JP2847843B2 - Thermal expansion measuring device for semiconductor integrated circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal expansion measuring device for measuring thermal expansion, warpage, and other thermal deformation caused by heat generation during energizing operation of a semiconductor integrated circuit or the like.

[Prior art] Conventionally, there is no good method for quickly and easily measuring how much thermal expansion is occurring and how much thermal deformation is occurring when a semiconductor integrated circuit (LSI) is energized. Or measure the heating value with a radiation thermometer, assuming the temperature gradient inside the semiconductor integrated circuit,
In addition, there has been only an indirect method such as calculating the displacement at each part by calculating the boundary condition from the shape of the semiconductor integrated circuit.

[Problems to be Solved by the Invention] However, it is difficult to measure the thermal expansion of the semiconductor integrated circuit with a conventional displacement meter or the like because it is difficult to specify a small area on the semiconductor integrated circuit. It was possible.

In addition, a method of estimating the heat generation by measuring the temperature distribution existing in the semiconductor integrated circuit with a radiation thermometer, creating a heat conduction equation, calculating the heat flow therefrom, and estimating the thermal deformation due to thermal expansion, Since the displacement was not directly measured, it could not be said that the correct value of the thermal expansion was given.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a displacement amount such as warpage or distortion caused by thermal expansion or thermal contraction during energization generated on a semiconductor integrated circuit or a semiconductor integrated circuit. It is an object of the present invention to provide a device for quickly and precisely measuring the state of a deformation or the like.

Means for Solving the Problems In order to achieve this object, a thermal expansion measuring device for a semiconductor integrated circuit according to the present invention includes an electric contact unit for flowing a signal current to each conducting line of the semiconductor integrated circuit; Drive control means for electrically operating the semiconductor integrated circuit and controlling the signal current through the electrical connection means, and heterodyne measurement for measuring the amount of displacement caused by thermal expansion on the semiconductor integrated circuit caused by the current for each small area Means.

[Operation] According to the present invention, the electric contact means contacts each energizing line of the semiconductor integrated circuit. The drive control means electrically operates the semiconductor integrated circuit, and controls the signal current through the electrical connection means. For this reason, the temperature of the semiconductor integrated circuit rises, and the position change of any small area on the surface thereof is measured with high accuracy by the heterodyne measuring means.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic functional block diagram. Hereinafter, FIG. 1 will be described.

A semiconductor integrated circuit for measurement is mounted on a fixed base such as a socket having an electrical contact function, and these are electrically controlled by a power supply for a semiconductor sample controlled from a computer and various signal control circuits. Has become. Further, the fixed portion of the semiconductor integrated circuit can be freely moved by moving means such as a table for controlling the position movement of the X, Y and Z axes.

The position of these position moving means is controlled by a computer. In a semiconductor integrated circuit, surface information such as displacement or unevenness on the surface is measured using an optical system as shown in FIG. 2 by using laser light. In the measurement, the optical signal is converted into an electric signal and input to a computer through a signal processing circuit. The computer processes the measured data using an attached ROM and RAM, and finally outputs the data to a data display unit such as a CRT. It has become. The above is the outline of the block diagram in FIG.

 Next, the optical system will be described mainly with reference to FIG.

2, the linearly polarized laser light output from the laser light source (10) reaches the polarization beam splitter (14) via the isolator (12) and has a vibration plane parallel to the paper surface of FIG. It is split into P-polarized light and S-polarized light having a vibration plane perpendicular to the plane of FIG. At this time, the vibrating surface of the laser light is inclined by 45 ° with respect to the plane of FIG.

The P-polarized light has the same frequency f ₀ as the laser light,
The light is reflected by the mirror 16 and passed through the polarizing beam splitter (18). After being reflected by the mirror (20), the S-polarized light passes through the acousto-optic modulators (22) and (24) and undergoes a shift of frequencies + f ₁ and −f ₂ , so that the frequencies f ₀ + f _1. −f _2, and thereafter enter the polarization beam splitter (18). In the polarization beam splitter (18), the S-polarized light beam having undergone the frequency shift and the P-polarized light beam are superimposed and then split into two in the non-polarized beam splitter (26).

The light reflected by the non-polarizing beam splitter (26) is converted into a polarizer (28) with a polarization axis inclined by 45 °.
, The light that has caused the P-polarized light and the S-polarized light to interfere with each other, that is, the reference beat frequency f _B = (= | f ₁ −f ₂ |)
Is detected by the reference beat light sensor (30). Therefore, the reference beat signal Sf of the frequency f _B
B is output from the reference beat light sensor (30). The light transmitted through the non-polarizing beam splitter (26) is further divided into two by the non-polarizing beam splitter (32). Hereinafter, the light beam transmitted through the non-polarization beam splitter (32) is referred to as a first light beam, and the light beam reflected by the non-polarization beam splitter (32) is referred to as a second light beam.

The first light flux includes a surface (reflection surface) of the semiconductor integrated circuit (34), a mirror (38) provided integrally with the objective lens (36), and polarized light placed above the objective lens (36). The light is made incident on a first heterodyne interference system constituted by a beam splitter (40) and the like.

In addition, the second light flux includes a mirror (42) provided integrally with the objective lens (36), a mirror (44) having a fixed position,
Second composed of a polarizing beam splitter (46)
To the heterodyne interference optical system.

In the first heterodyne interference optical system, the frequency
first beam is a composite wave of the P-polarized light and the frequency f ₀ + f ₁ -f ₂ of the S-polarized light of the f ₀ is first divided by the polarization beam splitter (40). The P-polarized light transmitted through the polarization beam splitter (40) is converted into circularly polarized light by being transmitted through the λ / 4 plate (50), and then is condensed on the surface of the semiconductor integrated circuit through the objective lens (36). . This semiconductor integrated circuit 34)
The reflected light from the surface of
By passing through the / 4 plate (50), the vibration plane is converted into the polarized light rotated by 90 ° with respect to the original P-polarized light, that is, converted into the S-polarized light, and is reflected by the polarizing beam splitter (40). Reach the polarizer (52). The light reflected from the surface of the semiconductor integrated circuit (34) is subjected to phase shift and scattering due to unevenness of the Al fine wire and the protective film on the surface.

A polarization beam splitter (40) of the first high speed
The S-polarized light reflected by the mirror is reflected by a mirror (48) whose position is fixed, is converted into circularly polarized light by passing through a λ / 4 plate (50), and then is converted into a mirror (38) through a condenser lens (54). ) Is collected on the surface. The reflected light from the mirror (38) passes through the λ / 4 plate (50) again through the condenser lens (54), so that the vibration plane is rotated by 90 ° with respect to the original S-polarized light. Since the light is converted to polarized light, that is, P-polarized light, it passes through the polarizing beam splitter (40) and reaches the polarizer (52). Since the polarization axis of the polarizer (52) is inclined by 45 ° with respect to the vibration plane of the S-polarized light and the P-polarized light, heterodyne interference due to the P-polarized light and the S-polarized light is generated in the light transmitted through the polarizer (52). And this interference light is
It is detected by the measurement beat light sensor (56). This first
Measurement beat light sensor (56) consists of a plurality, the frequency from the respective position a f _W, the signal phase difference between the signals slightly occurs _{Sf WA, Sf WB, Sf WC} , Sf _WD , Sf
_WE is output. These signals are used to measure the wavefront of the light reflected from the surface of the semiconductor integrated circuit.

In the second heterodyne interference optics, the frequency f ₀
The second light flux, which is a composite wave of the P-polarized light and the S-polarized light of the frequency f ₀ + f ₁ −f ₂ , is reflected by the mirror (33), and is first split by the polarizing beam splitter (46). The P-polarized light transmitted through the polarizing beam splitter (46) is a λ / 4 plate (5
After being converted into circularly polarized light by passing through 6), the light is condensed on the surface of the mirror (42) through the condenser lens (60). The reflected light from the mirror (42) is again passed through the λ / 4 plate (58) through the condenser lens (60), whereby the polarized light rotated 90 ° on the vibration plane with respect to the original P polarized light. That is, since the light is converted into S-polarized light, it is reflected by the polarizing beam splitter (46) and reaches the polarizer (62).

On the other hand, the S-polarized light reflected by the polarization beam splitter (46) is converted into circularly polarized light by passing through a λ / 4 plate (64), and then is passed through a condenser lens (66) to a fixed mirror (44). ) Is collected on the surface. This mirror (4
The reflected light from 4) is again polarized by the condensing lens (66) with the vibration plane rotated by 90 ° with respect to the original S-polarized light,
That is, since the light is converted into P-polarized light, it is transmitted through the polarizing beam splitter (46) and reaches the polarizer (62). The polarization axis of the polarizer (62) is higher than the vibration plane of the S-polarized light and the P-polarized light.
Since the light is transmitted through the polarizer (62), heterodyne interference due to P-polarized light and S-polarized light is generated, and the interference light is detected by the second measurement beat light sensor (68). There second measurement beat signal Sf _D of f _D is output.

The objective lens (36) includes a lens actuator (7
0) allows positioning in the optical axis direction. That is, through holes (73), (74), and (75) through which light beams pass are formed in the machine frame (72) whose position is fixed. A cylindrical lens actuator (70) is suspended concentrically with the central through hole (74), and a lens holding cylinder (78) holding the objective lens (36) is fixed to the lower end of the lens actuator (70). Have been. In this embodiment, the lens actuator (70) is an objective lens (3
6) and a semiconductor integrated circuit sample (34), which constitutes a driving device that changes the distance between them. For example, the driving device is made of an axially contractible piezoelectric ceramic, and is related to the amount of contraction corresponding to the applied voltage. Then, the objective lens (36) is positioned. The mirror (38)
And (42) are fixed to the lens holding cylinder (78) and can be moved in the axial direction integrally with the objective lens (36).

The measurement semiconductor integrated circuit (34) includes an objective lens (3
It is designed to be driven in the optical axis direction 6) and in a direction perpendicular to the optical axis. That is, on a base (88) such as an anti-vibration table, the guide device shown in FIG.
The horizontal moving table (84) guided to
Positioning is performed in the horizontal direction by a horizontal driving device (85) that can be micro-driven by a pulse motor or a piezo actuator or the like. The electrical contact member (80) guided in the vertical direction is positioned vertically by the vertical drive table (82). The vertical driving device (83) includes, for example, a pulse motor or the like, and moves the electrical contact member (80) at a distance larger than the moving distance of the objective lens (36) by the lens actuator (70). It can be driven. Further, the horizontal drive table (84) and the vertical drive table (82) described above are used to move in the horizontal direction (X direction) in the direction perpendicular to the X direction (Y direction). The horizontal Y-direction moving table (86) is mounted on a moving table (86), and is driven by a finely drivable horizontal (Y-direction) driving device (87) composed of, for example, a pulse motor or a piezo actuator. , In the horizontal direction (Y direction). Although not shown, the horizontal direction (X direction) driving device (85) and the horizontal direction (Y direction) driving device (87) each have a position detector for detecting the movement amount in the X direction and the Y direction. Each is provided. This position detecting device is constituted by a rotary encoder or a generally known optical position detector or length measuring device.

The optical interference type semiconductor thermal expansion measuring device optically constructed as described above is provided with, for example, a measurement control circuit shown in FIG. The optical sensor (56) is composed of five light receiving elements 56A, 56B, 56C, 56D and 56E as shown in FIG. 5, and the first measurement beat signals Sf _WA and Sf output from the respective sensors. _{WB, Sf WC, Sf WD,} Sf you include an amplifier 90A shown in FIG. 4, 90B, 90C, 90D, after being signal amplified in 90E, are respectively supplied to the waveform monitoring circuit (92).

The waveform monitor circuit (92) determines whether the light flux reaching the first measurement beat light sensor (56) is a plane wave, a divergent spherical wave, or a focused spherical wave, outputs a signal indicating the determination result to be described later of the data bus line (102), and outputs a signal of the first measurement beat frequency f _W to the phase difference detection circuit (106).

Hereinafter, the waveform monitor circuit will be described in detail.

The waveform monitor circuit 92 is configured, for example, as shown in FIG. That is, one digital phase difference detection circuit 94
The phase difference Δθ _CB between the beat signals Sf _WB and Sf _WC from the light receiving elements 56B and 56C arranged in the vertical direction (for example, the phase angle of the peak position of the beat signal Sf _WC is θ _C , and the beat signal Sf
When the phase angle of the peak position of the _WB and θ _B, Δθ _CB = θ _C
−θ _B ) and outputs it to the subtractor 98, while the other digital phase difference detection circuit 96 detects the phase difference between the beat signals Sf _WD and Sf _WC from the light receiving elements 56D and 56C arranged in the vertical direction. Δθ _DC (for example, assuming that the phase angle of the peak position of the beat signal Sf _WC is θ _C and the phase angle of the peak position of the beat signal Sf _WD is θ _D , Δθ _DC = θ _D −θ _C ), and the subtracter
Output to 98. The subtracter 98 calculates the phase difference Δθ _CB
Is subtracted from the phase difference Δθ _DC to obtain a subtraction value (Δθ _CB −Δθ _DC ).
Is output.

If the light beam reaching the first measurement beat light sensor 56 is a plane wave, the three light receiving elements 56B and 56B are used as shown in FIG.
The output signals of C and 56D have the same phase. Also, even if the first measurement beat light sensor 56 is inclined, as shown in FIG. 8, the output signal Sf _WB of the light receiving element 56B located above the light receiving element 56C and the output signal Sf _WB located below the light receiving element 56C. Light receiving element 56D
The phase of the output signal Sf _WD with respect to the output signal Sf _WC of the light receiving element 56C located at the center is shifted in the forward and backward directions by the same amount, that is, Δθ _CB and Δθ _DC are shifted in the positive direction. For example, in FIG. 8, the output signal Sf _{WB with} respect to the output signal Sf _WC
The phase shift [Delta] [theta] _CB and (= θ _C -θ _B, a positive value), the phase shift [Delta] [theta] _DC of the output signal Sf _WD with respect to the output signal Sf _WC (=
θ _D −θ _C , a positive value) are equal to each other (Δθ _CB
= Δθ _DC ). However, if the light beam reaching the first measurement beat light sensor 56 is a focused spherical wave, for example, as shown in FIG. 9, the output signals Sf _WB and Sf _WD of the light receiving elements 56B and 56D.
Phase, the phase shift [Delta] [theta] _DC of the output signal Sf _WD with respect to the output signal Sf _WC of the light-receiving element 56C (= θ _D -θ _C) is a negative value of. Conversely, if the light beam reaching the first measurement beat light sensor 56 is a divergent spherical wave, the phases of the output signals Sf _WB and Sf _WD are both delayed with respect to the output signal Sf _WC .
Phase shift Δθ _CB of output signal Sf _WB with respect to Sf _WC (= θ _C
−θ _B ) is a negative value. Therefore, the output signal Sf _WC for the output signal Sf _WB of phase shift [Delta] [theta] _CB and the output signal Sf _WC
Subtracted from the phase shift Δθ _DC of the output signal Sf _WD (Δ
θ _CB −Δθ _DC ) becomes closer to zero as the plane wave becomes.

The comparison / judgment circuit 100 shown in FIG. 6 includes a judgment reference range (an upper limit value (positive value) and a lower limit value (negative value) indicating a reference range including zero) preset by the setter 140 and the subtractor 98. The output signal is compared with the output signal, and when the output value (Δθ _CB −Δθ _DC ) of the subtracter 98 is within the determination reference range, it is determined that the plane wave is present,
When the output value of the subtractor 98 is larger than the upper limit of the determination reference range, it is determined that the wave is a convergent spherical wave, and when the output value is smaller than the lower limit of the determination reference range, it is determined that the wave is a divergent spherical wave. judge. Then, the comparison determination circuit 100 sends to the data bus line 102 a signal representing a determination result as to which of the plane wave, the convergent spherical wave, and the divergent spherical wave, or in addition thereto, the degree of curvature of the spherical wave. Output. The upper limit value and the lower limit value indicating the determination reference range preset in the setting unit 140 are, for example, values when the surface of the semiconductor integrated circuit 34 is shifted by a half wavelength from the beam waist position BW, or The value is smaller by a predetermined amount.

Here, the wavefront state of the light beam that has propagated to the first measurement beat light sensor 56 indicates the relative positional relationship between the focal position of the objective lens 36 and the surface of the member 34 to be measured. That is, as shown in FIG. 8, the surface of the semiconductor integrated circuit 34 is
In the case where the light beam condensed by the light beam is located at the most depressed portion, in other words, at the beam waist position BW of the light beam, the light beam reflected from the surface becomes a plane wave. However, when the surface of the semiconductor integrated circuit 34 deviates from the beam waist position BW of the light beam toward the side away from the objective lens 36, the light beam propagated to the first measurement beam and the optical sensor 56 becomes a convergent spherical wave. Conversely, when the surface of the semiconductor integrated circuit 34 deviates from the beam waist position BW of the light beam toward the side approaching the objective lens 36, the light beam transmitted to the first measurement beat light sensor 56 becomes a divergent spherical wave.

Therefore, by detecting such changes in the wavefront state using the phase difference detection circuits (94) and (96), the measurement conditions are set so that the relative distance between the semiconductor integrated circuit (34) and the objective lens (36) is always constant. Control. Then, the semiconductor integrated circuit is energized to generate thermal expansion, and its minute displacement is measured in real time by the second heterodyne interference optical system.

That is, in the first heterodyne optical system, the initial phase difference Di is set so that the light beam reflected by the semiconductor integrated circuit (34) and reaching the first measurement beat light sensor (56) as a plurality of detectors becomes a plane wave. And the initial phase difference Di
The distance from the objective lens (36) is controlled by the lens actuator (70) so that the distance between the objective lens (36) and the beam waist position BW of the light beam focused by the objective lens (36) is maintained. Control is performed so that the surfaces always match. In this manner, the positioning of the objective lens (36) is set high so that the beam waist position BW of the objective lens (36) always coincides with the surface of the semiconductor integrated circuit (34). After the precision, the displacement Z of the lens holding cylinder (78) is detected by the second heterodyne optical system. This signal Sf _d detected by measuring the beat light sensor (68), it is because it observed as a phase-shifted signal to a reference beat signal Sf _B.
The phase difference between the two signals is caused by displacement due to thermal expansion caused by energization in a specific area of the semiconductor integrated circuit being measured. At this time, the following relationship exists between the actual displacement and the observed phase difference.

That is, the difference between the phase difference Φ (t ₁ ) and the phase difference Φ (t ₀ ) observed between the reference beat signal Sf _B and the measured beat signal Sf _d at time t = t ₁ and t = t ₀ , respectively. , the amount of displaced from t = t ₀ to t = t _1.

Therefore, if the semiconductor integrated circuit continues to thermally expand due to heat generation due to energization, the measured beat light signal Sf _d
Since the phase existing between the reference beat light signal and the reference beat light signal changes, the phase is measured using the signal processing circuit shown in FIG. Reference beat light signal Sf _B, after being shaped into a pulse waveform by the waveform shaping circuit 104, is supplied to the phase difference detection circuit 106, it is supplied to the AND circuit 110 via an inverter (108). The phase difference detection circuit 106
The phase difference D between the output signal Sf _B signal Sf _WC and a reference beat light sensor frequency f _W output from the light receiving element 56c (30)
And a signal representing the phase difference D is transmitted to the data bus line.
Output to 102. The objective lens (36) and the surface of the semiconductor integrated circuit (34) are adjusted by adjusting the luminous flux reaching the first measurement beat optical sensor (56) into a plane wave by expansion on the surface of the semiconductor integrated circuit. When the optical position is initially set to the optimal optical position, the phase difference detection circuit (10
The phase difference D detected by 6) is referred to as an initial phase difference Di.

The output signal Sf _d of the second measurement beat light sensor (68), after being shaped into a pulse waveform by the waveform shaping circuit (112),
It is supplied to the AND circuit (110). AND circuit (11
0), the pulse waveform of the output signal Sf _B of the reference beat light sensor (30) is, for example, "0" and a pulse waveform of the output signal Sf _d of the second measurement beat light sensor (68) for example, "1" At one time, a clock signal of a constant frequency output from the high-frequency signal generator (114) is passed to the counter (116) and counted there. This counter (116)
Counts the clock signal in response to the phase difference between the reference beat light sensor (30) of the output signal Sf _B and second measurement beat light output signal of the sensor (68) (Sf _d), corresponding to a phase difference 2π value , A frequency dividing counter that outputs an expiration signal and starts counting again from zero. This counter (16
6) temporarily stores a count value representing a phase difference φ of 2π or less in the latch circuit (118) every predetermined time, and
Outputs a signal representing the phase difference to the data bus line (102) as necessary. The counter (120) counts an expiration signal output when the count value of the counter (116) reaches a value corresponding to the phase difference of 2π, and counts a count value N representing a phase difference of 2π units for a predetermined time. Each time, the latch circuit (122) temporarily stores a signal representing the count value N on the data bus line (102).
Output to Therefore, the output signals of the reference beat light sensor (30) are obtained by the output signals of the latches (118) and (122).
The actual phase difference Φ (= 2πN + φ) between Sf _B and the output signal Sf _{D of} the second measurement beat light sensor (68) is detected.

The change in phase obtained by the second heterodyne optical system is obtained by accurately measuring a displacement caused by heat generated by energization at a specific location on the semiconductor integrated circuit.

A method for measuring the amount of thermal expansion or thermal deformation occurring in a semiconductor integrated circuit using the above-described heterodyne interference optical system as an optical probe for measuring thermal displacement will be described.

Explaining based on the flowchart shown in FIG.
First, the X-axis direction moving table (84) and the Y-axis direction moving table (86) are moved, the position to be measured on the semiconductor integrated circuit is determined, and the vertical direction moving stage (82) is moved. Coarse adjustment is performed so that the circuit surface (34) is located at the focal position (BW) of the objective lens (36). Next, the piezo drive actuator (70) is driven by the waveform monitor circuit so that the reflected light from the semiconductor integrated circuit becomes a plane wave. If the light reflected from the surface of the semiconductor integrated circuit becomes a plane wave, it means that the semiconductor integrated circuit has been installed at the focal plane position of the objective lens. At this time, the initial phase value is determined by the second heterodyne optical system.

Next, the drive control device for the semiconductor integrated circuit is operated. The drive control device for a semiconductor integrated circuit supplies a power supply voltage to the semiconductor integrated circuit for measurement, transmits a necessary signal to the semiconductor integrated circuit, and reads a specific signal. This is a control device that can be executed by a predetermined program from the Internet. When the device is operated, the sample semiconductor integrated circuit undergoes thermal expansion due to heat generated inside, and the position where the measurement light is reflected changes. Therefore, the reflected light from the reflecting surface of the semiconductor integrated circuit is always received, and the piezo drive support cylinder is moved so that the first heterodyne interference system always has a constant plane wave. By applying feedback so as to always maintain such a state, the movement of the piezo drive support cylinder can be measured by the second heterodyne interference optical system, and the amount of thermal expansion finally generated on the semiconductor integrated circuit can be measured. The measurement is performed by measuring the phase difference detected by the second heterodyne optical system at regular intervals with a high-frequency clock and displaying it on a display device such as a CRT, so that the time change of the displacement due to thermal expansion occurring on the semiconductor integrated circuit is obtained. Can be measured.

Using this first measuring method, the displacement due to thermal expansion at a specific portion on the semiconductor integrated circuit can be instantaneously measured, so that the Al thin wire may be broken in a certain region on the semiconductor integrated circuit. , A measurement result that the amount of thermal displacement observed at the position is very small or not observed at all is obtained. Therefore, the first method can be used for failure analysis of a semiconductor integrated circuit.

The second embodiment is a method in which the first embodiment is applied to measure and display thermal deformation due to thermal expansion occurring on the front surface of a semiconductor integrated circuit.

In this method, if necessary, the uneven shape on the front surface of the semiconductor integrated circuit is measured before energization and stored in the RAM. Hereinafter, the semiconductor integrated circuit sample is positioned at the measurement start position, and the first
The thermal displacement is measured by the thermal expansion measurement method of
After that, the X-axis table and the Y-axis table are moved to a pre-programmed measurement position, and the next measurement is started. By repeating such a method, it is possible to measure the time change due to thermal expansion in the entire semiconductor integrated circuit, and after all the measurements are completed, the data stored in the RAM at an arbitrary time is stored on the CRT in three-dimensional information. By including and displaying, it is possible to measure the amount of deformation such as warpage or distortion caused by thermal expansion generated in the entire semiconductor integrated circuit. By using the second method, the thermal deformation occurring in the entire semiconductor integrated circuit can be measured, so that information such as how much stress is generated in the package to which the semiconductor integrated circuit is bonded can be obtained. In other words, it can be said that this is a measurement method capable of examining in detail the influence of heat deformation of a semiconductor integrated circuit which will be enlarged and highly integrated in the future.

Next, a modification of the second embodiment will be described. First, before energizing the semiconductor integrated circuit, the surface shape of the entire surface of the semiconductor integrated circuit or a specific area to be measured is measured, and RAM is measured.
To memorize it. Thereafter, the drive control device for the semiconductor integrated circuit supplies current to the semiconductor integrated circuit, outputs a necessary signal, and waits for a predetermined time. This is because it is necessary to wait until the semiconductor integrated circuit thermally reaches an equilibrium state and becomes stable after energization. After a certain period of time, the surface shape of the previously measured area is measured, and the measured data is stored in the RAM and output three-dimensionally to a display device such as a CRT. By superimposing the three-dimensional image after energization on the three-dimensional image of the semiconductor integrated circuit before energization and changing the color and outputting the same, if deformation due to heat expansion caused by heat generation during energization of the semiconductor integrated circuit occurs, The state of the deformation can be read from the three-dimensional image. Since the thermal expansion generated on the semiconductor integrated circuit can be measured in detail by such a method, it is possible to estimate the distribution of the stress generated in each portion from the amount of deformation generated on the semiconductor integrated circuit.

Further, as another application example of the present embodiment, an electric signal is sent to a specific portion of a semiconductor integrated circuit, and a difference in a time change of a thermal displacement amount due to a thermal expansion of the portion causes a difference in a time at a bonding surface existing in a fine line pattern. It can also be used to find places such as defect defects, to find places where disconnection has occurred, and to estimate the length of electrical life of junctions at measurement locations.

[Effects of the Invention] As described in detail above, the present invention can measure the amount of thermal expansion and the amount of thermal deformation of a semiconductor integrated circuit with high accuracy for each arbitrary small area. The effect is that it can be measured quickly and precisely and is very practical.

[Brief description of the drawings]

1 to 6 show an embodiment of the present invention. FIG. 1 is a block diagram, FIG. 2 is a configuration diagram of a heterodyne interference optical system, and FIG.
FIG. 4 is a block diagram showing a measurement control circuit, FIG. 5 is a schematic diagram of a multi-segment optical sensor, FIG. 6 is a block diagram of a phase difference detection circuit, FIG. 7
FIG. 9 to FIG. 9 are diagrams for explaining output signals from the multi-segment optical sensor, FIG. 10 is a flowchart of the first embodiment, and FIG. 11 is a flowchart of the second embodiment.

Claims (1)

(57) [Claims] An electric contact means for flowing a signal current to each conducting line of a semiconductor integrated circuit, and a drive control means for electrically operating the semiconductor integrated circuit and controlling the signal current through the electric connection means And a heterodyne measuring means for measuring an amount of displacement due to thermal expansion on the semiconductor integrated circuit caused by the current for each small area, and a thermal expansion measuring device for the semiconductor integrated circuit.