JPS6037715A - Defective dice detector - Google Patents

Abstract

PURPOSE:To notice defective dice surely and easily by constituting a detector with a color sensor for converting the color of dice surface into an electrical signal, means for storing the electrical signal value corresponding to the surface color of non-defective dice, and means for effecting comparative operation to determine whether the dice are defective or not, and by marking defective dice with a different color ink. CONSTITUTION:A diced semiconductior wafer 1 is bonded onto a X-Y table 7. A plurality of dice produced by dicing are tested with respect to their electrical properties to determine defective dice, on which applied is ink having a color clearly different from the reflection color produced depending on the condition of the dice surface. Then each dice is scanned, uniting the optical axis B of a television camera 6 and a television lens 5 with the optical axis A of a color sensor head 4 and a color sensor lens 3 on the subject dice. The detected color is compared by a comparator 9 with the color of a non-defective dice surface stored in a memory 8. If the dice is determined as defective it is not picked up.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention provides a TC (Integrated C1rcui)
t) In the assembly process, defective dies used in a die picking device that automatically separates good dies from defective dies and gives a big amplification only to the good dies (background technology) In the conventional die picking device, defective dies are As a means for detecting defects, a video unit installed on the top of the die that recognizes the position of the die is used, the pattern on the die surface is binarized, the binarized information is stored in memory, and the defective die is detected. There is a method that performs arithmetic processing on the shape, area, etc. of the defective mark placed on the product to determine whether it is acceptable or defective. The die picking device picks up only good dice based on this determination result.

However, in such conventional detection devices,
Depending on the IC pattern and the position of the defective mark, it may not be possible to detect the defective mark, so there is a problem that it is impossible to determine whether the die is good or bad.Furthermore, since the defective mark is processed by calculation, it can be determined whether the die is good or bad. There was a problem that the judgment speed was slow.

(Object of the invention) The present invention solves such conventional problems,
A color sensor that converts the power source of the 6C+J-Lk juice into an electrical signal, and a storage means that stores and retains the value of the electrical signal corresponding to the surface color of the surface of the good die. and determining means for comparing and calculating the stored electrical signal and the electrical signal obtained from the color sensor to determine whether the die is a good product or a defective product. This defective die detection device includes a defective mark marked with ink of a color different from the surface color of the die.

Hereinafter, the present invention will be explained based on the drawings.

(Structure and operation of the invention) One feature of the present invention is that the color of the ink of the defective mark attached to the defective die is used as a criterion for determining whether the die is good or defective. As the defect mark σ) color, select a color that is clearly different from the reflected color caused by the surface condition of the die. For example, it is preferable to use a complementary color or a color close to a complementary color to the reflected color, or a) a primary color or a color close to a primary color.

An embodiment of the present invention is shown in the drawings. In the figure, ``■'' is a diced wafer fixed to the XY table 7. Reference numeral 2 indicates the above-mentioned defective mark, 3 indicates a color sensor lens, and 4 indicates a color sensor head, which constitute a color sensor. Various other color sensors can be used, such as those using light receiving diodes, those using color television cameras, and interferometers using diffraction gratings. 5 is a television lens, and 6 is a television camera. The optical axis A of the color sensor lens 3, the optical axis 13 of the television lens 5, and their fields of view are adjusted so that the same image is viewed. A memory 8 stores and holds an electric signal corresponding to the surface color of the non-defective die surface. Reference numeral 9 denotes a comparator, in which the memory 8 uses the output signal as a reference to perform comparison calculations with the signals detected by the color sensor lens 3 and the color sensor head 5, and outputs a defect signal when a defective mark is detected. Next, the operation will be explained.

First, drive the XY table 7 and move the dice to the TV camera 6.
put it in perspective. Since the optical axis A of the color sensor lens 3 is adjusted as described above, the color sensor head 4
Six identical die surfaces are also in the field of view of the television camera.

At this time, if there is a defect mark 2 on the die surface, the color saturation is detected by the color sensor head 4, and an electric signal corresponding to the detected saturation is output to the comparator 9. The comparator 9 compares this signal with an electrical signal corresponding to the surface color of a good die stored in the memory 8 to obtain a value n. When a defective mark is detected, a defective signal is output because the difference in saturation between these marks is less than or equal to a predetermined value.

When a defective signal is detected in this manner, the die picking device does not pick up the defective dice.

(Effects of the Invention) As explained above, according to the present invention, since color is used as a criterion for determining whether a die is good or bad, it is possible to easily detect defects that were previously difficult to detect depending on the position of the JC pattern and defective mark. configuration, it can be reliably detected. Furthermore, it is possible to obtain the effect that the speed of determining whether the video section is good or bad is faster than in the conventional case.

[Brief explanation of drawings]

The figure is a configuration diagram and does not show one embodiment of the present invention. 1... Dice, 2... Defective mark 3... Color seven-piece lens r/J... Color sensor head 5... TV camera lens, 6... TV camera 7... XY table, 8... Memory 9... Comparator Patent applicant Oki Electric Industry Co., Ltd. Patent application agent Megumi Yamamoto -

Claims (1)

[Claims] A color sensor that converts the surface color of the dice into an electrical signal,
A memory means for storing and storing the value of an electric signal corresponding to the surface color of the surface of the finished die, and a comparison operation is made between the stored electric signal and the electric signal obtained from the color sensor to determine whether the die is good or defective. A device for detecting a defective die, comprising a determination means for determining whether the die is a good die, and a defective die is coated with ink of a color different from the surface color of the non-defective die as a defective mark in advance on the defective die. .