JPH06308038A - Semiconductor element inspection device - Google Patents

Abstract

PURPOSE:To provide a semiconductor element inspection device capable of stably discriminating shape defect and the like of transparent resin of semiconductor element regardless of the kind and size of the resin. CONSTITUTION:A test system comprises a holder 2 to linearly arrange the transparent resin part 1c of a semiconductor element 1 having an LED element part 1a, lead part 1b and a transparent resin part 1c, a moving line 3 to move the transparent resin part 1c together with a holder 2, a luminous part 4 to irradiate a beam 4a on the transparent resin part 1c, a receiver 5 to receive the beam 4b as a diffusion reflection light, and an oblique reflection mirror 6 to adjust focus of the reflection light to the receiver 5. With the receiver 5, the beam 4b coming after diffusion reflection from the defect surface such as concave and covex of the transparent resin part 1 is received and based on the output level of the electric signal converted from the beam, the surface shape defect of the transparent resin part 1c, the properness of inside void are discriminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor element inspection apparatus used for defect shape and void inspection of a semiconductor sealing transparent resin using a semiconductor light emitting element.

[0002]

2. Description of the Related Art In recent years, all the visual inspections and void inspections such as the defect shape of the transparent resin portion of a semiconductor element have been inspected at the final stage of the manufacturing process.

If the shape of the transparent resin portion is defective, for example, the surface of the transparent resin portion is partially chipped, cracked, or voids are formed inside the transparent resin, the semiconductor element sealed by the transparent resin is The characteristics deteriorate. Also, it was treated as a defect in appearance. Therefore, conventionally, after assembling the sealing resin, the quality of the defect shape of each semiconductor sealing resin is inspected by using a semiconductor element inspection device.

A conventional semiconductor device inspection apparatus will be described below with reference to the drawings. 13 to 18 are a side view showing a configuration of a conventional semiconductor device inspection apparatus and a diagram showing image results.

The conventional semiconductor device inspection apparatus shown in FIG. 13 has a light emitting diode portion 81a and a lead portion 8 to be inspected.
1b and a fixed work base 82 for fixing the transparent resin portion 81c of the semiconductor element 81 having the transparent resin portion 81c,
It is composed of a translucent light diffusing plate 83 and a sequential scanning type television camera 84, and has a mechanism for continuously moving in the horizontal direction. In addition, the progressive scanning television camera 8
4 has a built-in video signal imaging circuit having a binarization circuit. Then, when the parallel illumination light 85 is incident on the light diffusion plate 83, the illumination light 85 is diffused to become diffused light 86, which is incident on the transparent resin portion 81c which is the inspection object.

The operation of the conventional semiconductor encapsulating resin inspection configured as described above will be described below.

First, FIG. 13 is a schematic side view showing the inspection of the shape of a normal semiconductor sealing resin. As shown in FIG. 13, the semiconductor element 81 is fixed by the fixed work table 82, and the illumination light 85 is irradiated. Then, the illumination light 85 that is incident on the light diffusion plate 83 in parallel is diffused and is incident on the transparent resin portion 81c as a diffused light 86 with a uniform light amount. The diffused light 86 passes through the transparent resin portion 81c and sequentially enters the scanning television camera 84. Sequential scanning type television camera 8
Reference numeral 4 denotes a video signal imaging circuit that performs a pixel separation process by binarizing a signal corresponding to incident light and outputs it as an image to a monitor device or the like.

If the transparent resin portion 81c is normal,
Since there are no irregularities such as cracks or chips and shape defects such as internal voids on the surface, an image with uniform brightness can be obtained as shown in FIG.

On the other hand, as shown in FIG. 15, the illumination light 85 incident in parallel to the light diffusing plate 83 is diffused by the light diffusing plate 83, and is diffused into the transparent resin portion 81c with a uniform light amount.
When the light is incident as 6 and is reflected by the light emitting diode portion 81a and the lead portion 81b inside the transparent resin portion 81c, the image of the progressive scanning television camera 84 is, as shown in FIG. 16, the light emitting diode portion 81a and the lead portion 81b. The part corresponding to and becomes a black part.

Further, as shown in FIG. 17, the transparent resin portion 8
In the case where the 1c is defective such as uneven cracks or chips and shape defects such as internal voids, the diffused light 86 is transmitted through the transparent resin portion 81.
The image of the progressive scanning type television camera 84 is as shown in the figure because the portion corresponding to the defective portion is further diffused and diffracted at the defective portion such as uneven cracks or chips on the surface of c and the void inside and the portion corresponding to the defective portion becomes dark. As shown in FIG. 18, the image becomes a dark image of the defective portion.

Conventionally, these image data are processed by a microcomputer or the like to discriminate between a normal transparent resin and a defective transparent resin having uneven cracks, chips, internal voids and the like. .

[0012]

However, in the above-mentioned conventional structure, the progressive scanning television camera 8 has a capability of detecting irregular cracks, chips, voids, etc. on the transparent resin surface.
It is limited to the scanning line resolution of 4 and cannot detect minute objects.

The pixel resolution δ is expressed by the following equation (1). δ = 3L / N (1) However, L: Work size N: Number of scans in the vertical direction For example, the minimum resolution for judging defects in the sealing resin within a work size of 50 mm is usually Assuming that the number of effective scanning in the vertical direction of the progressive scanning type television camera of N is about 250, δ = 0.6 mm according to the equation (1), and a light / dark pattern of less than that, that is, a defect due to cracks, chips or voids of 0.6 mm or less. Can't recognize. If the transparent sealing resin part has cracks, chips, voids, etc., when diffused light is applied to the defective surface, the diffused light does not pass through the transparent sealing resin part, and diffuse reflection and diffraction occur on the defective surface. Due to the phenomenon, the image displayed on the progressive scanning television camera becomes dark. The other normal parts have an image of uniform brightness. Therefore, the resolution is limited by the number of scanning lines of the progressive scanning television camera.

Further, if it is attempted to simultaneously recognize defects in a plurality of transparent sealing resin portions, the work size becomes large, the resolution is lowered, the recognition range of the defective surface is lowered, and the time required for inspection becomes long. That is, in order to shorten the inspection time, it is necessary to detect defects in a plurality of transparent resin portions, which increases the work size and lowers the resolution. Further, the inspection time is greatly affected by the total number of data, that is, the number of pixels. Therefore, if the number of horizontal and vertical scanning lines is increased, the inspection time will be significantly lengthened. In order to significantly reduce these inspection times, a data compression circuit and a high-speed microcomputer must be used to process the video signal, which is considerably expensive. Further, since many data processing circuits, a binarization circuit, a pulse generation circuit, a synchronization signal generation circuit, a shift register, etc. are required, the device becomes complicated and large in size.

Further, since the video signal level increases or decreases due to the change of the illumination condition, and therefore the threshold level also increases or decreases, the binarization of the video signal may vary, resulting in an erroneous determination. . The same thing happens with ambient light.

Further, as described above, the transparent resin portion 81
When a part of the diffused light 86 radiated to c is shielded by the light emitting diode portion 81a and the lead portion 81b inside, they become a black portion on the image by the progressive scanning television camera 84 as shown in FIG. . Therefore, when the transparent resin portion 81c facing the light emitting diode portion 81a and the lead portion 81b has an uneven defect, it cannot be recognized as a defect and an undetectable portion occurs.

As described above, in the conventional semiconductor device inspection apparatus, there is a large problem that there is an undetectable shape defect and an erroneous judgment is made, and the image processing circuit is complicated and the apparatus itself is large and expensive. There was a problem.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a semiconductor element inspection apparatus for inspecting a shape defect or the like of a semiconductor sealing resin in a non-contact manner.

[0019]

In order to solve the above-mentioned problems, the semiconductor device inspection apparatus of the present invention has the following structure. That is, a holder part for linearly arranging the transparent resin part of a semiconductor element to be inspected having a light emitting diode part, a lead part and a transparent resin part, a movement line for moving the transparent resin part together with the holder part, and a transparent resin part A light emitting unit that irradiates the first beam onto the light receiving unit, a light receiving unit that receives the second beam that is the diffuse reflected light of the first beam emitted from the light emitting unit, and an elliptical reflecting mirror that focuses the reflected light on the light receiving unit. I have it. Further, in such a device, the light emitting section includes a light emitting element, a pulse driving section having a circuit for pulse driving the light emitting element, and a collimator for collimating an elliptical light beam emitted from the light emitting element to obtain a parallel beam. An optical system, a P-polarizing plate that transmits a P-polarized beam from a parallel beam and emits a P-polarized beam, a beam expander optical system that includes a lens group, and a P-polarized parallel elliptical beam by changing the beam width of the P-polarized beam. And a linear beam slit for exchanging the P-polarized parallel elliptical beam into an arbitrary shape. Furthermore, the light receiving section has an elliptical reflecting mirror having an elliptical shape on the upper side,
A hemispherical wide-angle lens installed near the focal point for receiving the second beam, an interference filter, and a second reflected light.
A light receiving element that receives a beam and performs photoelectric conversion, a drive unit that has a circuit that operates the light receiving element, an output level of the electric signal output from the light receiving element, and a reference level that cuts an electric signal below a predetermined reference output level. A threshold circuit section and a discrimination circuit section that outputs a discrimination signal based on the electric signal output from the reference level threshold circuit are provided.

[0020]

According to the above construction, the light emitting portion irradiates the surface of the transparent resin portion of the semiconductor element only with the vertical direction line beam light of the P-polarized component at an angle at which the incident angle becomes the polarization angle, and the elliptical reflecting mirror. By the light receiving part provided at the focal point, the reflected light of the beam diffused and reflected from the surface of the semiconductor encapsulating resin defect part is once condensed by the elliptical reflecting mirror, and by the hemispherical wide-angle lens and the interference filter of the light receiving part, By selecting the wavelength of the diffuse reflected light and condensing only an arbitrary light beam on the light receiving element, and by determining the presence or absence of a defect state of the transparent resin portion based on the output level of the electric signal obtained by photoelectrically converting it, Small defects, internal voids, and other defects can be recognized stably in a short time. That is, when a beam of P-polarized component is made incident on the surface of the transparent resin portion of the semiconductor element at an angle of polarization angle and irradiated, the reflected component on the normal transparent resin surface is almost 0, and the irradiated beam is entirely transmitted. Therefore, the beam applied to the normal transparent resin portion surface is always a totally transmitted beam having no reflection component. As a result, since the normal reflected light of the transparent resin portion is 0, the output level of the electric signal obtained at the light receiving portion is always 0 level.

On the other hand, in the case of a defect transparent resin portion where the transparent resin portion has irregularities such as cracks, scratches, and cracks on the surface, the incident angle is no longer the polarization angle due to the irregularities of the irregularities, and it depends on the irregular shape. A beam having a different incident angle and having a reflection component due to the influence of light diffraction etc. on the uneven surface. Further, since the void inside the transparent resin is simply a defect on the unevenness, it becomes a beam having a reflection component by the same phenomenon as described above. That is, when the beam is applied to the defective portion of the uneven surface, diffuse reflection light is generated, so that the output obtained at the light receiving portion becomes larger than a certain reference level. Therefore, by determining the presence or absence of a defect in the transparent resin on the basis of the output level of the electric signal in the light receiving unit, it is possible to stably determine a minute defect and a void inside the resin in a short time. Further, since the shape of the beam emitted by the light emitting unit is a line beam having a long vertical direction and the beam line length is variable by the slit, it is possible to emit a beam corresponding to various sizes of the transparent resin portion. In the light receiving part, an elliptical reflecting mirror is provided to collect the reflected light diffusely reflected from the surface of the transparent resin defect part and the uneven surface such as voids inside the transparent resin, and the light receiving part installed at the focus of the elliptical reflecting mirror. The diffuse reflection light having a wide incident angle, which is collected by the elliptical reflecting mirror by the hemispherical wide-angle lens in the light receiving part, is collected by the light receiving element, so that defects of minute unevenness and minute Even a weak reflected light from a void or the like can be set to a level higher than a certain reference level.

In the light receiving section, the output level of the electric signal output from the light receiving element is detected by the reference level comparison circuit,
By comparing with the reference level and determining the presence or absence of a defect in the transparent resin portion based on the comparison result, by setting the size of this reference level to a level corresponding to the size of the defect shape, The size of an arbitrary defect shape can be designated by the light emitting portion and the light receiving portion of. That is, it is possible to discriminate only the concave and convex defective portions that affect the reliability and characteristics of the sealed semiconductor element. In addition, the light receiving part has an interference filter with a sensitivity wavelength bandwidth that approximately corresponds to the peak wavelength width of the light source of the light emitting part, and is attached to the front surface of the light receiving element of the light receiving part. Is cut, and false recognition or judgment due to ambient light does not occur. That is,
Since only the light flux of the light source is transmitted to the light receiving element, a stable semiconductor element inspection device can always be obtained.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing the configuration of a semiconductor device inspection apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the semiconductor device inspecting apparatus according to the present embodiment includes a light emitting diode section 1a to be inspected,
A holder part 2 for linearly arranging the transparent resin part 1c of the semiconductor element 1 having the lead part 1b and the transparent resin part 1c, a moving line 3 for moving the transparent resin part 1c together with the holder part 2, and a transparent line. Light beam 4 on resin part 1c
a, a light emitting section 4 for irradiating a, a light receiving section 5 for receiving a beam 4b which is a diffuse reflection light of the light beam 4a emitted from the light emitting section 4, and an elliptical reflecting mirror 6 for focusing the reflected light on the light receiving section 5. It has and. The holder portion 2 is entirely black-anodized to prevent reflection.
It should be noted that θ _B is a polarization angle at which the light beam 4a enters the transparent resin portion 1c.

The operation of the semiconductor device inspection apparatus according to this embodiment having the above structure will be described below.

As shown in FIG. 1, the light emitting portion 4 is installed at an angle having a predetermined polarization angle θ _B , and a holder for arranging the transparent resin portions 1c on the moving line 3 in a straight line. Part 2 is installed. Therefore, the holder 2 is moved in the arrow A direction by the moving line 3.
The light emitting part 4 irradiates the transparent resin part 1c with the light beam 4a at an angle equal to the polarization angle θ _B at predetermined time intervals. The beam shape of the light beam 4a is parallel to the longitudinal direction of the transparent resin part 1c. It has a long line beam shape (longitudinal direction). Further, the light receiving section 5 receives the diffuse reflected light beam 4b due to the defective surface such as the uneven portion of the transparent resin section 1c. Based on the output level of the video signal obtained by photoelectrically converting the diffuse reflected light beam 4b, the presence or absence of the surface shape defect of the transparent resin portion 1c, the internal void, etc. is determined. Note that the diffuse reflected light 4b
Is a reflected light having any angle due to the uneven shape, and becomes a light flux having a spread.

Next, the light emitting section 4 will be described with reference to the drawings. 2 is a side sectional view thereof, and FIG. 3 is a front view thereof.

As shown in FIG. 2, the light emitting section 4 includes a light emitting element 40 made of a visible semiconductor laser, and a pulse driving section 41 having a circuit for pulse driving the light emitting element 40.
And a collimator optical system 42 for collimating the elliptical light beam 40a emitted from the light emitting element 40 to obtain a collimated beam 40b and a P-polarized beam 40c for transmitting only the P-polarized component from the collimated beam 40b. P polarizing plate 43, which is a dichroic polarizing plate, and lenses 44a and 44
Inverse Galileo type beam expander optical system 4
4 and P by changing the beam width of the P polarized beam 40c arbitrarily.
A rectangular beam diameter variable slit 45 for obtaining a polarized parallel elliptical beam 40d, a linear line slit 46 that can be exchanged into an arbitrary shape, a holder 47 for fixing each of these components, and a power supply line 48, And a frame 49.

The operation of the light emitting portion having such a structure will be described. The light emitting element 40 is repeatedly turned on and off by the pulse driving section 41 to produce the pulsed elliptical light beam 4
0a is emitted. Further, the elliptical light beam 40a emitted from the light emitting element 40 is diffracted by the difference in the horizontal width and the vertical thickness of the active layer of the light emitting element 40.
It is an elliptical beam having a long diameter in the longitudinal direction with a beam diameter of about 1: 3 to 4. Therefore, when the parallel beam 40b obtained by collimating the elliptical beam having a long vertical direction by the collimator optical system 42 is incident on the P polarizing plate 43, the light emitting element 4
The elliptical light beam 40a of 0 has both P-polarized light component and S-polarized light component, but only the light flux of P-polarized light component is transmitted by the P-polarizing plate 43 (P-polarized light beam 40c), and the vertical direction is expanded by the expander optical system 44. Further expanded. That is, P
An unnecessary portion of the polarized beam 40c is cut by the beam diameter variable slit 45 so as to have an arbitrary beam width in the vertical direction (vertical direction). The P-polarized beam 40c, which is cut so that the vertical direction has an arbitrary beam width, is expanded at an arbitrary magnification by the lenses 44a and 44b of the beam expander optical system 44 to become a P-polarized parallel elliptical beam 40d. . The P-polarized parallel elliptical beam 40d is emitted from the light emitting unit 4 as the light beam 4a.

Lens 4 of beam expander optical system 44
When the focal length of 4a is f _a and the focal length of the lens 44b is f _b , the magnification M of the beam expander optical system 44 is expressed by the following equation (2).

M = W ′ / W = f _b / f _a (2) where W ′: radius of emitted light W: radius of incident light This magnification M (= f _b / f _a ) Is greater than 1,
P-polarized parallel elliptical beam 4 with an arbitrary elliptical beam width
Vertical direction of 0d (the same direction as the longitudinal direction of the transparent resin portion 1c)
Can be expanded. If the magnification is fixed to M = 5,
P-polarized component parallel elliptical beam 40 in which horizontal width: vertical width = 1: 2 is set by the beam diameter variable slit 45.
In the case of d, the beam becomes an elliptical beam in which the horizontal width: vertical width = 1: 10 is considerably long in the vertical direction. Further, if the horizontal width: vertical width = 1: 3 is set by the beam diameter variable slit 45, the P-polarized parallel elliptical beam 40d can be changed to an elliptical beam having a horizontal width: vertical width = 1: 15 with a longer vertical direction. it can. That is, the beam width can be changed as an elliptical shape magnified by M times of the beam expander optical system 44 only by arbitrarily changing only the vertical direction (vertical direction) by the beam diameter variable slit 45.

As described above, the light emitting section 4 collimates the elliptical light beam 40a emitted intermittently from the light emitting element 40 driven by the pulse drive circuit 41 by the collimator optical system 42, and the P polarizing plate 43. The P-polarized light component of the P and S polarized light components of the elliptical light beam 40a that has been collimated by P is transmitted, and the vertical width is expanded by the beam expander optical system 44 as a parallel beam 40b of only the P-polarized light component. The polarized parallel elliptical beam 40d is emitted. Since the vertical width of the parallel beam 40b can be adjusted by the slit 45, the ellipticity of the P-polarized parallel elliptical beam 40d expanded by selecting an arbitrary incident light vertical width can be adjusted.
Further, the beam (light beam 4a) finally emitted from the light emitting unit 4 is cut into unnecessary portions so as to be linear by the line slit 46 having a linear rectangular shape. That is, the P-polarized parallel elliptical beam 40d is converted by the line slit 46 into
A linear light beam 4a having a long vertical direction (vertical direction) is finally emitted from the light emitting unit 4. Thereby, the light beam 4a having a desired vertical width can be emitted according to the size of the transparent resin portion 1c.

The light emitting section 4 is provided with a light beam 4 emitted therefrom.
Although the angle θ _{B at} which a enters the transparent resin portion 1c is equal to the polarization angle, in this case, assuming that the refractive index n of the transparent resin portion 1c is, for example, n = 1.55,
The Fresnel reflection coefficient r _p of only the P polarization component is calculated by the following equation (3).
It is represented by.

R _p = (n ₂ cosθ ₁ −n ₁ cosθ ₂ ) / (n ₂ cosθ ₁ + n ₁ cosθ ₂ ) = {tan (θ ₁ −θ ₂ )} / {tan (θ ₁ + θ ₂ )} ... (3) where n ₁ : refractive index in air (= 1.00) n ₂ : refractive index of transparent resin (= 1.55) r _p : reflection coefficient of p-polarized component θ ₁ : incident angle θ ₂ : Refraction angle When θ ₁ + θ ₂ = π / 2 in formula (3), formula (3)
Is r _p = 0. That is, the reflection coefficient becomes 0 (r _p
= 0) there is an incident angle θ _B (polarization angle). This θ _B (polarization angle) can be obtained by the following equation (4) by using the Snell's law of refraction.

Tan θ _B = n ₂ / n ₁ (4) Therefore, the polarization angle in this case is 57 ° according to the equation (4).
Therefore, if the incident angle of the light beam 4a is set in the vicinity of this angle, the reflected light from the surface of the transparent resin portion 1c becomes almost impossible, the reflected light becomes almost 0, and the light beam incident with this polarization angle is 4a is almost all transparent resin part 1
It is in a state of transmitting c.

Next, the light receiving section 5 will be described with reference to the drawings. FIG. 4 is a side sectional view thereof.

As shown in FIG. 4, the light receiving portion 5 has an elliptical reflecting mirror 6 having an elliptical shape on the upper side, and has a hemispherical shape for receiving a beam 4b installed near the focal point of the elliptic reflecting mirror 6. Wide-angle lens 50, an interference filter 51 having a spectral half-value width slightly larger than the spectral half-value width of the peak wavelength of the light beam 4a emitted from the light-emitting unit 4, and a light-receiving element that is a pin photodiode that photoelectrically converts reflected light. 52, a drive unit 53 having a circuit for operating the light receiving element 52, a holder 54 for fixing each component, an output level of an electric signal output from the light receiving element 52, and an electric signal equal to or lower than a predetermined reference output level. Based on the electric signal output from the reference level threshold circuit 55, and the defect due to the uneven surface or the void surface of the transparent resin portion 1c. And a determination circuit 56 for determining the presence or absence of.

The elliptic reflecting mirror 6 converts the diffuse reflection light (beam 4b) reflected from the defective surface due to the voids inside the resin and the uneven cracks or chips on the surface of the transparent resin portion 1c into a hemispherical wide-angle lens. It is for collecting light. The interference filter 51 is set in the following half width range in consideration of the characteristic variation of the spectrum half width of the peak wavelength of the light source of the light emitting unit 4. If the peak wavelength range of the light source is set to λ = 650 (nm) and the reflectance R for cutting wavelength components other than this is set to R = 0.9, the relationship of the following expression (5) is established.

W = (1−R) λ / πmR ^1/2 (5) where w: half width m: order Therefore, the half width is more than 27 nm for the peak wavelength of 650 nm. Interference filter 51 with slightly larger half width
By using, it is possible to perform wavelength selection according to the peak wavelength range of the light source, and it is possible to almost cut other wavelength bands. That is, the light in the wavelength band different from that of the light beam 4a emitted from the light emitting unit 4 hardly passes through the light receiving unit 5. Therefore, it is possible to prevent the light receiving element 52 from outputting an erroneous output due to ambient light or the like.

Further, the incident angle of the beam 4b which is the diffuse reflection light collected by the elliptical reflecting mirror 6 has a large angle of view, and the outgoing light reflected and condensed by the elliptical reflecting mirror 6 also has a large angle of view. Therefore, when viewed from the light receiving surface of the light receiving element 52 installed in the light receiving section 5, the opening is very large.
Therefore, in the beam 4b that is incident in a large angle range according to the cos4 law, the image plane intensity received by the light receiving element 52 is proportional to the fourth power of cos as the angle of view incident on the light receiving element 52 increases. It gets smaller.

A hemispherical wide-angle lens 50 is used in order to avoid a large reduction in the received light intensity due to the cos fourth power law. As shown in FIGS. 5A and 5B, the wide-angle lens 50 causes the beam 4b, which is diffuse reflected light having a large angle of view, collected by the elliptical reflecting mirror 6, to be reflected on the light receiving surface of the light receiving element 52 in a small image. Since the light can be condensed at an angle, it is possible to suppress a decrease in the light receiving level of the light receiving element 52 due to the cos fourth law. As an example, y ′ = fθ (6) However, if an fθ lens or the like where y ′: image height θ: angle of view f: focal length is used, the image intensity at which light is received is halved. The angle is 58 degrees, and the angle of view at which the received light intensity is halved without the correction lens is 32 degrees, so that it is possible to stably receive light up to a field angle that is 26 degrees wider than this.

Further, the reference level threshold circuit section 54 for outputting the reference level sets a predetermined reference level, and the light receiving element 52 below the output level with the value of the reference level as a threshold value.
The output level of is cut. This predetermined reference level is stored in a memory (not shown) built in the reference level threshold circuit section 54 according to the size of the uneven shape on the surface of the transparent resin portion 1c and the size of the void shape inside the transparent resin portion 1c. A reference level, which is a threshold value, can be set according to the size of the defect shape (uneven surface, void, etc.) surface of the portion 1c. In addition, the discrimination circuit unit 55 binary-codes the output signal of the reference level threshold circuit unit 54, so that the transparent resin unit 1
It is determined whether the surface and inside of c are normal or whether a defective surface exists, and the result is output. The discrimination circuit unit 55
May perform processing on the signal by means such as AND logic.

Although the reference level threshold circuit section 55 and the discrimination circuit section 56 are incorporated in the light receiving section 5 in FIG. 4, they may be separated from each other and used.

The operation of the light receiving section 5 constructed as described above will be described below. The light beam 4b which is the diffuse reflection light collected by the elliptical reflecting mirror 6 and the hemispherical wide-angle lens 50 is wavelength-selected by the interference filter 51, and only the beam 4b reflected from the defective surface of the transparent resin portion 1c is selected. Is transmitted and is condensed on the light-receiving surface of the light-receiving element 52 installed at the focal point of the hemispherical wide-angle lens 50 to obtain a photoelectrically converted pulsed electric signal. Then, the reference level threshold circuit 54 that generates a predetermined threshold level of the electric signal compares the output level of the electric signal from the light receiving element 52 with the threshold level, and only the output exceeding this threshold is determined by the judgment circuit. Binary encoding by 55 or AND
Display output with logic etc. As a result, it is possible to determine whether the irregular defect surface on the surface of the transparent resin portion 1c to be inspected and the state of internal voids are normal or defective.

Next, a method for inspecting the defect state of the transparent resin portion of the semiconductor element using the semiconductor element inspection apparatus of this embodiment will be described with reference to FIGS.

FIG. 6 is a diagram showing a state in which a line beam is irradiated at the time of inspecting a transparent resin portion by using the semiconductor device inspecting apparatus of this embodiment. In FIG. 6, line beam locations 60, 61, and 62 are locations where the same light beam 4a (line beam) emitted from the light emitting unit 4 shown in FIG. 1 is emitted. FIG. 7 is a waveform diagram showing the output of the light receiving portion 5 when inspecting the transparent resin portion using the semiconductor element inspection apparatus of this embodiment. 8 to 10 are side views showing a method of inspecting a transparent resin portion using the semiconductor device inspection apparatus of this embodiment. FIG. 11 is a waveform diagram showing the output of the light receiving portion 5 when inspecting the transparent resin portion using the semiconductor element inspection apparatus of this embodiment. FIG. 12 shows the light emitting unit 4 of the semiconductor device inspection apparatus of this embodiment.
Pulse driving unit 41 for directly pulse driving the light source of
5 is a waveform diagram showing the output of FIG. The same reference numerals as those used in the above figures denote the same configurations.

First, a case where the transparent resin portion 1c encapsulating the semiconductor element has a normal shape will be described with reference to FIGS. It is assumed that when the light beam 4a emitted from the light emitting section 4 is directly photoelectrically converted by the light receiving section 5, the waveform shown in FIG. 7 is obtained.

As shown in FIG. 6, the light beam 4a from the light emitting portion 4 is moved from the left end of the holder 2 to the transparent resin portion 1c by moving the holder 2 fixing the transparent resin portion 1c in the direction of arrow A. It moves continuously to the left end, and then to the right end. The light beam 4a is sequentially irradiated from the line beam spot 60 to the line beam spot 62. Since the entire surface of the holder 2 is black-anodized by the light beam 4a, the reflected light from the holder 2 does not occur. When the transparent resin portion 1c is irradiated with the light beam 4a, the light beam 4a is a beam of only P-polarized component, and as shown in FIG.
Since it is incident on c at the polarization angle θ _B , the reflection coefficient becomes 0 from the Fresnel reflection coefficient equation (3), and the transparent resin portion 1c
There is almost no reflected light that is reflected from the surface or inside the. That is, the irradiated light beam 4a is entirely transmitted. Therefore, as shown in FIG. 7, since a waveform that exceeds the threshold level P is not generated, if the output signal is binary-coded by the determination circuit unit 55, all 0-coded output results are obtained.

Next, since the lead portion 1b and the light emitting diode portion 1a, which are sealed by the transparent resin portion 1c of the semiconductor element 1, have a metal surface and a mirror surface, the case where the light beam 4a is irradiated is shown in FIG. As shown in FIG. 3, the angle of incidence of the reflected light 4c is considerably large because the light is reflected at the same angle as the angle of incidence according to the Snell's law of reflection, and the elliptical reflecting mirror 6 of the light receiving unit 5 is installed. It does not enter any part. That is, since the elliptical reflecting mirror 6 is integrated with the light emitting unit 4, the structure is such that only the reflected light returning toward the light emitting unit 4 can enter the elliptic reflecting mirror 6 portion. Therefore, since it does not enter the light receiving unit 5, it is not detected by the light receiving unit 5.

As described above, if the shape of the transparent resin portion 1c is normal, all the light flux (beam) of only the P-polarized component incident on the transparent resin portion 1c at the polarization angle passes through the transparent resin portion 1c. Since no reflected light is generated, the light receiving unit 5
There is no beam incident on. Therefore, as shown in FIG. 7, the output signal of the electric signal detected by the light receiving unit 5 exhibits a waveform far below the threshold level P, and the discrimination circuit unit 56.
When binary-coded by, all codes are 0.

Next, the case where the transparent resin portion 1c has a defective shape will be described with reference to FIGS. 6, 10 and 11. It is assumed that the transparent resin portion 1c has a defective shape such as irregular cracks and chips on the surface.

As shown in FIG. 6, by moving the transparent resin portion 1c fixed to the holder 2 in the direction of arrow A, the light beam 4a emitted from the light emitting portion 4 is moved to the holder 2
From the left end of the transparent resin portion 1c to the left end of the transparent resin portion 1c, and continuously moves toward the right end thereof for irradiation. At this time, if the surface of the transparent resin portion 1c has irregular cracks, appearance defects due to chipping and defects due to internal voids, the light beam 4a irradiated on the irregular surface of the defective portion is no longer normal. The light is not incident at the polarization angle θ _B , and the reflected light is generated. Moreover, since the uneven surface is very rough, the irradiated light beam 4a is diffusely reflected. Furthermore, since the uneven surface also has the effect of diffracting light, the reflected light on the uneven surface diffuses and spreads very widely. Therefore, in the case where there is an uneven defect surface, diffuse reflected light is generated as shown in FIG. 10, resulting in innumerable beams 4b incident on the elliptical reflecting mirror 6 installed on the light emitting unit 4 side. As a result, the beam 4b that is the diffuse reflection light that has entered the elliptical reflecting mirror 6 of the light receiving unit 5 is condensed by the elliptic reflecting mirror 6, passes through the wide-angle lens 50 and the interference filter 51, and is condensed on the light receiving element 52. . Therefore, the beam 4b which is the diffuse reflection light photoelectrically converted by the light receiving element 52
As shown in FIG. 11, the electric signal output of No. 2 becomes a level exceeding the threshold level P. Therefore, when binary coding is performed by the discrimination circuit unit 55, only the defective portions having concave and convex portions are displayed with an output of 1, which is normal. Since the code is different from that of the transparent resin portion 1c, it can be determined that it is defective.

Further, since the void inside the transparent resin portion 1c is generated by the air layer entering inside when the resin is cured, the void portion having the air layer is an uneven surface. Therefore, even if the surface of the transparent resin portion 1c is normal, if the void is inside, the diffuse reflection light 4b is generated on the void surface, and the diffuse reflection light 4b is transmitted through the transparent resin portion 1c and enters the light receiving portion 5, This will give the same result as the irregularities on the surface. That is, when the discrimination circuit unit 55 performs binary coding, the output display of 1 is obtained, and the normal transparent resin portion 1 is displayed.
Since the code is different from c, it can be determined to be defective. For reference, FIG. 12 is a diagram showing the output of the pulse driving unit 41 for directly pulse-driving the light source of the light emitting unit 4.

As described above, according to the embodiment, the light emitting section 4 causes the transparent resin section 1c encapsulating the semiconductor element 1 to enter the transparent resin section 1c at the polarization angle of the incident angle θ _B , and the light beam of only the P polarization component is emitted. It is possible to stably determine the presence or absence of the shape defect of the transparent resin portion 1c based on the output level of the electric signal obtained by photoelectrically converting the light by the light receiving portion 5 depending on the presence or absence of the reflected light from the transparent resin portion 1c. That is, the transparent resin part 1 having a normal shape
Since c is a plane whose surface and internal state are not uneven, the P-polarized component beam 4 incident at the polarization angle θ _B
As can be seen from the Fresnel reflection coefficient formula (3), the beam 4b, which is the reflected light of a, is in a state in which the reflected light does not occur at all. Therefore, since all the light beam 4a passes through the transparent resin portion 1c, no reflected light that can be received by the light receiving portion 5 is generated, and the electric signal waveform of the photoelectrically converted output has an output result of 0 as shown in FIG. On the other hand, when an uneven defect is generated on the surface and inside of the transparent resin portion 1c, a beam 4b which is a diffuse reflection light reflected from the defect surface of the uneven surface is generated,
A beam 4b that is reflected light is generated with respect to the light beam 4a from the light emitting unit 4.

Therefore, when the beam 4b which is the diffuse reflection light received by the light receiving section 5 is photoelectrically converted, the electric signal waveform has an output result of 1 which exceeds the threshold level P as shown in FIG. Therefore, by determining the presence or absence of a defective shape of the transparent resin portion 1c based on the output level of the electric signal obtained by the light receiving portion 5, the work size and the number of scanning lines of the television camera are limited as in the conventional case. Even a minute uneven shape can be detected without any problem. Further, unlike the conventional case, even if the light emitting diode 1a and the transparent resin portion 1c facing the lead portion 1b have a defect, there is no possibility that a portion that cannot detect the defect is generated. Further, since the threshold level can be set arbitrarily, if there is a defect that exceeds the size of the shape defect in question, it can be designated as a defect. That is, a very minute product which has no problem in reliability and characteristics given to a semiconductor element can be treated as a normal product. Further, the shape size of the defective surface can be designated according to the size of the transparent resin portion 1c. Therefore, the size of the work, that is, the size of the transparent resin portion 1c is not limited, and stable determination can be performed.

The light beam 4 emitted by the light emitting unit 4
By changing the shape of a to an arbitrary elliptical shape having a wide width in the direction parallel to the longitudinal direction of the transparent resin portion 1c by the slit 45 and varying the interval thereof, the width of the light beam 4a can be varied. The light beam 4a corresponding to the size of the transparent resin portion 1c can be emitted. Further, in the light receiving section 5, the reference level threshold circuit section 54 compares the output level of the electric signal output from the light receiving element 52 such as a pin photodiode with the threshold level, and the discrimination circuit section 55 outputs the result as a binary value. By encoding and determining the presence or absence of a shape defect in the transparent resin portion 1c, a simple circuit configuration is sufficient, and since many complicated circuits used for image processing as in the past are not required, the size and weight are reduced. Further, it is possible to realize an excellent semiconductor device inspection apparatus that is advantageous in terms of cost. Further, unlike the conventional case, the inspection time is not greatly affected by the number of pixels, so that the inspection time can be processed at high speed and 100% inspection can be performed. Furthermore, the light emitting unit 4
Since the semiconductor light emitting element is used as the light source of, the erroneous determination caused by the level change of the illumination light unlike the conventional case does not occur. Furthermore, since the semiconductor light emitting element has a much longer life than illumination light, it is always possible to make a stable determination. Further, by providing the interference filter 51 in the light receiving section 5, only the beam 4b which is diffuse reflected light having a wavelength spectrum substantially the same as the wavelength spectrum of the light beam 4a emitted from the light emitting section 4 can be transmitted. The adverse effect due to can be suppressed. In this embodiment, the semiconductor laser is used as the light emitting element 40, but the light emitting element 40 is not limited to this and may be an LED or the like. Further, in the light emitting unit 4, the light emitting element is pulse-driven to repeat the on / off operation and irradiate the pulsed beam, but the invention is not limited to this, and continuous oscillation may be performed by changing the determination means.

[0058]

According to the semiconductor device inspection apparatus of the present invention,
By irradiating the transparent resin part encapsulating the semiconductor element with a line beam of only a specific polarization component of a predetermined size at a polarization angle by the light emitting part, unevenness due to the transparent resin surface and internal voids etc. By receiving the diffuse reflection light reflected from the surface of the shape defect and photoelectrically converting it, the presence or absence of the shape defect of the transparent resin part is determined based on the output level of the electric signal. Even the shape can be stably discriminated. Further, no undetectable transparent resin portion is generated.

Further, the shape of the beam emitted by the light emitting section is a vertically long line beam in the same direction as the longitudinal direction of the transparent resin section, and the beam length is varied by the slit, so that various transparent resin section sizes can be obtained. It is possible to emit a line beam corresponding to. Further, the inspection time is not limited, the processing can be performed in a high-speed inspection time, and an erroneous determination due to the level variation and deterioration of the light source does not occur. Further, in the light receiving section, the reference level threshold circuit section for generating the threshold level compares the output level of the electric signal output from the light receiving element with the threshold level, and based on this result, the presence or absence of the shape defect of the transparent resin section. It is possible to set threshold levels corresponding to the sizes of various shape defects.

Therefore, regardless of the size of the shape defect of the transparent resin, the pair of the light emitting portion and the light receiving portion can stably determine whether the shape of the transparent resin portion is good or bad. Moreover, since a complicated circuit is not required, the device can be made smaller and lighter, which is advantageous in terms of cost. Furthermore, by providing an interference filter that has almost the same half-value width of the wavelength spectrum as the beam emitted from the light-emitting part on the entire surface of the light-receiving element, wavelength selection becomes possible, and other than diffuse reflection light reflected from the shape defect surface of the transparent resin. Since the disturbance light of 2 cannot pass through the interference filter, it does not enter the light receiving element. Therefore, it is possible to suppress the adverse effect of ambient light.

[Brief description of drawings]

FIG. 1 is a side view of a semiconductor device inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a light emitting portion according to an embodiment of the present invention.

FIG. 3 is a front sectional view of a light emitting portion of a semiconductor device inspection apparatus according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view of a light receiving portion of a semiconductor device inspection apparatus according to an embodiment of the present invention.

FIG. 5 is a diagram showing focusing of light on a light receiving portion of a semiconductor device inspection apparatus according to an embodiment of the present invention.

FIG. 6 is a diagram showing line beam irradiation at the time of inspecting a transparent resin portion using a semiconductor element inspection apparatus according to an embodiment of the present invention.

FIG. 7 is a waveform diagram showing the output of the light receiving portion when inspecting the transparent resin portion using the semiconductor element inspection device according to the embodiment of the present invention.

FIG. 8 is a side view showing a method for inspecting a transparent resin portion using a semiconductor element inspection apparatus according to an embodiment of the present invention.

FIG. 9 is a side view showing a method for inspecting a transparent resin portion using a semiconductor element inspection apparatus according to an embodiment of the present invention.

FIG. 10 is a side view showing a method for inspecting a transparent resin portion using a semiconductor element inspection apparatus according to an embodiment of the present invention.

FIG. 11 is a waveform diagram showing the output of the light receiving portion when inspecting the transparent resin portion using the semiconductor element inspection device according to the embodiment of the present invention.

FIG. 12 is a waveform diagram showing an output of a pulse driving unit for directly pulse-driving the light source of the light emitting unit of the semiconductor device inspection apparatus according to the embodiment of the present invention.

FIG. 13 is a side view of a conventional semiconductor device inspection apparatus.

FIG. 14 is a diagram showing image output by a conventional semiconductor device inspection apparatus.

FIG. 15 is a side view of a conventional semiconductor device inspection apparatus.

FIG. 16 is a diagram showing image output by a conventional semiconductor device inspection apparatus.

FIG. 17 is a side view of a conventional semiconductor device inspection apparatus.

FIG. 18 is a diagram showing image output by a conventional semiconductor device inspection apparatus.

[Explanation of symbols]

 1 semiconductor element 1a light emitting diode (light emitting diode) section 1b lead section 1c transparent resin section 2 holder section 3 moving line 4 light emitting section 4a beam 4b beam 5 light receiving section 6 elliptical reflecting mirror 40 light emitting element 40a elliptical light beam 40b parallel beam 40c P Polarized beam 40d P-polarized parallel elliptical beam 41 Pulse drive unit 42 Collimator optical system 43 P polarizing plate 44 Beam expander optical system 44a Lens 44b lens 45 Beam diameter variable slit 46 Line slit 47 Holder 48 Power line 49 Frame body 50 Wide angle lens 51 Interference filter 52 Light receiving element 53 Drive section 54 Fixing holder 55 Reference level threshold circuit section 56 Discrimination circuit section 60 Line beam location 61 Line beam location 62 Line beam location 81 Semiconductor element 81a Light emitting die Over de (light emitting diode) unit 81b lead portion 81c transparent resin section 82 fixed worktable 83 light diffusing plate 84 progressive scan television camera 85 the illumination light 86 diffused light

Claims (5)

[Claims] 1. A holder part for linearly arranging the transparent resin part of a semiconductor element to be inspected, which has a light emitting diode part, a lead part and a transparent resin part, and the transparent resin part is moved together with the holder part. A moving line, a light emitting portion that irradiates the transparent resin portion with the first beam, a light receiving portion that receives a second beam that is a diffuse reflection light of the first beam emitted from the light emitting portion, and a light reflected by the light receiving portion. And an elliptical reflecting mirror for focusing the semiconductor device. 2. The semiconductor element according to claim 1, wherein the light emitting portion is provided at a position where the first beam from the light emitting portion is incident on the transparent resin portion of the semiconductor element to be inspected at a polarization angle. Inspection device. 3. The semiconductor device inspection apparatus according to claim 1, further comprising a holder portion which is entirely black-anodized. 4. A light emitting element, a pulse driving section having a circuit for pulse driving the light emitting element, and a collimator optical system for collimating an elliptical light beam emitted from the light emitting element to obtain a parallel beam. A P-polarizing plate that transmits only a P-polarized component from the parallel beam to emit a P-polarized beam, a beam expander optical system including a lens group, and a beam width of the P-polarized beam are changed to obtain a P-polarized parallel elliptical beam. 2. The semiconductor device inspection apparatus according to claim 1, further comprising a light emitting unit having a rectangular beam diameter variable slit and a linear line slit for exchanging a P-polarized parallel elliptical beam into an arbitrary shape. 5. A hemispherical wide-angle lens having an elliptical reflecting mirror having an elliptical shape formed above the light receiving portion, the semi-spherical wide-angle lens being installed near the focal point of the elliptic reflecting mirror, and an interference filter. A light receiving element that receives the second beam that is reflected light and performs photoelectric conversion, a drive unit that includes a circuit that operates the light receiving element, an output level of an electric signal output from the light receiving element, and a predetermined reference output level or less 2. The semiconductor according to claim 1, further comprising: a reference level threshold circuit section that cuts the electric signal of 1. and a discrimination circuit section that outputs a discrimination signal based on the electric signal output from the reference level threshold circuit. Element inspection device.