KR102679089B1 - X-ray inspection apparatus with scan speed improving function - Google Patents

Abstract

The present invention relates to an An X-ray inspection device having a scanning speed improvement structure including:

Description

X-ray inspection device with scan speed improvement structure {X-RAY INSPECTION APPARATUS WITH SCAN SPEED IMPROVING FUNCTION}

The present invention relates to sample inspection technology using X-rays, and more specifically, to an X-ray inspection device that can simultaneously secure economics and safety by improving inspection speed.

A CT (Computed Tomography) device rotates an output source of radiation such as It refers to a device that is acquired and is currently being distributed to various industries.

These CT devices have the advantage of being able to determine defects without cutting or disassembling the test object. CT equipment mainly used for medical purposes fixes the test object and rotates the imaging device to take It is a device that obtains images.

Due to the advantage of being able to destroy the inside of an object to be inspected in a non-destructive manner, CT devices are being applied to a wide range of industrial fields, and numerous research and development efforts are being conducted to suit the special characteristics of each field. A representative industrial field is the semiconductor field, where semiconductor chips are stacked and designed through packaging techniques, which is the only way to increase the directness of semiconductors.

Such packaging is inspected using X-ray inspection to check for cracks in the chip or the connection between chips. At this time, the use of 3D tomography is essential due to the complex structure of the packaged chip. In other words, the development of chips with improved integration must be accompanied by the development of more precise and applicable CT inspection equipment.

Previously, it was limited to inspecting the single layer of an object through simple 2D image acquisition, but the demand for 3D inspection to understand three-dimensional changes is increasing, and many imaging and inspection technologies for PCB boards are being developed and distributed. am.

Korean Patent No. 10-1351809 discloses a conventional X-ray inspection system for plate-shaped inspection objects, and Figure 1 is a conceptual diagram thereof.

Looking at this in detail, an X-ray generator 130 that radiates an A technology for implementing the detection signal into an image of the object to be inspected (200) is being disclosed.

In order to inspect thin plates like this, it is necessary to construct dedicated equipment, and defects in contact points or device placement problems are usually detected through 2D images. However, in recent years, the density of substrates has increased and multiple layers are implemented on a single substrate, which has led to limitations in inspection using conventional inspection.

To solve this problem, improvements have been made to the method of performing tomography by rotating the substrate, and in some cases, a method of inspecting by changing the position of the X-ray generator or detector has been proposed. Industrial automated X-ray inspection (AXI: Automated

In recent years, this 3D inspection method has been preferred due to the complexity and diversification of equipment, and the speed of inspection affects the speed of overall logistics and thus determines the economic feasibility of the overall process.

The present invention was devised to solve the above-mentioned problems, and its purpose is to provide an Do it as

In order to solve the above problem, the present invention includes a tube that emits X-rays to a sample, a first detector that generates a detection signal for the X-rays from the tube and is transported along a circular detector transfer path, and A second detector that generates a detection signal and is symmetrically placed and transported relative to the center point with respect to the first detector, and is synchronized with the first detector and transported along a circular detector transport path, the first detector and the second detector. An X-ray inspection device including a control unit that controls the transfer of

The first detector and the second detector may acquire an X-ray image by dividing a portion of the entire rotation angle during the scanning process for one sample.

In addition, it is desirable to include a transfer path in the beam area of the tube and to acquire images for each rotation section of 180 degrees or more with respect to the entire rotation angle during the scanning process for one sample.

The end position of the first detector may have a more rotated angle than the start position of the second detector.

Additionally, the control unit can omit the zero point setting process by setting the end position where the scanning process for one sample is completed as the starting position for the scanning process for the next sample.

The control unit may control the rotation directions of the first detector and the second detector when scanning one sample and the rotation directions of the first detector and the second detector when scanning the next sample in opposite directions.

The control unit may transfer the first detector and the second detector by setting the radius of the detector transfer path differently depending on the type of sample.

Meanwhile, the tube may be composed of a first tube corresponding to the first detector and a second tube corresponding to the second detector.

According to the configuration of the present invention described above, the tact time for conventional sample inspection can be reduced by less than half, thereby improving the speed and economic efficiency of the process.

In addition, since the zero-point setting process is omitted at the end of one scan process and continuous next scans are possible, the procedure is simplified during continuous inspection, which not only contributes to reducing time, but also eliminates the possibility of errors.

In addition, due to time savings, radiation exposure caused by exposure to X-rays can be reduced, which has the effect of minimizing the possibility of deterioration or injury.

Figure 1 is a conceptual diagram of a conventional X-ray inspection system for a plate-shaped inspection object.
Figure 2 is a conceptual diagram of an X-ray inspection device having a scan speed improvement structure according to the concept of the present invention.
Figure 3 is a diagram for explaining how detectors are controlled to transport in the X-ray inspection device having the scan speed improvement structure of the present invention.
Figure 4 is a configuration diagram of an X-ray inspection device having a scan speed improvement structure according to an embodiment of the present invention.
Figure 5 is a plan view for explaining a structure for controlling the transport of a detector according to an embodiment of the present invention.
Figure 6 is a block diagram for explaining the control system in the X-ray inspection device having the scan speed improvement structure of the present invention.

Hereinafter, an X-ray inspection device having a scanning speed improvement structure according to the present invention will be described in more detail with reference to the attached drawings.

The following embodiments combine the components and features of the present invention in a predetermined form. Each component or feature may be considered optional unless explicitly stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. Additionally, some components and/or features may be combined to form an embodiment of the present invention. The order of operations described in embodiments of the present invention may be changed. Some features or features of one embodiment may be included in other embodiments or may be replaced with corresponding features or features of other embodiments.

In the description of the drawings, parts, devices, and/or configurations that may obscure the gist of the present invention are not described, and parts, devices, and/or configurations that can be understood at a level by those skilled in the art are not described. Additionally, parts referred to using the same reference numerals in the drawings refer to the same components or steps in the device configuration or method.

Throughout the specification, when a part is said to “comprise or include” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary. do. Additionally, terms such as “···unit” or “···unit” used in the specification refer to a unit that processes at least one function or operation. In addition, the terms "a or an", "one", "the", and similar related terms are used in the context of describing the invention (particularly in the context of the claims below) as used herein. It may be used in both singular and plural terms, unless indicated otherwise or clearly contradicted by context.

The present invention basically provides an

In the present invention, samples subject to X-ray inspection may be inspection objects such as substrates, BGA (Ball Grid Array), semiconductors, wafers, and batteries, and the types of inspection objects are not limited to the description of the present invention.

In addition, as long as the detectors have a rotating transfer path, the type of X-ray inspection equipment or method is not limited, and various known technologies of X-ray inspection equipment may be applied to parts not described in the present invention.

Figure 2 is a conceptual diagram of an X-ray inspection device having a scan speed improvement structure according to the concept of the present invention.

A tube and detector are configured on a predetermined stage, and the test is performed by acquiring an X-ray image of the sample. The X-ray image obtained here may be 3D or 2D, and the type is not limited.

Like general X-ray examination equipment, an However, it is not limited to the above arrangement.

Examples of the overall configuration including the tube will be described later.

According to the concept of the present invention, the detectors are composed of a pair and are synchronized and transported along one circular orbit. Accordingly, the detector may be composed of a first detector 1210 and a second detector 1220, and share the detector transfer path 2010.

The detector transfer path 2010 forms a circular orbit, and the reference positions of the first detector 1210 and the second detector 1220 are arranged in the radial direction. That is, the first detector 1210 and the second detector 1220 are arranged symmetrically around the center point (reference number not shown).

In the description of the present invention, saying that the detector is rotated means rotating about the center point along the detector transfer path 2010.

The first detector 1210 and the second detector 1220 transfer more than half of the path in the circumferential direction in one circular detector transfer path 2010, and each acquires an image of 180 degrees or more during this transfer process to obtain one image. Allows you to combine images. In this way, two detectors define one step covering the entire 360-degree range as one sequence. However, the total rotation path is not limited to 360 degrees, and it is sufficient if the first detector 1210 and the second detector 1220 share the entire circular or partial arc path.

The radius of the detector transfer path 2010 may vary depending on settings, and in some cases may be variable depending on the structure of a predetermined guide portion. Examples related to this will be described later.

The reference position for the detector transfer path 2010 of the detectors may be approximately the center of gravity or the coupling position to the guide unit, but if two detectors hold the same reference point, this is not limited to the above description.

When the reference position of the first detector 1210 is placed at a certain position on the detector transfer path 2010 and the inspection is started, this is defined as the starting position 2011. In the illustrated embodiment, the first detector 1210 is transferred counterclockwise, and the second detector 1220 is also synchronized with this and begins to transfer counterclockwise. The direction is indicated by an arrow.

During the transfer process, x-rays are received from the tube, an image signal is generated, transmitted to a predetermined control unit, and the images can be combined. The point at which a sequence is completed is defined as the end position (2012). Ideally, if the entire path is defined as 360 degrees, the end position (2012) may be a point rotated 180 degrees from the start position (2011), but considering errors when combining images from two detectors, the end position (2012) may be rotated 180 degrees from the start position (2011). 2012), it would be desirable to have a rotation position rotated more than 180 degrees from the starting position (2011). Accordingly, the ending position 2012 is formed at an angle θ further advanced than the point symmetrical to the starting position 2011 with respect to the center point.

Figure 3 is a diagram for explaining how detectors are controlled to transport in the X-ray inspection device having the scan speed improvement structure of the present invention.

Figure 3(a) shows, for example, the process of performing the first scan sequence. The first detector 1210 is located at approximately 2 o'clock in the detector transfer path 2010, and the second detector 1220 is located at approximately 8 o'clock, which is a point symmetrical about the center point. The starting position of the first detector 1210 is defined as the first starting position 2011a. In the process of rotating counterclockwise, images are collected and one sequence is completed, and Figure 3(b) shows the end positions of the first sequence.

Additionally, (b) in FIG. 3 may mean the starting position of the second sequence. Therefore, the end position of the first sequence starting from the first start position (2011a) and progressed by the first detector 1210 is the second start position (2011b) of the second sequence by the first detector 1210. will be.

The rotation direction of the second sequence may be considered to be continuous clockwise like the first sequence, but considering the structural simplicity and degree of freedom of the drive system, it may be preferable to be in the opposite direction to the preceding scan sequence. However, the directionality is optional.

According to this embodiment, the second sequence proceeds counterclockwise, and the first detector 1210 disposed at the second start position 2011b is located at approximately 7 o'clock. Accordingly, it can be understood that the second detector 1220 is located at approximately 1 o'clock, which corresponds to the center point.

The above process may be repeated during testing of successive samples.

In the case of the prior art, it may be seen as structurally simpler because it makes one complete rotation, but considering the process of preparing for acquisition for scanning by adjusting the zero point after completing the scan for one sample, the present invention If applied, the zero point adjustment process becomes unnecessary. In other words, note that there is an advantage in that immediate progress is possible because the completion point of one scanning process becomes the starting point of another scanning process.

In addition, because the detectors are composed of pairs, the scan can be completed with only half (or more) of rotations, so the time required for zero point adjustment is eliminated, and the time to complete one sequence is reduced to less than half compared to the conventional method. will be.

The shortening of the scanning time not only leads to economy and speed of the entire process, but also leads to the advantage of minimizing the possibility of undesirable effects on the sample or body by reducing the exposure time itself.

Figure 4 is a configuration diagram of an X-ray inspection device having a scan speed improvement structure according to an embodiment of the present invention.

In the first embodiment of the present invention, the tube is composed of a single tube. The X-ray tube may be an X-ray tube with an electron gun and a target inside, and the type is not limited as long as it is a device that emits X-rays.

Figure 4 (a) shows the first embodiment, in which a single tube 1100 is disposed on the upper side, and a first detector 1210 and a second detector 1220 and the detector transfer path ( 2010) may be included.

Figure 4(b) shows the second embodiment, in which tubes are arranged in pairs corresponding to each detector. In this case, the first tube 1110 corresponding to the first detector 1210 and the second tube 1120 corresponding to the second detector 1220 are transported together. The beam areas of the first tube 1110 and the second tube 1120 are relatively small in width, which means that the distance between the detector and the tube can be further reduced compared to the first embodiment.

The first tube 1110 and the first detector 1210 are transported in correspondence, and the second tube 1120 and the second detector 1220 are transported in correspondence, and the first detector 1210 and the second detector ( 1220) are being transferred in mutual synchronization as described above.

However, the relationship between the tube and the detector is not limited to the example shown, and the tube and the detector may form various angles to correspond to each other.

Figure 5 is a plan view for explaining a structure for controlling the transport of a detector according to an embodiment of the present invention.

Various guide structures can be considered to form a circular detector transfer path 2010. For example, structures such as circular rails, chains, and belts can be applied.

In the illustrated embodiment, the guide unit 2100 is composed of a combination of 4-axis linear guides so that each detector is transported in two axial directions and has a degree of freedom in the x-y plane. This guide unit 2100 may also be applied to a robot arm.

A driving unit 2200 capable of providing power to each axis is coupled to the guide unit 2100 as described above, and a known power generation and driving system may be applied to provide power for linear transport.

According to this configuration, the first detector 1210 and the second detector 1220 can be moved in synchronization in the arc direction with respect to the center point.

When configured as above, there is an advantage in that the radius of the detector transfer path 2010 can be adjusted compared to the case where a simple fixed circular guide is configured. Accordingly, the first detector 1210 and the second detector 1220 can be transported with a transport radius optimized for the sample.

Figure 6 is a block diagram for explaining the control system in the X-ray inspection device having the scan speed improvement structure of the present invention.

The control unit 3000 includes a tube control unit 3100 that supplies control power to the tube 1100 and controls the emission of X-rays, a detection unit 3200 that collects and combines image signals from detectors to generate an image, and It may be configured to include a transfer control unit 3300 that can synchronously control the transfer of the first detector 1210 and the second detector 1220 in the detector transfer path 2010.

Since the tube control unit 3100 and the detection unit 3200 may have configurations of known X-ray inspection equipment, their detailed description will be omitted.

The transfer control unit 3300 performs a function of controlling the process in which each detector is transferred in one sequence when the guide unit 2100 and the drive unit 2200 are configured as in the embodiment of FIG. 5.

In some cases, the transport control unit 3300 may control the transport of a single tube 1100 or the first tube 1110 and the second tube 1120 together.

Meanwhile, the control unit 3000 further includes a sequence determination unit 3400 to control the continuity of each sample test sequence.

Referring to FIG. 3, the first sequence starts from the first start position 2011a for one sample, moves each section of approximately 180°+θ, and ends at a predetermined end position, thereby completing the scan for one sample. It's done. The sequence determination unit 3400 determines the start and end of one sequence, and sets the end position of the first sequence to the second start position 2011b to proceed with scanning for the next sample. . This process applies when tubes are configured in pairs, as shown in (b) of FIG. 4.

Additionally, when there is a continuous inspection process for multiple samples and the size or shape of the sample changes as each sequence alternates, the sequence determination unit 3400 allows the transfer control unit 3300 to set the rotation radius differently. It may be variable. Accordingly, the sequence determination unit 3400 can perform scanning by automatically changing the rotation radius of a pair of detectors for each injected sample, thereby further improving the efficiency of process automation.

By using the X-ray inspection device having the scan speed improvement structure of the present invention described above, the tact time for conventional sample inspection can be reduced by less than half, thereby improving the speed and economic efficiency of the process.

In addition, since the zero-point setting process is omitted at the end of one scan process and continuous next scans are possible, the procedure during continuous inspection is simplified, which not only contributes to reducing time, but also eliminates the possibility of errors.

Additionally, due to time savings, the possibility of exposure to X-rays is minimized.

In the above, the present invention has been described in detail based on examples and accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the content described in the claims described later.

1100...tube 1110...first tube
1120...second tube 1210...first detector
1220...2nd detector 2010...detector transfer path
2011...starting location 2011a...first starting location
2011b...second start position 2012...end position
2100...guide part 2200...drive part
3000...Control unit 3100...Tube control unit
3200...detection part 3300...transfer control part
3400...Sequence judgment unit

Claims (7)

A tube that emits x-rays to the sample;
a first detector that generates a detection signal for X-rays from the tube and is transported along a circular detector transport path;
a second detector that generates a detection signal for
It includes a control unit that controls the transport of the first detector and the second detector,
The first detector and the second detector are,
An X-ray inspection device that includes a transfer path within the beam area of a tube and has a scan speed improvement structure that acquires images for each rotation section of 180 degrees or more with respect to the entire rotation angle during the scanning process for one sample.
delete According to paragraph 1,
The ending position of the first detector is,
An X-ray inspection device having a scan speed improvement structure with a more rotated angle than the starting position of the second detector.
According to paragraph 1,
The control unit,
An X-ray inspection device with a scan speed improvement structure that sets the end position where the scanning process for one sample is completed as the starting position for the scanning process for the next sample.
According to clause 4,
The control unit,
An X-ray device with a scan speed improvement structure that controls the rotation direction of the first detector and the second detector when scanning one sample and the rotation direction of the first detector and the second detector in opposite directions when scanning the next sample. Inspection device.
According to clause 4,
The control unit,
An X-ray inspection device with a scan speed improvement structure that transfers the first detector and the second detector by setting the radius of the detector transfer path differently depending on the type of sample.
According to any one of claims 1, 3 to 6,
The tube is,
An X-ray inspection device having a scan speed improvement structure consisting of a first tube corresponding to the first detector and a second tube corresponding to the second detector.

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