KR100834176B1 - Charge eliminating apparatus and method, and program storage medium - Google Patents

Abstract

When the mounting table on which the subject is mounted and the probe card are relatively moved, and the subject under test and the probe card are in electrical contact with each other to perform the electrical characteristics and inspection of the subject under test, the examination is carried out through the mount. An antistatic device for removing static electricity from a body is provided. The antistatic device includes a grounding wire for grounding the mounting table, a relay switch provided in the grounding wire, and a switch controller for opening and closing the relay switch.

Inspected object, antistatic device, antistatic method, program recording medium

Description

Antistatic device, antistatic method and program recording medium {CHARGE ELIMINATING APPARATUS AND METHOD, AND PROGRAM STORAGE MEDIUM}

The present invention relates to an antistatic device, an antistatic method and a program recording medium, and more particularly, an antistatic device, an antistatic method and an antistatic method capable of eliminating the influence of static electricity charged on an inspected object when performing the electrical property inspection of the inspected object. A program recording medium for storing a program for performing the above.

In the post-process of semiconductor manufacturing, there exists a process of inspecting the to-be-tested object (for example, wafer) in which the some device was formed using the inspection apparatus as it is. This inspection apparatus is provided with the loader chamber for conveying the wafers accommodated in the cassette one by one, and the prober chamber for performing the electrical characteristic inspection of the wafer received from this loader chamber.

The loader chamber includes a wafer transfer mechanism for transferring wafers one by one, and a prealignment mechanism for aligning the direction of the wafer on the basis of the orientation flat <orientation plate> or notch of the wafer while transferring the wafer via the wafer transfer mechanism (hereinafter, " Sub-chuck ". On the other hand, the probe chamber is mounted on the wafer and moved in the X, Y, and Z directions, and at the same time rotates forward and backward in the θ direction (hereinafter referred to as a “main chuck”), a probe card disposed above the main chuck; And an alignment mechanism for performing alignment of the probe of the probe card and the wafer on the main chuck. Further, a test head for electrically contacting the probe card is disposed on the head plate of the prober chamber, and a predetermined signal is transmitted and received between the tester and the probe card through the test head.

In the case of inspecting the wafer, in the loader chamber, the wafer conveyance mechanism conveys the wafer in the cassette, performs prealignment via the subchuck, and then the wafer conveyance mechanism mounts the wafer on the main chuck in the prober chamber. In the prober chamber, while the main chuck moves in the X, Y, Z and θ directions, the wafer and the probe of the probe card are aligned via the alignment mechanism. After that, the main chuck moves in the X and Y directions, and the first device on the wafer is positioned just below the probe, and then the main chuck is raised in the Z direction to electrically contact the device and the probe to perform inspection of the device. do. After the inspection, the main chuck descends, the main chuck performs index feeding of the wafer, and performs inspection of other devices sequentially. After the inspection of the last device on the wafer, the wafer is returned to its original position in the cassette via the main chuck and the wafer transfer mechanism, and the inspection of the remaining wafers is sequentially performed.

By the way, static electricity is charged to the main chuck and the wafer by friction with air or the like during the movement of the main chuck while the inspection is being executed. This phenomenon is difficult to avoid, and if left as it is, the wiring structure of the device may be damaged during the inspection due to the influence of static electricity. In particular, this phenomenon is remarkable due to the fine structure of the device. Therefore, the present applicant has proposed the static elimination mechanism of the main chuck in Patent Document 1. In this static elimination mechanism, the static electricity of the main chuck is removed while the wafer is transferred between the wafer transfer mechanism and the main chuck.

(Patent Document 1) Japanese Patent Laid-Open No. 2003-218175

However, since the static elimination mechanism of Patent Literature 1 cannot remove static electricity from the main chuck during the inspection of the wafer from the start of the inspection of one wafer to the completion of the inspection, the static electricity is removed from the main chuck during the inspection of one wafer. Gradually accumulates, and a difference occurs in the inspection result between devices as the inspection progresses, which may lower the reliability of the inspection. In particular, when the wiring structure of the device is after the 65 nm process as in recent years, since the applied current during inspection is extremely small, the influence of the static electricity on the wafer becomes remarkable, the influence on the inspection result becomes large, and the reliability decreases, and the extreme In some cases, the wiring structure of the device may even be damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and eliminates the influence of static electricity, and can improve the reliability of inspection of the inspected object and at the same time reliably prevent the damage of the inspected object even in an ultrafine structured test object after the 65 nm process. An object of the present invention is to provide an antistatic device, an antistatic method, and a program recording medium storing a program for performing the antistatic method.

In the antistatic device according to claim 1 of the present invention, the mounting table on which the test target is mounted and the probe card are relatively moved, and the test target object and the probe card of the mounting target are in electrical contact with each other to test the electrical characteristics of the test target. An antistatic device for removing static electricity charged to the object under test via the mounting table when executed, the grounding wiring for grounding the mounting table, the relay switch provided in the grounding wiring, and the opening and closing control of the relay switch. It is characterized by having a switch controller.

In addition, in the invention according to claim 1, the antistatic device according to claim 2 of the present invention has the top plate having a top plate serving as a mounting surface of the inspected object, and the grounding wire is a first formed on the top surface of the top plate. It is connected to a conductor film, It is characterized by the above-mentioned.

The antistatic device according to claim 3 of the present invention is the invention according to claim 2, wherein the mounting table is connected to a test head through a cable, and the grounding wire is electrically connected to a center conductor of the cable. It is to be done.

In the antistatic device according to claim 4 of the present invention, in the invention according to claim 3, the outer conductor of the cable is electrically connected to a second conductor film formed on the lower surface of the top plate.

Moreover, the antistatic device of Claim 5 of this invention is an invention of Claim 4 WHEREIN: The outer conductor of the said cable is connected to the storage case of the said relay switch via wiring.

The antistatic device according to claim 6 of the present invention is the invention according to any one of claims 1 to 5, wherein the relay switch is configured to be manually operated.

Moreover, the antistatic device of Claim 7 of this invention was equipped with the charge confirmation apparatus which checks the charging state of the said test subject in the invention of Claim 1, It is characterized by the above-mentioned.

The antistatic device according to claim 8 of the present invention is the invention according to claim 7, wherein the charge confirmation device has a means for setting an allowable range of charging potential.

The antistatic device according to claim 9 of the present invention is the invention according to claim 8, characterized in that the charge confirmation device has a means for determining that it is out of an allowable range of the charge potential.

The antistatic device according to claim 10 of the present invention is the invention according to claim 8 or 9, wherein the charge confirmation device has a means for displaying the charge potential.

In addition, according to the antistatic method according to claim 11 of the present invention, the mounting table on which the test target is mounted and the probe card move relatively, and the test target mounted on the mounting target and the probe card are in electrical contact with each other. A method of eliminating static electricity charged to the inspected object by using a relay switch provided on the grounding wiring of the mounting table when conducting an electrical characteristic test, wherein the relay is not in electrical contact with the inspected object. The first step of removing the static electricity of the test object by grounding the mount by closing the switch, and grounding the mount by opening the relay switch when the test object and the probe card are in electrical contact with each other. It is characterized by including the second step of releasing .

The antistatic method according to claim 12 of the present invention is the invention according to claim 7, wherein the first step is a step in which the probe card and the mounting table move relatively.

In the antistatic method according to claim 13 of the present invention, in the invention according to claim 7, the first step includes a step of mounting the inspected object on the mounting target, and a process of aligning the inspected object with the probe card. It characterized in that it comprises a.

The antistatic method according to claim 14 of the present invention is the invention according to claim 7, wherein the first step includes a step of removing the test object from the mounting target.

The antistatic method according to claim 15 of the present invention is the invention according to claim 7, wherein the second step includes a step in which the mounting table overdrives the inspected object.

Moreover, the antistatic method of Claim 16 of this invention was equipped with the 3rd process which checks whether the said to-be-tested object is charged or uncharged in any one of Claims 11-15 characterized by the above-mentioned. It is.

In the antistatic method according to claim 17 of the present invention, in the invention according to claim 16, the step of confirming the charging is a step after the alignment step.

The program recording medium according to claim 18 of the present invention is a computer driven device that relatively moves a mounting table on which a test target is mounted and a probe card, and electrically contacts the test target object to be mounted with the probe card. A recording medium having recorded thereon a program for executing a method of removing static electricity of the inspected object through the mount by using a relay switch provided in the grounding wiring of the mount when performing the electrical characteristic inspection of the inspected object, A first step of grounding the mounting table to remove static electricity of the inspected object by closing the relay switch when the inspected object and the probe card are not in electrical contact, and the inspected object and the probe card Opening the relay switch when in electrical contact By a second step of releasing the ground of the mounting table.

The program recording medium according to claim 19 of the present invention is the invention according to claim 18, characterized in that a third step of confirming the charging state of the test subject is performed.

According to the present invention, there is provided a static elimination device and a static elimination method capable of eliminating the influence of static electricity and improving the reliability of inspection of the inspected object and at the same time reliably preventing the inspection of the inspected object even after the ultrafine structure after the 65 nm process; A program recording medium storing a program for performing the antistatic method can be provided.

Hereinafter, this invention is demonstrated based on embodiment shown to FIGS. 1-6C.

The inspection apparatus 10 provided with the antistatic device of this embodiment is equipped with the loader chamber 11 and the prober chamber 12, for example, as shown in FIG. 1, and controls a control apparatus (not shown). Is configured to carry out an electrical property inspection of the wafer W under the following conditions.

As shown in FIG. 1, the loader chamber 11 includes an accommodating part (not shown) for accommodating a plurality of wafers W, a wafer conveyance mechanism (not shown) for carrying in and out of the wafer W, and a wafer W. A sub chuck (not shown) for performing prealignment is provided. In the loader chamber 11, the wafer transfer mechanism is pre-aligned in the sub-chuck while the wafer W is transported, and then the wafer W is passed between the probe chamber 12.

As shown in FIG. 1, the probe chamber 12 mounts the wafer W and moves in a horizontal direction and a vertical direction (hereinafter referred to as a “main chuck”) 14 and the main chuck 14. A probe card 15 disposed above and an alignment mechanism (not shown) for aligning the plurality of probes 15A of the probe card 15 and the wafer W on the main chuck 14 are provided. In the probe chamber 12, the wafer W on the main chuck 14 and the plurality of probes 15A of the probe card 15 are aligned by the alignment mechanism, and then the plurality of probes 15A and the wafer W are electrically connected. The wafer W to be inspected for electrical characteristics. When performing the electrical property inspection of the wafer W, a predetermined signal is transmitted and received between the tester (not shown) and the probe card 15 via a test head T disposed on the upper surface of the probe card 15. In addition, the probe card 15 is fixed to the opening of the head plate 16.

As shown in FIG. 1, the main chuck 14 includes, for example, a top plate 14A capable of vacuum-absorbing the wafer W, and an elevating mechanism 14B for elevating the top plate 14A. The top plate 14A is moved up and down via the elevating mechanism 14B while moving in the horizontal direction via the table 17. As shown in FIG. 2, the top plate 14A is formed of an insulating substrate such as ceramic, for example, and the first conductor film 14C is formed on the upper surface thereof, and the lower plate 14A is formed on the lower surface thereof. 2 conductor film 14D is formed. The first and second conductor films 14C and 14D are formed of, for example, thin films of gold.

As shown in FIG. 1, the test head T is electrically connected to the top plate 14A via a cable 18 used for measurement. For example, as shown in FIG. 3, the cable 18 includes a center conductor 18A serving as a transmission path for the measured voltage and the measured current, and a first external conductor covering the center conductor 18A through an insulating material (eg, For example, it has a first shield conductor 18B and a second external conductor (for example, a mesh second shield conductor) 18C covering the first shield conductor 18B through an insulating material, and having a first connector. It is electrically connected to the test head T via 19A, and is electrically connected to the top plate 14A side via the second connector 19B.

As shown in FIGS. 1-3, the center conductor 18A of the cable 18 is electrically connected with the 1st conductor film 14C of the top plate 14A, and the 1st shield conductor 18B is a top. It is electrically connected to the 2nd conductor film 14D of the plate 14A. In addition, the second shield conductor 18C of the cable 18 is grounded as shown in FIG. 3. Accordingly, the test head T transmits an inspection signal to the wafer W via the probe card 15 when the probe card 15 is in electrical contact with the wafer W, and at the same time, the first conductor film on the upper surface of the top plate 14A ( 14C) is also configured to transmit an inspection signal via the center conductor 18A of the cable 18, and to perform an electrical characteristic inspection of the wafer W.

Since the static electricity is charged to many devices formed on the wafer W when the wafer W is inspected, the static electricity may adversely affect the inspection of individual devices. Therefore, in this embodiment, the antistatic device 20 shown in FIGS. 1 and 3 is provided to remove the static electricity charged on the wafer W. As shown in FIG. Thus, an embodiment of the antistatic method of the present invention using the antistatic device 20 and the antistatic device 20 will be described. The program for implementing the antistatic method of the present invention is stored in a storage unit of a computer which is a control device and is executed by driving the computer.

As shown in FIG. 1, FIG. 3, the antistatic device 20 of this embodiment has the grounding wire 22 connected to the center conductor 18A and the earth 21 of the cable 18, respectively, and a ground. Supporting the relay switch 23 provided in the middle of the wiring 22, the ground resistor 24 provided between the earth 21 and the relay switch 23, and the relay switch 23 and the ground resistor 24. The support substrate 25, the switch controller 26 which opens and closes the relay switch 23, and the housing 27 which accommodates components other than the switch controller 26 are provided, and the inspection of the wafer W is performed. At this time, the relay switch 23 is regularly opened and closed under the control of the switch controller 26 to remove the static electricity charged on the top plate 14. This antistatic device 20 is attached to the head plate 16 via the housing 27 as shown in FIG.

As shown in FIG. 3, the relay switch 23 has a coil 23A, a switch 23B arranged in parallel with an axis in the coil 23A, and a case 23C for accommodating the coil 23A. It operates based on the signal from the switch controller 26. The coil 23A is electrically connected to the controller cable 28 via the wiring 23D. The controller cable 28 is electrically connected to the switch controller 26 via the I / O port 28A. In addition, one end of the switch 23B is electrically connected to the grounding wiring 22, and when the electromotive force is applied to the coil 23A based on a signal from the switch controller 26, the center conductor of the cable 18 ( 18A and the earth 21 are electrically connected, and when the electromotive force is lost to the coil 23A, the connection between the center conductor 18A and the earth 21 is released. Since the first shield conductor 18B of the cable 18 extends to the vicinity of the switch 23B via the wiring 22A and is electrically connected to the case 23C, the switch 23B and the case 23C are provided. By setting substantially equal to the equipotential, leakage current and electrical noise from the grounding wiring 22 and the switch 23B can be suppressed. In addition, since the first shield conductor 18B of the cable 18 is electrically connected to the second conductor film 14D on the bottom surface of the top plate 14A, the first conductor film 14D is also used for the second conductor film 14D. Approximately the same voltage as 14C) can be applied. Thereby, the leak current from 14 C of 1st conductor films can be suppressed, and the measurement precision of a device can be improved.

The switch controller 26 may be implemented as a program that is part of a control device made of a computer. The switch controller 26 is stored in the control apparatus via a recording medium on which a program for executing the antistatic method of the present invention is recorded.

In addition, a button switch 29 is mounted to the housing 27 of the static eliminator 20, and the operator applies the force to the relay switch 23 by pressing the button switch 29 to discharge the static electricity. To make it possible. This button switch 29 is electrically connected to the wiring 23D of the coil 23A via the diode 29A as shown in FIG. The button switch 29 is not used when performing the inspection of the wafer W, but used for maintenance, for example. Moreover, this antistatic device 20 is equipped with the charging confirmation device 30 for confirming the charging state of the wafer W as shown to FIG. 4, FIG. The charging check device 30 is used to check the state of charge of the wafer W and to prevent the adverse influence of the static electricity on the wafer W by inspection.

Next, the game check apparatus 30 is demonstrated. As shown in FIG. 4, the game check apparatus 30 includes a surface potential sensor 31 attached to the alignment bridge 40 constituting the alignment mechanism, and a controller 32 connected to the surface potential sensor 31. The surface potential sensor 31 is configured to detect the surface potential of the wafer W. The surface potential sensor 31 is disposed apart from the measurement target surface M of the wafer W by a predetermined distance (for example, several mm), and is configured to detect the surface potential of the measurement target surface M. FIG. When using this charging check device 30, it is necessary to set the threshold value of the surface potential with respect to the controller 32 beforehand, and to perform zero adjust adjustment.

As shown in FIG. 5, the surface potential sensor 31 has a sensor portion 31A and an A / D converter 31B. The surface potential sensor 31 measures the surface potential of the wafer W by the sensor portion 31A, and measures the measured signal. The controller 32 transmits the data to the controller 32 via the A / D converter 31B. As shown in FIG. 5, the controller 32 includes an input, a correction processor 32A, a comparison judgment processor 32B, a display processor 32C, and an output processor 32D. In the surface potential sensor 31, The surface potential of the measured wafer W can be confirmed. Hereinafter, each component of the controller 32 is demonstrated.

The input and correction processing unit 32A calculates an average value of the surface potentials based on the measurement signal input from the surface potential sensor 31 within a predetermined time, performs predetermined correction on the average value to obtain the original surface potential, and The processing signal indicative of the surface potential is transmitted to the comparison determination processing unit 32B. The comparison determination processing unit 32B compares the threshold value of the surface potential set in advance with the surface potential indicated by the input and correction signal from the correction processing unit 32A, and the surface potential is negative on the negative side and the threshold on the positive side. It is determined whether or not it is within the range (allowable range) of the signal, and the determination signal is transmitted to the display processing unit 32C. The display processing unit 32C executes a process for displaying the determination signal from the comparison determination processing unit 32B on the LED display unit 32E. The LED display portion 32E displays the surface potential within the allowable range and the surface potential not within the allowable range by color. It is also possible to use display means other than the LED display portion 32E. The output processing unit 32D outputs ON and OFF signals to the other output ports 32F and 32G depending on whether or not the surface potential indicated by the determination signal is within the allowable range, and is an analog signal via the D / A converter 32H. Output the surface potential. The output port 32F is turned on at the surface potential within the allowable range, and turned off at the other surface potential, and outputs respective ON and OFF signals. On the contrary, the output port 32G is turned off at the surface potential within the allowable range, and turned on at the other surface potential, and outputs the ON and OFF signals.

In addition, the controller 32 has a key input unit 32I as shown in FIG. 5. The key input section 32I is used to input a threshold value and the like.

Subsequently, an embodiment of the antistatic method of the present invention using the antistatic device 20 will be described with reference to FIGS. 6A to 6C. The antistatic method of the present invention is executed by executing a program for performing the method on a computer.

When the wafer W is to be inspected, the wafer conveyance mechanism is carried out from the housing by the wafer transport mechanism in the loader chamber 11, pre-aligns the sub-chuck, and then waits in the probe chamber 12. The wafer W is mounted (loaded) on the chuck 14. While the wafer W is loaded from the housing to the top plate 14A of the main chuck 14, as shown in FIG. 6A, the switch controller 26 is started to apply an electromotive force to the relay switch 23. do. When the electromotive force is applied to the relay switch 23, the switch 23B is closed, and the first conductor film 14C of the top plate 14A is connected to the center conductor 18A of the cable 18 and the wiring 22 for grounding. Ground via As a result, the static electricity charged on the top plate 14A is removed.

When the wafer transfer mechanism loads the wafer W on the top plate 14A, the main chuck 14 moves in the horizontal direction after vacuum suction of the wafer W on the top plate 14A. When the wafer W is adsorbed and fixed to the top plate 14A, the static electricity charged to the wafer W through the top plate 14A until then is removed via the top plate 14A. While the main chuck 14 is moving, the main chuck 14 cooperates with the alignment mechanism to perform the alignment of the wafer W and the probe 15A of the probe card 15. During this time, the static electricity tries to charge the wafer W and the top plate 14A, but since the top plate 14A is grounded, the wafer W and the top plate (until the wafer W is in contact with the probe 15A) Since the static electricity of 14A) is removed via the top plate 14A, the static electricity does not charge the wafer W.

However, in some cases, it is also assumed that static electricity is not sufficiently removed from the wafer W. If the static electricity is not sufficiently removed from the wafer W, and the charged wafer W is provided to the inspection as it is, the accurate inspection cannot be performed, and the device may be damaged depending on the state of charge. As part of the static elimination method, the charging check device 30 attached to the alignment bridge 40 is operated to check the charged state of the wafer W after the completion of the alignment. At this time, the main chuck 14 moves immediately below the surface potential sensor 31 of the charging check device 30, stops at a plurality of locations separated by a predetermined distance, respectively, and moves to the sensor unit 31A at each position. The charging potential of the wafer W is measured by When the surface potential sensor 31 measures the surface potential, the measurement signal is output to the controller 32 via the A / D converter 31B.

The measurement signal is input to the input of the controller 32 and to the correction processor 32A. The input and correction processing unit 32A calculates the average value of the surface potentials based on the measurement signal from the surface potential sensor 31, performs predetermined correction on the average value to obtain the original surface potential, and compares the processed signals. It transmits to the determination processing part 32B. The comparison determination processing unit 32B compares the threshold value of the surface potential set in advance with the surface potential indicated by the input and correction signal from the correction processing unit 32A, determines whether the surface potential is within the allowable range, and determines the determination. The signal is sent to the display processor 32C.

In the display processing unit 32C, the determination signal from the comparison determination processing unit 32B is signal processed, and the surface potential thereof is displayed on the LED display unit 32E. By looking at the LED display part 32E, the operator can easily confirm by the display color whether the current surface potential of the wafer W is within the allowable range, and can know the numerical value of the surface potential in detail.

The output processor 32D outputs an ON signal from the output port 32F when the surface potential indicated by the determination signal is within the allowable range, and outputs an OFF signal from the output port 32F when the surface potential is out of the allowable range. The output processor 32D outputs an OFF signal from the output port 32G when the surface potential indicated by the determination signal is within the allowable range, and outputs an ON signal from the output port 32G when the surface potential is out of the allowable range. In addition, the output processor 32D outputs the determination signal as an analog signal from the D / A converter 32H.

Therefore, when the wafer W after alignment is charged, the charging state of the wafer W can be confirmed simply and quickly by the charging check device 30. Depending on the charged state of the wafer W, the battery is charged again and the process proceeds to the inspection process.

After the wafer W is aligned, if the wafer W is not charged or is within the allowable range even if it is charged, the process proceeds to the next inspection process. In the inspection process, the first device in the wafer W is located directly under the probe 15A. At this position, the lifting mechanism 14B of the main chuck 14 is driven to raise the wafer W so that the device and the probe 15A are lifted up. Contact. Simultaneously with this contact, the switch controller 26 operates to lose the electromotive force of the relay switch 23, open the switch 23B, release the ground of the top plate 14A, and remove the ground from the wafer W and the top plate 14A. Stop the festival.

After the contact between the device and the probe 15A, the wafer W is overdriven through the lifting mechanism 14B of the main chuck 14, and the wafer W and the probe 15A are in electrical contact with each other, so that the probe card 15 is removed from the tester. The test signal is transmitted through the test head T, and at the same time, the first conductor film 14C on the upper surface of the top plate 14A is connected to the first conductor film 14C from the test head T via the center conductor 18A of the cable 18. Inspect the electrical characteristics of the device by applying a voltage. At this time, a voltage substantially equal to that of the first conductor film 14C is applied to the second conductor film 14D on the lower surface of the top plate 14A. Thereby, the leak current from 14 C of 1st conductor films can be suppressed, and the measurement precision of a device can be improved. In addition, since the second conductor film 14D on the lower surface of the top plate 14A is electrically connected to the case 23C via the first shield conductor 18B of the cable 18 and the wiring 22A, the grounding is performed. The switch 23B and the case 23C provided in the wiring 22 can be made substantially equipotential, and the leakage current and electrical noise from the ground wiring 22 and the switch 23B can be suppressed.

When the inspection of the first device is finished, the top plate 14A descends via the lifting mechanism 14B to release the contact between the device and the probe 15A. Simultaneously with this lowering operation, the relay switch 23 operates based on the command signal from the switch controller 26, closes the switch 23B, and grounds the first conductor film 14C of the top plate 14A. As shown in FIG. 6, the static electricity charged on the wafer W and the top plate 14A during the inspection is removed via the top plate 14A.

Then, the main chuck 14 moves in the X direction or the Y direction to index feed the wafer W, and after the next device reaches immediately below the probe 15A, the top plate 14A moves up and down 14B. Ascending through, the device and the probe 15A are in electrical contact. The static electricity of the wafer W and the top plate 14A is discharged through the top plate 14A between the lowering operation of the top plate 14A and the contact operation. At the same time as the contact between the device and the probe 15A, the relay switch 23 is operated based on the command signal from the switch controller 26 to open the switch 23B, and the static elimination from the top plate 14A is stopped. In this state, the test signal is transmitted from the test head T through the probe 15A, and the electric property test of the device described above is repeated.

When the inspection of the last device in the wafer W is finished, the top plate 14A is lowered. Simultaneously with this lowering operation, the switch 23B of the relay switch 23 is closed based on the command signal from the switch controller 26 to perform static elimination of the wafer W and the top plate 14A (see FIG. 6C). Then, the main chuck 14 moves to the loader chamber 11 side to receive the inspected and antistatic wafer W, and the wafer transfer mechanism waiting in the loader chamber 11 carries the wafer W on the main chuck 14. Unload After unloading the wafer W, the wafer transport mechanism returns the inspected wafer W to the storage portion, and then carries out the next wafer W from the storage portion.

In addition, the wafer transfer mechanism receives the wafer W to the main chuck 14 which waits for the wafer W pre-aligned in the subchuck in the prober chamber 12. After the wafer W is loaded on the main chuck 14, the above-described operations are repeated to inspect the wafer W, and the wafer W and the top plate 14A when the wafer W and the probe 15A are not in contact with each other. Perform the festival. In addition, by using a wafer transfer mechanism having two upper and lower arms, the wafer W is taken out from the housing portion by one arm, pre-aligned to wait for the inspected wafer W, and the inspected wafer W carries the wafer. When the mechanism is reached, the load may be executed on one arm after the wafer W is unloaded from the other arm.

As described above, since the static electricity of the wafer W and the top plate 14A is removed via the top plate 14A except when the wafer W and the probe 15A are in contact with each other, there is a great chance that the static electricity is charged on the wafer W. Since the amount of charges can be maintained to be substantially the same from the first device to the last device, there is no variation in the inspection result between the devices from the beginning to the end of the inspection, and the inspection can be performed with high reliability. In addition, since the amount of charge on the wafer W is small, there is no fear of damaging the device during inspection.

For example, even if the static charge of the wafer W just before the inspection is not sufficient, and the charge may exceed the allowable range, the charging abnormality of the wafer W can be confirmed immediately before the inspection using the charging confirmation device 30 immediately after the alignment. Therefore, a highly reliable inspection can be performed at all times without damaging the device during the inspection.

As described above, according to the present embodiment, the antistatic device 20 includes a grounding wire 22 for grounding the main chuck 14, a relay switch 23 provided in the grounding wire 22, and the relay. A switch controller 26 for opening and closing the switch 23 is provided, and the top plate of the main chuck 14 is closed by closing the relay switch 23 when the wafer W and the probe 15A are not in electrical contact. The process of removing the static electricity of the wafer W and the top plate 14A by grounding 14A) and opening the relay switch 23 when the wafer W and the probe 15A are in electrical contact with each other makes the top plate 14A Since the grounding process can be performed, almost no static electricity is accumulated on the wafer W during the inspection of the wafer W, and the reliability of the inspection can be improved even with the ultra-structure wafer W after the 65 nm process. It is possible to reliably prevent damage to the line structure.

In addition, according to the present embodiment, the top plate 14A of the main chuck 14 is connected to the test head T via the cable 18, and the grounding wiring 22 is the center conductor 18A of the cable 18. Since it is electrically connected to, the center conductor 18A of the cable 18 can be used as the grounding wiring of the static eliminator 20.

In addition, according to the present embodiment, since the first shield conductor 18B of the cable 18 is electrically connected to the storage case 23C of the relay switch 23 via the wiring 22A, the switch 23B By setting the case 23C at approximately equipotential, the leakage current and electrical noise from the grounding wiring 22 and the switch 23B can be suppressed. In addition, since the first shield conductor 18B of the cable 18 is connected to the second conductor film 14D on the lower surface of the top plate 14A, the first conductor film 14C is connected to the second conductor film 14D. The same voltage as?) Can be applied, whereby the leak current from the first conductor film 14C can be suppressed, and the measurement accuracy of the device can be increased. In addition, since the relay switch 23 is connected to the button switch 29 and is configured to be manually operated, an emergency evacuation is performed by operating the button switch 29 when an abnormality occurs due to static electricity during inspection. As a result, the static electricity of the wafer W can be removed.

In addition, according to the present embodiment, since the charging state of the wafer W is checked using the charging check device 30 immediately after alignment of the wafer W, the charging state of the wafer W can be confirmed immediately before the inspection, and the charging is abnormal. If not, the test can be run as is. If the wafer W has a charging abnormality, the static elimination process can be carried out before the inspection, and a highly reliable inspection can be executed, and damage to the device due to the charging abnormality at the time of inspection can be prevented.

In addition, according to the present embodiment, since the charging confirmation device 30 has a key input unit 32I for setting the allowable range of the charging potential of the wafer W, the comparison determination processing unit 32B is based on the threshold value. It is possible to determine whether or not the charging potential of is normal. Since the determination result of the comparison determination processing unit 32B is displayed on the LED display unit 32E via the display processing unit 32C, the operator can confirm the degree of charging of the wafer W by the LED display unit 32E. When the determination result in the comparison determination processing unit 32B is outside the allowable range of the charging potential of the wafer W, it is displayed on the LED display unit 32E, and countermeasures such as electrostatic discharge can be taken.

In addition, although the said embodiment demonstrated the inspection apparatus which a main chuck (mounting stage) moves with respect to a probe card, the inspection apparatus which a probe card moves with respect to a mounting board may be sufficient. In addition, in the said embodiment, although the antistatic apparatus applied to the inspection apparatus which inspects the wafer W was demonstrated, this invention is applicable also to inspection apparatuses other than a wafer. In addition, in the said embodiment, although a static electricity elimination apparatus is attached to the alignment bridge and charge confirmation is performed immediately after alignment, you may carry out at an appropriate timing as needed. In addition, as long as the site | part of attachment of an antistatic device is a site | part which can confirm the surface potential of the test subject surface, it is not restrict | limited to the alignment bridge.

This invention can be used suitably for the test | inspection apparatus of the semiconductor manufacturing field.

BRIEF DESCRIPTION OF THE DRAWINGS The front view which partially fractures and shows an example of the structure of the test | inspection apparatus to which one Embodiment of the antistatic device of this invention was applied.

FIG. 2 is a cross-sectional view showing a top plate of the inspection device shown in FIG. 1. FIG.

FIG. 3 is a block diagram showing the antistatic device shown in FIG. 1. FIG.

4 is a block diagram showing a charging check device attached to an alignment bridge of the inspection device shown in FIG. 1;

FIG. 5 is a block diagram showing a controller of the game check apparatus shown in FIG. 4. FIG.

6A to 6C are timing diagrams each showing a method of destaticizing a wafer.

<Description of the symbols for the main parts of the drawings>

10... Inspection apparatus 14. Main chuck (mounting stand)

14A... Top Plate 14C... First conductor film

14D... Second conductor film 15... Probe card

15A... Probe 18... cable

20... Antistatic device 22. Grounding Wiring

23... Relay switch 23C... case

26... Switch controller 30.. Antistatic device

32B... Comparison judgment processing unit (means for determining that it is outside the allowable range of the charging potential)

32I... Key input unit (means for setting the allowable range of charging potential)

W wafer

Claims (20)

The mounting table of the inspected object and the probe card move relatively, the inspected object of the mounting object and the probe card are in electrical contact with each other, and the electrical characteristics of the inspected object are inspected. In the antistatic device for removing static electricity, A grounding wire for grounding the mount; A relay switch provided in the grounding wiring; A switch controller for opening and closing the relay switch during execution of an electrical characteristic test of the inspected object Antistatic device comprising a. When the mounting table of the inspected object and the probe card are relatively moved, and the inspected object of the mounting object and the probe card are in electrical contact with each other to perform the electrical characteristics and inspection of the inspected object, In the antistatic device for removing static electricity, A grounding wire for grounding the mount; A relay switch provided in the grounding wiring, Switch controller to open and close this relay switch Including but not limited to: The mounting table has a top plate serving as a mounting surface of the test object, and the grounding wiring is connected to a first-first conductor film formed on an upper surface of the top plate. The method of claim 2, The mounting table is connected to a test head through a cable, and the grounding wire is electrically connected to a center conductor of the cable. The method of claim 3, wherein The external conductor of the cable is electrically connected to a second conductor film formed on the lower surface of the top plate. The method of claim 4, wherein The external conductor of the cable is connected to the housing of the relay switch via wiring. The method according to any one of claims 1 to 5, The relay switch is an antistatic device, characterized in that configured to be manual operation. The method according to claim 1 or 2, An antistatic device comprising a charging check device for checking a charging state of the inspected object. The method of claim 7, wherein And the charge confirming device has a key input section for setting an allowable range of charging potential. The method of claim 8, The antistatic device according to claim 1, wherein the charge confirmation device has a comparison determination processing unit that determines that the charge potential is out of an allowable range. The method of claim 8, And the charge confirming device has an LED display portion for displaying the charge potential. When the mounting table on which the test object is mounted and the probe card are relatively moved, and the test object mounted on the mounting target and the probe card are in electrical contact with each other to perform the electrical property test of the test object, In the method of removing the static electricity of the object under test using a relay switch provided in the wiring, A first step of grounding the mounting table and removing static electricity of the inspected object by closing the relay switch when the inspected object and the probe card are not in electrical contact; A second step of releasing the ground of the mount by opening the relay switch when the object under test and the probe card are in electrical contact with each other; Antistatic method comprising a. The method of claim 11, And the first step is a step in which the probe card and the mount are relatively moved. The method of claim 11, The first step includes a step of mounting the inspected object on the mounting target, and a process of aligning the inspected object with the probe card. The method of claim 11 And the first step includes removing the inspected object from the mounting target. The method of claim 11, The said 2nd process is a static electricity elimination method characterized by the process of the said mounting table overdrivening the to-be-tested object. The method according to any one of claims 11 to 15, And a step of checking a state of charge of the inspected object. The method of claim 16, And the step of checking the charged state is a post-process of the alignment process. When the computer is driven to relatively move the mounting table and the probe card on which the test object is mounted, and the test object to be mounted is electrically contacted with the probe card to perform the electrical property test of the test object. A recording medium having recorded thereon a program for executing a method for removing static electricity of a subject under test by using a relay switch provided in a grounding wiring, A first step of grounding the mounting table and removing static electricity of the inspected object by closing the relay switch when the inspected object and the probe card are not in electrical contact; A second step of releasing the ground of the mount by opening the relay switch when the object under test and the probe card are in electrical contact with each other; And a program recording medium. The method of claim 18, And a third step of checking a state of charge of the object under test. The method of claim 9, And the charge confirming device has an LED display portion for displaying the charge potential.

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