Method for manufacturing electronic device and electronic device

Abstract

To provide a method for manufacturing an electronic device which can suppress the generation of a defect, and an electronic device.SOLUTION: The method for manufacturing an electronic device according to an embodiment includes the step of forming a recess in a first surface side of a substrate. The substrate has a first surface and a second surface opposite to the first surface. The method includes the step of forming a protective film inside the recess. An end portion of the protective film covers the bottom surface of the recess. The height from the bottom surface of the protective film is lower than the first surface. The method includes the step of processing the substrate from the second surface side. The step of processing the substrate from the second surface side forms a through hole in the substrate from at least a part of the recess by exposing an end portion of the protective film. An opening on the side opposite to the first surface of the through hole is closed by the protective film. The method further includes the step of removing the protective film provided inside the through hole.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to a method for manufacturing an electronic device and an electronic device. [Background technology]

[0002] There are electronic devices that include a substrate with through holes. For example, an electron beam passes through the through holes. In such electronic devices, it is desirable to suppress the occurrence of defects. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-068505 Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiments of the present invention provide a method for manufacturing an electronic device that can suppress the occurrence of defects, and an electronic device. [Means for solving the problem]

[0005] According to an embodiment of the present invention, a method for manufacturing an electronic device includes a step of forming a recess on the first surface side of a substrate. The substrate has a first surface and a second surface opposite to the first surface. The manufacturing method includes a step of forming a protective film inside the recess. An end of the protective film covers a bottom surface of the recess. A height of the protective film from the bottom surface is lower than that of the first surface. The manufacturing method includes a step of processing the substrate from the second surface side. The step of processing the substrate from the second surface side exposes the end of the protective film, thereby forming a through hole in the substrate from at least a part of the recess. An opening of the through hole on the side opposite to the first surface is blocked by the protective film. The manufacturing method includes a step of removing the protective film provided in the through hole. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic cross-sectional view illustrating an electronic device according to an embodiment. [Figure 2] FIG. 2 is a schematic plan view illustrating the electronic device according to the embodiment. [Figure 3] 3(a) to 3(f) are schematic cross-sectional views illustrating the method for manufacturing the electronic device according to the embodiment. [Figure 4] 4(a) to 4(e) are schematic cross-sectional views illustrating a method for manufacturing an electronic device according to the embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. [Figure 7] FIG. 7 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. [Figure 8] FIG. 8 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. [Figure 9] FIG. 9 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate.

[0008] FIG. 1 is a schematic cross-sectional view illustrating an electronic device according to an embodiment. FIG. 2 is a schematic plan view illustrating the electronic device according to the embodiment. Fig. 1 shows a cross section of an electronic device 101 according to an embodiment. As shown in Fig. 1, the electronic device 101 has a substrate 10 and an electrode 20. For example, a first electrode 21 and a second electrode 22 are provided as a pair of electrodes 20. Fig. 2 is a plan view of the substrate 10 and the electrode 20 as viewed along the arrow AR1 shown in Fig. 1. For convenience, elements other than the substrate 10 and the electrode 20 are appropriately omitted from Fig. 2. Fig. 1 corresponds to a cross section taken along line AA shown in Fig. 2.

[0009] 1, the substrate 10 has a first surface 10a and a second surface 10b opposite to the first surface 10a. The first surface 10a is, for example, the main surface of the substrate 10.

[0010] In the description of the embodiment, the direction from the second surface 10b to the first surface 10a is referred to as the Z direction (first direction). The Z direction is, for example, the thickness direction of the substrate 10. The direction perpendicular to the Z direction is referred to as the X direction (second direction), and the direction perpendicular to the Z direction and the X direction is referred to as the Y direction. The first surface 10a and the second surface 10b are, for example, surfaces extending along an XY plane perpendicular to the Z direction.

[0011] The substrate 10 has a through-hole 16. The through-hole 16 extends in the Z direction from the first surface 10a to the second surface 10b and penetrates the substrate 10. The through-hole 16 connects an opening 17a located on the first surface 10a with an opening 17b located on the second surface 10b.

[0012] The electrode 20 is provided in the through hole 16 and extends in the Z direction. The electrode 20 is provided along the inner surface of the through hole 16 and extends in the Z direction, and includes a plate-like portion that extends in, for example, the Y direction. The pair of electrodes 20 (first electrode 21 and second electrode 22) are arranged to face each other across the center Cx of the through hole 16. The center Cx is the center of the through hole 16 in the XY plane, in other words, the central axis extending in the Z direction.

[0013] The electrode 20 is, for example, hollow, i.e., the electrode 20 includes, for example, a cavity 23 inside the electrode 20.

[0014] The electronic device 101 is used, for example, to control an electron beam passing through the through-hole 16. The electronic device 101 controls the direction of the electron beam passing between the pair of electrodes 20 and through the through-hole 16, for example, by controlling the magnitude of the voltage applied between the pair of electrodes 20. The electronic device 101 is applied to devices that control an electron beam to irradiate an object and perform observation, processing, etc., such as an electron microscope that observes surfaces with an electron beam, an electron beam lithography device that draws fine patterns on a mask or wafer, or an inspection device that scans a surface with an electron beam to detect defects. The electronic device 101 is, for example, an electron beam control device such as an electrostatic lens or a deflector.

[0015] However, the applications of the electronic device according to the embodiment are not limited to the above. The embodiment can be applied to any device having a through-hole formed in a substrate. For example, the embodiment can be applied to any device in which electrodes are appropriately provided in the through-hole as needed. The number of electrodes provided in the through-hole 16 is not limited to two, but may be one, or three or more.

[0016] The substrate 10 has a first portion 11 and a second portion 12. In this example, the substrate 10 further has a third portion 13.

[0017] The first portion 11 includes a portion (hole portion 16a) of the through hole 16. The first portion 11 is a portion that includes the second surface 10b of the substrate 10. The first portion 11 forms an opening 17b of the through hole 16 on the second surface 10b side. The first portion 11 determines the diameter of the portion (hole portion 16a) of the through hole 16 between the first surface 10a and the second surface 10b. The diameter is, for example, the length along the X direction. The size of the diameter of the through hole corresponds to, for example, the size of the cross-sectional area of ​​the through hole.

[0018] In this example, the diameter d16a of the through hole in the first portion 11 (the diameter of the hole 16a) increases as it approaches the opening 17b in the Z direction. For example, the inner surface 18a of the through hole 16 in the first portion 11 (the inner surface of the hole 16a) is an inclined surface inclined with respect to the Z direction. For example, the entire inner surface 18a is inclined so as to move away from the center Cx as it approaches the opening 17b in the Z direction. For example, in the first portion 11, the through hole 16 increases isotropically in the XY plane as it approaches the opening 17b in the Z direction.

[0019] Thus, in this example, the inner surface 18a is an inclined surface, and the diameter d16a increases continuously as it approaches the opening 17b in the Z direction. However, this is not limiting, and in an embodiment, for example, the inner surface 18a may be provided with one or more steps, and the diameter d16a may increase stepwise as it approaches the opening 17b in the Z direction.

[0020] The second portion 12 is located between the first portion 11 and the first surface 10a, and includes another part (hole portion 16b) of the through hole 16. The second portion 12 is a portion that includes the first surface 10a of the substrate 10. The second portion 12 forms an opening 17a on the first surface 10a side of the through hole 16. The second portion 12 determines the diameter of the part (hole portion 16b) of the through hole 16 between the first portion 11 and the first surface 10a.

[0021] The electrode 20 is disposed in the second portion 12 within the through-hole 16. That is, the electrode 20 is disposed within the hole portion 16b. In other words, the second portion 12 is the portion of the substrate 10 where the electrode 20 is disposed. The electrode 20 is located closer to the first surface 10a in the Z direction than the first portion 11 and the third portion 13. The electrode 20 is not provided on the first portion 11 or the third portion 13.

[0022] The inner surface 18b of the through hole 16 in the second portion 12 (the inner surface of the hole 16b) extends, for example, along the Z direction. The inner surface 18b may include a portion that extends substantially parallel to the Z direction. In this example, the diameter d17b of the opening 17b is larger than the diameter d16b of the through hole 16 in the second portion 12 (the diameter of the hole 16b).

[0023] The third portion 13 is located between the first portion 11 and the second portion 12 and includes another portion (hole portion 16c) of the through hole 16. The hole portion 16c is aligned with the hole portions 16a and 16c in the Z direction and connects the hole portions 16a and 16c. The third portion 13 defines the diameter of the portion (hole portion 16c) of the through hole 16 between the first portion 11 and the second portion 12.

[0024] For example, the diameter d16c of the through hole 16 in the third portion 13 (the diameter of the hole 16c) is smaller than the diameter d16b of the second portion 12. In this example, the inner surface 18c of the through hole 16 in the third portion 13 (the inner surface of the hole 16c) extends along the Z direction. The diameter d16c of the third portion 13 may be constant along the Z direction. For example, the diameter d16a of the first portion 11 is larger than the diameter d16c of the third portion 13.

[0025] The electronic device 101 further includes an insulating layer 41 and an insulating layer 42. The insulating layer 41 is located between the second portion 12 of the substrate 10 and the first electrode 21. The insulating layer 41 contacts the inner surface 18b of the through hole 16 in the second portion 12 and the side surface of the first electrode 21. The first electrode 21 is electrically insulated from the substrate 10 by the insulating layer 41. Similarly, the insulating layer 42 is located between the second portion 12 of the substrate 10 and the second electrode 22. The insulating layer 42 contacts the inner surface 18b of the through hole 16 in the second portion 12 and the side surface of the second electrode 22. The second electrode 22 is electrically insulated from the substrate 10 by the insulating layer 42. The insulating layers 41 and 42 may be formed as a single continuous insulating layer. The insulating layers 41 and 42 may be interlayer insulating films. That is, a wiring layer may be provided inside the insulating layers 41 and 42.

[0026] The electronic device 101 further includes, for example, a wiring layer 51, a wiring layer 52, a connection electrode 53, and a connection electrode 54. The wiring layer 51 is provided on the insulating layer 41 on the first surface 10a of the substrate 10. The wiring layer 52 is provided on the insulating layer 42 on the first surface 10a of the substrate 10. The wiring layer 51 is electrically connected to the first electrode 21 by, for example, contacting an end of the first electrode 21 on the first surface 10a side. The wiring layer 52 is electrically connected to the second electrode 22 by, for example, contacting an end of the second electrode 22 on the first surface 10a side. The connection electrode 53 is provided on the wiring layer 51 and electrically connected to the wiring layer 51. The connection electrode 54 is provided on the wiring layer 52 and electrically connected to the wiring layer 52.

[0027] The wiring layer 51, the wiring layer 52, the connection electrode 53, and the connection electrode 54 are used, for example, to electrically connect the electronic device 101 to another device. The connection electrode 53 and the connection electrode 54 are, in other words, electrode pads. For example, the voltage between the first electrode 21 and the second electrode 22 is set via the wiring layer 51, the wiring layer 52, the connection electrode 53, and the connection electrode 54. The voltage between the first electrode 21 and the second electrode 22 is set, for example, by another device connected via the connection electrode 53 and the connection electrode 54.

[0028] However, the method for setting the voltage between the first electrode 21 and the second electrode 22 is not limited to the above. For example, a control circuit for setting the voltage between the first electrode 21 and the second electrode 22 may be provided on the substrate 10. For example, if the substrate 10 is a semiconductor substrate, a CMOS circuit or the like may be provided on the substrate 10 in advance. A wiring layer connecting the control circuit and the electrode 20 may be provided, for example, inside the substrate 10. The wiring layer 51, the wiring layer 52, the connection electrode 53, and the connection electrode 54 may be provided as needed and may be omitted.

[0029] 2, in this example, the planar shape of through-hole 16 (the shape in the XY plane viewed along the Z direction) is octagonal. The planar shape of opening 17b (and the planar shape of hole 16a) is, for example, octagonal. However, this is not limiting, and the planar shape of through-hole 16 may be any shape, such as a rectangle or a circle.

[0030] As described above, in the first portion 11 (see FIG. 1) of the substrate 10, the through hole 16 expands, for example, isotropically. In this case, the planar shape of the opening 17b (and the planar shape of the hole 16a) is, for example, a shape similar to the planar shape of the hole 16c formed by the inner surface 18c of the through hole 16. Alternatively, the opening 17b (and the hole) has, for example, an octagonal planar shape that expands outward, reflecting the planar shape of the hole 16c formed by the inner surface 18c of the through hole 16. Note that the planar shape of the hole 16b (see FIG. 1) in the second portion 12 may be a shape different from the shape similar to the planar shape of the opening 17b.

[0031] 3(a) to 3(f) and 4(a) to 4(e) are schematic cross-sectional views illustrating the method for manufacturing the electronic device according to the embodiment. As shown in FIG. 3(a), a step of forming grooves 18 on the first surface 10a side of the substrate 10 is performed. The substrate 10 may be, for example, a silicon substrate. The grooves 18 are formed, for example, by lithography and etching. The width of the grooves 18 is, for example, about 2 μm (for example, 1 μm or more and 3 μm or less). The depth of the grooves 18 is, for example, 10 μm or more and 60 μm or less. As will be described later, electrodes are formed in the grooves 18. The electrodes are arranged, for example, in pairs. After the through holes are formed, an electron beam passes between the pair of electrodes.

[0032] As shown in FIG. 3(b), a step of forming an insulating film 40 inside the trench 18 is performed. The insulating film 40 is an insulating film that will become the above-mentioned insulating layer 41 and insulating layer 42 (see FIG. 1). More specifically, the insulating film 40 is formed on the entire surface of the first surface 10a side of the substrate 10, to form the insulating film 40 on the inner side surface of the trench 18. The insulating film 40 can be made of, for example, silicon oxide.

[0033] As shown in FIG. 3( c), a conductive film 20f that will become the electrode 20 is formed on the entire surface of the insulating film 40, and the conductive film 20f is formed inside the insulating film 40 within the groove 18. The conductive film 20f is formed, for example, by vapor deposition. The material of the conductive film 20f (the material of the electrode 20) is, for example, tungsten (W), gold (Au), copper (Cu), aluminum (Al), or titanium nitride (TiN). The conductive film 20f formed by vapor deposition may not fully fill the deep portion of the groove 18. This may result in the electrode 20 having a hollow structure. By adjusting the thickness of the conductive film 20f, the upper portion of the groove 18 is closed by the deposition of the conductive film 20f from both sides of the groove 18. The conductive film 20f may be formed by filling the groove 18 using CVD, or by vapor deposition such as ALD, plating, or sputtering.

[0034] 3(d), the conductive film 20f formed on the insulating film 40 outside the groove 18 is removed by etching. As a result, the electrode 20 embedded in the groove 18 is formed from the conductive film 20f. In this manner, the method for manufacturing an electronic device includes a step of forming the electrode 20 extending in the Z direction on the substrate 10. The step of forming the electrode 20 includes forming the electrode 20 inside the insulating film 40 in the groove 18.

[0035] As shown in FIG. 3( e), wiring layers 51 and 52 are formed to be electrically connected to the exposed upper portions of the electrodes 20. For example, a metal layer to be the wiring layers is formed on the insulating film 40 and on the electrodes 20, and the metal layer is patterned by lithography and etching. Note that the metal layer in the area where the through holes will be formed later is removed by etching. Furthermore, as necessary, connection electrodes 53 and 54 are formed on the wiring layers 51 and 52. The wiring layers 51, 52, connection electrodes 53, and connection electrodes 54 are made of a metal material such as Au.

[0036] Next, for example, a through hole is formed between the pair of electrodes 20. For example, the through hole is formed by processing the substrate 10 by resist patterning and etching. Before the through hole is formed, the thickness of the substrate 10 may be, for example, 700 μm or more. In this case, it may be difficult to form a through hole that penetrates the substrate 10 in a single process. Therefore, first, a recess that will become the through hole is formed from the first surface 10a side of the substrate 10. For example, a recess that is deeper than the final desired thickness of the substrate is formed in advance. Then, the through hole is formed by cutting the second surface 10b side of the substrate.

[0037] 3(f), a step of forming a recess 19 on the first surface 10a side of the substrate 10 is performed. In the step of forming the recess 19, the recess 19 is formed so as to be aligned with the electrode 20 and the insulating film 40 in a direction intersecting the Z direction. This exposes the insulating film 40 formed on the side surface of the electrode 20 embedded in the groove 18. The recess 19 is formed between the pair of grooves 18 by, for example, lithography and etching.

[0038] The recesses 19 are deeper than the grooves 18. In other words, in the Z direction, the bottom of the recesses 19 is between the bottom of the grooves 18 and the second surface 10b. The depth of the recesses 19 can be, for example, not less than 100 μm and not more than 200 μm (for example, about 155 μm).

[0039] Thereafter, as shown in FIG. 4(a), a step of exposing the electrode 20 in the recess 19 is performed. This step includes removing a portion of the insulating film 40 shown in FIG. 3(f). For example, by etching using an etchant containing fluorine, the range of the insulating film 40 shown in FIG. 3(f) including the portion exposed in the recess 19 is removed. For example, an oxide film is etched using HF gas or the like. As a result, the entire side surface of the electrode 20 facing the recess 19 is exposed in the recess 19. As a result, insulating layers 41 and 42 are formed from the insulating film 40. The side surfaces of the pair of electrodes 20 face each other across the recess 19.

[0040] 4(b), a step of forming a protective film 30 inside the recess 19 is performed. The protective film 30 is formed by applying an organic material such as resist or polyimide, for example.

[0041] The end of the protective film 30 on the second surface 10b side covers the bottom surface 19b of the recess 19. For example, the entire bottom surface 19b of the recess 19 is in contact with the end of the protective film 30. A portion of the side surface 19s of the recess is in contact with the protective film 30. The height of the protective film 30 from the bottom surface 19b is lower than the first surface 10a of the substrate 10. In other words, the protective film 30 does not completely fill the recess 19. In the Z direction, the upper end 30a of the protective film 30 (the end on the first surface 10a side in the X direction) is between the first surface 10a and the bottom surface 19b. The protective film 30 does not necessarily have to be formed on the exposed side surface of the electrode 20. Within the recess 19, a space may be formed above the protective film 30 (towards the first surface 10a). The portion of the electrode 20 above the protective film 30 is in contact with the space within the recess 19.

[0042] Thereafter, as shown in FIG. 4(c), a process is performed in which the substrate 10 is processed from the second surface 10b side. For example, the substrate 10 is thinned to a desired thickness by etching or cutting from the second surface 10b side. The desired thickness of the substrate 10 is, for example, approximately 100 μm or more and 500 μm or less. For example, if the depth of the recess 19 is 155 μm, the thickness of the substrate 10 is set to approximately 150 μm. This exposes the protective film 30 that was provided in the recess 19 on the second surface 10b side of the substrate 10. By exposing the end of the protective film 30 that covered the bottom surface 19b of the recess 19, a through hole 16 is formed from at least a portion of the recess 19. In this way, for example, a portion of the recess 19 and a portion of the groove 18 (see FIG. 3(a)) become the through hole 16.

[0043] 4(c), when the substrate 10 is thinned, the through-hole 16 is covered with the protective film 30. That is, the opening 17b of the through-hole 16 on the side opposite to the first surface 10a is closed by the protective film 30.

[0044] 4(c), an adhesive 31 may be provided on the first surface 10a side of the substrate 10, and a support (such as a support substrate) (not shown) may be attached to the substrate 10 using this adhesive 31. The adhesive 31 may be formed simultaneously with the protective film 30. The adhesive 31 may not be provided in the recess 19, and may not be in contact with the electrode 20. The first surface 10a side of the substrate 10 may be supported by adhesive tape or the like.

[0045] When processing the substrate 10, foreign matter may enter the through-hole 16. For example, when thinning the substrate 10 by cutting, scraps 10p (foreign matter, dust) of the substrate 10 are generated. Because the protective film 30 blocks the through-hole 16, the entry of foreign matter into the through-hole 16 can be suppressed.

[0046] In this example, after the step of processing the substrate 10 from the second surface 10b side and before the step of removing the protective film 30, a step of etching the second surface 10b side of the substrate 10 is performed as shown in FIG. 4(d). For the etching, for example, dry etching or isotropic etching is used. Debris 10p generated during the thinning of the substrate 10 can be removed from the front surface side (second surface 10b side) of the substrate 10 by the etching process and cleaning process.

[0047] During this etching, the thickness of the substrate 10 becomes slightly thinner. At the same time, for example, etching gas enters the boundary between the protective film 30 and the substrate 10. Of the inner surface of the through hole 16, the region on the second surface 10b side that was in contact with the protective film 30 is removed. As a result, the diameter (cross-sectional area) of the through hole 16 on the second surface 10b side becomes larger after the protective film 30 is removed.

[0048] Thereafter, as shown in FIG. 4(e), a step of removing the protective film 30 provided in the through-hole 16 is performed. For example, the organic material of the protective film 30 is removed by a solvent or ashing. By removing the protective film 30, the first surface 10a side and the second surface 10b side are connected via the through-hole 16. Note that the protective film 30 is not limited to organic materials such as resist or polyimide, and any material that can be removed after the through-hole 16 is formed can be used as appropriate. In this manner, the electronic device 101 according to the embodiment can be manufactured.

[0049] If foreign matter (e.g., debris generated when cutting the substrate) adheres inside the through-hole of the substrate, defects in the electronic device may occur. For example, the yield of the electronic device may decrease. In contrast, in the embodiment, the protective film 30 is provided, which can prevent foreign matter from entering the through-hole 16 through the opening 17b of the through-hole 16. This can prevent, for example, defects from occurring. For example, as shown in FIG. 4(a), the electrode 20 is exposed in the recess 19. According to the embodiment, it is possible to prevent foreign matter from adhering to the exposed electrode 20.

[0050] 4(d), foreign matter can be removed by etching the back surface of the substrate 10. Furthermore, since the protective film 30 is provided during this etching, the electrodes 20 exposed in the through holes 16 can be prevented from being damaged by the etching. This can further prevent, for example, defects from occurring.

[0051] For example, as shown in FIG. 4( b), the protective film 30 has an outer portion 33 located outside the recess 19 and an inner portion 34 located closer to the recess 19 than the outer portion 33. The inner portion 34 is located at the center of the recess 19 in the XY plane. The outer portion 33 is in contact with the side surface 19s of the recess 19. The outer portion 33 is located between the side surface 19s of the recess 19 and the inner portion 34 in the XY plane. In this example, the outer portion 33 is thicker than the inner portion 34. In other words, the length of the outer portion 33 along the Z direction is longer than the length of the inner portion 34 along the Z direction. By forming the protective film 30 thick, even if the side surface of the protective film 30 is exposed by the etching process described with reference to FIG. 4( d), the protective film 30 blocks the opening of the through hole 16, thereby further preventing foreign matter from entering the through hole 16.

[0052] For example, when forming a through-hole in the substrate 10, a recess is formed on the front side of the substrate 10, and then the back side of the substrate 10 is processed, another support substrate may be attached to the front side of the substrate 10. In this case, there is a reference example method in which the recess formed on the front side of the substrate 10 is filled with an organic material (adhesive). In this reference example method, for example, an organic material is applied to the front side of the substrate 10, and a support substrate made of a glass material is attached by baking. Then, the substrate 10 is inverted so that the support substrate is facing downward, and the upper side (the back side of the substrate) is etched. In such a reference example, the electrode exposed in the recess of the substrate 10 may be subjected to force from the organic material filled in the recess, resulting in deformation or breakage. For example, the organic material shrinks during application and curing of the organic material. This applies stress to the side surfaces and corners of the electrode that are in contact with the organic material, causing distortion. This may result in deformation or breakage of the electrode. In particular, when the electrode 20 is hollow, deformation or breakage may be more likely to occur.

[0053] In contrast, as described with reference to FIG. 4(b), the height of the protective film 30 from the bottom surface 19b of the recess 19 is lower than the first surface 10a. That is, the recess 19 is not completely filled with the protective film 30. This can prevent contact between the electrode 20 and the protective film 30. It can also prevent the electrode 20 from receiving force from the protective film 30. For example, deformation or breakage of the electrode 20 can be prevented, and the occurrence of defects can be further prevented. For example, even if the electrode 20 is hollow, the occurrence of defects can be prevented.

[0054] The protective film 30 does not need to come into contact with the electrode 20. The recess 19 is deeper than the groove 18 and deeper than the end of the electrode 20 on the second surface 10b side. The depth of the recess 19 can prevent the protective film 30 provided on the bottom of the recess 19 from coming into contact with the electrode 20. For example, the protective film 30 is below the electrode 20. That is, the position of the protective film 30 in the Z direction is between the position of the electrode 20 in the Z direction and the position of the second surface 10b in the Z direction. This prevents the protective film 30 from coming into contact with the electrode 20, for example, and can further prevent defects from occurring.

[0055] FIG. 5 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. As shown in Fig. 5, in this example, the electronic device 101 is stacked on a control board 200 including a control circuit CC. The control circuit CC includes, for example, a CMOS circuit and is an LSI (Large Scale Integration) formed within the control board 200. Note that, for convenience, Fig. 5 shows the control circuit CC in a simplified manner. The electronic device 101 may include the control board 200 (control circuit CC).

[0056] The pair of electrodes 20 are connected to a control circuit CC via connection electrodes 53 and 54. The control circuit CC controls the voltage between the pair of electrodes 20 to control the direction in which the electron beam passes through the through hole 16 from the first surface 10a side toward the second surface 10b side.

[0057] 5 is an example of an electron beam when the control circuit CC does not apply a voltage between the pair of electrodes 20. The line Bon is an example of an electron beam when the control circuit CC applies a voltage between the pair of electrodes 20. In this way, the electron beam that has passed through the through-hole provided in the control board 200 travels from between the pair of electrodes 20 provided in the second portion 12 of the board 10 to the first portion 11 and passes through the through-hole 16.

[0058] For example, the control circuit CC sets one of the pair of electrodes 20 to ground and controls the voltage of the other. Alternatively, the control circuit CC may control the potentials of both electrodes 20. There may be two or more pairs of electrodes 20. The control circuit CC may be provided on the substrate 10.

[0059] As described above with reference to FIG. 4(d), for example, in the manufacture of the electronic device 101, a step of etching the second surface 10b side of the substrate 10 is performed. In this step, as shown in FIG. 5, the diameter of the through hole 16 in the first portion 11 of the substrate 10 increases in the Z direction as it approaches the opening 17b. For example, this etching step increases the diameter of the through hole 16 in the first portion 11 isotropically in the XY plane. According to the embodiment, the diameter of the opening 17b can be increased, and the direction of the electron beam can be significantly changed, for example, as shown by the line Bon in FIG. 5.

[0060] In this way, by etching the second surface 10b side of the substrate 10, it is possible to form a large cross-sectional area of ​​the through-hole 16 after removing the protective film 30. Therefore, even if the deflection angle of the electron beam is increased by the electric field generated by the electrode 20, for example, the electron beam does not interfere with the substrate 10. For example, it is possible to suppress defects caused by unintentional interference between the electron beam and the substrate 10.

[0061] 1, for example, the diameter of the opening 17b is larger than the diameter of the through hole 16 in the second portion 12. For example, the diameter of the opening 17b is larger than the diameter of the through hole 16 in the third portion 13. Furthermore, for example, the inner surface 18a of the through hole 16 in the first portion 11 is an inclined surface inclined with respect to the Z direction. With this configuration, for example, interference of the electron beam with the substrate 10 is further suppressed.

[0062] FIG. 6 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. As shown in FIG. 6, in the electronic device 102 according to the embodiment, the through-hole 16 has a shape that widens toward the opening 17b over substantially the entire area below the electrode 20.

[0063] In this example, the entire inner surface 18a of the through-hole 16 in the first portion 11 of the substrate 10 is a slope that slopes outward from the through-hole 16 as it approaches the opening 17b. An upper end 18t of the sloped inner surface 18a (the end on the first surface 10a side in the Z direction) is located directly below the electrode 20, for example. The surface that continues directly from the upper end 18t of the inner surface 18a does not have to extend along the Z direction. For example, the substrate 10 does not need to have the third portion 13 described with reference to FIG. 1 , and the first portion 11 may continue directly from below the second portion 12.

[0064] The electronic device 102 can be manufactured in the same manner as the manufacturing method described above by adjusting the amount of etching described with reference to Fig. 4(d). The electronic device 102 can also prevent foreign matter from entering the through-hole 16 and prevent deformation or breakage of the electrode 20. By widening the through-hole 16 in the first portion 11 toward the opening 17b, it is possible to prevent interference between, for example, a deflected electron beam and the substrate 10.

[0065] FIG. 7 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. 7, in the electronic device 103 according to the embodiment, the through-hole 16 has a shape that narrows midway below the electrode 20. The inner surface 18c of the third portion 13 of the substrate 10 is an inclined surface that is inclined with respect to the Z direction.

[0066] In this example, the inner surface 18c of the third portion 13 is inclined toward the center Cx of the through hole 16 as it approaches the opening 17b in the Z direction. The diameter of the through hole 16 in the third portion 13 decreases as it approaches the opening 17b in the Z direction. The diameter d17b of the opening 17b may be smaller than the diameter d16b of the through hole 16 in the second portion 12. The diameter d17b of the opening 17b may be smaller than the diameter d16c of the through hole 16 in the upper part of the third portion 13.

[0067] The electronic device 103 can be manufactured in the same manner as the manufacturing method described above by adjusting the etching conditions described with reference to FIG. 3(f) to make the side surfaces of the recesses 19 inclined. When the recesses 19 have inclined surfaces, for example, the recesses 19 can be easily formed. In the electronic device 103, it is possible to prevent foreign matter from entering the through holes 16 and to prevent deformation and breakage of the electrodes 20. Furthermore, by widening the through holes 16 in the first portion 11 toward the openings 17b, it is possible to prevent interference between a deflected electron beam and the substrate 10, for example.

[0068] FIG. 8 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. 8, in the electronic device 104 according to the embodiment, the through-hole 16 has a shape extending along the Z direction. That is, the inner surface 18a of the first portion 11 of the substrate 10 extends along the Z direction. The inner surface 18a may be parallel to the Z direction.

[0069] The electronic device 104 can be manufactured in the same manner as the manufacturing method described above by omitting the etching step described with reference to Fig. 4(d). For example, an increase in the number of steps can be suppressed. In the electronic device 104, it is also possible to suppress the intrusion of foreign matter into the through-holes 16 and the deformation and breakage of the electrodes 20.

[0070] FIG. 9 is a schematic cross-sectional view illustrating the electronic device according to the embodiment. 9, in an electronic device 105 according to the embodiment, a substrate 10 has a plurality of through holes 16. The electronic device 105 has a plurality of electrodes 20 (a plurality of first electrodes 21 and a plurality of second electrodes 22) provided in the plurality of through holes 16, respectively.

[0071] The electronic device may have any number of through holes 16. The number of through holes 16 provided in the electronic device may be set appropriately depending on, for example, the application of the electronic device.

[0072] The embodiment may include the following configurations (for example, technical solutions). (Configuration 1) a step of forming a recess on a first surface side of a substrate having a first surface and a second surface opposite to the first surface; forming a protective film inside the recess, the protective film having an edge covering a bottom surface of the recess and a height from the bottom surface lower than the first surface; a step of processing the substrate from the second surface side, exposing the end portion of the protective film to form a through hole in the substrate from at least a part of the recess, the opening of which is on the opposite side to the first surface and is blocked by the protective film; removing the protective film provided in the through hole; A method for manufacturing an electronic device, comprising: (Configuration 2) 2. The manufacturing method according to configuration 1, further comprising the step of etching the second surface side of the substrate after the step of processing the substrate from the second surface side and before the step of removing the protective film. (Configuration 3) The method further includes forming an electrode on the substrate, the electrode extending along a first direction from the second surface toward the first surface, 3. The method of claim 1, wherein the electrode is exposed within the recess. (Configuration 4) 4. The manufacturing method according to configuration 3, wherein the recess is deeper than the end of the electrode on the second surface side. (Configuration 5) 5. The method of claim 3 or 4, wherein the electrode is hollow. (Configuration 6) forming a groove on the first surface side of the substrate; forming an insulating film inside the trench; Furthermore, 6. The manufacturing method according to any one of configurations 3 to 5, wherein the step of forming the electrode forms the electrode inside the insulating film in the trench. (Configuration 7) after the step of forming the recess, a step of exposing the electrode in the recess, the step of forming the recess includes forming the recess so as to be aligned with the electrode provided in the groove in a second direction intersecting the first direction; 7. The method of claim 6, wherein the step of exposing the electrode includes removing a portion of the insulating film. (Configuration 8) 8. The method according to any one of aspects 3 to 7, wherein the protective film is not in contact with the electrode. (Configuration 9) 9. The manufacturing method according to any one of configurations 3 to 8, wherein the position of the protective film in the first direction is between the position of the electrode in the first direction and the position of the second surface in the first direction. (Configuration 10) the substrate after the through hole is formed has a first portion that forms the opening on the side opposite to the first surface of the through hole; The manufacturing method according to configuration 2, wherein the step of etching the second surface side of the substrate increases the diameter of the through hole in the first portion as it approaches the opening in a first direction from the second surface to the first surface. (Configuration 11) 11. The manufacturing method according to claim 10, wherein the step of etching the second surface side of the substrate increases the diameter of the through hole in the first portion isotropically in a plane perpendicular to the first direction. (Configuration 12) the protective film has an outer portion in contact with a side surface of the recessed portion and an inner portion located more inward of the recessed portion than the outer portion, The manufacturing method according to any one of the first to eleventh aspects, wherein the length of the outer portion along a first direction from the second surface to the first surface is longer than the length of the inner portion along the first direction. (Configuration 13) a substrate having a first surface and a second surface opposite to the first surface, the substrate having a through hole extending along a first direction from the second surface toward the first surface; an electrode provided in the through hole and extending along the first direction; Equipped with The substrate is a first portion including an opening of the through hole on the second surface side; a second portion located between the first portion and the first surface and including a part of the through hole; and the electrode is disposed in the second portion within the through hole and is located closer to the first surface than the first portion; The diameter of the through hole in the first portion increases as it approaches the opening in the first direction. (Configuration 14) 14. The electronic device according to claim 13, wherein the diameter of the opening is larger than the diameter of the through hole in the second portion. (Configuration 15) The electronic device of configuration 13 or 14, wherein the inner surface of the through hole in the first portion is an inclined surface inclined with respect to the first direction. (Configuration 16) the substrate has a third portion located between the first portion and the second portion and including another part of the through hole; 16. The electronic device according to any one of configurations 13 to 15, wherein the diameter of the through hole in the third portion is smaller than the diameter of the through hole in the second portion. (Configuration 17) 17. The electronic device of claim 16, wherein the inner surface of the through hole in the third portion extends along the first direction. (Configuration 18) an inner surface of the through hole in the third portion is an inclined surface inclined with respect to the first direction, 17. The electronic device according to claim 16, wherein the diameter of the through hole in the third portion decreases toward the opening in the first direction. (Configuration 19) A plurality of the electrodes is provided, the substrate has a plurality of the through holes, 19. The electronic device according to any one of configurations 13 to 18, wherein the plurality of electrodes are provided in the plurality of through holes, respectively. (Configuration 20) a pair of the electrodes facing each other across a center of the through hole in a plane perpendicular to the first direction, The pair of electrodes is electrically connected to a control circuit, The electronic device described in any one of configurations 13 to 19, wherein the control circuit controls the voltage between the pair of electrodes to control the direction in which the electron beam passes through the through hole from the first surface side toward the second surface side.

[0073] According to the embodiment, it is possible to provide a manufacturing method for an electronic device and an electronic device that can suppress the occurrence of defects.

[0074] In this specification, "electrically connected" includes not only connection through direct contact but also connection via other conductive members. In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

[0075] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element included in an electronic device is within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting from known ranges.

[0076] Any combination of two or more elements of each embodiment to the extent technically possible is also included within the scope of the present invention as long as it encompasses the gist of the present invention.

[0077] In addition, all electronic devices and manufacturing methods that can be implemented by a person skilled in the art by appropriately modifying the design based on the electronic device and manufacturing method described above as embodiments of the present invention also fall within the scope of the present invention, as long as they include the gist of the present invention.

[0078] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0079] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0080] 10: Circuit board 10a: 1st page 10b: 2nd side 10p: scraps 11~13: Parts 1~3 16:Through hole 16a, 16b, 16c: Hole 17a, 17b: Opening 18: Groove 18a, 18b, 18c: Inner surface 18t:Top end 19: Recess 19b: bottom 19s:Side 20: Electrode 20f: Conductive film 21: 1st electrode 22:Second electrode 23: Cavity 30:Protective film 30a: Upper end 31:Adhesive 33:Outer part 34: Inner part 40: insulating film 41, 42: Insulating layer 51, 52: Wiring layer 53, 54: Connection electrodes 101~105:Electronic equipment 200: Control board Boff, Bon: Line CC: Control circuit Cx: Center d16a, d16b, d16c, d17b: diameter

Claims

1. forming a recess on the first surface side of a substrate having a first surface and a second surface opposite to the first surface; forming a protective film inside the recess, the protective film having an edge covering a bottom surface of the recess and a height from the bottom surface lower than the first surface; a step of processing the substrate from the second surface side, exposing the end portion of the protective film to form a through hole in the substrate from at least a part of the recess, the opening of which is on the opposite side to the first surface and is blocked by the protective film; removing the protective film provided in the through hole; A method for manufacturing an electronic device, comprising:

2. The manufacturing method according to claim 1 , further comprising the step of etching the second surface side of the substrate after the step of processing the substrate from the second surface side and before the step of removing the protective film.

3. The method further includes forming an electrode on the substrate, the electrode extending along a first direction from the second surface toward the first surface, The manufacturing method according to claim 1 or 2, wherein the electrode is exposed in the recess.

4. The manufacturing method according to claim 3 , wherein the recess is deeper than an end of the electrode on the second surface side.

5. The method of claim 3 , wherein the electrode is hollow.

6. forming a groove on the first surface side of the substrate; forming an insulating film inside the trench; Furthermore, The manufacturing method according to claim 3 , wherein the step of forming the electrode comprises forming the electrode inside the insulating film in the trench.

7. after the step of forming the recess, a step of exposing the electrode in the recess, the step of forming the recess includes forming the recess so as to be aligned with the electrode provided in the groove in a second direction intersecting the first direction; The manufacturing method according to claim 6 , wherein the step of exposing the electrode includes removing a portion of the insulating film.

8. The manufacturing method according to claim 3 , wherein the protective film does not contact the electrode.

9. The manufacturing method according to claim 3 , wherein the position of the protective film in the first direction is between the position of the electrode in the first direction and the position of the second surface in the first direction.

10. the substrate after the through hole is formed has a first portion that forms the opening on the side opposite to the first surface of the through hole; 3. The manufacturing method according to claim 2, wherein the step of etching the second surface side of the substrate increases the diameter of the through hole in the first portion as it approaches the opening in a first direction from the second surface to the first surface.

11. The manufacturing method according to claim 10 , wherein the step of etching the second surface side of the substrate increases the diameter of the through hole in the first portion isotropically in a plane perpendicular to the first direction.

12. the protective film has an outer portion in contact with a side surface of the recessed portion and an inner portion located more inward of the recessed portion than the outer portion, The manufacturing method according to claim 1 or 2, wherein a length of the outer portion along a first direction from the second surface to the first surface is longer than a length of the inner portion along the first direction.

13. a substrate having a first surface and a second surface opposite to the first surface, the substrate having a through hole extending along a first direction from the second surface toward the first surface; an electrode provided in the through hole and extending along the first direction; Equipped with The substrate is a first portion including an opening of the through hole on the second surface side; a second portion located between the first portion and the first surface and including a part of the through hole; and the electrode is disposed in the second portion within the through hole and is located closer to the first surface than the first portion; An electronic device, wherein the diameter of the through hole in the first portion increases as it approaches the opening in the first direction.

14. The electronic device according to claim 13 , wherein a diameter of the opening is larger than a diameter of the through hole in the second portion.

15. The electronic device according to claim 13 , wherein an inner surface of the through hole in the first portion is an inclined surface inclined with respect to the first direction.

16. the substrate has a third portion located between the first portion and the second portion and including another part of the through hole; The electronic device according to claim 13 , wherein a diameter of the through hole in the third portion is smaller than a diameter of the through hole in the second portion.

17. The electronic device according to claim 16 , wherein an inner surface of the through-hole in the third portion extends along the first direction.

18. an inner surface of the through hole in the third portion is an inclined surface inclined with respect to the first direction, The electronic device according to claim 16 , wherein a diameter of the through hole in the third portion decreases toward the opening in the first direction.

19. A plurality of the electrodes is provided, the substrate has a plurality of the through holes, The electronic device according to claim 13 , wherein a plurality of the electrodes are provided in the plurality of through holes, respectively.

20. a pair of the electrodes facing each other across a center of the through hole in a plane perpendicular to the first direction, The pair of electrodes is electrically connected to a control circuit, 15. The electronic device according to claim 13, wherein the control circuit controls a voltage between the pair of electrodes to control a direction in which the electron beam passes through the through hole from the first surface side toward the second surface side.

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