal conductivity than the buffer layer, it hinders the release of heat generated from the nitride layer during device operation, thereby degrading the heat dissipation performance of the device. In other words, there is a need for a manufacturing method that can improve the crystallinity of the buffer layer to enable the formation of a high-quality nitride layer without a transition layer, and to manufacture a nitride semiconductor device with improved heat dissipation performance. FIG. 1 illustrates a schematic diagram of a nitride semiconductor device according to one embodiment of the present invention. FIG. 2 schematically illustrates the manufacturing steps of a nitride semiconductor device according to one embodiment of the present invention. FIG. 3 schematically illustrates the detailed steps of the substrate preparation step according to one embodiment of the present invention. FIG. 4 schematically illustrates a first intaglio pattern of a substrate layer according to one embodiment of the present invention. FIG. 5 schematically illustrates the SEM measurement results of a first intaglio pattern of a substrate layer according to one embodiment of the present invention. FIG. 6 schematically illustrates a second intaglio pattern according to one embodiment of the present invention. FIG. 7 schematically illustrates the SEM measurement results of a second intaglio pattern according to one embodiment of the present invention. FIG. 8 schematically illustrates the SEM measurement results of a nitride semiconductor device according to one embodiment of the present invention. FIG. 9 schematically illustrates the manufacturing steps of Example 1 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 10 schematically illustrates the detailed steps of the nitride placement step of Example 1 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 11 schematically illustrates a vertical cross-sectional view according to each manufacturing step of Example 1 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 12 schematically illustrates Example 1 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 13 schematically illustrates the manufacturing steps of Example 2 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 14 schematically illustrates the detailed steps of the nitride placement step of Example 2 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 15 schematically illustrates a vertical cross-sectional view according to each manufacturing step of Example 2 of a nitride semiconductor device according to one embodiment of the present invention. FIG. 16 schematically illustrates Example 2 of a nitride semiconductor device according to one embodiment of the present invention. Hereinafter, various embodiments and/or aspects are disclosed with referenc