JP2013027956A - Destructive device and destructive method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a workload in destructing a silicon chip in a nonvolatile memory chip.SOLUTION: This destructive device 1 includes a horn 12 transmitting ultrasonic vibration to the nonvolatile memory chip 2 and an AE sensor 14 detecting elastic waves which are generated when a mold resin 2B or the silicon chip 2A in the nonvolatile memory chip 2 is destructed by the ultrasonic vibration. The destructive device 1 includes an acquisition part 21 acquiring the response power of a harmonic content of a specific frequency band from a frequency response of the elastic waves and a first determination part 22 determining whether or not the obtained response power reaches a first threshold value X1 or smaller. The destructive device 1 includes a second determination part 23 determining whether or not the obtained response output reaches a second threshold value X2 or larger after the response output reaches the first threshold value or smaller. Furthermore, the destructive device 1 includes a control part 24 controlling the horn 12 to stop the output power of the ultrasonic vibration when the obtained response output reaches the second threshold value or larger.

Description

  The present invention relates to a destruction apparatus and a destruction method.

  In recent computers, data and software to be processed increase year by year, and high-speed processing is required for a storage medium that stores these data and software. Therefore, in recent years, SSDs (Solid State Drives) capable of higher-speed processing are becoming widespread in place of HDDs (Hard Disk Drives).

  In addition, with the widespread use of storage media, there is a need for various measures that place importance on the handling of information stored in storage media and prevent leakage of the information. Therefore, as one of such measures, for example, when the SSD is discarded, there is a method of destroying the SSD itself so that information is not read from the SSD. In the case of this method, a contractor who contracts the removal of the SSD is required to present or report evidence of the completion of the destruction to the client after the destruction of the SSD is completed.

The SSD has a substrate on which a plurality of nonvolatile memory chips are mounted. The nonvolatile memory chip is configured by sealing the entire silicon chip on which information is recorded with a mold resin.
In order to satisfy the client's request for an SSD having such a configuration, a plurality of nonvolatile memory chips were individually destroyed, and all the nonvolatile memory chips mounted on the SSD were physically destroyed. The client must be able to confirm that.

  Therefore, as a physical destruction method, there is a technique for destroying the nonvolatile memory chip by making a through hole in the nonvolatile memory chip using a drill. There is also a technique of making a through hole in a nonvolatile memory chip using ultrasonic vibration. When ultrasonic vibration is used, an ultrasonic vibrator is connected to a horn attached to the tip of the cylinder, and a through hole is opened in the nonvolatile memory chip with thrust energy by the cylinder of the horn and energy by ultrasonic vibration.

  Therefore, in the physical destruction method, a non-volatile memory chip using a drill or a horn, that is, a mold resin on the front surface side of the non-volatile memory chip, a silicon chip inside the non-volatile memory chip, and a back surface side of the non-volatile memory chip is used. The mold resin is sequentially drilled. And a drill or a horn opens the through-hole which penetrates the mold resin and silicon chip which exist between the surface in a non-volatile memory chip, and a back surface in a non-volatile memory chip. As a result, the silicon chip in the nonvolatile memory chip is destroyed, and the nonvolatile memory chip is destroyed.

JP 9-57696 A JP 2006-43804 A Japanese Patent Laid-Open No. 5-115846 Japanese Patent Publication No. 7-32613 JP-A-10-315334 JP 2006-88135 A

  In order to destroy the information recorded in the nonvolatile memory chip, it is sufficient that the silicon chip in the nonvolatile memory chip can be destroyed. Therefore, it is not necessary to perforate the mold resin on the back side of the nonvolatile memory chip.

  In one aspect, an output unit that outputs ultrasonic vibration that breaks a silicon chip sealed with a resin material, and detection that detects an elastic wave generated when the resin material or the silicon chip is broken by the ultrasonic vibration Part. Furthermore, in this aspect, it has an acquisition part which acquires the response output of the harmonic component of the specific frequency band in which the said resin material and the said silicon chip resonate from the detected frequency response of the said elastic wave. Furthermore, in this aspect, the response output acquired by the acquisition unit is compared with a first threshold value that is a response output of a harmonic component in the specific frequency band generated when the silicon chip is broken by the ultrasonic vibration. And a first determination unit for determining. Furthermore, in this aspect, after the first determination unit determines that the response output of the harmonic component in the specific frequency band is equal to or less than the first threshold, the response output acquired by the acquisition unit And a second determination unit that compares and determines a second threshold value that is a response output of the harmonic component of the specific frequency band generated when the resin material is destroyed by the ultrasonic vibration. Furthermore, in this aspect, after the second determination unit determines that the response output of the harmonic component in the specific frequency band is equal to or greater than the second threshold, the ultrasonic vibration of the output unit is stopped. It has a control part.

  Drilling a mold resin on the front side of the non-volatile memory chip, then drilling a silicon chip, and if the drilling operation is stopped when the mold resin on the back side of the non-volatile memory chip is reached, the destruction due to the generation of the through hole However, it is possible to reliably achieve the above requirements in a shorter time.

FIG. 1 is a block diagram illustrating an example of a destruction apparatus according to the present embodiment. FIG. 2 is a block diagram illustrating an example of the process control unit. FIG. 3 is an explanatory diagram illustrating an example of frequency response characteristics when the mold resin and the silicon chip in the nonvolatile memory chip are destroyed. FIG. 4 is an explanatory diagram showing an example of the detection output of the AE sensor related to the nonvolatile memory chip destruction process. FIG. 5 is an explanatory diagram showing an example of a frequency response output related to the nonvolatile memory chip destruction process. FIG. 6 is an explanatory diagram illustrating an example of a relationship between a frequency response output in a specific frequency band related to the nonvolatile memory chip destruction process and a time change. FIG. 7 is an explanatory diagram showing an example of the relationship between the moving average value of the frequency response output in the specific frequency band related to the nonvolatile memory chip destruction process and the time change. FIG. 8 is an explanatory diagram showing an example of a reference threshold setting method related to the nonvolatile memory chip destruction process. FIG. 9 is an explanatory diagram showing a relationship among a reference threshold value, a first threshold value, and a second threshold value related to the nonvolatile memory chip destruction process. FIG. 10 is a flowchart illustrating an example of the processing operation of the process control unit of the destruction apparatus related to the nonvolatile memory chip destruction process. FIG. 11 is an explanatory diagram showing an example of the operation of the destruction device related to the nonvolatile memory chip destruction processing.

  Hereinafter, embodiments of a destruction apparatus and a destruction method disclosed in the present application will be described in detail based on the drawings. The disclosed technology is not limited by the present embodiment.

  FIG. 1 is a block diagram illustrating an example of a destruction apparatus according to the present embodiment. The destruction apparatus 1 shown in FIG. 1 includes a die 11, a horn 12, an actuator 13, and an acoustic emission (AE) sensor 14. Furthermore, the destruction apparatus 1 includes a preamplifier 15, a discriminator 16, a pulse oscillator 17, a stroke control unit 18, and a process control unit 19. The die 11 is a work panel on which the substrate 3 on which the nonvolatile memory chip 2 is mounted is placed. The substrate 3 is one member of a nonvolatile memory chip. The actuator 13 is a drive mechanism that drives the horn 12 in the stroke direction in accordance with a control signal from the stroke control unit 18. The stroke direction is a direction perpendicular to the die 11, that is, a direction in which the horn 12 moves relative to the die 11. The horn 12 is a part that transmits ultrasonic vibrations to the nonvolatile memory chip 2 on the substrate 3 placed on the die 11 to destroy the nonvolatile memory chip 2. The horn 12 includes a cylinder 12A that moves in the stroke direction according to the operation of the actuator 13, an ultrasonic transducer 12B that is coupled to the tip of the cylinder 12A, and a horn body 12C that is coupled to the ultrasonic transducer 12B. Have. The tip of the horn main body 12C is in contact with the surface of the nonvolatile memory chip 2 placed on the die 11 and transmits ultrasonic vibrations to the nonvolatile memory chip 2.

  The AE sensor 14 is in contact with the nonvolatile memory chip 2 to be destroyed, and detects an elastic wave generated when the nonvolatile memory chip 2 is destroyed by ultrasonic vibration of the horn 12. The AE sensor 14 is, for example, a broadband sensor that detects an elastic wave of a harmonic component in a frequency band of 100 kHz to 250 kHz. The preamplifier 15 amplifies the detection output of the AE sensor 14. The discriminator 16 discriminates the amplified detection output and executes a filtering process necessary for analysis. The pulse oscillator 17 oscillates, for example, a 28 kHz drive pulse for driving and controlling the ultrasonic transducer 12B of the horn 12. The stroke control unit 18 controls the actuator 13 to adjust the movement operation of the horn 12 in the stroke direction.

  The nonvolatile memory chip 2 includes a silicon chip 2A that stores information and a mold resin 2B that seals the silicon chip 2A. The horn 12 of the destruction device 1 is for destroying the mold resin 2B and the silicon chip 2A on the surface side of the nonvolatile memory chip 2 by ultrasonic vibration.

  FIG. 2 is a block diagram illustrating an example of the process control unit 19. The process control unit 19 illustrated in FIG. 2 includes an acquisition unit 21, a first determination unit 22, a second determination unit 23, a control unit 24, a setting unit 25, and a storage unit 26. The acquisition unit 21 obtains a frequency response output by performing frequency response calculation of the detection output of the AE sensor 14, for example, Fourier analysis. Furthermore, the acquisition unit 21 acquires a response output of a harmonic component in a specific frequency band in which the mold resin 2B and the silicon chip 2A in the nonvolatile memory chip 2 resonate from the frequency response output. FIG. 3 is an explanatory diagram showing an example of frequency response characteristics when the mold resin 2B and the silicon chip 2A in the nonvolatile memory chip 2 are destroyed. The destruction depth of the mold resin 2B in the nonvolatile memory chip 2 is 0.1 mm, and the destruction depth of the silicon chip 2A in the nonvolatile memory chip 2 is 0.6 mm. The breakdown depth refers to the depth of perforation to be applied to the mold resin 2B and the silicon chip 2A in the nonvolatile memory chip 2. When attention is paid to the frequency response characteristics of FIG. 3, the frequency response output when the mold resin 2B is broken is high at 150 kHz or higher, and the frequency response output when the silicon chip 2A is broken is high at 150 kHz or less. Therefore, in the frequency band in which the mold resin 2B and the silicon chip 2A resonate, the frequency response output generated when the mold resin 2B is broken and the silicon chip 2A is broken is high, and the difference between the frequency response outputs is maximized. A specific frequency band of 224 kHz is selected.

  FIG. 4 is an explanatory diagram showing an example of the detection output of the AE sensor 14 related to the nonvolatile memory chip destruction process. In the detection output of the AE sensor 14 shown in FIG. 4, the vertical axis represents amplitude and the horizontal axis represents frequency. FIG. 5 is an explanatory diagram showing an example of a frequency response output related to the nonvolatile memory chip destruction process. In FIG. 5, the vertical axis represents amplitude and the horizontal axis represents frequency. The acquisition unit 21 performs a Fourier analysis on the detection output of the AE sensor 14 illustrated in FIG. 4 every 0.001 second, and obtains a frequency response output of the harmonic component illustrated in FIG. 5 based on the Fourier analysis result.

  FIG. 6 is an explanatory diagram illustrating an example of a relationship between a frequency response output in a specific frequency band related to the nonvolatile memory chip destruction process and a time change. FIG. 7 is an explanatory diagram showing an example of the relationship between the moving average value of the frequency response output in the specific frequency band related to the nonvolatile memory chip destruction process and the time change. In the figure, the dotted line is the frequency response output, and the solid line is the moving average value of the frequency response output. The acquisition unit 21 includes the frequency response of the eighth harmonic component in the vicinity of 224 kHz, which is a specific frequency band when the mold resin 2B and the silicon chip 2A are destroyed, among the frequency response outputs related to the destruction process of the nonvolatile memory chip shown in FIG. Extract the output. Furthermore, the acquisition unit 21 obtains the frequency response output (see FIG. 6) of the extracted harmonic component in the specific frequency band. Furthermore, the acquisition unit 21 performs the frequency response for 0.01 second of the harmonic component of the specific frequency band illustrated in FIG. 7 based on the frequency response output for 0.001 second for 0.01 seconds, that is, the latest 10 times. Get the moving average value for output.

  FIG. 8 is an explanatory diagram showing an example of a reference threshold setting method related to the nonvolatile memory chip destruction process. The setting unit 25 sets the moving average value related to the frequency response output of the harmonic component in the specific frequency band for 0.01 second from the start of destruction of the nonvolatile memory chip as the reference threshold value X. The setting unit 25 stores the reference threshold value X in the storage unit 26. The reference threshold value X is a moving average value related to the frequency response output of harmonic components in a specific frequency band for 0.01 seconds from the start of destruction of the nonvolatile memory chip, that is, the surface of the nonvolatile memory chip 2 by the horn 12. It is a moving average value related to the frequency response output of the harmonic component immediately after the start of destruction of the module resin 2B.

  FIG. 9 is an explanatory diagram showing a relationship among the reference threshold value X, the first threshold value, and the second threshold value related to the nonvolatile memory chip destruction process. Further, the setting unit 25 calculates the first threshold value X1 based on a first predetermined ratio of the reference threshold value X, for example, 50%, and sets the first threshold value X1 in the first determination unit 22. As shown in FIG. 9, the first threshold value X1 is a moving average value related to the frequency response output of harmonic components in a specific frequency band when the silicon chip 2A is broken by the horn 12. Further, the setting unit 25 calculates a second threshold value X2 based on a second predetermined ratio of the reference threshold value X, for example, 90%, and sets the second threshold value X2 in the second determination unit 23. As shown in FIG. 9, the second threshold value X2 is a moving average value related to the frequency response output of the harmonic component in the specific frequency band when the mold resin 2B is broken by the horn 12.

  The first determination unit 22 determines whether or not the moving average value related to the frequency response output of the harmonic component in the specific frequency band is equal to or less than the first threshold value X1. When the moving average value is equal to or less than the first threshold value X1, the first determination unit 22 completes the destruction of the mold resin 2B on the surface of the nonvolatile memory chip 2 based on a significant decrease in the moving average value. It is recognized that the destruction of the silicon chip 2A has started.

  The second determination unit 23 performs movement related to the frequency response output of the harmonic component in the specific frequency band after the moving average value related to the frequency response output of the harmonic component in the specific frequency band becomes equal to or less than the first threshold value X1. It is determined whether or not the average value is equal to or greater than the second threshold value X2. When the moving average value is equal to or greater than the second threshold value X2, the second determination unit 23 completes the destruction of the silicon chip 2A inside the nonvolatile memory chip 2 based on the significant increase of the moving average value again. Then, it is recognized that the destruction of the mold resin 2B on the back surface side of the nonvolatile memory chip has started.

  The control unit 24 controls the pulse oscillating unit 17 to stop the pulse output to the horn 12 when the moving average value related to the frequency response output of the harmonic component in the specific frequency band becomes equal to or greater than the second threshold value X2. . Further, the control unit 24 controls the stroke control unit 18 so as to raise the horn 12 in the stroke direction in order to retract the horn 12 from the surface of the nonvolatile memory chip 2.

  Next, operation | movement of the destruction apparatus 1 of a present Example is demonstrated. FIG. 10 is a flowchart showing an example of the processing operation of the process control unit 19 of the destruction apparatus 1 related to the nonvolatile memory chip destruction process. FIG. 11 is an explanatory diagram showing an example of the operation of the destruction device 1 related to the nonvolatile memory chip destruction processing. The nonvolatile memory chip destruction process shown in FIG. 10 is a process for reliably destroying the silicon chip 2A in a short time in the nonvolatile memory chip 2 by ultrasonic vibration.

  In FIG. 10, the process control unit 19 sets the high-pass filter to 100 kHz and the low-pass filter to 500 kHz as cut-off frequencies (step S11). The process control unit 19 sets the stroke speed of the horn 12 through the stroke control unit 18 (step S12). The control unit 24 of the process control unit 19 starts the pulse oscillation operation of the pulse oscillation unit 17 and the actuator drive operation of the stroke control unit 18 (step S13). 11A lowers the horn 12 onto the non-volatile memory chip 2 on the die 11. In the destruction device 1 shown in FIG. Then, the destruction device 1 shown in FIG. 11B transmits the ultrasonic vibration of the horn 12 to the surface of the nonvolatile memory chip 2 to destroy the module resin 2B and the silicon chip 2A on the surface of the nonvolatile memory chip 2 in this order. To do. At this time, the AE sensor 14 sequentially detects elastic waves generated at the time of destruction according to the destruction operation of the nonvolatile memory chip 2 due to ultrasonic vibration.

  The acquisition unit 21 of the process control unit 19 performs Fourier analysis every 0.001 seconds according to the detection output of the AE sensor 14 (step S14), and acquires the frequency response output shown in FIG. 5 from the detection output shown in FIG. . Furthermore, the acquisition part 21 determines whether the Fourier analysis result for 10 times was acquired (step S15). If the acquisition unit 21 has not acquired the Fourier analysis results for 10 times (No at Step S15), the acquisition unit 21 proceeds to Step S14 to acquire the next Fourier analysis result.

  Furthermore, when acquiring the Fourier analysis result for 10 times (Yes at Step S15), the acquisition unit 21 outputs the frequency response in the 224 kHz band among the 10 times of Fourier analysis results, that is, the 0.01 seconds of Fourier analysis results. To get. Further, when acquiring the frequency response output of the harmonic component in the 224 kHz band for 10 times, the acquiring unit 21 calculates a moving average value related to the frequency response output of the harmonic component in the 224 kHz band for 10 times (step S16). That is, the acquisition unit 21 acquires the frequency response output of the harmonic component in the 224 kHz band for 10 times, that is, the frequency response output for 0.01 seconds.

  When the setting unit 25 calculates the moving average value of the frequency response output of the harmonic component in the 224 kHz band for 10 times, the moving average value, that is, the moving average value for 0.01 second of the nonvolatile memory chip destruction start is set as the reference threshold value X. (Step S17). The setting unit 25 stores the reference threshold value X in the storage unit 26. The acquisition unit 21 performs a Fourier analysis every 0.001 seconds according to the detection output of the AE sensor 14 (step S18). The acquisition unit 21 calculates a moving average value of frequency response outputs of harmonic components in the 224 kHz band based on the latest 10 Fourier analysis results from the Fourier analysis (step S19).

  When the first determination unit 22 in the process control unit 19 calculates the moving average value related to the frequency response output of the harmonic component in the 224 kHz band for the last 10 times, the moving average value is 50% of the reference threshold value X, that is, the first It is determined whether or not the threshold value X1 is 1 or less (step S20). When the moving average value is equal to or smaller than the first threshold value X1 (Yes at Step S20), the second determination unit 23 in the process control unit 19 completes the destruction of the mold resin 2B on the surface side of the nonvolatile memory chip 2 It can be recognized that the destruction of the silicon chip 2A has started.

  The acquisition unit 21 responds to the detection output of the AE sensor 14 after the moving average value related to the frequency response output of the harmonic component of the 224 kHz band for the last 10 times becomes equal to or less than the first threshold value X1 (Yes in step S20). Fourier analysis is performed every 0.001 seconds (step S21). The acquisition unit 21 calculates the moving average value related to the frequency response output of the harmonic component in the 224 kHz band based on the latest 10 Fourier analysis results (step S22). Furthermore, when the second determination unit 23 calculates the moving average value related to the frequency response output for the latest 10 times, the moving average value related to the frequency response output for the latest 10 times is 90% of the reference threshold value X, that is, the second It is determined whether or not the threshold value is X2 or more (step S23).

  When the moving average value of the frequency response output for the latest 10 times is equal to or greater than the second threshold value X2 (Yes at Step S23), the control unit 24 completes the destruction of the silicon chip 2A by the ultrasonic vibration and completes the nonvolatile memory chip 2 It can be recognized that the destruction of the mold resin 2B on the back side has started. That is, the control unit 24 can recognize that the silicon chip 2A inside the nonvolatile memory chip 2 has been completely destroyed. Then, when the moving average value of the frequency response output for the latest 10 times is equal to or greater than the second threshold value X2 (Yes at Step S23), the control unit 24 determines that the pulse oscillation unit 17 and the stroke control unit stop the ultrasonic vibration. 18 is controlled (step S24), and the processing operation shown in FIG. The control unit 24 controls the pulse oscillating unit 17 so as to stop the output of the oscillation pulse to the ultrasonic transducer 12B. Further, as shown in FIG. 11C, the control unit 24 controls the stroke control unit 18 to raise the horn 12 in the stroke direction in order to retract the horn 12 from the surface of the nonvolatile memory chip 2. . As a result, the control unit 24 stops the ultrasonic vibration with respect to the nonvolatile memory chip 2.

  When the moving average value is not equal to or less than the first threshold value X1 (No at Step S20), the first determination unit 22 determines that the destruction operation of the mold resin 2B on the surface side of the nonvolatile memory chip 2 by the ultrasonic vibration is continued. The process proceeds to step S18 in order to obtain a Fourier analysis result of 0.001 seconds.

  If the moving average value is not equal to or greater than the second threshold value X2 (No at Step S23), the second determination unit 23 determines that the destruction operation of the silicon chip 2A inside the nonvolatile memory chip 2 due to ultrasonic vibration is continuing. Then, the process proceeds to step S21 in order to obtain a Fourier analysis result of 0.001 seconds.

  In the nonvolatile memory chip destruction process shown in FIG. 10, when the moving average value related to the frequency response output of the harmonic component in the specific frequency band is equal to or lower than the first threshold value X1, the surface side in the nonvolatile memory chip 2 is It can be recognized that the destruction of the mold resin 2B is completed and the destruction of the silicon chip 2A is started.

  Further, in the nonvolatile memory chip destruction process, after the moving average value related to the frequency response output of the harmonic component in the specific frequency band becomes equal to or lower than the first threshold value X1, the moving average value becomes equal to or higher than the second threshold value X2 again. In this case, it can be recognized that the destruction of the silicon chip 2A in the nonvolatile memory chip 2 has been completed.

  Further, in the nonvolatile memory chip destruction process, each time the nonvolatile memory chip 2 is destroyed, the moving average value related to the frequency response output of the harmonic component in the specific frequency band immediately after the nonvolatile memory chip destruction is started is set as the reference threshold value X. Therefore, even when the material component of the nonvolatile memory chip 2 is changed, it can be flexibly dealt with.

  In the destruction apparatus 1 of the present embodiment, after the moving average value related to the frequency response output of the harmonic component in the specific frequency band becomes equal to or less than the first threshold value X1, the moving average value becomes the second threshold value X2 or more again. Then, it is recognized that the destruction of the silicon chip 2A inside the nonvolatile memory chip 2 is completed by the ultrasonic vibration. And the destruction apparatus 1 stops ultrasonic vibration. As a result, in the destruction device 1 of the present embodiment, the silicon chip 2A can be reliably destroyed by punching the mold resin 2B and the silicon chip 2A on the surface side of the nonvolatile memory chip 2. Furthermore, in the destruction apparatus 1 of the present embodiment, it is not necessary to make a through hole in the nonvolatile memory chip 2 in order to destroy the silicon chip 2A, so that the work load required for the destruction can be reduced. Moreover, since the silicon chip 2A is physically destroyed, it is possible to leave evidence of the completion of the destruction, and it is possible to present and report the evidence to the client.

  Further, in this embodiment, even if the thickness of the mold resin 2B, the silicon chip 2A, etc. inside the nonvolatile memory chip 2 varies and the position of the silicon chip 2A inside the nonvolatile memory chip 2 varies, it takes a short time. The silicon chip 2A can be reliably destroyed.

  In this embodiment, the frequency response output of the harmonic component of the specific frequency band generated immediately after the start of destruction of the nonvolatile memory chip 2 is set as the reference threshold value X, and the first threshold value X1 is set to 50% of the reference threshold value X. And the first threshold value X1 is set in the first determination unit 22. Furthermore, in this embodiment, the second threshold value X2 is calculated with 90% of the reference threshold value X, and the second threshold value X2 is set in the second determination unit 23. As a result, since the reference threshold value X is set every time the nonvolatile memory chip 2 is destroyed, it is possible to flexibly cope with the destruction of the nonvolatile memory chips 2 made of different materials.

  In the present embodiment, the specific frequency band is a frequency band in which the difference between the frequency response outputs at the time of destruction of the mold resin 2B and the silicon chip 2A in the nonvolatile memory chip 2 due to ultrasonic vibration is maximized. As a result, the threshold determination operation of the first determination unit 22 and the second determination unit 23 is facilitated, and the determination accuracy can be improved.

  In the present embodiment, the threshold determination operation of the first determination unit 22 and the second determination unit 23 is performed using the moving average value of the frequency response output of the harmonic component in the specific frequency band. The influence of noise generated in the elastic wave can be suppressed.

  In the above embodiment, the first predetermined ratio for calculating the first threshold value X1 is 50%, but it may be about 40% to about 60%. Further, the first threshold value X1 is a moving average value related to the frequency response output of the harmonic component of the specific frequency band related to the destruction of the silicon chip 2A in the nonvolatile memory chip 2 without using the reference threshold value X. Also good.

  In the above embodiment, the second predetermined ratio for calculating the second threshold value X2 is 90%, but it may be about 80% to about 90%. Further, the second threshold value X2 is a moving average value related to the frequency response output of the harmonic component of a specific frequency band related to the destruction of the mold resin 2B in the nonvolatile memory chip 2 without using the reference threshold value X. Also good.

  Moreover, in the said Example, although 224 kHz was employ | adopted as a specific frequency band at the time of destruction of the mold resin 2B in the non-volatile memory chip 2 and the silicon chip 2A, it is not limited to this frequency band.

  In the above embodiment, each time the nonvolatile memory chip 2 is destroyed by ultrasonic vibration, the reference threshold value X is set. However, the material of the mold resin 2B and the silicon chip 2A of the nonvolatile memory chip 2 varies. If not, the reference threshold value X may be preset as a fixed value.

  In the above embodiment, the nonvolatile memory chip 2 in which the entire silicon chip 2A is sealed with the mold resin 2B has been described as an example. However, the present invention can be applied to an electronic component in which the silicon chip is sealed with the mold resin. Is possible. Moreover, in the said Example, although the specific numerical value was illustrated, it is not limited to these numerical values.

DESCRIPTION OF SYMBOLS 1 Destructive device 2 Non-volatile memory chip 2A Silicon chip 2B Mold resin 12 Horn 14 AE sensor 17 Pulse oscillator 18 Stroke control part 19 Process control part 21 Acquisition part 22 1st determination part 23 2nd determination part 24 Control part 25 Setting Unit 26 storage unit X reference threshold value X1 first threshold value X2 second threshold value

Claims (5)

An output unit that outputs ultrasonic vibrations that destroy the silicon chip sealed with the resin material;
A detection unit for detecting an elastic wave generated when the resin material or the silicon chip is destroyed by the ultrasonic vibration;
An acquisition unit that acquires a response output of a harmonic component in a specific frequency band in which the resin material and the silicon chip resonate, from the detected frequency response of the elastic wave;
The response output acquired by the acquisition unit is compared with a first threshold value that is a response output of a harmonic component of the specific frequency band generated when the silicon chip is broken by the ultrasonic vibration. A determination unit;
After the first determination unit determines that the response output of the harmonic component in the specific frequency band is equal to or less than the first threshold, the response output acquired by the acquisition unit and the ultrasonic vibration A second determination unit that compares and determines a second threshold value that is a response output of the harmonic component of the specific frequency band generated when the resin material is destroyed;
The second determination unit includes a control unit that stops the ultrasonic vibration of the output unit after determining that the response output of the harmonic component in the specific frequency band is equal to or greater than the second threshold. Destruction device characterized by.   A setting unit that calculates the first threshold value and the second threshold value from a reference threshold value of a response output of a harmonic component in the specific frequency band generated at the start of destruction of the resin material due to the ultrasonic vibration; The destruction apparatus according to claim 1. The specific frequency band is
Of the frequency band in which the resin material and the silicon chip resonate, a response output of a harmonic component related to the elastic wave generated when the resin material is destroyed by the ultrasonic vibration, and the silicon chip by the ultrasonic vibration The destruction device according to claim 1 or 2, wherein the destruction device has a frequency band in which a difference from a response output of a harmonic component related to the elastic wave generated at the time of destruction is maximized. The acquisition unit
The moving average value related to the response output of the extracted harmonic component of the specific frequency band is acquired as the response output of the harmonic component of the specific frequency band. Destruction device as described. A destruction method by a destruction device that destroys a silicon chip sealed with a resin material by ultrasonic vibration,
The destruction device is
Output ultrasonic vibration to the resin material or the silicon chip,
Detecting an elastic wave generated when the resin material or the silicon chip is broken by the ultrasonic vibration;
From the detected frequency response of the elastic wave, obtain a response output of a harmonic component of a specific frequency band in which the resin material and the silicon chip resonate,
Comparing and determining the acquired response output of the harmonic component in the specific frequency band and the first threshold value that is the response output of the harmonic component in the specific frequency band generated when the silicon chip is broken by the ultrasonic vibration And
After the response output of the harmonic component of the specific frequency band becomes equal to or lower than the first threshold, the response output of the harmonic component of the specific frequency band and the specific that occurs at the time of destruction of the resin material due to the ultrasonic vibration Compare and determine the second threshold that is the response output of the harmonic component of the frequency band,
A destruction method, comprising: causing each process to stop the output of the ultrasonic vibration when a response output of a harmonic component in the specific frequency band is equal to or greater than the second threshold value.

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