JPS6311777B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a method for testing and classifying semiconductor chips.

Because packaging costs are high for semiconductor devices, semiconductor chips (hereinafter simply referred to as chips) are tested before packaging. Also, there are cases where only the chips are sold, and even in this case, testing of the chips is required. Usually the chip test is
A large number of chips are arranged on a tray and tested one after another. If the chip is, for example, a diode (including a Zener diode) chip, the lower measuring needle is raised from below the tray to push up the chip, and the upper measuring needle is lowered from above to clamp the chip. Perform the required characteristic tests. After testing, the chips are returned to the surface of the tray.

By the way, once the above-mentioned tests are completed, the chips are then classified according to their characteristics based on the test results. Conventionally, for this classification, the chips are picked up again from the tray by a handling device, a classification case that matches the characteristics of the chips is selected from among multiple classification cases prepared separately, and the chips are stored in that case. . Therefore, it is necessary to prepare a measuring needle for chip testing and a handling device for classification, which makes the configuration complicated and the time required for one cycle from measurement to classification. It had the drawback of being inevitably long.

The object of the present invention is to perform the operations from chip testing to sorting continuously, thereby shortening the cycle time required for this, and simplifying the configuration for this purpose.

Embodiments of the invention will be described with reference to the drawings. Reference numeral 1 designates a tray for chips, on the surface of which is stretched a sheet on which a large number of chips 2 are adhered. This arrangement can be done as follows. That is, a wafer is attached to adhesive expanding tape, and then this wafer is scribed. After completing the scribe, extend the expanded tape outward from the periphery. Then, it is stretched out and pasted on the tray. Then, the chips are separated from each other with a gap between them. As a result, each chip is arranged in parallel vertically and horizontally.

Tray 1 is sequentially moved using an XY table or the like to guide each chip to its removal position.

Reference numeral 3 denotes a lower measuring needle, which is held in a fixed position by a holder 4 and moves up and down as the holder 4 moves up and down. This elevating mechanism 5 is optional, but in the illustrated example, an arm 7 that swings about a shaft 6 is provided, and the tip of the arm 7 comes into contact with a roller bearing 8 at the lower end of the holder 4. As the arm 7 swings, the holder 4 moves up and down. 9 is a bearing for sliding the holder 4. When the holder 4 rises, the lower measuring needle 3 breaks through the expandable tape and pushes the tip 2 up.

Reference numeral 10 denotes an upper measuring needle which is held by a holder 11. The holder 11 is movable vertically and horizontally. In accordance with the invention, the upper measuring needle 10 has a central through hole 12, as shown enlarged in FIG.
It is constructed into a hollow body with The inside thereof is connected to a vacuum pump 14 via a pipe 13. Therefore, a suction force is applied to the tip 10a of the upper measuring needle 10 by the action of the vacuum pump 14.

Next, the measurement operation will be explained first. The upper measuring needle 10 is lowered from above one chip 2 to be measured and brought into contact with its surface. This contact exerts a suction force on the tip 2, but the adhesiveness of the expanding tape prevents the tip from separating from the tape. In this state, the lower measuring needle 3 is raised to push up the tip 2. As a result, the tip 2 separates from the expanding tape for the first time, and at the same time the upper measuring needle 10 also rises, thus causing the tip 2 to move away from the expanding tape.
is held between the upper and lower measuring needles 3 and 10 and floats in the air. In this state, a voltage is applied between both measuring needles 3 and 10 to perform the required test. If the chip 2 is, for example, a diode chip, it goes without saying that the diode characteristics can be measured by applying a voltage with each measuring needle in contact with its anode and cathode.

As mentioned above, when the above-mentioned measurement was completed, conventionally both measuring needles were lowered to return the tip to its original position, and a separately prepared handling device was used to grasp the tip again. . However, in this invention, after the measurement is completed, only the lower measuring needle 3 is lowered to the initial position. This lowering causes the lower measuring needle 3 to separate from the tip 2, but since the tip 2 is attracted by the upper measuring needle 10, it does not fall. Under this condition, the holder 11 moves horizontally.

On the other hand, cases 16 for each classification are placed on a classification table 15 separately. Then, the chip 2 carried by the upper measuring needle 10 based on the movement of the holder 11 reaches the upper part of the classification case 16 determined according to the result of the previous measurement. In the figure, 10' and 11' are the upper measuring needles located at this upper position.
Shows holder. Then, the suction force by the vacuum pump is released and the chips 2 are stored in the classified case 16. After this, the holder 11 moves again towards its original position and stops above the next chip. Meanwhile, the next tip has been moved above the lower measuring needle 3. Then, the test is carried out again using both measuring needles 3 and 10. Repeat this below.

As described in detail above, according to the present invention, after the test measurement, the upper measuring needle is moved to the upper part of the classification case together with the chip attached to it, so the time required from the test to the classification is can be shortened compared to the conventional one, and since the upper measuring needle is also used as a handling mechanism, the structure can be simplified compared to a device equipped with a dedicated handling mechanism.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram for explaining an embodiment of the present invention, and FIG. 2 is a partially enlarged sectional view. 1...Tray, 2...Semiconductor chip, 3...Lower measuring needle, 10...Upper measuring needle, 16...Case by classification.

Claims (1)

[Claims] 1. A sheet with a plurality of semiconductor chips adhered to its upper surface is stretched over a tray, the tray is sequentially moved to guide each semiconductor chip to a take-out position, and at the take-out position, the sheet is placed above the tray, up and down, and an upper measuring needle disposed horizontally movably and equipped with a suction port for vacuum suction at its tip; and a lower measuring needle disposed movably up and down on the back side of the tray at the take-out position; The semiconductor chips are separated from the sheet at a position above the top surface of the tray by moving them close to each other, and are held between the lower measuring needle and the upper measuring needle while being vacuum suctioned by the suction port of the upper measuring needle. Electricity is applied between the measuring needle and the lower measuring needle to test the characteristics of the semiconductor chip, and then the lower measuring needle is lowered, and the upper measuring needle is moved to the previous position with the semiconductor chip vacuum-adsorbed. The semiconductor chip is moved to the upper part of the classified case corresponding to the test result, the vacuum suction is released, and the semiconductor chip is stored inside the classified case. After the semiconductor chip is stored, the upper measuring needle is moved to the top of the tray. A method for testing and classifying semiconductor chips in which the chips are returned to the upper removal position.