Measurement device and measurement method

Abstract

Provided is a measurement device comprising: a plate-shaped transparent member that can transmit a far infrared ray radiated from a device under test which produces heat; a pusher that has formed therein a refrigerant flow path through which a refrigerant for cooling the device under test circulates via the transparent member, and that causes the transparent member to abut the device under test by moving the transparent member toward the device under test; a lens system that is exposed to the refrigerant flow path by being inserted into a through-hole penetrating the pusher; and a temperature measurement unit that measures the temperate distribution of the device under test by detecting the far infrared ray radiated from the device under test via the transparent member, the refrigerant flow path, and the lens system while the device under test is operated.

Description

Measuring device and measuring method

[0001] The present invention relates to a measurement device and a measurement method.

[0002] Patent Document 1 states the following (abstract): "A magnetic field detector such as a SQUID detects the strength of the magnetic field, based on which a scan magnetic field image is produced. A display device superimposes the scan magnetic field image on a scan laser microphotograph on a screen, so it is possible to perform defect inspection on the semiconductor device chip."Patent Document 2 states, ``The DUT 101 emits the EM radiation 201 from a certain location, eg an antenna on the DUT 101. For example, the EM radiation 201 has a frequency of 50 MHz. At a certain location in the medium 103, the resonance frequency of the medium 103 can match the frequency of the EM radiation. luminesce, of the medium 103, which can be detected by the image detector 107. In particular, the processor is configured to analyze the acquired image and to determine the frequency of the EM radiation based on the location and / or a shape of features in the intensity profile depicted in the image. (Machine translation: DUT 101 emits EM radiation 201 from a particular location, for example, location. For example, the electromagnetic radiation 201 has a frequency of 50 MHz. At a particular position within medium 103, the resonant frequency of medium 103 may match the frequency of the EM radiation. At said position, EM radiation 201 changes the optical parameters of medium 103, in particular its light emission, which can be detected by image detector 107. In particular, the processor is configured to analyze the acquired image and determine the frequency of the EM radiation based on the position and / or shape of features in the intensity profile depicted in the image.)" (0083).Patent Document 3 states, "The insulation defect detection apparatus comprises a quantum sensor arranged near a current transformer, a laser generator for emitting a laser to the quantum sensor to excite the quantum sensor, a microwave transceiver for transmitting a microwave signal to the quantum sensor and receiving a microwave signal fed back by the quantum sensor..." (English translation of abstract). [Prior art documents] [Patent documents] [Patent document 1] US2002106820A1 [Patent document 2] US2021349142A1 [Patent document 3] CN107807342A. General disclosure

[0003] A first aspect of the present invention provides a measurement device comprising: a plate-shaped transparent member that is transmissive to far-infrared rays radiated from a device under test that generates heat; a pusher that has a refrigerant flow path formed through the transparent member through which a refrigerant for cooling the device under test flows and that moves the transparent member toward the device under test to bring the transparent member into contact with the device under test; a lens system that is inserted into a through-hole that penetrates the pusher and is exposed to the refrigerant flow path; and a temperature measurement unit that measures a temperature distribution of the device under test by detecting the far-infrared rays radiated from the device under test via the transparent member, the refrigerant flow path, and the lens system while the device under test is in an operating state.

[0004] In the above measurement apparatus, the temperature measurement section may measure the temperature distribution of the device under test during a transitional period of temperature rise of the device under test before the temperature of the device under test has stabilized after starting operation.

[0005] In any of the above-mentioned measuring devices, the positional relationship of the temperature measuring unit and the lens system relative to the device under test in the optical axis direction of the lens system may be designed in advance so that, when the transparent member is in contact with the device under test, image light from the device under test is formed on the light receiving surface of the temperature measuring unit via the transparent member, the refrigerant flow path through which the refrigerant flows, and the lens system.

[0006] In any of the above measurement devices, the temperature measurement unit may generate an image signal of the measured temperature distribution. Any of the above measurement devices may further include an image processing unit that processes the image signal input from the temperature measurement unit to generate an image of the temperature distribution of the device under test.

[0007] A second aspect of the present invention provides a measurement method comprising: moving a plate-shaped transparent member that is transmissive to far-infrared rays radiated from a device under test that generates heat toward the device under test to bring the transparent member into contact with the device under test; and, while the device under test is in an operating state, cooling the device under test by flowing a coolant through a coolant flow path at least partially surrounded by the transparent member, thereby measuring a temperature distribution of the device under test by detecting the far-infrared rays radiated from the device under test via the transparent member and the coolant flow path.

[0008] The above summary of the invention does not list all of the features of the present invention, and subcombinations of these features may also be inventions.

[0009] 1 is a schematic oblique perspective view of a measuring apparatus 100 according to one embodiment that measures the temperature distribution of a device under test 10. FIG. 2 is a schematic cross-sectional view showing a state before a pusher 160 and the like of the measuring apparatus 100 according to one embodiment come into contact with the device under test 10. FIG. 3 is a schematic cross-sectional view showing a state after a pusher 160 and the like of the measuring apparatus 100 according to one embodiment come into contact with the device under test 10. FIG. 4 shows an example of the temperature distribution of a device under test 10 visualized by the measuring apparatus 100 according to one embodiment.

[0010] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention as claimed. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0011] FIG. 1 is a schematic oblique perspective view of a measurement apparatus 100 for measuring the temperature distribution of a device under test 10 according to one embodiment. FIG. 1 shows X, Y, and Z axes that are orthogonal to each other. The X axis extends in the depth direction into the page, the Y axis extends left and right into the page, and the Z axis extends up and down into the page. The following figures also show the corresponding X, Y, and Z axes, and redundant explanations will be omitted.

[0012] The measurement device 100 includes a lens system 133, a temperature measurement unit 140, a pusher 160, and a transparent member 170. The measurement device 100 according to this embodiment may further include an image processing unit 150, a storage unit 180, and a performance board 190. Fig. 1 shows the lens system 133, the temperature measurement unit 140, the pusher 160, and the transparent member 170 in a see-through manner.

[0013] The device under test 10, which is the object of measurement by the measuring apparatus 100, is a semiconductor device, and may be, for example, an image sensor, a CMOS sensor, a CCD sensor, etc. The device under test 10 is, for example, produced by dicing a wafer into individual pieces, which are then sealed with resin and packaged.

[0014] The lens system 133 may be composed of one or more lenses. The lens system 133 is arranged so that the optical axis of the lens system 133 is parallel to the Z axis. The lens system 133 condenses far-infrared rays emitted from the device under test 10 in operation and incident on the lens system 133 from the negative side of the Z axis. The lens system 133 is inserted and fixed in a through-hole that passes through the pusher 160 in the Z axis direction. As will be described in detail later, the lens system 133 may be positioned in the Z axis direction so that no air layer is interposed between the lens system 133 and the refrigerant flowing through the refrigerant flow path formed in the pusher 160.

[0015] The temperature measurement unit 140 measures the temperature distribution of the device under test 10. The temperature measurement unit 140 is, for example, a thermo camera. A thermo camera may also be called a thermal camera. The temperature measurement unit 140 according to this embodiment detects far-infrared rays emitted from the device under test 10 in an operating state via the lens system 133.

[0016] The intensity of the far-infrared rays detected by the temperature measurement section 140 is stronger in areas of the device under test 10 where the temperature is higher, and weaker in areas of the device under test where the temperature is lower. The temperature measurement section 140 measures the two-dimensional temperature distribution on the main surface of the device under test 10 parallel to the XY plane from the intensity of the far-infrared rays. The temperature measurement section 140 generates an image signal of the measured temperature distribution and outputs it to the image processing section 150. The temperature measurement section 140 is connected to the image processing section 150 by wire so as to output the image signal to the image processing section 150. The temperature measurement section 140 may also be connected to the image processing section 150 wirelessly. The main surface of the device under test 10 parallel to the XY plane is, for example, a rectangle with a side length of approximately 10 to 30 mm.

[0017] The image processing unit 150 processes the image signal input from the temperature measuring unit 140 to generate an image of the temperature distribution on the main surface of the device under test 10. That is, the image processing unit 150 generates an image of the temperature distribution according to the intensity distribution on the main surface of the far-infrared rays detected by the temperature measuring unit 140. The image processing unit 150 may generate a thermograph in which high-temperature areas on the main surface of the device under test 10 are displayed in red and low-temperature areas are displayed in blue. The image processing unit 150 may display the generated image on a monitor.

[0018] The pusher 160 has a refrigerant flow path formed therein through which a refrigerant for cooling the device under test 10 flows via the transparent member 170. The pusher 160 moves the transparent member 170 toward the device under test 10 and brings the transparent member 170 into contact with the device under test 10.

[0019] More specifically, the pusher 160 is a structure that is raised and lowered in the Z-axis direction by a drive mechanism (not shown) together with the lens system 133 and transparent member 170 fixed to the pusher 160, and is pressed against or pulled away from the device under test 10. The above-mentioned temperature measurement unit 140 may also be fixed to the pusher 160, that is, all of these may be raised and lowered in the Z-axis direction as a unit. The pusher 160 may also be referred to as a lid, a socket, or the like.

[0020] The coolant flow path formed in the pusher 160 is a hollow portion extending in the X-axis direction and surrounded by the pusher 160 and the transparent member 170. The lens system 133 is exposed to the coolant flow path through the above-mentioned through-hole formed in the pusher 160. As shown by the arrows in FIG. 1 , a gas or liquid flows in the coolant flow path as a coolant for cooling the device under test 10. For example, water may flow in the coolant flow path. The periphery of the coolant flow path is sealed by a shield structure to prevent the coolant from leaking to the outside. The coolant flow path is configured to circulate the coolant, including areas not shown.

[0021] The transparent member 170 is, for example, glass, and is a plate-shaped optical member that can transmit far infrared rays emitted from the device under test 10 .

[0022] The accommodation section 180 is a frame that accommodates the device under test 10 on its main surface on the positive side of the Z axis. The performance board 190 has the accommodation section 180 placed on its main surface on the positive side of the Z axis. The performance board 190 is electrically connected to the device under test 10 accommodated in the accommodation section 180, and supplies power to the device under test 10 to put the device under test 10 into an operating state.

[0023] Fig. 2 is a schematic cross-sectional view showing a state before the pusher 160 and other components of the measuring apparatus 100 according to one embodiment come into contact with the device under test 10. Fig. 3 is a schematic cross-sectional view showing a state after the pusher 160 and other components of the measuring apparatus 100 according to one embodiment come into contact with the device under test 10. In Fig. 2, the direction in which the pusher 160 and other components move up and down is indicated by an outline arrow. Note that in the cross-sectional views of Figs. 2 and 3, only some components are shown hatched simply to clarify the explanation.

[0024] 2 and 3 , the device under test 10 of this embodiment includes one or more dies 11, a package 13 in which the one or more dies 11 are sealed with resin, and an interposer 15 electrically connected to the one or more dies 11. The device under test 10 may have a multi-package structure including multiple dies 11, or a single-package structure including one die 11.

[0025] 2 , the measuring apparatus 100 according to this embodiment accommodates the device under test 10 in the accommodation section 180 with the pusher 160 and the like separated in the Z-axis direction from the accommodation section 180 and the performance board 190. The device under test 10 accommodated in the accommodation section 180 is electrically connected to the performance board 190.

[0026] 3 , the measurement apparatus 100 according to this embodiment moves the pusher 160 and the like in the Z-axis direction toward the device under test 10 to bring the transparent member 170 into contact with the device under test 10. In this state, the positional relationship of the temperature measurement section 140 and the lens system 133 relative to the device under test 10 in the optical axis direction of the lens system 133 is designed in advance so that image light from the device under test 10 forms an image on the light-receiving surface of the temperature measurement section 140 via the transparent member 170, the refrigerant flow path through which the refrigerant flows, and the lens system 133.

[0027] The measuring apparatus 100 according to this embodiment starts circulating the coolant through the coolant flow path of the pusher 160, starts supplying power from the performance board 190 to the device under test 10, and puts the device under test 10 into an operating state. In the device under test 10 that is now in an operating state, each of the multiple dies 11 generates heat. The measuring apparatus 100 cools the heated device under test 10 with the coolant circulating through the coolant flow path.

[0028] The measuring apparatus 100 measures the temperature distribution of the device under test 10 while the device under test 10 is operating. With the transparent member 170 in contact with the device under test 10, the measuring apparatus 100 measures the temperature distribution on the main surface of the device under test 10 while cooling the device under test 10 by flowing a refrigerant with controlled temperature and flow rate through a refrigerant flow path, and visualizes the measured temperature distribution. FIG. 4 shows an example of the temperature distribution of the device under test 10 visualized by the measuring apparatus 100 according to an embodiment. In FIG. 4, the temperature level is indicated by different shades of gray, with darker colors indicating higher temperatures. The image processing unit 150 of the measuring apparatus 100 may generate an image of the temperature distribution shown in FIG. 4, for example, and display it on a monitor.

[0029] The temperature distribution in the device under test 10 becomes uniform as a whole after the temperature rise ceases and the temperature stabilizes over time after the multiple dies 11 start operating. A uniform temperature distribution can make it difficult to identify a die 11 in the device under test 10 that is relatively hot. Therefore, the measuring apparatus 100 suppresses the temperature rise of the device under test 10 that has started operating, and measures the temperature distribution of the device under test 10 before the temperature of the device under test 10 stabilizes, i.e., during the temperature rise transition period. That is, the temperature measuring section 140 measures the temperature distribution of the device under test 10 during the temperature rise transition period of the device under test 10 before the temperature of the device under test 10 that has started operating stabilizes. The temperature measuring section 140 may start measuring the temperature distribution of the device under test 10 when a predetermined time has elapsed since the start of power supply to the device under test 10. The measuring apparatus 100 may vary the predetermined time by adjusting the flow rate of the coolant flowing through the coolant flow path. The temperature of the device under test 10 measured by the measuring apparatus 100 may be up to about 150°C.

[0030] Here, as a comparative example to the measuring device 100 according to this embodiment, we will assume a measuring device in which a temperature control unit such as a heat sink or air-cooling fan is placed over the device under test 10 to prevent the device under test 10 from generating heat, and the temperature of the device under test 10 is controlled by the temperature control unit while measuring the temperature distribution of the device under test 10.

[0031] As described above, when the device under test 10 is operated, one or more dies 11 included in the device under test 10 generate heat. The heat generation behavior of the device under test 10 varies due to individual differences between the dies 11 in the device under test 10. In so-called chiplet or 3D packaging, multiple dies 11 are included in the same package, and dies 11 from multiple vendors are mixed, making heat generation prediction and control more complicated, and raising concerns about damage such as cracks to each die 11, interposer 15, and their contact points, which have different expansion coefficients. In the measurement device of the comparative example, a temperature control unit is attached to the device under test 10, so it is impossible to determine from the outside how the device under test 10 is generating heat.

[0032] As another comparative example of the measurement apparatus 100 according to this embodiment, a measurement method is assumed in which temperature sensors, such as DTSs and thermal diodes, are incorporated into the package of the device under test 10 to measure the temperature distribution of the device under test 10. According to this measurement method, the number and locations at which temperature sensors can be incorporated are limited, and the device under test 10 is packaged with temperature sensors incorporated in locations predicted to be hot during the design of the device under test 10. However, the locations that become hot during actual operation of the device under test 10 may differ significantly from the predicted locations. It is not possible to install the temperature sensor in an optimal location that takes into account the influence of adjacent dies 11, making it difficult to predict the optimal location. Because the device under test 10 is also packaged, the location of the temperature sensor cannot be changed. Furthermore, due to circuit constraints on the device under test 10, it may not be possible to place the temperature sensor where desired. Furthermore, the heat generation distribution of a single die 11 may differ from the critical heat generation points when multiple dies 11 are packaged. Therefore, it is not possible to pinpoint the desired temperature measurement location. Temperature anomalies can occur at points other than the sensing point, making it impossible to read all the data. Furthermore, in FinFETs, GAAs, CFETs, and other devices, there is no place for heat to escape and heat sources are inherent, making temperature analysis and appropriate control even more critical, and ensuring reliability is difficult.

[0033] In contrast, with the measuring apparatus 100 according to this embodiment, a transparent member 170 that transmits far-infrared rays radiated from a heat-generating device under test 10 is moved toward the device under test 10 and brought into contact with the device under test 10. The measuring apparatus 100 further measures the temperature distribution of the device under test 10 by detecting far-infrared rays radiated from the device under test 10 via the transparent member 170 and the coolant flow path while cooling the device under test 10 by flowing a coolant through a coolant flow path at least partially surrounded by the transparent member 170 while the device under test 10 is in operation. This allows the measuring apparatus 100 to simultaneously measure the temperature of multiple sensing points across the entire surface of the device under test 10 while suppressing a temperature rise in the device under test 10 that has started operating, even with one or more dies 11 still packaged, regardless of the circuit area or design of the device under test 10. This allows the measuring apparatus 100 to visualize the temperature distribution of the device under test 10.

[0034] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0035] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order.

[0036] REFERENCE SIGNS LIST 10 Device under test 11 Die 13 Package 15 Interposer 100 Measurement device 133 Lens system 140 Temperature measurement unit 150 Image processing unit 160 Pusher 170 Transparent member 180 Storage unit 190 Performance board

Claims

1. A measurement device comprising: a plate-shaped transparent member that can transmit far-infrared rays radiated from a device under test that generates heat; a pusher that has a refrigerant flow path formed through the transparent member through which a refrigerant for cooling the device under test flows, and that moves the transparent member toward the device under test to bring the transparent member into contact with the device under test; a lens system that is inserted into a through-hole that passes through the pusher and is exposed to the refrigerant flow path; and a temperature measurement unit that measures the temperature distribution of the device under test by detecting the far-infrared rays radiated from the device under test via the transparent member, the refrigerant flow path, and the lens system while the device under test is in operation.

2. The measurement device according to claim 1, wherein the temperature measurement section measures the temperature distribution of the device under test during a transitional period of temperature rise of the device under test before the temperature of the device under test has stabilized after starting operation.

3. The measurement device according to claim 1, wherein the positional relationship of the temperature measurement unit and the lens system relative to the device under test in the optical axis direction of the lens system is designed in advance so that, when the transparent member is in contact with the device under test, image light from the device under test is formed on the light-receiving surface of the temperature measurement unit via the transparent member, the refrigerant flow path through which the refrigerant flows, and the lens system.

4. The measurement device according to claim 1, wherein the temperature measurement unit generates an image signal of the measured temperature distribution, and further comprises an image processing unit that generates an image of the temperature distribution of the device under test by image processing the image signal input from the temperature measurement unit.

5. A measurement method comprising: moving a plate-shaped transparent member that is transparent to far-infrared rays radiated from a heat-generating device under test toward the device under test and bringing the transparent member into contact with the device under test; and measuring the temperature distribution of the device under test by detecting the far-infrared rays radiated from the device under test via the transparent member and the coolant flow path while cooling the device under test by flowing a coolant through a coolant flow path at least partially surrounded by the transparent member while the device under test is in an operating state.

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