X-ray inspection apparatus

Abstract

The present disclosure provides an X-ray inspection apparatus comprising: a manipulator; a handling unit for handling an object to be inspected to position same on the manipulator; an X-ray generator for irradiating the object being inspected on the manipulator with X-rays; and a detector for receiving the X-rays which have passed through the object being inspected, wherein the object to be inspected includes a high-bandwidth memory. The X-ray generator may comprise: a vacuum-forming unit in which the interior is selectively under vacuum; a high-voltage power supply unit connected to the vacuum-forming unit; a detachable unit detachably installed on the front end part of the vacuum-forming unit and having a target disposed on the front end thereof; and an electron gun unit for receiving power from the high-voltage power supply unit and emitting electrons toward the target.

Description

X-ray inspection device

[0001] The present disclosure relates to an X-ray inspection device.

[0002] The manufacturing yield of semiconductor DRAM is typically known to be 50–60%. In particular, for High Bandwidth Memory (HDM), data processing speed and capacity can be maximized by vertically stacking multiple DRAMs. Due to the nature of stacking multiple DRAMs in HDM, the yield of the process connecting the stacked DRAMs with silicon electrodes inevitably decreases. Therefore, an optimal inspection method is required to perform defect detection more effectively in response to the increasing stacking process.

[0003] An X-ray inspection device according to at least one embodiment of the present disclosure comprises: a manipulator; a handling unit for handling an object to be inspected and positioning it on the manipulator; an X-ray generator for irradiating an X-ray onto the object to be inspected positioned on the manipulator; and a detector for receiving the X-ray that has passed through the object to be inspected, wherein the object to be inspected includes a High Bandwidth Memory, and the X-ray generator may comprise: a vacuum forming unit in which the interior is selectively vacuum-formed; a high-voltage power supply unit connected to the vacuum forming unit; a detachable unit detachably installed at the tip of the vacuum forming unit and having a target at the tip; and an electron gun unit that receives power from the high-voltage power supply unit and emits electrons toward the target.

[0004] In addition, the X-ray inspection device may perform an inspection by placing at least one auxiliary means between the object to be inspected and the X-ray generator to prevent amplification of the leakage current when the leakage current generated on the semiconductor is exposed to the X-ray.

[0005] In addition, the X-ray generator has the above specifications, a tube voltage value of 40 to 160 kV, a maximum output value of 80 W, and a minimum X-ray focal spot value of 0.2 to 10 µm.

[0006] In addition, the electron gun unit can receive power from the high-voltage power supply and emit electrons toward the target in a pulsed manner.

[0007] Additionally, the at least one auxiliary means may include a collimator that controls the irradiation range of the X-ray irradiated onto the object to be inspected.

[0008] In addition, the collimator can be moved in position from the X-ray generator, and the X-ray generator can perform at least one of 2D inspection and 3D inspection of the object to be inspected through the collimator.

[0009] In addition, the at least one auxiliary means may include a filter capable of attenuating a specific energy range of the X-ray irradiated onto the object to be inspected.

[0010] In addition, the X-ray generator may allow the position of the electrons reaching the target to be shifted by placing a deflection means between the vacuum forming part and the target.

[0011] In addition, the X-ray generator may include a target adjustment unit capable of rotating the target according to a set time.

[0012] FIG. 1 is a drawing illustrating an X-ray inspection device according to at least one embodiment of the present disclosure.

[0013] FIG. 2 is a block diagram illustrating some of the components of an X-ray inspection device according to at least one embodiment of the present disclosure.

[0014] FIG. 3 is a drawing illustrating the state in which an X-ray inspection device according to at least one embodiment of the present disclosure inspects an object in a 2D manner.

[0015] FIG. 4 is a drawing illustrating the state in which an X-ray inspection device according to at least one embodiment of the present disclosure inspects an object in a 3D manner.

[0016] FIG. 5 is a diagram illustrating the state in which an X-ray inspection device according to at least one embodiment of the present disclosure selectively inspects a plurality of objects to be inspected.

[0017] FIG. 6 is a reference drawing showing the rate of reduction of refresh time related to a damage test on an object inspected by an X-ray inspection device according to at least one embodiment of the present disclosure.

[0018] FIG. 7 is a schematic cross-sectional view showing the configuration of an X-ray generator according to at least one embodiment of the present disclosure.

[0019] Figure 8 is an enlarged view showing the part indicated in Figure 7.

[0020] FIG. 9 is a schematic diagram illustrating pulsed X-ray irradiation of an X-ray generator according to the present disclosure.

[0021] FIG. 10 is a reference diagram comparing pulsed X-ray irradiation according to the present disclosure with X-ray irradiation by a general beam method.

[0022] FIG. 11 is a drawing showing the first receptacle illustrated in FIG. 7.

[0023] FIG. 12 is a schematic cross-sectional view showing an X-ray generator according to various embodiments of the present disclosure.

[0024] FIG. 13 is a schematic diagram showing another example of a connector portion between a high-voltage power supply unit and an electron gun unit according to various embodiments of the present disclosure.

[0025] Figure 14 is a drawing showing the exterior of an X-ray generator.

[0026] Figure 15 is a diagram showing the interior of an X-ray generator.

[0027] The following description, with reference to the attached drawings, is provided to facilitate a comprehensive understanding of various embodiments of the present disclosure as defined by the claims and their equivalents. While various specific details are included to aid understanding, they should be considered merely illustrative. Accordingly, those skilled in the art will recognize that various changes and modifications to the various embodiments described herein may be made without departing from the scope and spirit of the present disclosure. Additionally, for clarity and brevity, descriptions of well-known functions and configurations may be omitted.

[0028] The terms and words used in the following description and claims are not limited to their bibliographic meanings and have been used by the Discloser to enable a clear and consistent understanding of the present disclosure. Accordingly, it will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided merely for illustrative purposes and is not intended to limit the present disclosure as defined by the appended claims and their equivalents.

[0029] Terms such as "first," "second," etc., may be used to describe various components, but the components should not be limited by these terms. The terms may be used solely for the purpose of distinguishing one component from a component that follows. For example, without departing from the scope of the present disclosure, the first component may be named the second component, and similarly, the second component may be named the first component.

[0030] Unless otherwise defined, the terms used in the embodiments of the present disclosure may be interpreted in the sense commonly known to those skilled in the art. Additionally, terms such as 'front end', 'rear end', 'upper end', 'lower end', 'upper end', and 'lower end' used in the present disclosure are defined based on the drawings, and the shape and position of each component are not limited by these terms.

[0031] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the attached drawings.

[0032] FIG. 1 is a drawing illustrating an X-ray inspection device (100) according to at least one embodiment of the present disclosure. FIG. 2 is a block diagram illustrating some of the components of an X-ray inspection device (100) according to at least one embodiment of the present disclosure.

[0033] Referring to FIGS. 1 and 2, the X-ray inspection device (100) may include an X-ray generator (110), a handling unit (120), a detector (130), and a manipulator (140). The manipulator (140) may correspond to a configuration for holding an object to be inspected for X-ray inspection. When an object to be inspected is introduced into the X-ray inspection device (100), the handling unit (120) may move the object to a position for at least one of introduction, inspection, and discharge.

[0034] In addition, the X-ray generator (110) can irradiate the object to be inspected with X-rays when the handling unit (120) handles the object to be inspected and positions it on the manipulator (140). The detector (130) receives the X-rays passing through the object to be inspected, obtains inspection information regarding the object to be inspected, and outputs it.

[0035] Meanwhile, in the present disclosure, the object to be inspected may be a semiconductor, and in particular may include a High Bandwidth Memory. The X-ray inspection device (100) according to the present disclosure can reduce the occurrence of damage to the High Bandwidth Memory generated during the X-ray inspection by performing an inspection with a preset specification to prevent the amplification of the leakage current when the leakage current generated on the semiconductor is exposed to X-rays.

[0036] In addition, the X-ray generator (110) according to the present disclosure may have a maximum tube voltage value of approximately 40 to 160 kV as a specification for reducing damage to high-bandwidth memory caused by X-ray irradiation. The X-ray generator (110) may have a maximum output value of approximately 80 W and may have a minimum X-ray focal spot value of approximately 0.2 to 10 μm. Furthermore, the X-ray inspection device (100) of the present disclosure may have a resolution value of approximately 0.04 to 20 μm / pixel as a specification.

[0037] Additionally, the X-ray inspection device (100) according to the present disclosure may have a magnification of approximately 175.7 as a specification. The object to be inspected handled by the X-ray inspection device (100) according to the present disclosure is a semiconductor, and in particular, the through silicon via of the semiconductor may have a diameter value in the range of approximately 2 to 5 μm, for example. The microbump of the semiconductor may have a diameter value in the range of approximately 20 to 25 μm.

[0038] FIG. 3 is a diagram illustrating a state in which an object to be inspected is inspected in a 2D manner among the components of an X-ray inspection device (100) for reducing semiconductor inspection damage according to at least one embodiment of the present disclosure.

[0039] Referring to FIG. 3, the X-ray generator (110) according to the present disclosure may be positioned in a direction facing the object to be inspected (T) for a 2D inspection. The X-ray generator (110) irradiates X-rays (B) onto the object to be inspected (T) in a specific unidirectional direction, and the aforementioned detector (130) may be positioned to face the X-ray generator (110) with the object to be inspected in between, so as to receive the irradiated X-rays (B).

[0040] FIG. 4 is a diagram illustrating the state of inspecting an object in a 3D manner among the components of an X-ray inspection device (100) for reducing semiconductor inspection damage according to at least one embodiment of the present disclosure.

[0041] Referring to FIG. 4, the X-ray generator (110) according to the present disclosure can irradiate X-rays (B) in multiple directions to an object to be inspected for a 3D inspection. For example, when the X-ray generator (110) irradiates X-rays (B), the object to be inspected (T) can rotate in a preset direction through the rotation of the aforementioned manipulator (140) so that the inspection area is irradiated with X-rays (B). In addition, the X-ray generator (110) can also perform a separate rotation to irradiate X-rays (B) in multiple directions to the object to be inspected (T).

[0042] Meanwhile, the auxiliary means according to the present disclosure may be provided with a collimator (c). The collimator (c) may correspond to a configuration that ultimately controls the range in which X-rays (B) on the X-ray generator (110) are irradiated. The collimator (c) can reduce the amount of X-ray irradiation and improve the quality of image information corresponding to inspection information obtained on the detector. In particular, it may be operated in an aperture manner to control the irradiation field of the X-ray (B) output line in order to minimize the projection range of the X-ray (B) and avoid unnecessary doses.

[0043] In addition, the X-ray inspection device (100) according to the present disclosure can set the X-ray (B) irradiation range for an object (T) to be inspected through a collimator (c) and perform the aforementioned 2D inspection and 3D inspection respectively. It is also possible to perform the 2D inspection and 3D inspection sequentially in parallel. Through this, the X-ray inspection device (100) according to the present disclosure can further increase precision and reliability when X-ray inspecting an object to be inspected. The X-ray generator (110) according to the present disclosure can perform 2D inspection and inspection of a 3D area with a resolution of approximately 0.433 μm / pixel.

[0044] FIG. 5 is a diagram illustrating the state in which an X-ray inspection device according to at least one embodiment of the present disclosure selectively inspects a plurality of objects to be inspected.

[0045] Referring to FIG. 5, the X-ray generator (110) according to the present disclosure can irradiate X-rays (B) to a specific single inspection target (T1) without performing collective X-ray irradiation (B) on inspection targets (T1 to T5)) on the manipulator (140) through the aforementioned collimator (c).

[0046] In addition, although the X-ray inspection device (100) according to the present disclosure has been described as being capable of inspecting a specific inspection target (T) among a plurality of inspection targets (T1 to T5), it is also known that the X-ray inspection device (100) according to the present disclosure is capable of inspecting a specific inspection area among the overall inspection area on the inspection target (T).

[0047] Meanwhile, among semiconductors, DRAM repeatedly stores and evaporates data through the charging and discharging of electrons in an internal capacitor. Accordingly, DRAM is designed to charge electrons at intervals of approximately 100 to 200 ms. This charging cycle is called the refresh time. X-rays (B) irradiated from an X-ray inspection device (100) during X-ray inspection break down the bonding of the oxide interface of the DRAM, and at this time, electron-hole pairs (EHP) are generated, which increases the leakage current. This increase in leakage current reduces the refresh time, causing a problem known as "degradation," which leads to overload and heat generation.

[0048] The above-described inspection device (100) according to the present disclosure can enable the minimization of exposure of surrounding semiconductors by limiting the X-ray (B) irradiation range of the semiconductors to be inspected to a single semiconductor through hardware condition specifications and physical means (e.g., collimator, filter, etc.) as at least one auxiliary means.

[0049] Meanwhile, at least one of these auxiliary means may include a filter capable of attenuating a specific energy range of X-rays irradiated onto an object for inspection, and a filter capable of attenuating a specific energy range of said X-rays irradiated onto an object for inspection.

[0050] FIG. 6 is a reference drawing showing the rate of reduction of refresh time related to a damage test on an object to be inspected by an X-ray inspection device (100) according to at least one embodiment of the present disclosure. Referring to FIG. 6, according to the X-ray inspection device (100) of the present disclosure, it can be seen that the rate of reduction of refresh time in each inspection is about 10% or less during the process of performing inspections from 1 to 4 times.

[0051] Hereinafter, an X-ray generator according to various embodiments of the present disclosure will be described.

[0052] FIG. 7 is a schematic cross-sectional view showing the aforementioned X-ray generator according to at least one embodiment of the present disclosure. FIG. 8 is an enlarged view showing the portion ² shown in FIG. 7.

[0053] Referring to FIGS. 7 and 8, the X-ray generator includes a source unit (1120), a high-voltage power unit (1140), and an electron gun unit (1160). The source unit (1120) that irradiates X-rays includes a vacuum forming unit (1121) and a detachable unit (1123). The vacuum forming unit (1121) is a part in which a vacuum is formed in an internal space (S1) by vacuum pressure generated from a vacuum source (not shown), for example, a vacuum pump, through a pipe (1122) connected to one side. The vacuum forming unit (1121) may be formed in a tubular shape, but is not limited thereto and can be implemented in various forms. The vacuum forming unit (1121) may also be referred to as a vacuum chamber.

[0054] The detachable part (1123) is equipped with a target (1124) at its tip and is positioned on the upper side of the vacuum forming part (1121). At this time, the detachable part (1123) is hinged to the vacuum forming part (1121) so as to rotate to one side to open the upper side of the vacuum forming part (1121) when replacing or maintaining the electron gun unit (1160) positioned inside the vacuum forming part (1121).

[0055] Additionally, the detachable part (1123) is provided with an electron path (1125) for guiding electrons emitted from the electron gun unit (1160) to a target (1124), and coils (1127a, 1127b) surrounding the electron path (1125) are provided together.

[0056] Meanwhile, the high-voltage power supply unit (1140) (refer to FIG. 3) has a groove (1141a) formed on the upper surface where the electron gun unit (1160) is mounted to secure a space (S2) for vacuum insulation. The groove (1141a) is closed by the bottom surface (1161) of the electron gun unit (1160) to provide a space where a vacuum can be formed.

[0057] FIG. 9 is a schematic diagram illustrating pulsed X-ray (B) irradiation of an X-ray generator according to the present disclosure. FIG. 8c is a reference diagram comparing pulsed X-ray (B) irradiation according to the present disclosure with X-ray irradiation by a general beam method.

[0058] Referring to FIG. 9, the electron gun unit (1160) can generate electrons toward the target (1124). In particular, the electron gun unit (1160) can generate electrons in a pulse manner rather than in the form of a continuous beam. The electron gun unit (1160) can receive power from the high-voltage power supply unit (1140) and emit electrons toward the target in a pulse manner.

[0059] Referring to FIG. 10, the electron gun unit (1160) according to the present disclosure can irradiate a target with a pulsed first X-ray (P1) with the dose applied to the target reduced to, for example, about 1 / 2 compared to an X-ray (P0) based on a general beam method, a pulsed second X-ray (P2) with the dose reduced to about 1 / 4, and a pulsed third X-ray (P3) with the dose reduced to about 1 / 8.

[0060] Meanwhile, the detector (130) may have an image acquisition period (1301a) for acquiring an image of an object to be inspected and an information transmission period (1301b) for acquiring information. The aforementioned first X-ray (P1) to third X-ray (P3) may be irradiated within the image acquisition period (1301a) of the detector (130).

[0061] The X-ray inspection device (100) according to the present disclosure has the effect of reducing damage on the semiconductor caused by the dose because it provides a reduced dose to the object.

[0062] Meanwhile, the electron gun unit (1160) includes an insulating body (1161) and a filament (F) and a grid (not shown) installed at the tip of the insulating body (1161), as shown in FIGS. 8 and 11. The insulating body (1161) is detachably coupled to the top of the high-voltage power supply unit (1140) by a plurality of fixing bolts (1163).

[0063] In this case, the electron gun unit (1160) has a flange portion (1162) formed on its lower outer circumference, and a plurality of through holes (1162a) through which the plurality of fixing bolts (1163) pass are formed. Additionally, the flange portion (1162) has a communication hole (1165) formed to mutually communicate with the vacuum forming portion (1121) and the groove (1141a) for vacuum insulation.

[0064] As such, the X-ray generator according to the first embodiment of the present disclosure adopts a structure in which the connection between the high-voltage power supply unit (1140) and the electron gun unit (1160) is directly detachably coupled, and direct electrical connection can be made without a high-voltage insulating cable, thereby fundamentally eliminating all problems associated with the insulating silicone coating work performed when coupling between a high-voltage insulating cable and a receptacle as in the past.

[0065] In addition, when replacing the filament, the surface of the electron gun unit (1160) becomes contaminated, and if the electron gun unit (1160) is damaged due to such contamination, the electron gun unit (1160) can be easily separated from the high-voltage power supply (1140) and easily replaced with a new electron gun unit. Therefore, compared to the case where a conventional high-voltage insulated cable is used, the work can be performed easily without being significantly affected by the skill level of the worker.

[0066] Furthermore, the replacement and maintenance of the electron gun unit (1160) can be easily performed without being significantly affected by the skill level of the operator. In addition, the cost of manufacturing auxiliary means can be reduced by omitting the use of expensive high-voltage insulating cables (115). Referring to FIG. 12, the X-ray generator according to various embodiments of the present disclosure adopts a structure in which the high-voltage power supply unit (1140a) and the electron gun unit (1160a) are separated without high-voltage insulating cables (115) and simultaneously directly electrically connected, similar to the first embodiment.

[0067] Since most of the configuration of the X-ray generator in FIG. 12 can be made identical to that of the first embodiment, the same description is omitted, and a configuration different from the first embodiment is described below.

[0068] The X-ray generator of FIG. 12 has a structure different from the first embodiment in that the high-voltage power supply unit (1140a) is fixedly coupled and positioned on the side of the vacuum forming unit (1121). That is, the high-voltage power supply unit (1140) and the electron gun unit (1160) of the first embodiment are positioned in the same direction as the length direction of the vacuum forming unit (1121) and the detachable unit (1123), whereas the high-voltage power supply unit (1140a) and the electron gun unit (1160a) of various embodiments of the present disclosure are positioned perpendicular to the length direction of the vacuum forming unit (1121) and the detachable unit (1123). In this case, the electron gun unit (1160a) is formed by bending the tip of the electron gun unit (1160a), on which a filament (F) and a grid (not shown) are installed, so that it is positioned concentrically with the target (1124).

[0069] The housing surrounding the X-ray generator for radiation shielding is typically made of shielding material (such as lead or high-density materials), but such shielding is expensive and heavy. Therefore, lowering the overall height of the X-ray generator allows the size (height) of the housing to be reduced as well, offering the advantage of reducing weight and manufacturing costs.

[0070] Meanwhile, in the X-ray generator of the various embodiments described above, the connector portion for electrical connection between the high-voltage power supply unit (1140, 1140a) and the electron gun unit (1160, 1160a) may be formed using an elastic contact method as shown in FIG. 13, rather than a socket method (see FIG. 8). That is, in the elastic contact method, the connector (1167) of the electron gun unit (1160, 1160a) is maintained as is, and the connector of the high-voltage power supply unit (1140, 1140a) is made of a connector made of a predetermined elastic material, so that when the electron gun unit (1160, 1160a) is mounted on the high-voltage power supply unit (1140, 1140a), the connectors (1142a, 1167) can be connected to each other by naturally and elastically adhering to each other.

[0071] FIG. 14 is a drawing illustrating the external appearance of an X-ray generator. Referring to FIG. 14, the X-ray generator can handle a target (1124) through a separate target adjustment unit (117). Specifically, the target adjustment unit (117) can rotate the target (1124) according to a preset time and adjust the position of the target (1124) so ​​that the target (1124) is positioned on the X-ray.

[0072] The target adjustment unit (117) may include a first part (1171) and a second part (1172). The first part (1171) may be a part located on the generator (110) and equipped with a target (1124). The second part (1172) may be a part connected to the first part (1171) on the side of the X-ray generator. The first part (1171) and the second part (1172) may correspond to a configuration that rotates the target (1124) around the first part (1171) based on a plurality of gear linkages (G1 to G4).

[0073] The target adjustment unit (117) is positioned to create an eccentricity between the center of the lens unit that focuses the electron beam and the center of the target (1124) so ​​that the electron beam is focused at a location away from the center of the target (1124), and can automatically rotate the target (1124) at specific times. Therefore, when the surface of the target (1124) at the electron beam focusing location reaches the end of its lifespan, a new surface of the target (1124) is positioned through automatic rotation, allowing for continuous use without replacing the target (1124).

[0074] FIG. 15 is a drawing illustrating the interior of an X-ray generator. Referring to FIG. 15, the X-ray generator according to the present disclosure may be provided with a deflection means (1145). The deflection means (1145) is provided on the lower side of the target (1124) and may be provided with a deflection means (1145) that causes the electron beam to be deflected in one direction based on a magnetic field before the electron beam collides with the target (1124).

[0075] Although various embodiments of the present disclosure have been described individually above, each embodiment is not necessarily required to be implemented alone, and the configuration and operation of each embodiment may be implemented in combination with at least one other embodiment. Furthermore, although preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above, and various modifications can be made by those skilled in the art without departing from the gist of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical spirit or perspective of the present disclosure.

Claims

1. As an X-ray inspection device, Manipulator; A handling unit that handles an object to be inspected and positions it on the manipulator; An X-ray generator for irradiating X-rays onto an object to be inspected located on the manipulator; and A detector that receives the X-ray that has passed through the object to be inspected; comprising The above-mentioned test object includes High Bandwidth Memory, and The above X-ray generator is, A vacuum forming part in which the interior is selectively vacuum-formed; A high-voltage power supply connected to the above vacuum forming unit; A detachable part detachably installed at the tip of the vacuum forming part and having a target at the tip; and An X-ray inspection device comprising: an electron gun unit that receives power from the above-mentioned high-voltage power supply and emits electrons toward the above-mentioned target.

2. In Paragraph 1, The above X-ray inspection device is, An X-ray inspection device that performs an inspection by placing at least one auxiliary means between the object to be inspected and the X-ray generator to prevent amplification of the leakage current when the leakage current generated on the semiconductor is exposed to the X-ray.

3. In Paragraph 2, The above X-ray generator is an X-ray inspection device having, as a specification, a tube voltage value of 40 to 160 kV, a maximum output value of 80 W, and a minimum X-ray focal spot value of 0.2 to 10 µm.

4. In Paragraph 1, The above electron gun unit is an X-ray inspection device that receives power from the above high-voltage power supply and emits electrons toward the target in a pulsed manner.

5. In Paragraph 2, The above-mentioned at least one auxiliary means is, An X-ray inspection device comprising a collimator that controls the irradiation range of the X-rays irradiated onto the inspection target.

6. In Paragraph 5, The above collimator is movable in position from the above X-ray generator, and An X-ray inspection device in which the X-ray generator performs at least one of 2D inspection and 3D inspection of the object to be inspected through the collimator.

7. In Paragraph 2, The above-mentioned at least one auxiliary means is, An X-ray inspection device comprising a filter capable of attenuating a specific energy range of the X-ray irradiated onto the object to be inspected.

8. In Paragraph 1, The above X-ray generator is, An X-ray inspection device that arranges a deflection means between the vacuum forming part and the target to shift the position of the electron reaching the target.

9. In Paragraph 1, The above X-ray generator is, An X-ray inspection device comprising a target adjustment unit capable of rotating the above target according to a set time.

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