JPH0755711A - Semiconductor-device inspecting apparatus - Google Patents

Abstract

PURPOSE:To provide an inspecting apparatus, which can inspect the surface and four side surfaces of a diced semiconductor chip with an optical inspecting device and has a simple constitution. CONSTITUTION:An inspection table 8, which sucks and holds a semiconductor chip 3 conveyed from the upper surface of an expanding tape 2 with a sucking collet 7 of a conveying means 6 on an upper surface 10, is provided. An optical inspecting device 5, which inspects the presence or absence of flaws, cracks and the like on the surface and four side surfaces of the semiconductor chip 3, is provided at the upper side of the inspection table 8. The inspection table 8 is supported with a rotary supporting means comprising a first arm 13, a second arm, a driving shaft and first and second driving mechanisms. The table can be turned about 90 deg. back and forth and right and left with the first and second rotary axial lines of 0 and 01 as the centers with the vertical state as the reference. Thus, the surface and four side surfaces of the semiconductor chip 3 can be arranged toward the optical inspecting device 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device inspection apparatus.

[0002]

2. Description of the Related Art In the process of manufacturing semiconductor devices such as FETs and ICs, dicing is performed while a silicon wafer on which elements and circuits are formed is adhered to an expanding tape, and a large number of semiconductor devices (hereinafter referred to as semiconductor chips). Is created).

In this way, the surface of the semiconductor chip has to be rejected because dust, foreign matter, scratches, defects in metal wiring, etc. attached to the surface of the manufactured semiconductor chip must be rejected. A visual inspection is being conducted.

Conventionally, this inspection is carried out by optical means while the semiconductor chip is diced and still adhered to the expanding tape. Referring to FIGS. 5 to 7, in FIG. 5, a silicon wafer 1 on which elements and circuits are formed is adhered to the upper surface of an expanding tape 2 and diced with a diamond blade (not shown) to form a large number of semiconductor chips 3 groups. The state in which the is formed is shown.

To optically inspect the surface of the semiconductor chip 3, first, as shown in FIG. 6, the peripheral edge of the expand tape 3 is pulled outward to expand the tape surface. As a result, a slight gap 4 is formed between the semiconductor chips 3, and the edges of the semiconductor chips 3 can be clearly distinguished.

Next, the optical inspection device 5 arranged above the semiconductor chip 3 inspects the surface of the semiconductor chip for scratches or the like. The optical inspection device 5 is composed of, for example, a device provided with a light source and an optical sensor such as a CCD camera and an image pickup tube, and emits inspection light to the surface of the semiconductor chip 3 and analyzes the reflected light.

This optical inspection device is highly accurate, and the inspection is performed as follows. For example,
In the case of a FET, dust, foreign matter, etc. on the surface of a semiconductor chip are inspected by scattering the light distribution in the reflection direction and sensing by light diffraction to identify it. Also, dirt on the chip surface,
Roughness and other inspections are performed by sensing and identifying the distribution of the amount of reflected light of the light utilizing the difference in reflectance. In addition, the discrimination of the boundary between the inorganic substance and the organic substance for the inspection of defects of the metal wiring,
Sensing is performed by utilizing the difference in fluorescence due to ultraviolet rays, and the identification is performed.

As described above, the optical inspection device itself has a very high precision, and therefore, the appearance defect on the surface of the semiconductor chip can be inspected with a very high precision. Further, an automatic inspection device using this optical technique has already been developed and put into practical use.

However, an inspection device for scratches and cracks on the side surface of the semiconductor chip has not yet been developed, and in reality, defects such as scratches on the side surface of the semiconductor chip have not been inspected.

That is, semiconductor chips are usually formed by mechanically cutting a silicon wafer with a diamond blade, and at the time of this cutting, scratches and cracks are often generated on the semiconductor surface. Although a semiconductor chip having scratches on its side surface has low mechanical reliability, these products have been accepted as good products in the past.

The present inventor carried out a mounting process of a defective semiconductor chip having a scratch or a crack on its side surface and a non-defective semiconductor chip having no scratch, and conducted a reliability test under the same conditions. As a result, in each of the mechanical reliability test (constant acceleration test, vibration test), heat cycle test, and thermal shock test, a defect occurred on the semiconductor chip having scratches on its side surface. For example, a temperature cycle test of −65 ° C.
In the test at 150 ° C. and 1000 cycles, about 1% of defects occurred.

As described above, it is clear from the results of various tests that the semiconductor reliability of the semiconductor chip having scratches, cracks, etc. on its side surface is reduced to less than half. To solve this problem, the side surface of the semiconductor chip may be optically inspected like the surface.

As an inspection method in this case, for example, FIG.
It is conceivable to inspect by irradiating the four side surfaces of each semiconductor chip 3 with inspection light while inclining the arrangement angle of the optical inspection device 5 in a state in which the semiconductor chip 3 as described above is adhered to the expanded tape 2. .

However, in the above-mentioned inspection method, the semiconductor chips 3 are arranged side by side on the expanding tape 2 and bonded,
Since the semiconductor chips 3 are arranged in the front-rear direction and the left-right direction with a relatively small gap 4 therebetween, it is possible to irradiate a sufficient amount of inspection light from the vertical direction to the side surface of the chip for highly accurate inspection. Have difficulty. Further, in order to move the optical inspection device 5 so as to incline, the supporting mechanism is complicated, which leads to high cost.

[0015]

From the above, the conventional semiconductor chip inspecting apparatus only performs visual inspection of the chip surface, and therefore, semiconductor chips having scratches, cracks, etc. on the side surfaces are regarded as good products. There was a problem.
Further, even if the supporting mechanism of the conventional optical inspection device for the surface of the semiconductor chip is improved to perform side inspection, there are various problems such as the mechanism becoming complicated.

An object of the present invention is to provide a semiconductor device inspection apparatus which solves the above problems.

[0017]

In order to achieve the above object, a semiconductor device inspection apparatus according to the present invention is an inspection table for holding a chip-shaped semiconductor device separated from an expand tape on an upper surface thereof, and this inspection table. It is characterized by a rotation driving means such as a motor for rotating the optical axis about its axis, and an optical inspection device arranged toward the side surface of the semiconductor device held on the inspection table.

Further, the semiconductor device inspection apparatus of the present invention comprises an inspection cable for holding the chip-shaped semiconductor device separated from the expanding tape on the upper surface thereof, and an optical inspection of the semiconductor device arranged downward above the inspection table. The present invention is characterized in that it comprises a device and a rotation support means for rotating the inspection table about 90 ° back and forth and left and right with reference to a state where the axis of the inspection cable is vertical.

The semiconductor device holding means provided on the inspection table may be constituted by a suction collet that guides the tip of a cylindrical hole formed in the inspection table to the upper surface of the inspection table.

Further, it is preferable that a conveying means for adhering the chip-shaped semiconductor devices, which are adhered to the expanding tape, to the inspection table is provided one by one, and the conveying means is provided with an adsorption collet for adsorbing the semiconductor devices.

[0021]

According to the structure of the present invention, a semiconductor device obtained by dicing a silicon wafer whose elements and circuits have been processed into a large number of chips is held on an inspection table, and the inspection table is used to determine its vertical axis. Can be rotated about the vertical axis, or can be rotated to the front, rear, left, and right with respect to the vertical axis, so that the four side surfaces or the four side surfaces and the surface of the semiconductor device can be arranged toward the optical inspection device.
The inspection light reflected from each inspection surface of the semiconductor chip can be smoothly and highly accurately imaged to inspect each surface.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

1 and 2 are explanatory views of an embodiment of a semiconductor chip inspection apparatus according to the present invention, and FIG. 3 is a perspective view of a rotation supporting means of an inspection table.

In FIG. 1, a semiconductor chip 3 that has been diced is adhered to an expanding tape 2, and a gap 4 is formed between the semiconductor chips 3 by expanding the expanding tape 2. In this state,
The semiconductor chips 3 are adsorbed by the adsorption collet 7 forming the tip of the conveying means 6 and conveyed one by one above the inspection table 8. The suction collet 7 has a cylindrical shape, and has a suction port 9 having a tapered diameter at its tip.

The inspection table 8 is arranged at a position slightly away from the place where the silicon wafer is diced, and the suction collet 7 of the transfer means 6 sucks the semiconductor chip 3 into the suction port 9 by vacuum suction. Then, the dicing position and the position of the inspection table 8 can be reciprocated as shown by the arrow.

The inspection table 8 has a table upper surface 10
The table upper surface 10 serves as a holding portion that receives the semiconductor chip 3 conveyed by the suction collet 7 and suction-holds it.

Further, the inspection table 8 is approximately 9 in front and back and left and right around the _first rotation axis O and the second rotation axis O ₁ with reference to the state of FIG. 1 in which the axis is vertically positioned.
It is supported by a rotation support means so that it can rotate 0 °.

The rotation support means is constructed as shown in FIG. 3, for example. In the figure, the first arm 13 extends from both ends of the base portion 8a of the inspection table 8 in a direction perpendicular to the table axis, and both ends of the first arm 13 are attached to both ends of the U-shaped second arm 14. It is supported by the bearing portion 15 formed. A first drive mechanism 16 including a stepping motor or the like is provided at the side end of the second arm 14,
An end portion of the first arm 13 is connected to the first drive mechanism 16 so as to be interlocked and rotatable.

The second arm 14 is supported by a drive shaft 17 penetrating the lower part of the second arm 14 in a direction orthogonal to the first arm 13, and the drive shaft 17 is composed of the same stepping motor as described above. The second drive mechanism 18 is interlockingly connected. The suction hose 20 connected to the lower end of the cylindrical hole 12 (shown in FIG. 1) of the inspection table 8 is pulled out downward through a hole 21 formed in the bottom of the second arm 14.

Therefore, the first and second drive mechanisms 16, 1
When the inspection table 8 is not operated, the inspection table 8 is arranged upward so that the axis is vertical, and the surface of the semiconductor chip 3 is positioned upward, as shown in the left diagrams of FIGS. 3 and 1.

Next, by operating only the second drive mechanism 18, the inspection table 8 is rotated about the drive shaft 17 to the left or right of the inspection table 8 with the vertical state as a reference.
It can be rotated 0 ° (see FIG. 2). At this time,
Semiconductor chip 3 adsorbed on the upper surface 10 of the inspection table 8
The two side surfaces A and B facing each other can be alternately arranged in the vertical direction.

Next, by operating only the first drive mechanism, the inspection table 8 is rotated 90 ° forward and backward with respect to the vertical state with the axis of the first arm as the center of rotation (that is, in the front-back direction of the paper surface of FIG. 1). ), The other two side surfaces C and D (shown in FIG. 3) of the semiconductor chip 3 can be alternately arranged vertically upward.

Above the inspection table 8, a light source and a CCD are provided.
Optical inspection device 5 equipped with optical sensors such as a camera and an image pickup tube
Are arranged vertically downward. The optical inspection device 5 is connected to the quality determination device 5a, inspects the surface and each side surface of the semiconductor chip 3, takes in information on the presence or absence of scratches, cracks, etc., and binarizes the information to obtain a quality determination device. 5
can be output to a.

The operation of this embodiment will be described.

First, the semiconductor chips 3 adhered to the expanding tape 2 shown in FIG. 1 are separated one by one from the tape upper surface to the upper surface 10 of the inspection table 8 by the suction collet 7 and conveyed to the upper surface 10 of the inspection table 8. The suction device (not shown) is operated to suck the semiconductor chip 3 onto the upper surface 10 of the inspection table 8. Next, in this state, as shown in the right diagram of FIG. 1, the inspection light is emitted toward the surface of the semiconductor chip 3 by the optical inspection device 5 to inspect for scratches on the chip surface, adhesion of foreign matter, disconnection, and the like. .

Next, as shown in FIG. 2, the inspection table 8 is rotated left and right (centering around the drive shaft 17 shown in FIG. 3) so that the axis of the inspection table 8 is horizontal, and the semiconductor chip is rotated. The two side surfaces A and B of 3 are alternately positioned upward and the optical inspection device 5 inspects for scratches, cracks, etc. on the side surface of the chip.

Next, the inspection table 8 is rotated around the first arm 13 shown in FIG. 3 so that the other two side surfaces C and D of the semiconductor chip 3 are arranged upward, and the optical inspection apparatus is operated in the same manner as described above. 5 can be checked (this condition is not shown).

In the rotation supporting means shown in FIG. 3, when the inspection table 8 is rotated about 90 ° in the front-rear direction and the left-right direction with respect to the vertically upward position, the position of the semiconductor chip 3 is slightly displaced, If the optical inspection device 5 is arranged above the inspection table 8 by a proper distance, the inspection light irradiating the side surface of the chip can be smoothly incident on the optical inspection device 5 even if the semiconductor chip 3 is slightly displaced. It is possible to inspect scratches, cracks, etc. on the chip side with high accuracy.

Of course, the optical inspection device 5 can be freely provided in accordance with the displacement of the semiconductor chip 3, and the moving mechanism in that case can be constructed very simply. Further, the rotation supporting means of the inspection table 8 may have a structure other than these, and the structure thereof is not limited as long as it is supported so as to be rotatable in the directions of the two axes orthogonal to each other.

The present inventor has already prototyped the device of this embodiment and is still operating it, but the semiconductor chip inspected by this device has not yet had any defects in the reliability test. Moreover, although shipments of bare chips have recently increased, in this case, chips with low mechanical reliability are no longer shipped.

FIG. 5 is a side view of the second embodiment. The configurations of the transporting means 6 and the inspection table 8 in the second embodiment are the same as those in the first embodiment. In the second embodiment, the inspection table 8 is supported rotatably about the vertical axis O ₃ by a motor (not shown) which is a drive mechanism,
In addition, the optical inspection device 5 is arranged horizontally, and the inspection table 8
It is different from the first embodiment in that it is arranged toward the side surfaces A to D of the semiconductor chip 3 held by.

In the second embodiment, the semiconductor chip 3 peeled from the expanding tape 2 by the conveying means 6 is attracted to the upper surface 10 of the inspection table 8 and the inspection table 8 is intermittently rotated about the vertical axis O ₃ . The four side surfaces A to D of the semiconductor chip 3 can be inspected with high precision by the optical inspection device 5.

Further, in the second embodiment, an optical inspection device for inspecting the surface of the semiconductor chip 3 is required separately, but this chip surface inspection is performed by the optical inspection device 5 shown in FIG. Alternatively, it may be provided so as to be inspected by an optical inspection device (not shown) separately arranged above the inspection table 8 in FIG.

[0044]

As described above, according to the present invention, an inspection table having a holding surface for holding a semiconductor device facing upward is rotated around its vertical axis, or approximately 90 ° to the front, rear, left and right with reference to the vertical axis. By rotating, the four side surfaces or the four side surfaces and the surface of the semiconductor device can be positioned toward the optical inspection apparatus, and each inspection surface can be inspected with high accuracy. Moreover, the present invention is a semiconductor device inspection apparatus having a very simple structure and suitable for being incorporated in an automatic inspection line. In particular, GaIC and AsIC are more fragile than SiIC, and are liable to be chipped or cracked on the side surface of the device. Therefore, it is extremely useful to apply the present invention in such a case.

[Brief description of drawings]

FIG. 1 is an explanatory view of a semiconductor chip transportation mode and a chip surface inspection mode according to a first embodiment.

FIG. 2 is an explanatory diagram of an inspection aspect of two side surfaces of a semiconductor chip.

FIG. 3 is a perspective view of a rotation support unit of the inspection table.

FIG. 4 is a perspective view of an inspection table and an optical inspection device.

FIG. 5 is an explanatory view of a semiconductor chip carrying mode and a chip side surface inspection mode according to the second embodiment.

FIG. 6 is a perspective view of a semiconductor chip group on the expanded tape at the end of dicing.

FIG. 7 is a perspective view of the expanded tape of FIG. 5 in an expanded state.

8 is an explanatory diagram of an inspection aspect of a semiconductor chip surface by the optical inspection device in the state of FIG.

[Explanation of symbols]

2 ... Expanded tape, 3 ... Semiconductor chip, 5 ... Optical inspection device, 6 ... Conveying means, 7 ... Adsorption collet, 8 ... Inspection table, 13 ... First arm, 14 ... Second arm, 16
... 1st drive mechanism, 17 ... Drive shaft, 18 ... 2nd drive mechanism.

Claims (6)

[Claims] 1. An inspection table for holding a chip-shaped semiconductor device separated from an expanding tape on an upper surface, a rotation driving means for rotating the inspection table about its axis, and the semiconductor held by the inspection table. An inspection apparatus for a semiconductor device, comprising: an optical inspection apparatus arranged toward a side surface of the device. 2. A carrying means for carrying, one by one, the chip-shaped semiconductor devices adhered to the expanding tape to the inspection table is provided, and the carrying means comprises a suction collet for sucking the semiconductor devices. The semiconductor device inspection apparatus according to claim 1, wherein: 3. An inspection cable for holding a chip-shaped semiconductor device separated from an expand tape on an upper surface, an optical inspection apparatus for the semiconductor device arranged downwardly above the inspection table, and an inspection cable for the inspection cable. An inspection apparatus for a semiconductor device, characterized in that the inspection table is constituted by a rotation supporting means for rotating the inspection table forward and backward and rightward and leftward by approximately 90 ° with reference to a state where the axis is vertical. 4. The rotation support means includes a first arm projecting from the inspection table to both sides in a direction orthogonal to the table axis, and a second arm pivotally supporting both ends of the first arm.
An arm, a drive shaft that supports the second arm and is disposed in a direction orthogonal to the first arm, and a first shaft that is disposed on the second arm and transmits a rotational force to the first arm.
4. The semiconductor device inspection apparatus according to claim 3, comprising a drive mechanism and a second drive mechanism that transmits a rotational force to the drive shaft. 5. The holding means for holding the semiconductor device, which is provided on the upper surface of the inspection table, is constituted by a suction collet that guides the tip of a cylindrical hole provided on the inspection table to the upper surface of the inspection table. The semiconductor device inspection apparatus according to claim 1 or 3. 6. A carrying means is provided for carrying, one by one, the chip-shaped semiconductor devices adhered to the expand tape to the inspection table, and the carrying means comprises a suction collet for the semiconductor devices. The semiconductor device inspection apparatus according to claim 1, wherein the inspection apparatus is a semiconductor device inspection apparatus.