JP2002313858A - Ic test system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an IC test system by which probers and probe cards are never damaged because of a human error. SOLUTION: The IC test system has a prober B7, a pump B4, a card detaching/attaching switch B1 which outputs suction instruction signals, a pump operating circuit B2 which outputs pump operating signals when the suction instruction signals are outputted, and an interlock circuit B6 which transmits the pump operating signals to the pump B4. In this system, the prober B7 outputs prober in-motion signals or wafer in-measurement signals. The interlock circuit B6 does not transmit the pump operating signals to the pump B4 when prober in-motion signals are outputted but transmits the pump operation signals when the wafer in-measurement signals are outputted. When neither the prober in-motion signals nor the wafer in-measurement signals are outputted from the prober B7, the interlock circuit B6 transmits pump operating signals outputted from the pump operating circuit B2 to the pump B4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an IC test system, and more particularly to a circuit for protecting a prober or the like in an IC test system. More specifically, the present invention relates to a protection circuit for preventing a prober from being damaged when a prober automatically replaces a probe card or when an IC test system performs wafer measurement.

[0002]

2. Description of the Related Art I. Connecting an IC tester and a prober
In the C test system, when exchanging the probe card adsorbed on the test head, the probe card is manually released and exchanged.

FIG. 3 is a flowchart showing the operation of a conventional IC test system. When measuring a wafer with this IC test system, the wafer measurement is started (step S1), and after the wafer measurement is completed (step S2), the probe card is manually released (step S3). Thereafter, in order to measure the next wafer, the prober is operated to automatically replace the probe card (step S4). After the replacement, the probe card is manually sucked (step S5), and the wafer measurement is restarted (step S1).

[0004] Further, when the test head is rotated from a position where the test head and the prober are connected to enable wafer measurement to a position inverted by 180 degrees (a position where the test head operates alone), and vice versa, When rotating the test head from the 180-degree inverted position to a position where wafer measurement can be performed, the operator rotates the test head after confirming that there is no probe card (the probe card is not sucked).

[0005]

However, according to the above-mentioned prior art, the operator manually releases or adsorbs the probe card before and after the automatic probe card exchanging process, or confirms that the probe card is not adsorbed. Since the test head is rotated after the confirmation, human errors may occur. For example, there is a possibility that an error occurs that the automatic replacement is performed while the probe card is being sucked. Further, there is a possibility that an error of rotating the test head while the probe card is being sucked may occur. Then, such a mistake may damage the prober or the probe card.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and provides an IC test system in which a prober or a probe card is not damaged by a human error.

[0007]

According to a first aspect of the present invention, there is provided a prober for holding a probe card, a test head for sucking the probe card, and a negative pressure for sucking the probe card to the test head. A pump to be generated, a card detachment switch for outputting a release instruction signal or a suction instruction signal, and when a suction instruction signal is output from the card detachment switch, a pump operation signal is output and a release instruction is issued from the card detachment switch. When the signal is output, a pump operation circuit that stops outputting the pump operation signal, and an interface that transfers the pump operation signal to the pump on condition that the pump operation signal is output from the pump operation circuit. In an IC test system having a lock circuit, the prober operates when the prober operates. While the prober is operating, the IC test system outputs the wafer measurement signal while the wafer is being measured, and the interlock circuit outputs the prober operation signal from the prober. Regardless of whether or not a pump operation signal is output from the pump operation circuit, the pump operation signal is not sent to the pump, and when a wafer measurement signal is output from the prober, the pump operation circuit is output. A pump operation signal is sent to the pump regardless of whether or not a pump operation signal is output from the prober.If neither a prober operation signal nor a wafer measurement signal is output from the prober, a pump operation signal is output from the pump operation circuit. The pump operation signal is transferred to the pump on condition that is output. It is a C test system.

According to a second aspect of the present invention, there is provided a prober for holding a probe card, a test head for sucking the probe card, and a pump for generating a negative pressure for sucking the probe card to the test head. An IC test system that detects a negative pressure generated by the pump, outputs a release detection signal if the detected negative pressure is greater than a set pressure, and outputs an adsorption detection signal if the detected negative pressure is equal to or less than the set pressure. A pressure sensor to output, when this pressure sensor outputs a release detection signal, sends a prober operation permission signal to the prober, and when the pressure sensor outputs a suction detection signal, outputs a prober operation inhibition signal An IC test system comprising a determination circuit for sending a signal to a prober.

According to a third aspect of the present invention, there is provided a card removal switch for outputting a release instruction signal or a suction instruction signal,
A pump operation circuit that outputs a pump operation signal when the suction instruction signal is output from the card removal switch, and stops the output of the pump operation signal when the release instruction signal is output from the card removal switch. And an interlock circuit that transfers the pump operation signal to the pump on condition that a pump operation signal is output from the pump operation circuit. The determination circuit includes a pump operation signal from the pump operation circuit. The IC test system according to claim 2, wherein the prober operation prohibition signal is sent to the prober on condition that is output.

According to a fourth aspect of the present invention, there is provided a prober for holding a probe card, a test head for sucking the probe card, a pump for generating a negative pressure for sucking the probe card to the test head, and a pump. A pressure sensor that detects a negative pressure generated by the pump, outputs a release detection signal if the detected negative pressure is greater than a set pressure, and outputs a suction detection signal if the detected negative pressure is equal to or less than the set pressure; When the sensor outputs the release detection signal, sends a prober operation permission signal to the prober,
2. The IC test system according to claim 1, further comprising: a determination circuit that sends a prober operation prohibition signal to the prober when the pressure sensor outputs a suction detection signal.

The invention according to claim 5 is characterized in that the determination circuit sends the prober operation inhibition signal to the prober on condition that a pump operation signal is output from the pump operation circuit. An IC test system according to claim 4.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an IC test system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an IC test system according to an embodiment of the present invention. When the operator turns on the card removal switch B1, a suction instruction signal is sent as the signal B11 from the card removal switch B1 to the pump operation circuit B2. Then, the pump operation circuit B2 becomes
The pump operation signal B13 is sent to the judgment circuit B5 and the interlock circuit B6. The interlock circuit B6 transfers the pump operation signal B13 sent from the pump operation circuit B2 to the pump B4. Upon receiving the pump operation signal B13 from the interlock circuit B6, the pump B4 starts a vacuum operation and reduces the air pressure to a set pressure at which the probe card can be sucked. As a result, the prober B7 sucks the probe card.

The pressure sensor B3 monitors the above air pressure. When the air pressure becomes equal to or lower than the set pressure, the pressure sensor B3 sends a suction detection signal as a signal B12 to the determination circuit B5. Upon receiving this suction detection signal and the pump operation signal B13 sent from the pump operation circuit B2, the determination circuit B5 sends a prober operation inhibition signal as a signal B14 to the interlock circuit B6. The interlock circuit B6 includes a determination circuit B
5 is transferred to the prober B7. Accordingly, the interlock circuit B6 is
The prober operation prohibition signal sent from the prober B7
Transfer to The prober operation inhibition signal is
7 prohibits the operation of automatically replacing the probe card and the operation of rotating the test head.

The operator operates the card removal switch B1.
Is turned off, a release instruction signal is sent as a signal B11 from the card removal switch B1 to the pump operation circuit B2. Then, the pump operation circuit B2 outputs the pump operation signal B
Stop outputting 13. Accordingly, the interlock circuit B6 also outputs the pump operation signal B13 to the pump B4.
Stop forwarding to. When the pump operation signal B13 is no longer transferred from the interlock circuit B6, the pump B4 terminates the vacuum operation, and makes the air pressure higher than the set pressure at which the probe card can be sucked. This allows
Prober B7 releases the probe card.

The pressure switch B3 monitors the above air pressure, and when the air pressure becomes higher than the set pressure, sends a release detection signal as a signal B12 to the judgment circuit B5. Upon receiving this release detection signal, the determination circuit B5 sends a prober operation permission signal as a signal B14 to the interlock circuit B6. The interlock circuit B6 includes a determination circuit B5
Is transmitted to the prober B7.
Therefore, the interlock circuit B6 transfers the prober operation permission signal sent from the determination circuit B5 to the prober B7. The prober operation permission signal is output from the prober B7.
However, the operation of automatically changing the probe card and the operation of rotating the test head are permitted. As a result, the prober B7 can automatically change the probe card,
It is possible to start the operation of rotating the test head.

The prober B7 keeps sending a signal indicating that the prober is operating as a signal B15 to the interlock circuit B6 during the operation of automatically changing the probe card and the operation of rotating the test head. The interlock circuit B6 is connected to the pump B while the prober operating signal is being received from the prober B7 regardless of whether the pump operating signal B13 is sent from the pump operating circuit B2.
4 does not send the pump operation signal B13.

Thus, while the prober B7 is performing the operation of automatically changing the probe card or the operation of rotating the test head, the operator erroneously turns on the card removal switch B1 (instructs suction). Also, the probe card is not sucked. Therefore, the prober B7 and the probe card are not damaged.

While the IC tester B8 is measuring the wafer, the prober B7 continues to send the wafer in-measurement signal as the signal B15 to the interlock circuit B6. The interlock circuit B6, while receiving the wafer measurement signal from the prober B7, regardless of whether or not the pump operation signal B13 is sent from the pump operation circuit B2.
A pump operation signal B13 is sent to the pump B4.

As a result, even if the operator mistakenly turns off (instructs release) the card removal switch B1 while the IC tester B8 measures the wafer, the probe card during wafer measurement is released. There is no.
Therefore, the probe card does not come off due to a human error during wafer measurement.

FIG. 2 is a flowchart showing the operation of the IC test system according to this embodiment. When the operator turns off (release instruction) the card removal switch B1 (A0), the operation of the pump B4 is stopped. And
When the air pressure becomes higher than the set pressure, the pressure sensor B3
A release detection signal is sent to the determination circuit B5 (A1). The determination circuit B5 determines whether the probe card is attracted or released based on whether or not the release detection signal has been sent from the pressure switch B3 (A3).

If the probe card is adsorbed (YE
S), the determination circuit B5 sends a prober operation prohibition signal to the interlock circuit B6 (A2), and returns to step A0. The interlock circuit B6 transfers the prober operation inhibition signal sent from the determination circuit B5 to the prober B7. Therefore, if the probe card is sucked, the operation of automatically changing the probe card and the operation of rotating the test head by the prober B7 are prohibited, and the damage of the prober B7 and the probe card can be prevented.

If the probe card is released (N
O), the determination circuit B5 sends a prober operation permission signal to the interlock circuit B6 (A4). The interlock circuit B6 transfers the prober operation permission signal sent from the determination circuit B5 to the prober B7. Then, the prober B7 starts an operation of automatically replacing the probe card and an operation of rotating the test head, and at the same time, continuously sends a signal indicating that the prober is operating to the interlock circuit B6 during the operation (A5).

The interlock circuit B6 operates even when the card removal switch B1 is turned on (instruction to suck).
To keep the probe card released,
While the prober operating signal is being received from the interlock circuit B6, the pump operating signal B13 is not sent to the pump B4 regardless of whether or not the pump operating signal B13 is sent from the pump operating circuit B2 (A6). That is,
While the prober B7 is operating, the probe card is not sucked. After terminating the operation of the prober B7, the prober B7 stops transmitting the signal indicating that the prober is operating to the interlock circuit B6 (A7).

Next, when the operator turns on (instructs suction) the card removal switch B1 for wafer measurement (A8), the operation of the pump B4 is started. And
When the air pressure falls below the set pressure, the pressure sensor B3 sends a suction detection signal to the determination circuit B5 (A9). Judgment circuit B
5 determines whether the probe card is being sucked or released based on whether or not a suction detection signal is sent from the pressure sensor B3 (A10).

If the probe card is released (N
O), the determination circuit B5 sends a prober operation permission signal to the interlock circuit B6 (A11), and returns to step A8. The interlock circuit B6 transfers the prober operation permission signal sent from the determination circuit B5 to the prober B7.

If the probe card is adsorbed (YE
S), the determination circuit B5 sends a prober operation prohibition signal to the interlock circuit B6 (A12). The interlock circuit B6 transfers the prober operation inhibition signal sent from the determination circuit B5 to the prober B7. Then, the IC tester B8 starts measuring the wafer, and during the wafer measurement, the prober B7 keeps sending a signal indicating that the wafer is being measured to the interlock circuit B6 (A13).

The interlock circuit B6 operates even when the card removal switch B1 is turned off (release instruction).
In order to keep the state where the probe card is sucked,
While the wafer measurement signal is being received from the prober B7, the pump operation signal B13 is output from the pump operation circuit B2.
The pump operation signal B13 is sent to the pump B4 regardless of whether or not is sent (A14). That is, the probe card is not released during wafer measurement. When the IC tester B8 completes the wafer measurement,
The prober B7 stops sending a signal during wafer measurement to the interlock circuit B6 (A15).

As described above, one embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to the above-described embodiment, and departs from the gist of the present invention. The present invention includes design changes in a range not to be performed.

[0029]

As described above, according to the IC test system of the present invention, while the prober is performing the operation of automatically changing the probe card and the operation of rotating the test head, the operator can perform the operation. Even if the card removal switch is accidentally turned on (adsorption instruction), the probe card will not be adsorbed. Therefore, the prober and the probe card are not damaged.

Further, even if the operator mistakenly turns off the card removal switch (release instruction) while the IC test system is measuring the wafer, the probe card during wafer measurement will not be released. . Therefore,
The probe card does not come off due to human error during wafer measurement.

Further, according to the present invention, the operation of the prober is prohibited while the probe card is being sucked, so that the prober and the probe card are not damaged.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an IC test system according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the IC test system according to the embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of a conventional IC test system.

[Explanation of symbols]

 B1 Card removal switch B2 Pump operation circuit B3 Pressure sensor B4 Pump B5 Judgment circuit B6 Interlock circuit B7 Prober B8 IC tester B11, B12, B14, B15 signal B13 Pump operation signal

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G003 AA10 AG04 AG05 AH01 AH04 AH07 2G132 AA00 AE03 AF00 AF01 AL31 AL35 4M106 AA01 BA01 CA70 DD10 DD23 DD30

Claims (5)

[Claims] A prober for holding a probe card; a test head for sucking the probe card; a pump for generating a negative pressure for sucking the probe card to the test head; and a release instruction signal or a suction instruction signal. A card detachment switch to be output, a pump operation signal is output when the suction instruction signal is output from the card removal switch, and a pump operation signal is output when the release instruction signal is output from the card removal switch. An IC test system comprising: a pump operation circuit that stops output; and an interlock circuit that transfers the pump operation signal to the pump on condition that a pump operation signal is output from the pump operation circuit. While the prober is operating, the prober operating signal is output. And outputting an in-wafer measurement signal while the IC test system is measuring the wafer. The interlock circuit is configured to output a signal indicating that the prober is operating from the prober when the prober is operating. Regardless of whether or not a signal has been output, the pump operation signal is not sent to the pump, and if a signal during wafer measurement is output from the prober, whether or not a pump operation signal has been output from the pump operation circuit Regardless, a pump operation signal is sent to the pump, and when neither the prober operation signal nor the wafer measurement signal is output from the prober, the pump operation signal is output from the pump operation circuit. An IC test system for transferring a pump operation signal to the pump. 2. An IC test system comprising: a prober for holding a probe card; a test head for sucking the probe card; and a pump for generating a negative pressure for sucking the probe card to the test head. A pressure sensor that detects a negative pressure generated by the pump, outputs a release detection signal if the detected negative pressure is greater than a set pressure, and outputs an adsorption detection signal if the detected negative pressure is equal to or less than the set pressure; A determination circuit that sends a prober operation permission signal to the prober when the pressure sensor outputs the release detection signal, and sends a prober operation inhibition signal to the prober when the pressure sensor outputs a suction detection signal. An IC test system comprising: 3. A card detachment switch for outputting a release instruction signal or a suction instruction signal, and when a suction instruction signal is output from the card detachment switch, a pump operation signal is output, and a release instruction is issued from the card detachment switch. A pump operation circuit for stopping the output of the pump operation signal when the signal is output; and an interface for transferring the pump operation signal to the pump on condition that the pump operation signal is output from the pump operation circuit. 3. The locker circuit, wherein the determination circuit sends the prober operation inhibition signal to the prober on condition that a pump operation signal is output from the pump operation circuit. IC test system. A prober for holding the probe card; a test head for sucking the probe card; a pump for generating a negative pressure for sucking the probe card to the test head; and a negative pressure generated by the pump. A pressure sensor that detects and outputs a release detection signal if the detected negative pressure is greater than the set pressure, and outputs a suction detection signal if the detected negative pressure is equal to or less than the set pressure, and the pressure sensor outputs a release detection signal A determination circuit for sending a prober operation permission signal to the prober when the pressure sensor outputs a suction detection signal, and a prober operation inhibition signal to the prober when the pressure sensor outputs a suction detection signal. 2. The IC test system according to 1. 5. The IC according to claim 4, wherein the determination circuit sends the prober operation inhibition signal to the prober on condition that a pump operation signal is output from the pump operation circuit. Test system.