JPH0590366A - Semiconductor chip sorter - Google Patents

Abstract

(57) [Summary] [Purpose] Regardless of the difference in the type of semiconductor chip or the difference in the manufacturing lot of semiconductor wafers, the position, quality, and defects of semiconductor chips can be easily and accurately inspected and selected in a short time. [Structure] Spot illumination devices 5A and 5B for obliquely irradiating spot light onto the upper surface of a semiconductor wafer 3 loaded onto a mounting table 3 while being attached to the upper surface of a wafer sheet 2 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly to a semiconductor chip sorting apparatus for sorting semiconductor chips from a semiconductor wafer.

[0002]

2. Description of the Related Art Conventionally, in an inner lead bonding apparatus for collectively connecting electrodes of a semiconductor chip to inner leads of a film carrier tape, a semiconductor wafer supplied to a mounting table in a state of being stuck on a wafer sheet, Only non-defective semiconductor chips are selected and taken out, the semiconductor chips are positioned on the inner leads of the film carrier tape by a transfer arm, and the electrodes of the semiconductor chips are continuously joined by a bonding tool.

In this inner lead bonding apparatus, each semiconductor chip is inspected and selected as follows. One is the detection of the position for picking up the semiconductor chip by the transfer arm, which is the detection of part of the pattern formed on the surface of the semiconductor chip, and the other is the process upstream of the surface of the semiconductor chip. It is a good / defective selection based on the presence / absence of the defect mark given in step 1 and the presence / absence of a defect in the corner of the semiconductor chip.

Therefore, in the conventional semiconductor chip sorting apparatus of the inner lead bonding apparatus, the semiconductor chip is irradiated with the inspection light from the light source unit of the coaxial drop illuminator, which will be described later in detail, and the reflected light is charged into the charge coupled device (Char.
A ge coupled device) camera (hereinafter referred to as a CCD camera) receives light, the output of the CCD camera is input to an image processing device, processed and displayed on a screen, and the quality is selected from the screen.

[0005]

However, in the conventional semiconductor chip sorting apparatus, the boundary line between the end surface of the semiconductor chip and the wafer sheet may not be identified on the screen, and whether or not the corner of the semiconductor chip is missing. Not only is it impossible to determine the position, but there are also times when the pattern for position detection cannot be detected. Further, in the above-mentioned detection of the defective mark, the image becomes unclear due to the difference in the surface state of the semiconductor chip depending on the type and manufacturing lot of the semiconductor chip. Therefore, a method of adjusting the image processing apparatus each time has been adopted, but it requires skill and is rather labor-intensive, and still cannot be selected when there is a significant difference in surface condition between lots and types.

Therefore, an object of the present invention is to enable easy and accurate inspection / selection in a short time regardless of the type of semiconductor chip or the difference in the manufacturing lot of semiconductor wafers. And to obtain a semiconductor chip sorting apparatus capable of increasing the yield rate of semiconductor chips.

[0007]

SUMMARY OF THE INVENTION According to the present invention, the surface of a semiconductor wafer is irradiated with light by coaxial drop illumination, and the reflected light is detected and processed by an image processing device to detect the position of the semiconductor wafer and detect defects. In the semiconductor chip sorting apparatus for determining the, a spot illuminating device that obliquely irradiates the upper surface of the semiconductor wafer with light from above the semiconductor wafer is provided to make the image of the image processing device clear, and the semiconductor chip type and semiconductor A semiconductor chip sorting device that increases the operating rate of semiconductor manufacturing equipment and the yield rate of semiconductor chips by easily and accurately inspecting and sorting in a short time regardless of the state of the surface of the semiconductor chip depending on the wafer production lot. Is.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the semiconductor chip sorting apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an outline of a semiconductor chip sorting apparatus of the present invention. In FIG. 1, the semiconductor chip 1 is attached to the upper surface of the wafer sheet 2 on the upper surface of the mounting table 3 not shown in detail,
It has been placed now. A half mirror box for coaxial drop lighting is mounted on a mount (not shown) provided above the mounting table 3.
A coaxial drop illuminator 15 and an image processing device 6 which will be described later and are configured by the light source unit 7 and the like described in 12 and the above-mentioned "prior art" are provided.

Of these, the light source unit 7 of the coaxial drop illuminator 15 has a built-in light quantity adjusting device 7a for adjusting the output of a light source (not shown) housed therein.
The half mirror box guide 9A is connected to the tip of the optical fiber 8 connected to the output side of the optical fiber 8 and the further tip of the half mirror box guide 9A is connected to the coaxial drop illumination half mirror box 12. Inside the half mirror box 12 for coaxial drop lighting, a half mirror
11 is stored at an angle of 45 °. An optical lens barrel 12a is connected to the upper surface of the half mirror box 12 for coaxial drop illumination, and the above-mentioned CCD camera 4 is attached to the upper end of the optical lens barrel 12a. The output signal line 4a of the CCD camera 4 is , Is connected to the image processing device 6.

On the other hand, on the upper right side of the mounting table 3, a three-axis driving section and a light source unit 7 (not shown) are mounted on the above-mentioned pedestal. An optical lens guide 9B is attached, a condenser lens box 14 is attached to the tip of the spot illumination condenser lens guide 9B, and a condenser lens 10 is housed inside the condenser lens box 14. ing. An optical fiber 8 is connected to the rear ends of the light source unit 7 and the spot illumination condenser lens guide 9B. These light source unit 7, optical fiber 8, spot illumination condenser lens guide 9B, and condenser lens box 14 are provided. The spot illuminating device 5B is constituted by the above. Similarly, on the upper left side of the mounting table 3, a spot lighting device 5A, which is the same as the spot lighting device 5B, is mounted on a pedestal (not shown) substantially symmetrically with the spot lighting device 5A.

In the semiconductor chip sorting apparatus having the above structure, when detecting the position of the semiconductor chip 1 mounted on the upper surface of the mounting table 3 and sorting the good chips from the defective chips, the conventional semiconductor chips are selected. Similar to the sorting device, the semiconductor chip 1 is irradiated with the inspection light from the half mirror 11 of the coaxial drop lighting device 15, and is emitted from the spot lighting devices 5A and 5B provided on the left and right and is condensed by the condenser lens 10. The semiconductor chip 1 is simultaneously irradiated with the inspection light.

As a result, the light emitted from the half mirror 11 to the semiconductor chip 1 and reflected therefrom enters the CCD camera 4 through the half mirror 11 and the optical lens barrel 12a as in the conventional case.
The output signal of the CCD camera 4 is transferred to the image processing device 6.

On the other hand, the left and right spot lighting devices 5A and 5B
The inspection light that is emitted from the light source unit 7 and enters the condenser lens 10 through the optical fiber 8 and the spot illumination condenser lens guide 9B is condensed by the condenser lens 10 and is applied to the semiconductor chip 1. Part of this reflected light also enters the CCD camera 4 via the half mirror 11.

At this time, while observing the image of the semiconductor chip 1 displayed by the image processing device 6, the amount of light emitted by the light amount adjusting device 7a of each light source unit 7 is adjusted, and the left and right spot illumination light is condensed. By driving the above-described triaxial driving unit that supports the lens guide 9B, the illuminance, angle, and focus of the left and right inspection light with which the semiconductor chip 1 is irradiated are adjusted.

In the semiconductor chip sorting apparatus thus constructed, the inspection light condensed by the condenser lens 10 is obliquely applied to the grooves formed between the respective semiconductor chips 1, so that the grooves Since light shading can be formed on the lower portion and the bottom portion, the image of the image processing device 6 that displays the boundary between the end portion of the semiconductor chip 1 and the wafer sheet 2 can be made clear, and the corner of the semiconductor chip 1 can be sharpened. The display image of the presence or absence of a defect in the part can be made clear as well. Further, even when the type or manufacturing lot of the semiconductor chip 1 changes, the left and right spot lighting devices 5A, 5A, and
By adjusting 5B and the like, it is possible to easily and accurately select a good product or a defective product of semiconductor chips of the same lot that are subsequently supplied.

In the above embodiment, the spot illuminators are provided on the left and right sides of the mounting table 3. However, when there is little variation in the semiconductor wafer surface condition between semiconductor wafer types and manufacturing lots, You may have only one side.

[0017]

As described above, according to the present invention, the surface of a semiconductor wafer is irradiated with light by coaxial drop illumination, the reflected light is detected and processed by an image processing device to detect the position of the semiconductor wafer and discriminate defects. In the semiconductor chip sorting device, the spot illuminating device that obliquely irradiates the upper surface of the semiconductor wafer from above the semiconductor wafer is provided, so that the image of the image processing device is made clear. Semiconductor chip selection that can easily and accurately inspect and sort in a short time regardless of the surface condition of the semiconductor chip depending on the manufacturing lot, and increase the operating rate of the semiconductor manufacturing equipment and the yield rate of the semiconductor chip. The device can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a semiconductor chip sorting apparatus of the present invention.

[Explanation of symbols]

1 ... Semiconductor chip, 2 ... Wafer sheet, 3 ... Mounting table,
4 ... CCD camera, 5A, 5B ... Spot lighting device, 6
... Image processing device.

Claims (1)

[Claims] 1. A semiconductor chip sorter for illuminating the surface of a semiconductor wafer with coaxial drop illumination, detecting the reflected light, processing the image with an image processing device, detecting the position of the semiconductor wafer, and determining defects. A semiconductor chip sorting apparatus comprising a spot illuminator that obliquely irradiates light onto the upper surface of the semiconductor wafer from above the semiconductor wafer.