JP5221314B2 - Ultrasonic measurement method and electronic component manufacturing method - Google Patents

Description

The present invention, ultrasonic measurement methods, and, which relates to an electronic component manufacturing how, in particular, ultrasonic measuring method for performing the measurement object more surfactants in the ultrasonic irradiation directions cross and super those related is measured by ultrasonic measuring method good evaluation electronic component to the electronic component manufacturing how to manufacture a product.

  2. Description of the Related Art Conventionally, as an apparatus for measuring the inside of an object, there is an ultrasonic measuring apparatus that uses an ultrasonic wave that has been transmitted and reflected inside the object (for example, see Patent Document 1 and Patent Document 2). ).

  As a conventional ultrasonic measurement apparatus, an ultrasonic measurement apparatus that performs measurement inside a semiconductor package will be described.

  FIG. 11 is a schematic configuration diagram of a conventional ultrasonic measurement method. In order to clarify the relative positional relationship between the drawings, XYZ axes are displayed in the drawings.

  In FIG. 11, an ultrasonic measurement apparatus 1 includes an ultrasonic probe 2 for receiving and transmitting ultrasonic waves, an input unit 3 for inputting ultrasonic measurement conditions such as the frequency of ultrasonic waves to be transmitted, A control unit 4 for processing information obtained from the acoustic probe 2 and the input unit 3 to control the operation of the ultrasonic probe 2, and a display unit for displaying measurement results such as an ultrasonic waveform 5.

  The operation of the ultrasonic measurement apparatus 1 will be briefly described.

  The ultrasonic wave transmitted while controlling the movement of the ultrasonic probe 2 by the control unit 4 based on the measurement conditions input by the input unit 3 is applied to the semiconductor package 7 using the water 6 in the container as a medium. The Then, the reflected wave reflected by the semiconductor package 7 as the measurement object is received by the ultrasonic probe 2. The control unit 4 processes the received reflected wave to determine whether the semiconductor package 7 is good or bad, and displays the result on the display unit 5.

  Here, the ultrasonic probe 2 is used for both receiving and transmitting purposes. Further, the control unit 4 includes a pulser receiver that converts the reflected wave received by the ultrasonic probe 2 into a voltage and amplifies it, and an image processing unit that images the intensity value of the voltage waveform.

  The semiconductor package 7 is a package having a multilayer structure with respect to the ultrasonic wave irradiation direction (Z-axis direction in FIG. 11) and having a plurality of interfaces.

  In order to describe the conventional ultrasonic measurement in more detail, the vicinity of the measurement unit in FIG. 11 is enlarged and described together with the structure of the semiconductor package 7.

  FIG. 12 is a schematic diagram of conventional ultrasonic measurement.

  In FIG. 12, a semiconductor package 7 includes a substrate 8 having a substrate-side electrode on the upper surface, solder 9 as an example of a bonding material provided on each substrate-side electrode of the substrate 8, and a substrate-side electrode of the substrate 8 by the solder 9. The interposer 10 has an interposer-side electrode joined to the semiconductor chip 11, a semiconductor chip 11, lead wires 12 that connect the interposer 10 and the semiconductor chip 11, and a resin mold 13 that covers the semiconductor chip 11.

  As shown in FIG. 12, here, an example of the semiconductor package 7 being submerged is shown. In the semiconductor package 7, which is a specific example of the measurement object placed in the liquid (water) 6, the water 6 A plurality of interfaces such as an interface between the resin mold 13 and the resin mold 13, an interface between the resin mold 13 and the interposer 10, and an interface between the interposer 10 and the solder 11 are formed.

  With this configuration, when the ultrasonic wave from the ultrasonic probe 2 is irradiated onto the semiconductor package 7, when the reflected wave reflected by the semiconductor package 7 is received by the ultrasonic probe 2, the signal is a plurality of signals. Waves overlap each other. This waveform will be described.

  When the semiconductor package 7 having a plurality of interfaces as shown in FIG. 12 is subjected to ultrasonic measurement, the waveform shown in FIG. 13 is obtained.

  FIG. 13 is a diagram showing an ultrasonic waveform in the conventional ultrasonic measurement. A method for determining pass / fail of a measurement location using this waveform will be described.

  As shown in FIG. 13, when a semiconductor package 7 having a plurality of interfaces inside is measured, it is difficult to define a measurement location (interface) because a plurality of waves overlap each other.

  Therefore, a measurement location (interface) is defined by using a time delay (phase shift) from the surface of the semiconductor package 7 where the ultrasonic waveform is stably generated as a reference.

In FIG. 13, first, a trigger 14 (time t ₀ ) on the time axis is provided for a surface wave from the surface of the semiconductor package 7. Subsequently, based on the internal configuration of the semiconductor package 7, a time region called a gate 15 (time t ₁ ) with the trigger 14 as a zero base point is set for the reflected wave at the measurement location. Then, the measurement location is evaluated by comparing with a threshold value in the section (time region) of the gate 15.
JP 05-333007 A Japanese Patent Application Laid-Open No. 06-294779

  However, this method has a problem in that the measurement accuracy is lowered when two semiconductor packages of the same type are continuously subjected to ultrasonic measurement. This problem will be described.

  FIG. 14 is a diagram illustrating a waveform of an ultrasonic wave reflected by conventional ultrasonic measurement.

  When two semiconductor packages of the same type are continuously subjected to ultrasonic measurement, the waveform shown in FIG. 14 is obtained. As shown in FIG. 14, the reflected waves in the two semiconductor packages are reflected waves 16 in the first semiconductor package, and reflected waves 17 in the second semiconductor package, respectively. Obtained in a shifted state.

In the conventional ultrasonic measurement, the measurement location of the reflected wave 17 is evaluated using the trigger 18 (time t ₂ ) and the gate 19 (time t ₃ ) that are initially set based on the reflected wave 16. Therefore, as shown in FIG. 14, the gate 19 (time t ₃ ) is greatly deviated from the actual measurement location (time t ₄ ) of the reflected wave 17.
Accordingly, an object of the present invention is to solve the above-described problem, and a highly accurate ultrasonic measurement method and electronic component manufacturing even for a measurement object in which a plurality of interfaces intersect in the ultrasonic irradiation direction. It is to provide a mETHODS.

Also to the object of measurement in which a plurality of surface ultrasonic irradiation directions cross, accurate ultrasonic measurement methods, and, in order to provide an electronic component manufacturing how, the present invention is constructed as follows.

According to the first aspect of the present invention, the ultrasonic probe receives the ultrasonic waveform signals respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
The measurement object is an electronic component, and the measurement object interface is an electrode bonding portion where electrodes are bonded to each other with a bonding material inside the electronic component or a portion adjacent to the electrode bonding portion, and the measurement target. After measuring the interface at the computing unit, to provide an ultrasonic measuring how to evaluate the bonding state of the electrode junction at the measurement target surface by the arithmetic unit.

According to the second aspect of the present invention, the ultrasonic probe receives the ultrasonic waveform signals respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
Wherein when detecting the waveform signal, the reference interface, to provide an ultrasonic measuring method Ru interface der having a maximum amplitude intensity among the plurality of interfaces in the object to be measured.

According to the third aspect of the present invention, the ultrasonic probe receives the waveform signals of the ultrasonic waves respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
Wherein when detecting the waveform signal, the reference interface, to provide an ultrasonic measuring method Ru surface der of buried objects embedded in the measurement target.

According to the fourth aspect of the present invention, the ultrasonic probe receives the waveform signals of the ultrasonic waves respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When the waveform signal is detected, the object to be measured is a semiconductor package, and the reference interface is an electrode bonding portion where the electrodes are bonded to each other by the bonding material inside the semiconductor package or the electrode bonding a adjacent portions in section, and to provide an ultrasonic measuring how to position the interface of two layers of different materials.

According to the fifth aspect of the present invention, the ultrasonic probe receives the waveform signals of the ultrasonic waves respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When receiving the ultrasonic waveform signal, the ultrasonic wave transmitted from the ultrasonic probe receives the ultrasonic waveform signal reflected by a plurality of interfaces of the measurement object,
Furthermore, after detecting the waveform signal at the reference interface and before measuring the measurement target interface by the calculation unit, based on the waveform signal received while bringing the ultrasonic probe and the measurement target close to each other It said to provide an ultrasonic measuring how to adjust the position of the ultrasonic probe Te.

According to the sixth aspect of the present invention, the ultrasonic probe receives the waveform signals of the ultrasonic waves respectively reflected at the plurality of interfaces in the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When the measurement target interface is measured by the calculation unit, a waveform signal detected after the waveform signal of the reflected wave at the reference interface is previously determined based on the waveform signal of the reflected wave at the reference interface. compared to input non-defective waveform signal, the comparison result by providing a row cormorants ultrasonic measuring method to evaluate the measurement target surface.

According to the seventh aspect of the present invention, the ultrasonic probe receives the waveform signals of the ultrasonic waves respectively reflected at the plurality of interfaces in the electronic component,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the electronic component is detected by the arithmetic unit,
Perform measurement by measuring the measurement target interface of the electronic component identified by using the waveform signal of the reflected wave at the reference interface as a starting point ,
Provided is an electronic component manufacturing method using the electronic component evaluated as a good product as a product.

  As described above, according to the present invention, it is possible to significantly reduce the influence of a time delay shift or the like on a measurement object in which a plurality of interfaces intersect in the ultrasonic irradiation direction, with high accuracy. Ultrasonic measurement can be performed.

  Before continuing the description of the present invention, the same parts are denoted by the same reference numerals in the accompanying drawings.

  Embodiments of the present invention will be described below with reference to the drawings. As an ultrasonic measurement apparatus and method of the present invention, an ultrasonic measurement apparatus and method for measuring the inside of an electronic component that is a measurement object, for example, a semiconductor package, will be described.

(Embodiment 1)
FIG. 1A is a schematic configuration diagram of an ultrasonic measurement apparatus for performing the ultrasonic measurement method according to Embodiment 1 of the present invention.

  In FIG. 1A, an ultrasonic measurement apparatus 20 includes an ultrasonic probe 21 for receiving and transmitting ultrasonic waves, and an ultrasonic probe that drives the ultrasonic probe 21 independently in the XYZ axis directions orthogonal to each other. The probe driving unit 21a, the input unit 22 for inputting ultrasonic measurement conditions, the ultrasonic probe 21 and the information obtained from the input unit 22 are processed to control the operation of the ultrasonic probe 21. And a display unit 24 as an example of an output unit for displaying measurement results such as ultrasonic waveforms.

  The operation of the ultrasonic measurement apparatus 20 will be briefly described.

  The lower end of the ultrasonic probe 21 is arranged in the water 25 in the water tank 25a, and the semiconductor package 26 as an example of the measurement object is located at a predetermined measurement object arrangement position in the water 25 in the water tank 25a. Has been placed. Then, for example, ultrasonic waves in a frequency band of about 10 to 100 MHz are irradiated onto the semiconductor package 26 using the water 25 as a medium, and reflected waves respectively reflected at a plurality of interfaces in the semiconductor package 26 can be received.

  Here, in FIG. 1A, the directions parallel to the bottom surface of the water tank 25a and orthogonal to each other are defined as the X direction and the Y direction, and the directions orthogonal to these planes are defined as the Z direction.

  The ultrasonic probe driving unit 21a is configured by, for example, an XYZ robot that moves the ultrasonic probe 21 in the X direction, the Y direction, and the Z direction, respectively. The ultrasonic probe 21, the ultrasonic probe drive unit 21a, a transmission circuit 70 described later, and a reception circuit 71 described later constitute an example of an ultrasonic transmission / reception apparatus.

  An ultrasonic probe 21, an input unit 22, and a display unit 24 are connected to the control unit 23.

  The input unit 22 uses a keyboard, a mouse, a touch panel, or various input devices such as voice input, so that an operator inputs information necessary for ultrasonic measurement such as numerical values, or a CAD of the semiconductor package 26. Data (including, for example, the material of each layer, thickness, dimension of each side, acoustic impedance, position of the semiconductor chip, position of the joint, etc. of the semiconductor package or substrate) and position coordinates of the position of the semiconductor package 26 in the water tank It is a device for inputting information necessary for ultrasonic measurement, such as data and ultrasonic irradiation conditions (bore diameter, focal length, power, etc.). The input unit 22 is further stored in the measurement position data memory 77, the determination unit 75, the master data holding memory 76 (and a reference interface determination unit 80, which will be described later), or another server or recording medium. It has a connection terminal for the database. As an example, measurement conditions are input from the input unit 22 and stored in the measurement position data memory 77, the determination unit 75, and the master data holding memory 76, respectively. That is, information necessary for the drive control unit 78 is input from the input unit 22 and stored in the measurement position data memory 77. Information required for the determination unit 75 is input from the input unit 22 and stored in the internal memory of the determination unit 75. In the master data holding memory 76, information necessary for the data calculation unit 74 is input from the input unit 22 and stored. Examples of measurement conditions include a scanning area, a scanning pitch, a trigger position, a trigger width, a gate position, and a gate width. As a scanning area of the ultrasonic probe 21 (measured portion, that is, a portion to be measured), a range to be measured of the semiconductor package 26 is set (in other words, an XY plane position and a Z position are set). . For example, the scanning area may be the entire surface of the semiconductor package 26, a part of the semiconductor package 26, or a plurality of areas in the semiconductor package 26. The scanning pitch means mechanical resolution (XY plane) for acquiring reflected wave waveform data (waveform signal). As one example, data can be acquired at a pitch of several μm to 100 μm, but is not limited thereto. The trigger position, trigger width, gate position, and gate width are related to a signal for specifying the reference position of the measurement time signal (trigger signal) and a measurement start position signal (gate signal) having a time offset from the reference signal. is there. The setting of the trigger position is important in the first embodiment. As will be described in detail later, for example, a characteristic location inside the semiconductor package 26 (an electrode junction or a portion near the electrode junction and an acoustic impedance difference) Interface between large material layers). The trigger width is set to about the wavelength of the ultrasonic probe to be used. For example, in the case of an ultrasonic probe capable of transmitting a 100 MHz ultrasonic wave, if one wavelength is 10 ns and the actual wave number of the ultrasonic wave emitted from the ultrasonic probe is 1.5 wavelengths, the trigger width May be 15 ns. As the setting of the gate position, it is conceivable that the gate position is set by the data calculation unit 74 as an example of the calculation unit from master data created in advance. The gate width is normally set by the data calculation unit 74 to the reflected wave width in the time zone of interest, and in many cases, the data calculation unit 74 sets the length to one cycle of the sine wave or less. The frequency band of the ultrasonic wave used for the semiconductor package 26 is between about 10 to 100 MHz, and therefore the gate width is often set by the data calculation unit 74 to 10 to 100 ns. When the information of the interface to be measured is unknown, a plurality of gate numbers are set for comparison with other gate information. As described later, the pass / fail judgment of the measured portion (for example, the electrode joint portion) of the semiconductor package 26 is performed mainly by the waveform intensity value within the gate section thus set. As an example of the pass / fail judgment method, use the maximum and minimum values (negative maximum value) of the waveform intensity in the gate section, or the maximum value of the absolute value, and these values and the bonding state are good. It is possible to determine whether the product is good or bad by comparing with a threshold value indicating that As a specific example of the pass / fail determination method, an OK / NG (pass / fail) determination value is set in advance and used as a threshold value. As an example, in FIGS. 15A and 15B, the threshold value is set to 100, and when the maximum value exceeds the threshold value, OK (non-defective product determination) is set, and when the maximum value falls below the threshold value, NG (defective product determination) is set. The method of determining the threshold is determined while measuring the actual defective product.

  As an example, in the previous stage of performing the following measurement steps (the stage before the start of measurement), information on the waveform master data conditions (measurement start time position, time width, etc.) is input from the input unit 22 to hold the master data. By storing the data in the memory 76, waveform master data is created in advance in the master data holding memory 76. In consideration of the accuracy of sound speed and / or the variation in thickness of each layer, the master data needs to have a certain time width. As an example, it is 15 ns. The time width of the master data is determined by the frequency band of the ultrasonic probe to be used. For example, the length of one wavelength (10 ns) in a certain frequency band (for example, 100 MHz) is determined, and further, the set time width (15 ns) is determined by the wave number (1.5 wavelengths) of the actually emitted ultrasonic wave. It is better to decide.

  The display unit 24 includes a display as an example, and displays a determination result imaged after performing a predetermined calculation and determination based on information received by a data processing unit 73 described later of the control unit 23. To do.

  The control unit 23 is connected to the ultrasonic probe 21 and transmits an ultrasonic wave, and converts the ultrasonic wave connected to the ultrasonic probe 21 and received by the ultrasonic probe 21 into a voltage. The pulsar receiver (receiver circuit) 71 to be amplified, the A / D circuit 72 connected to the receiver circuit 71 for converting the received reflected wave signal into digital information, and the digital information from the A / D circuit 72 And a data processing unit 73 that performs predetermined data processing (for example, imaging of intensity values of measurement waveforms). The control unit 23 is further connected to the measurement position data memory 77, the ultrasonic probe driving unit 21a, and the measurement position data memory 77, and is based on information stored in the measurement position data memory 77. And a drive control unit 78 that controls the child drive unit 21a.

  The data processing unit 73 includes a master data holding memory 76 as an example of a reference signal storage unit that stores in advance master data serving as a reference signal of the waveform signal of the ultrasonic reflected wave, the master data holding memory 76, and the A / D circuit 72. And a data calculation unit 74 as an example of a calculation unit that performs calculation based on information stored in the master data holding memory 76 and digital information from the A / D circuit 72, and connected to the data calculation unit 74. And a determination unit 75 that performs a pass / fail determination operation based on the calculation result of the data calculation unit 74.

  The ultrasonic probe 21 is controlled while controlling the movement of the ultrasonic probe 21 under the drive control by the transmission circuit 70 and the drive control unit 78 of the control unit 23 based on the measurement condition input by the input unit 22. The ultrasonic waves transmitted from the semiconductor package 26 are irradiated with the water 25 as a medium. Then, the reflected wave reflected by the semiconductor package 26 as the measurement object is received by the ultrasonic probe 21. The control unit 23 processes the received reflected wave to determine whether the semiconductor package 26 is good or bad, and display the result on the display unit 24. That is, based on the received information, the reception circuit 71 of the control unit 23 converts the ultrasonic reception signal into voltage and amplifies it, converts it to digital information by the A / D circuit 72, and then the data calculation unit of the data processing unit 73. 74. The data processing unit 74 performs waveform processing, image processing, and the like, so that the determination unit 75 determines the quality of the interface of the semiconductor package 26 and images the determination result. The imaged determination result is displayed on a display as an example of the display unit 24.

  Here, the ultrasonic probe 21 uses a single ultrasonic probe for both receiving and transmitting purposes, thereby simplifying the overall structure.

  The semiconductor package 26 has a multilayer structure with respect to the ultrasonic wave irradiation direction (Z-axis direction in the figure) and has a plurality of interfaces, and a waveform signal of a reflected wave generated by the ultrasonic wave irradiation. It is an object to be measured (measuring object) whose bonding state of the boundary surfaces of the plurality of interfaces is measured by detection.

  A specific multilayer structure of the semiconductor package 26 is the structure shown in FIG. The ultrasonic waves are also transmitted inside the semiconductor package 26, and a reflected wave is generated from the internal interface. Therefore, the reflected wave signal received by the ultrasonic probe 21 is a waveform signal in which a plurality of waves generated from a plurality of interfaces are overlapped.

  In order to describe the ultrasonic measurement according to the first embodiment in more detail, the vicinity of the part to be measured (part to be measured) in FIG. 1A is enlarged and described together with the structure of the semiconductor package 26.

  In FIG. 2, the semiconductor package 26 is provided, for example, on a substrate 27, a substrate-side pad 28 provided on the upper surface of the substrate 27, an interposer 29 bonded to the substrate 27, and a lower surface of the interposer 29. The interposer side pad 30, the solder 31 as an example of a bonding material for bonding the substrate side pad 28 and the interposer side pad 30, and the interposer 29 and the flip chip connection (not shown) are directly connected. A semiconductor chip 32 and a resin mold 33 covering the semiconductor chip 32 are included.

  Such a semiconductor package 26 is manufactured as follows.

  First, the semiconductor chip 32 is connected to the upper surface of the interposer 29 having a large number of interposer-side pads 30 on the lower surface by flip chip connection or the like.

  Next, the resin chip 33 is formed by covering the semiconductor chip 32 on the interposer 29 with an insulating synthetic resin.

  Thereafter, solder 31 is formed on each interposer side pad 30 of the interposer 29 or each substrate side pad 28 of the substrate 27.

  Next, each interposer side pad 30 of the interposer 29 and each substrate side pad 28 of the substrate 27 are connected via the solder 31.

  By manufacturing in this way, an interface that can function as a reference interface (a reference surface for determining whether or not a joint is good) is created at the time of manufacturing. That is, the reference interface that can be reflected during ultrasonic irradiation to acquire an ultrasonic waveform signal is formed between the electrodes (the board-side pad 28 and the interposer-side pad 30) between the solder 31 inside the semiconductor package 26. The electrode bonding portion to be bonded or a portion adjacent to the electrode bonding portion is positioned at the interface between two layers of different materials. Specifically, as an example, the interposer 29 and the interposer side pad 30 are set so that the acoustic impedance difference between the interposer 29 and the interposer side pad 30 is the largest compared to the acoustic impedance difference between the other two layers. Select and use each material. As a more specific example, as will be described later, an epoxy resin may be used as the material of the interposer 29 and copper may be used as the material of the interposer side pad 30.

The material of the substrate 27 is an epoxy resin, the material of the substrate side pad 28 and the material of the interposer side pad 30 are copper (Cu), and the material of the interposer 29 is an epoxy resin. The material of the solder 31 is a solder alloy such as Sn / Pb / Cu or Sn / Pb / Ag and a lead-free solder such as Sn / Ag / Cu or Sn / Cu. The material of the semiconductor chip 32 is Si, and the material of the resin mold 33 is a mixture of an epoxy resin and a filler (SiO ₂ ). As an example of the semiconductor package 26 in the first embodiment, a CSP package having the same package size and silicon size is used.

  Further, the thickness of the substrate 27 is several hundred μm, and the internal sound velocity is 2,500 m / s. The thicknesses of the substrate-side pad 28 and the interposer-side pad 30 are several tens of μm, and the internal sound velocity is 4,700 m / s. The thickness of the interposer 29 is 100 to 300 μm, and the internal sound velocity is 2,500 m / s. The solder 31 has a thickness of 100 μm and an internal sound velocity of 3,200 m / s. The thickness of the semiconductor chip 32 is 200 to 300 μm, and the internal sound velocity is 8,500 m / s. The thickness of the resin mold 33 is 400 to 700 μm, and the internal sound velocity is 3,930 m / s. Note that the sound velocity value of the ultrasonic wave varies depending on the temperature of the object to be measured. Therefore, in the first embodiment, it is assumed that the temperature satisfying the sound velocity value is kept constant. Further, the temperature of the object to be measured is measured using a temperature measuring unit (not shown) and the sound speed is corrected, so that the accuracy can be increased.

  As shown in FIG. 2, a plurality of interfaces such as an interface between the water 25 and the resin mold 33, an interface between the resin mold 33 and the interposer 29, and an interface between the interposer side pad 30 and the solder 31 are formed.

  The ultrasonic measurement using the configuration described above will be described.

  In the semiconductor package 26 as in the first embodiment, when the method using the surface of the resin mold 33 as a trigger as used conventionally, the influence of variations in time delay (phase shift) becomes large. Therefore, first, the trigger (reference signal or reference interface) is set by the data calculation unit 74 (or the reference interface determination unit 80 and the data calculation unit 74) other than the surface of the resin mold 33.

  Here, the position of the interface as a trigger (reference signal) first exists on the ultrasonic probe 21 side from the joint portion between the solder 31 as the final measurement target and the substrate-side pad 28 of the substrate 27. There is a need. This is because the part to be measured (joint part between the solder 31 and the board-side pad 28 of the board 27) is measured based on the time delay (phase shift) from the trigger, and therefore the trigger is made before this part to be measured. This is because it is necessary to be measured.

  First, a trigger setting method will be described. Actually, this trigger setting method is performed, for example, in step S2 described later.

The trigger needs to have a greater signal strength than the surrounding waveform because of its use. In order for the ultrasonic reflected waveform to have a large intensity (amplitude intensity), the difference in acoustic impedance between the two materials at the interface needs to be large. If the acoustic impedance between the two materials is Z ₁ and Z ₂ respectively, the sound pressure reflectance R is
R = (Z ₂ −Z ₁ ) / (Z ₂ + Z ₁ )
It is represented by From this relationship, it is necessary to use a reflected wave at the interface between the material layers having a large acoustic impedance difference as a trigger.

  As a result of various investigations by the present inventors, in the first embodiment, an epoxy resin is used as the material of the interposer 29 and copper is used as the material of the interposer side pad 30. Therefore, the respective acoustic impedances are epoxy resin: 2.9 to 3.6 and copper: 45.8 (hereinafter, the unit of impedance is 10 kg / ms). In the configuration of the first embodiment, the acoustic impedance difference between these two layers (between the interposer 29 and the interposer side pad 30) is the largest compared with the acoustic impedance difference between the other two layers. This signal is used as a trigger. Further, in order to increase the accuracy, the acoustic interface difference between the two layers is simply not compared with the acoustic impedance difference between the other two layers as the reference interface. You may define An interface having an acoustic impedance difference between the two layers larger than a predetermined threshold and an area larger than the diameter of the irradiated ultrasonic wave, in the vicinity of the joint, that is, the interposer side pad 30 or the substrate side pad An interface located near 28 may be defined as a reference interface. If the difference in acoustic impedance is not larger than the predetermined threshold value, a reference interface may be formed in advance by applying Embodiment 2 or Embodiment 3 described later. As conditions for setting the reference interface, for example, the acoustic impedance of the epoxy resin is 2.9 to 3.6, and the acoustic impedance of the metal (Cu, Ag, etc.) used for the reference interface is about 20 to 50. Therefore, an interface having an impedance difference of 10 or more may be used as the reference interface.

  In addition, as a means for setting such a reference interface, a reference interface determination unit 80 is provided in the control unit 23 (see FIG. 1B), and the acoustic impedance difference between the two layers is calculated and compared with each other, which is the largest. The interface may be determined as the reference interface. Alternatively, the reference interface determination unit 80 determines the presence or absence of a reference interface formed in advance. If there is a reference interface, the reference interface is used. The acoustic impedance difference may be calculated and compared with each other, and the largest interface may be determined as the reference interface. The result information determined by the reference interface determination unit 80 may be output and stored in the measurement position data memory 77, the determination unit 75, and the master data holding memory 76, respectively.

  FIG. 3 is a diagram illustrating an ultrasonic waveform in the ultrasonic measurement according to the first embodiment, in which the horizontal axis is time and the vertical axis is amplitude.

In FIG. 3, a signal at the interface between the interposer 29 and the interposer-side pad 30 is used as a trigger 34 (time t ₅ ), and the position of the gate 35 (time t ₆ ), which is a signal at the measurement target, is used as a data calculation unit. Specify 74. In the first embodiment, the data calculation unit 74 calculates the generation time from the thickness and sound speed of each component, and the data calculation unit 74 calculates the generation time. As a result, the solder 31 and the substrate 27 are formed after 31 nsec from the generation of the trigger 34. It can be seen that the waveform of the signal (gate 35) at the interface with the side pad 28 is generated.

  As a method of evaluating the waveform intensity at the gate 35, the time difference (phase difference) between the trigger 34 (reference interface) and the gate 35 (measurement target interface) obtained by the data calculation unit 74 from the configuration in the semiconductor package 26 in this way. ) Is used to specify the position of the gate 35 by the data calculation unit 74, and the threshold value input in advance from the input unit 22 is compared with the amplitude intensity of the waveform signal at this position by the data calculation unit 74. For example, a method in which the determination unit 75 evaluates (determines) the quality of the bonding surface) is used. That is, when the amplitude intensity of the waveform signal is smaller than the threshold value, the determination unit 75 determines that the waveform signal is defective. In addition, when the amplitude intensity of the waveform signal is greater than or equal to the threshold value, the determination unit 75 determines that the waveform signal is good.

  Subsequently, another evaluation method other than the above-described evaluation method by comparison with a threshold value will be described.

  FIG. 4A is a diagram showing the waveform strength evaluation of the gate position in the ultrasonic measurement of the first embodiment, and FIG. 4B is a diagram of master data in the ultrasonic measurement of the first embodiment. FIG. 4C is a diagram showing a correlation coefficient value in the ultrasonic measurement according to the first embodiment.

  In the waveform evaluation method in the first embodiment, the waveform of the joint portion between the solder 31 and the substrate side pad 28 of the substrate 27, which are known to be non-defective, is cut out by the data calculation unit 74, and master data holding memory is used as master data. A method is used in which the data calculation unit 74 evaluates a correlation function (correlation coefficient value) between the master data and actual measurement data (digital information from the A / D circuit 72).

  First, in the data calculation unit 74, the time position of the trigger 34 is set to the start point T = 1. Hereinafter, the measurement operation interface of the semiconductor package 26 specified by using the waveform signal at the trigger 34 (reference interface) as a starting point is measured by the data calculation unit 74 in the following procedure.

  Subsequently, as shown in FIG. 4B, the data calculation unit 74 performs data calculation on the correlation coefficient data string with the measurement data while shifting the master data in the time axis direction (right side in FIG. 4). Created in part 74.

  Next, the data calculation unit 74 combines the measurement data and the start point (T = 1) of the master data to obtain a correlation coefficient value.

  Next, in the data calculation unit 74, the correlation coefficient value is obtained by matching the starting point of the master data with T = 2, that is, the second point of the measured waveform. This is continued until T = N− (n + 1) in the data calculation unit 74, where N is the length of the measurement data from the trigger 34 and n is the length of one cycle of the master data (where N> n). Then, the correlation coefficient is calculated at each T, and the correlation coefficient data string shown in (c) of FIG.

  FIG. 5 is a diagram showing a correlation coefficient data string of the ultrasonic measurement according to the first embodiment, showing in detail (c) of FIG.

In FIG. 5, the horizontal axis represents time T, and the vertical axis represents the correlation coefficient value. In the data calculation unit 74, the correlation coefficient value when the junction waveform of the master data and the measurement data coincides is set as the maximum value point 36 (time t ₇ ) of the correlation coefficient data string, and the correlation at the maximum value point 36 is obtained. A numerical value is used as an evaluation value.

  If the bonding portion between the solder 31 and the substrate-side pad 28 of the substrate 27 is in a normal bonding state, the measurement data has a waveform close to that of the master data, so the correlation coefficient value is close to 1. On the contrary, when the bonding state between the solder 31 and the board-side pad 28 of the board 27 is not good and cracks or voids are generated, the correlation coefficient value is smaller than 1.

  In the determination method using such a correlation coefficient, conventionally, it is necessary to shift the master data in the time axis direction with respect to the entire measurement data. There was a problem of recognition. However, as in the first embodiment, by providing a trigger in the data calculation unit 74 and performing correlation coefficient processing from the position in the data calculation unit 74, the calculation time is reduced and the possibility of erroneous recognition is reduced. The effect is obtained.

  In this way, not the surface of the semiconductor package 26, but the characteristic part inside the semiconductor package 26 (the electrode junction or the interface near the electrode junction and the interface between the substance layers having a large acoustic impedance difference) is used as the data calculation unit 74. (Or the reference interface determination unit 80 and the data calculation unit 74) is set as the trigger 34, and the gate 35 is set by the data calculation unit 74 (or the reference interface determination unit 80 and the data calculation unit 74) based on the trigger 34. Inspection (measurement) is performed by the data operation unit 74. As a result, even when the position of the interface between the solder 31 and the substrate-side pad 28 of the substrate 27 is not stabilized due to the variation caused by the thickness tolerance of the interposer 29 or the like, the measurement of the portion to be measured can be performed only after the trigger position. Inspection (measurement) can be performed by the data calculation unit 74, and ultrasonic measurement with high accuracy is possible.

  Specifically, since a semiconductor package 26 in which a plurality of joints, ie, electrode points, in which the substrate side pads 28 and the interposer side pads 30 are joined by solder 31 is used as a measurement object, triggers are respectively set at the respective electrode points. Is detected by the data calculation unit 74, the waveform determination of the solder joint is performed by the data calculation unit 74, and the determination unit 75 determines pass / fail.

  As described above, according to the present invention, it is possible to significantly reduce the influence of a time delay shift or the like on a measurement object in which a plurality of interfaces intersect in the ultrasonic irradiation direction, with high accuracy. Ultrasonic measurement can be performed. Here, as indicated by the alternate long and short dash line G in FIG. 2, when the ultrasonic wave passes through the path from the resin mold 33 to the solder 31 through the interposer 29, it passes through a total of three types of layers. When the reference interface exists in the electrode part, the resin mold 33 and the interposer 29 are not interposed between the reference interface and the electrode part, and the interface between the medium such as the water 25 and the resin mold 33 and the resin mold 33 and the interposer 29. Since the influence of the interface with is ignored, it is possible to greatly reduce the influence of the time delay shift.

  The flow of the first embodiment when using a method other than the comparison with the master data in order from the reference interface will be described with reference to FIG.

  FIG. 6 is a diagram showing a flow of ultrasonic measurement according to the first embodiment.

  In FIG. 6, first, in step S <b> 1, an ultrasonic wave is transmitted from the ultrasonic probe 21 to the measurement object (in the first embodiment, the semiconductor package 26), and reflected waves reflected at the respective interfaces of the measurement object. Is received by the ultrasonic probe 21.

  Subsequently, in step S2, the trigger (time correction trigger) 34 is set as data based on the waveforms of the plurality of reflected waves received by the ultrasonic probe 21 and the interface information based on the configuration of each layer of the measurement object. Setting is performed by the calculation unit 74 (or the reference interface determination unit 80 and the data calculation unit 74).

  Subsequently, in step S3, the time difference (phase difference) between the trigger 34 and the part to be measured (the joint part between the solder 31 and the substrate 27 in the first embodiment) based on the thickness and sound velocity of each component of the measurement object. ) Is detected by the data calculation unit 74.

  Subsequently, in step S <b> 4, the position (measurement location) of the gate 35 is set by the data calculation unit 74 based on the trigger 34 obtained by the data calculation unit 74 and the time difference (phase difference) based on the configuration of each layer.

  Subsequently, in step S5, based on the correlation coefficient between the measurement data and the master data obtained in order from the trigger 34, the waveform of the reflected wave at the position of the gate 35 is evaluated by the data calculation unit 74, and the measured portion The determination unit 75 determines whether the joining state is good.

  By performing the above steps S1 to S5 on the entire surface of the measurement object (semiconductor package 26), ultrasonic measurement and evaluation (good / bad determination) of the measurement object (semiconductor package 26) can be performed.

  In the first embodiment, the location where the amplitude intensity is maximum is the reference interface where the acoustic impedance difference is maximum. However, if the maximum amplitude intensity and the reference interface are different due to noise or the like, these are taken into consideration. Thus, it is possible to set a reference interface other than the maximum amplitude intensity.

  According to the first embodiment, not the surface of an object to be measured (for example, an electronic component, more specifically, the semiconductor package 26), but a characteristic location (an electrode joint or an area near the electrode joint) inside the semiconductor package 26. The interface between the material layers having a large acoustic impedance difference) is set as the trigger 34 by the data calculation unit 74 (or the reference interface determination unit 80 and the data calculation unit 74), and the gate 35 is set based on the trigger 34 (or The reference interface determination unit 80 and the data calculation unit 74) are set, and the inspection (measurement) of the joint is performed by the data calculation unit 74. As a result, even when the position of the interface between the solder 31 and the substrate-side pad 28 of the substrate 27 is not stabilized due to the variation caused by the thickness tolerance of the interposer 29 or the like, the measurement of the portion to be measured can be performed only in the measurement after the trigger position. Inspection (measurement) can be performed by the data calculation unit 74, and ultrasonic measurement with high accuracy is possible. Therefore, it is possible to provide a highly accurate ultrasonic measurement method and ultrasonic measurement apparatus even for a measurement object in which a plurality of interfaces intersect in the ultrasonic irradiation direction. Furthermore, an electronic component manufacturing method for manufacturing an electronic component measured by the ultrasonic measurement method and evaluated as a non-defective product, and a semiconductor package used for the ultrasonic measurement method can be provided.

  In particular, in the first embodiment, in order to solve the conventional problem of the ultrasonic measurement method, a method of taking a reference surface (reference interface) is devised to solve the conventional problem. The ultrasonic measurement method can be improved by creating a reference surface in the package or substrate manufacturing method and using the reference surface.

(Embodiment 2)
FIG. 7 is an explanatory diagram illustrating an ultrasonic measurement operation according to the second embodiment of the present invention.

  In FIG. 7, a semiconductor package 37 as another example of the measurement object includes, as an example, a substrate 38, a substrate-side pad 39 provided on the upper surface of the substrate 38, and an interposer 40 bonded to the substrate 38. The interposer side pad 41 provided on the lower surface of the interposer 40, the solder 42 as an example of a bonding material for bonding the substrate side pad 39 and the interposer side pad 41, and the interposer 40 and flip chip connection (not shown). And the like, a resin mold 44 that covers the semiconductor chip 43, and a mark 45 that is disposed inside the interposer 40 at a position in contact with the interposer-side pad 41. The semiconductor package 37 is different from the semiconductor package 26 of the first embodiment in that a mark 45 is formed.

  Such a semiconductor package 37 is manufactured as follows.

  First, an interposer 40 having a large number of interposer-side pads 41 on the lower surface and having marks 45 arranged at positions in contact with the interposer-side pads 41 inside the interposer 40 is prepared.

  Next, the semiconductor chip 43 is connected to the upper surface of the interposer 40 by flip chip connection or the like.

  Next, a resin mold 44 is formed by covering the semiconductor chip 43 on the interposer 40 with an insulating synthetic resin.

  Thereafter, the solder 42 is formed on each interposer side pad 41 of the interposer 40 or each substrate side pad 39 of the substrate 38.

  Next, each interposer side pad 41 of the interposer 40 and each board side pad 39 of the substrate 38 are connected via the solder 42.

  By manufacturing in this way, an interface that can function as a reference interface (a reference surface for determining whether or not a joint is good) is formed as a mark 45 at the time of manufacture. That is, the reference interface capable of acquiring an ultrasonic waveform signal by being reflected during ultrasonic irradiation is thin as a mark 45 at a position in contact with the interposer side pad 41 inside the interposer 40 inside the semiconductor package 37. A metal layer is formed. As the metal layer formed as the mark 45, a material having an acoustic impedance difference from the interposer 40 may be used. When glass epoxy is used for the interposer 40, the acoustic impedance is 2.9 to 3.6. Therefore, considering the acoustic impedance inherent in the substance, for example, copper (acoustic impedance is 41.8), silver (acoustic impedance is 37.8), Au (acoustic impedance is 62.5), or the like can be used as the material of the mark 45.

The material of the substrate 38 is an epoxy resin, and the material of the substrate side pad 39 and the material of the interposer side pad 41 are copper (Cu). The material of the interposer 40 is an epoxy resin. The material of the solder 42 is a solder alloy such as Sn / Pb / Cu or Sn / Pb / Ag, and a lead-free solder such as Sn / Ag / Cu or Sn / Cu. The material of the semiconductor chip 43 is Si. The material of the resin mold 44 is a mixture of an epoxy resin and a filler (SiO ₂ ). The material of the mark 45 is gold (Au).

  As the semiconductor package 37 in the second embodiment, a CSP package having the same package size and silicon size is used as an example.

  Here, it is necessary to reduce the thickness of the mark 45 as much as possible so that the influence is reduced even if the mark thickness in each electrode (pad) 41 varies. As an example of a method for forming the mark 45, the mark 45 may be formed by vacuum deposition or the like before the electrode pad 41 is formed. More specifically, the mark 45 can be formed by installing a metal mask having an opening for forming the mark 45 on the interposer 40 and depositing gold or the like on the interposer 40. The positions of the marks 45 may be on all the interposer-side pads 41 or may not be formed on some of the pads 41. For example, as shown in FIG. 7, when there is a path from the resin mold 44 to the solder 42 via the interposer 40 and a path from the resin mold 44 to the solder 42 via the Si chip 43 and the interposer 40, the electrodes are the same path. When there is little difference in the measurement results between the two, the mark 45 may be formed only on the two pads 41. However, since the thickness and the like actually vary even in the same path, it is possible to measure with higher accuracy by forming the mark 45 on each electrode and measuring. The maximum size of the mark 45 is the size of the pad 41, and the minimum size is preferably an ultrasonic spot size (50 μm (110 MHz) to 150 μm (10 MHz), depending on the frequency). From the viewpoint of forming the mark 45, the smaller the size, the more difficult the formation. With this mark 45, it is possible to easily set the trigger position and to perform ultrasonic measurement with little influence of variation.

  Next, the ultrasonic measurement method according to the second embodiment will be described.

  As in the first embodiment, ultrasonic waves are transmitted and received from the ultrasonic probe 21 using water 25 as a medium.

  Next, based on the waveform obtained by the ultrasonic probe 21, the measured part (joint part between the solder 42 and the substrate 38) is evaluated. Unlike the first embodiment, in the second embodiment, The data calculation unit 74 uses a reflected wave from the mark 45 as another example of the reference interface as a trigger. Information about the mark 45 (for example, information that the mark 45 is formed in the semiconductor package 37, information such as the size, arrangement position, and acoustic impedance value of the mark 45) is stored in the measurement position data memory 77.

  In the second embodiment, since gold (Au) is used for the mark 45, the acoustic impedance difference (acoustic impedance difference between the mark 45 and the interposer side pad 41) is 62.5. Then, the difference in acoustic impedance between the mark 45 and the interposer side pad 41 is larger than the difference between the interposer side pad 30 and the interposer 29 in the first embodiment, and the data calculation unit 74 can easily set the trigger. can do.

  As described above, in the second embodiment, the mark 45 is embedded in the semiconductor package 37 (an embedded object), and the material of the mark 45 or the material of the interposer 40 is freely set to adjust the acoustic impedance difference. And a trigger having a large acoustic impedance difference can be generated.

  FIG. 8A is an explanatory diagram showing an ultrasonic measurement operation at time t = 0 in the second embodiment, and FIG. 8B is a diagram showing a waveform in the ultrasonic measurement operation at time t = 0 in the second embodiment. It is. FIG. 9A is an explanatory diagram showing an ultrasonic measurement operation at time t = 1 in the second embodiment, and FIG. 9B shows waveforms in the ultrasonic measurement operation at time t = 1 in the second embodiment. FIG.

  As shown in FIGS. 8A and 8B, here, a description will be given of a structure in which a mark 45 is embedded in a semiconductor package 37. FIG. Here, the focal point is first focused on the interface of the mark 45, the focal position is further adjusted with reference to that point, and the target solder interface is observed.

First, consider focusing the ultrasonic wave from the ultrasonic probe 21 on the junction between the interposer 40 and the mark 45 by the ultrasonic probe driving unit 21a. Here, as described above, the generation time T _trig of the reflected wave at the interface between the interposer 40 and the mark 45 is calculated in advance by the data calculation unit 74 based on the thickness and sound speed of the components of the semiconductor package 37. Keep it. Note that T _trig is the time when the reflected waveform on the surface of the resin mold 44 is set to time t = 0. In the second embodiment, since there is a tolerance (thickness variation) between the interposer 40 and the silicon of the semiconductor chip 43 provided around the interposer 40, it is the most in a section of T _trig ± ΔT including a minute time ΔT in the vicinity thereof. Find the focal length at which the waveform increases.

As shown in FIG. 8B, since the reflected wave at the interface between the trigger, the interposer 40 and the mark 45, has a larger intensity value than the reflected wave at the other interface, the waveform itself is easy to measure. Here, in order to find a position where the trigger has the highest signal intensity, the ultrasonic probe 21 is moved to the semiconductor package side (the lower side in the drawing of FIG. 8A) by the ultrasonic probe driving unit 21a. Thereafter, the distance of the focal distance D _trig when the trigger waveform intensity becomes the largest is stored in the internal memory by the data calculation unit 74.

Subsequently, as shown in FIG. 9A, the ultrasonic probe 21 is focused on the solder 42 and the board-side pad 39 by the ultrasonic probe driving unit 21a. The descent distance ΔD from the focal distance D _trig is obtained by measuring the same type of semiconductor package (that is, the same material) in advance by the data calculation unit 74.

As shown in FIG. 9B, the descent distance ΔD is calculated based on the thickness of the solder 41 and the sound speed by the data calculation unit 74 using the data calculation unit 74 to calculate the arrival time of the ultrasonic wave from the focal length D _trig. 74 is specified.

Next, the ultrasonic probe 21 is lowered to the semiconductor package side (the lower side of the drawing in FIG. 9A) until the waveform at the joint portion between the solder 42 and the substrate 38 has the highest strength. The descent distance from the focal distance D _trig is ΔD. In actual measurement, the descent distance ΔD is obtained only in the initial measurement, and in the subsequent measurements, the ultrasonic probe driving unit 21a adjusts based on the focal distance D _trig. Thus, it can be in a focused state.

  By this method, it is possible to correct the variation in the focal position caused by the thickness tolerance (thickness variation) of the semiconductor package 37.

(Embodiment 3)
FIG. 10 is a diagram illustrating an ultrasonic measurement operation according to the third embodiment of the present invention.

  In FIG. 10, the difference between the third embodiment and the second embodiment (FIG. 7) is that in the third embodiment, instead of the mark 45 in the interposer 40 in the second embodiment, the difference between the third embodiment and the second embodiment is shown in FIG. A mark 46 is provided, and this mark 46 is another example of the reference interface. Here, since there is no layer below the substrate 38 (the lower side of the drawing in FIG. 10), the material of the mark 46 may be a material that totally reflects ultrasonic waves. For example, the mark 46 may be a void layer. it can. It is also conceivable to change the material of the substrate 38, increase the acoustic impedance difference between the material of the substrate 38 and the material of the substrate-side pad 39, and increase the reflection intensity of the ultrasonic waves. In this case, the interface between the material of the substrate 38 and the material of the substrate-side pad 39 is still another example of the reference interface.

(Embodiment 4)
In the fourth embodiment of the present invention, in any one of the first to third embodiments described above, in the ultrasonic flaw detection for searching for a flaw inside the measurement object (semiconductor package), the trigger is used for the ultrasonic flaw detection. A method used for the focus position adjustment of the touch element 21 will be described.

  Ultrasonic flaw detection often uses a focus type probe, and for that reason, it is important to align the focus with the measurement object (semiconductor package). As already described, since there is a variation (tolerance) in the thickness of the semiconductor package, even if the focal position is set in advance, an error is generated by the thickness of the semiconductor package that is actually measured. In the fourth embodiment, the focus position is adjusted for each semiconductor package by using a trigger.

  By performing ultrasonic flaw detection after performing focus position alignment in this way, it is possible to perform an inspection with improved accuracy.

  The previous embodiment of the present invention is characterized by analyzing the amplitude intensity signal of the ultrasonic reflected wave. However, there are basic methods, problems, and solutions regarding other means such as the transmission method. If it is the same case and it is a measuring object which has the same structure, the method of Embodiment 4 may be applicable.

  Needless to say, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  For example, the material of each pad can be copper, gold, silver, or the like.

  In addition, as shown in the conventional example, when there is a lead wire in the electronic component and the lead wire hinders the measurement work, the lead wire other than the region where the ultrasonic wave may be blocked or obstructed A reference interface may be set in the region.

  It is to be noted that, by appropriately combining any of the above-described various embodiments, the effects possessed by them can be produced.

  Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included therein unless they depart from the scope of the invention as defined by the appended claims.

The ultrasonic measurement method of the present invention can be applied to uses such as nondestructive inspection of a semiconductor package in which a plurality of interfaces are laminated inside and the plurality of interfaces intersect in the ultrasonic irradiation direction. The electronic component manufacturing how the present invention can be applied to the electronic component has been non-defective evaluated measured by the ultrasonic measurement method in the electronic component manufacturing how to manufacture a product.

Schematic configuration diagram of an ultrasonic measurement apparatus for carrying out the ultrasonic measurement method of Embodiment 1 of the present invention Block diagram of the control unit and the like of the ultrasonic measurement apparatus according to the first embodiment Explanatory drawing which shows the ultrasonic measurement operation | movement of Embodiment 1. FIG. The figure which shows the ultrasonic waveform in the ultrasonic measurement of Embodiment 1. (A) The figure which shows the waveform strength evaluation of the gate position in the ultrasonic measurement of Embodiment 1, (b) The figure which shows one period of the master data in the ultrasonic measurement of Embodiment 1, (c) Embodiment 1 Of correlation coefficient in ultrasonic measurement The figure which shows the correlation coefficient data sequence of the ultrasonic measurement of the said Embodiment 1 which expressed FIG.4 (c) in detail Flowchart of ultrasonic measurement operation of the first embodiment Explanatory drawing which shows the ultrasonic measurement operation | movement of Embodiment 2 of this invention. Explanatory drawing which shows the ultrasonic measurement operation | movement at the time t = 0 of Embodiment 2. FIG. The figure which shows the waveform in the ultrasonic measurement operation | movement at the time t = 0 of Embodiment 2. FIG. Explanatory drawing which shows the ultrasonic measurement operation | movement at the time t = 1 of Embodiment 2. FIG. The figure which shows the waveform in the ultrasonic measurement operation | movement at the time t = 1 of Embodiment 2. The figure which shows another system of the ultrasonic measurement operation | movement of Embodiment 2. FIG. Basic configuration of conventional ultrasonic measurement method Schematic diagram of conventional ultrasonic measurement The figure which shows the ultrasonic waveform in the conventional ultrasonic measurement The figure which shows the waveform of the ultrasonic reflected wave by the conventional ultrasonic measurement The graph which shows the case where the maximum value of a waveform strength exceeds the threshold value which is the determination criterion of the quality determination in the ultrasonic measurement operation of Embodiment 1, and a quality product is determined The graph which shows the case where the maximum value of waveform intensity is smaller than the threshold value which is the determination criterion of the quality determination in the ultrasonic measurement operation of Embodiment 1, and a defective product is determined

Explanation of symbols

21 Ultrasonic probe 25 Water 26, 37 Semiconductor package 27, 38 Substrate 28, 39 Substrate side pad 29, 40 Interposer 30, 41 Interposer side pad 31, 42 Solder 32, 43 Semiconductor chip 33, 44 Resin mold 41 Embedded object 74 Calculation unit

Claims (7)

The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
The measurement object is an electronic component, and the measurement object interface is an electrode bonding portion where electrodes are bonded to each other with a bonding material inside the electronic component or a portion adjacent to the electrode bonding portion, and the measurement target. After measuring the interface at the computing unit, ultrasonic measuring how to evaluate the bonding state of the electrode junction at the measurement target surface by the arithmetic unit. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
Wherein when detecting the waveform signal, the reference interface, ultrasonic measurement methods Ru interface der having a maximum amplitude intensity among the plurality of interfaces in the object to be measured. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
Wherein when detecting the waveform signal, the reference interface, ultrasonic measurement methods Ru surface der of the measurement target within the embedded buried object. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When the waveform signal is detected, the object to be measured is a semiconductor package, and the reference interface is an electrode bonding portion where the electrodes are bonded to each other by the bonding material inside the semiconductor package or the electrode bonding a adjacent portions in section, and located at the interface of the two layers of different materials, ultrasonic measurement methods. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When receiving the ultrasonic waveform signal, the ultrasonic wave transmitted from the ultrasonic probe receives the ultrasonic waveform signal reflected by a plurality of interfaces of the measurement object,
Furthermore, after detecting the waveform signal at the reference interface and before measuring the measurement target interface by the calculation unit, based on the waveform signal received while bringing the ultrasonic probe and the measurement target close to each other ultrasonic measuring how to adjust the position of the ultrasonic probe Te. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected from each of the multiple interfaces within the measurement object,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the measurement object is detected by the calculation unit,
When measuring the measurement target interface of the measurement target specified by using the waveform signal of the reflected wave at the reference interface as a starting point,
When the measurement target interface is measured by the calculation unit, a waveform signal detected after the waveform signal of the reflected wave at the reference interface is previously determined based on the waveform signal of the reflected wave at the reference interface. compared to input non-defective waveform signal, the measurement target row cormorants ultrasonic measuring method characterize interface by the comparison result. The ultrasonic probe receives the waveform signals of the ultrasonic waves reflected at each of the multiple interfaces in the electronic component,
Based on the amplitude of the waveform signal received by the ultrasonic probe, the waveform signal of the reflected wave at the reference interface inside the electronic component is detected by the arithmetic unit,
Perform measurement by measuring the measurement target interface of the electronic component identified by using the waveform signal of the reflected wave at the reference interface as a starting point ,
An electronic component manufacturing method using the electronic component evaluated as a good product as a product.

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