JP2011033549A - Inspection method of probe card, inspection method of semiconductor device and probe card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection method of a probe card, which enables a user to correctly know a replacement time of the probe card, based on a result of a conduction test in the probe card. <P>SOLUTION: The inspection method of the probe card attached to a semiconductor inspection apparatus for electrically testing a chip area formed in a semiconductor wafer has: a conduction test process for bringing an electrode terminal in the chip area into contact with a probe needle of the probe card, flowing a current in the chip area, and measuring a voltage value; a calculation process for calculating a standard deviation of the measured voltage value; and a determination process for determining whether a standard deviation value is within a predetermined range or not. If the standard deviation value exceeds the predetermined range, a display provided in the probe card informs the user of a replacement of the probe card attached to the semiconductor inspection apparatus with a new probe card. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a probe card inspection method, a semiconductor device inspection method, and a probe card.

  The probe card is mainly used for a test in a chip state in a wafer state before an assembly process of LSI (Large Scale Integration) manufacture. The probe card has a probe needle that is brought into contact with an electrode portion such as an Al pad, a gold bump, or a solder bump in a chip region that is a measurement region, and is used by being attached to a prober that is a semiconductor inspection apparatus.

  The prober inputs a test signal or test pattern from the probe needle of the probe card to the electrode area of the chip area, and inspects the chip area in the wafer state based on the output signal obtained from another electrode area of the chip area. Is what you do.

  The probe needle of the probe card is brought into contact with the electrode portion in the chip area in the wafer state by applying a predetermined pressure every time inspection is performed. For this reason, a problem has occurred due to repeated use and the tip of the probe needle being gradually scraped by contact with the electrode portion in the tip region. As an example of the problem, the contact state with the electrode portion in the tip region gradually decreases, and good electrical continuity cannot be obtained between the probe needle and the electrode portion in the tip region. Therefore, an accurate inspection cannot be performed in the chip area in the wafer state, which is one factor that causes a decrease in yield.

  For this reason, generally, a method is used in which a probe card that exceeds a predetermined number of uses is replaced with a new probe card.

JP 2000-200121 A JP 2006-128452 A

  By the way, as described above, when managing with the use frequency and exchanging with a new probe card, it is necessary to record and manage the number of contacts in each probe card (number of contacts with the electrode part in the chip area of the wafer) in a ledger or the like. There is. Therefore, the expense and time for management were required.

  When setting and managing the number of contacts, probe cards that have reached a certain number of contacts are uniformly replaced. Therefore, even if it is a probe card that can still be used, it will be replaced with a new probe card, or even if it is already in a poor contact state with the electrode part, a certain number of contacts It may not be exchanged until In particular, when the contact state with the electrode portion is not good before reaching a certain number of contacts, it is impossible to perform an accurate inspection in the chip state of the wafer state, and a semiconductor device such as an LSI to be manufactured This leads to a decrease in yield. In order to avoid this, if the value of the number of contacts set for replacing the probe card is lowered, a probe card that can still be used will be replaced, which increases the manufacturing cost of the semiconductor device. End up.

  Therefore, the usable probe card can be used for as long as possible, and the probe card whose probe needle has been cut and the contact state with the electrode portion in the chip region is lowered can be immediately replaced with a new probe card. A method was desired.

  According to one aspect of the present embodiment, in an inspection method for a probe card attached to a semiconductor inspection apparatus for performing an electrical test in a chip region formed on a semiconductor wafer, an electrode terminal in the chip region; A continuity test step of contacting a probe needle of the probe card and passing a current through the chip region to measure a voltage value, a calculating step of calculating a standard deviation of the measured voltage value, and a value of the standard deviation A determination step of determining whether or not the value is within a predetermined range, and if the value of the standard deviation exceeds a predetermined range, the semiconductor inspection is performed on the display unit provided on the probe card. Inform the user that the probe card attached to the apparatus is to be replaced with a new probe card.

  Further, according to another aspect of the present embodiment, in the inspection method of the semiconductor device in the chip region formed on the semiconductor wafer, the electrode terminal in the chip region and the probe needle of the probe card are brought into contact, A continuity test step of passing a current through the chip region and measuring a voltage value; a calculation step of calculating a standard deviation of the measured voltage value; and determining whether the value of the standard deviation is within a predetermined range When the determination step and the value of the standard deviation are within a predetermined range, an inspection is performed by inputting an input signal to the chip area via the probe card and detecting an output signal from the chip area. An inspection step, and when the standard deviation value exceeds a predetermined range, the display unit provided in the probe card is attached to the semiconductor inspection apparatus. Notifying the exchange of the probe card and the new probe card.

  Further, according to another aspect of the present embodiment, in a probe card attached to a semiconductor inspection apparatus for performing an electrical test in a chip region formed on a semiconductor wafer, an electrode terminal in the chip region; When the probe needle of the probe card is contacted, a current is passed through the chip area to measure a voltage value, a standard deviation of the measured voltage value is calculated, and the standard deviation value exceeds a predetermined range Has a display section for notifying that the probe card attached to the semiconductor inspection apparatus is to be replaced with a new probe card.

  According to the disclosed probe card inspection method, semiconductor device inspection method, and probe card, when the tip of the probe needle is shaved and can no longer be used, the probe card is informed that this has occurred. it can. Thereby, it can be exchanged for a new probe card. As a result, a semiconductor device can be manufactured at a low cost without causing a decrease in yield.

Configuration diagram of semiconductor test equipment Logic tester configuration diagram Probe card configuration diagram Explanatory drawing of the contact state of the probe needle to the electrode terminal on the semiconductor wafer Histogram of voltage value in continuity test of new probe card Histogram of voltage value in continuity test of probe card used for several months Correlation diagram of probe card contact count and voltage value σ value in continuity test Flowchart of the semiconductor inspection method in the first embodiment Flowchart of semiconductor inspection method according to second embodiment

  The form for implementing is demonstrated below.

[First Embodiment]
(Semiconductor inspection equipment)
A first embodiment will be described. First, the semiconductor inspection apparatus in this embodiment will be described.

  A semiconductor inspection apparatus according to the present embodiment will be described with reference to FIG. The semiconductor inspection apparatus according to the present embodiment includes a logic tester 10 and a prober 20, and the logic tester 10 and the prober 20 are electrically connected via a cable 21.

  Next, the logic tester 10 will be described with reference to FIG. The logic tester 10 includes an I / F unit 11, an inspection unit 12, a control unit 15, and a nonvolatile memory 16.

  The I / F unit 11 is for performing electrical signal communication with the prober 20 via the cable 21.

  The inspection unit 12 includes a signal generation unit 13 that generates an electrical signal for inspecting the chip region of the semiconductor wafer, and a signal inspection unit 14 that performs inspection based on the electrical signal obtained from the chip region of the semiconductor wafer. is doing. For this reason, the inspection unit 12 includes a pulse generator serving as a signal generation source, a plurality of power supplies, a plurality of comparators that perform inspection based on electrical signals obtained from the chip region of the semiconductor wafer, and the like.

  The electrical signal generated by the signal generation unit 13 is output to the prober 20 via the I / F unit 11, the electrical signal from the prober 20 is input via the I / F unit 11, and the signal inspection unit 14 performs inspection. Is called.

  The control unit 15 is for controlling the entire prober 20 and controls the I / F unit 11, the inspection unit 12, the nonvolatile memory 16, and the like.

  The nonvolatile memory 16 is formed of a hard disk or the like, and can retain the stored state even when the power of the semiconductor inspection apparatus is turned off.

  On the other hand, in the prober 20, a probe card 30 is connected via a test board 22. The probe card 30 inspects a chip area in a semiconductor wafer 40 such as an LSI while being attached in the prober 20. The probe card 30 is electrically connected to the prober 20 in a detachable state, and the semiconductor wafer 40 to be inspected is installed in the prober 20.

  Next, the probe card 30 will be described with reference to FIG. The probe card 30 includes a probe needle unit 31, an I / F unit 32, a control unit 33, a nonvolatile memory 34, an LED 35 serving as a display unit, and the like.

  The probe needle portion 31 is formed by a plurality of probe needles, and as described above, is electrically connected by contacting each electrode terminal in the chip region of the semiconductor wafer 40 to be inspected.

  The I / F unit 32 is for communicating electrical signals with the prober 20 body via the test board 22. The electrical signal generated in the logic tester 10 is input via the I / F unit 32, and the electrical signal obtained from the chip area of the semiconductor wafer is output to the prober 20 main body and further to the logic tester 10 via the I / F unit 32. To do.

  The control unit 33 controls the entire probe card 30 and controls the I / F unit 32, the nonvolatile memory 34, and the like. The control unit 33 includes a microcomputer and peripheral circuits for control.

  The non-volatile memory 34 is formed of a flash memory or the like, and can retain memory even when no power is supplied to the probe card 30.

  The LED 35 notifies that the probe card 30 needs to be replaced, and lights up based on the control of the control unit 33. Note that it is possible to display that the probe card 30 needs to be replaced by another display method instead of the LED 35.

  The probe card 30 is provided with a plurality of probe needles 31a as shown in FIG. 4. When inspecting the chip area of the semiconductor wafer 40, the electrode terminals 41 and the probe needles 31a in the chip area of the semiconductor wafer 40 are provided. It is performed in a state of contact at the tip. In this state, the probe needle 31a and the electrode terminal 41 in the tip region are electrically connected. However, as the number of contacts with the electrode terminal 41 increases, the tip of the probe needle 31a is shaved, and good contact with the electrode terminal 41 cannot be maintained, and a high resistance is generated between the probe needle 31a and the electrode terminal 41. May occur.

  This will be described in more detail with reference to FIGS. 5 and 6 show the results of the continuity test. In the continuity test performed in the present embodiment, a predetermined current is applied to the diode formed in the chip region of the semiconductor wafer 40 via the probe card 30 and the terminal voltage of the diode in this state is measured. It was done by.

  FIG. 5 shows a histogram of voltage values and frequency of occurrence when conducting a continuity test on a new probe card. In the case of a new probe card, since the tips of all the probe needles are surely in contact with the electrode terminals provided on the semiconductor wafer, a uniform voltage value can be obtained. FIG. 6 shows a histogram of voltage values and frequency of occurrence when conducting a continuity test on a probe card used for several months. By using the probe card, the tip of the probe needle is scraped, the contact state with the electrode terminal provided on the semiconductor wafer is not good, the resistance increases between the tip of the probe needle and the electrode terminal, and the voltage value is increased. Variations occur. In such a state, accurate inspection in the chip region of the semiconductor wafer cannot be performed, and the yield of semiconductor devices such as LSIs to be manufactured is reduced.

  Next, FIG. 7 shows the relationship between the number of contacts in the probe card and the standard deviation σ of the voltage value measured in the continuity test. In general, as shown in the figure, as the number of contacts with the electrode terminals on the semiconductor wafer in the probe card increases, the standard deviation σ measured in the continuity test increases, The variation in the detected voltage value tends to increase.

  In the semiconductor inspection apparatus according to the present embodiment, when the value of the standard deviation σ exceeds a reference value, the LED 35 provided on the probe card 30 is lit and the probe card 30 needs to be replaced. Is displayed.

(Probe card inspection method and semiconductor device inspection method)
Next, a probe card inspection method and a semiconductor device inspection method in this embodiment will be described.

  FIG. 8 is a flowchart of a semiconductor device inspection method including the probe card inspection method according to the present embodiment.

  First, as shown in step 102 (S102), the probe card 30 is checked. Specifically, the probe card 30 is inspected for any deposits or the like at the tip of the probe needle.

  Next, as shown in step 104 (S104), the semiconductor wafer 40 is set in the prober 20. Specifically, the semiconductor wafers 40 in the prober 20 are installed by sorting. After the semiconductor wafer 40 is placed at a predetermined position in the prober 20, the probe needles in the probe card 30 come into contact with the electrode terminals formed in the chip region of the semiconductor wafer 40 and are electrically connected.

  Next, as shown in step 106 (S106), a continuity test of the probe card is performed. Specifically, an electric current is passed through the diode formed in the chip region of the semiconductor wafer 40 via the probe needle in the probe card 30.

  Next, as shown in step 108 (S108), it is determined whether or not the continuity test is properly performed. For example, in a state where the probe needles in the probe card 30 are not in contact with the electrode terminals in the chip region of the semiconductor wafer 40, the continuity test is not performed properly, so the probe card 30 cannot be inspected. In this case, since no current can flow through the diode or the like, the voltage cannot be detected via the probe card 30. Therefore, this determination is made based on whether or not a predetermined voltage value is detected via the probe card 30. When it is determined that the continuity test is not properly performed, the process proceeds to step 110. On the other hand, if it is determined that the continuity test is properly performed, the process proceeds to step 112. This determination is made in the logic tester 10.

  In step 110 (S110), the semiconductor wafer 40 is set up again. For example, when it is determined that the continuity test is not properly performed, the semiconductor wafer 40 may not be installed at a predetermined position. Therefore, the semiconductor wafer 40 is set up again. Specifically, the semiconductor wafer 40 is unloaded from the prober 20 for re-setup, and then the semiconductor wafer 40 is sorted again. Thereafter, the process proceeds to step 104.

  Next, as shown in step 112 (S112), the chip area of the semiconductor wafer 20 installed on the semiconductor wafer 20 installed on the prober 20 is inspected. By this inspection, the quality of the chip area in the semiconductor wafer 20 is determined.

  Next, as shown in step 114 (S114), a σ value that is a standard deviation of the voltage value obtained in the continuity test performed in step 106 is calculated. Specifically, the σ value of the voltage value obtained based on the continuity test is calculated in the signal inspection unit 14 or the like of the logic tester 10. The voltage value obtained in this continuity test is stored in the nonvolatile memory 16.

  Next, as shown in step 116 (S116), the σ value is transferred from the logic tester 10 to the probe card 30.

  Next, as shown in step 118 (S118), it is determined whether or not the σ value is within a predetermined range. Specifically, as shown in FIG. 7, as the number of contacts increases, the σ value increases. Therefore, a predetermined value serving as a reference for exchanging the probe card is provided, and whether the σ value is equal to or less than the predetermined value. It is judged by. If the σ value is within the predetermined range, the process ends. On the other hand, if the σ value exceeds the predetermined range, the process proceeds to step 120. In the present embodiment, this determination is made by the control unit 33 in the probe card 30.

  Next, as shown in step 120 (S120), maintenance is performed. Specifically, as an example of the display method, an LED 35 provided on the probe card 30 is turned on to inform that replacement with a new probe card is necessary. Based on this information, the measurer exchanges a probe card attached to the prober 20 with a new probe card. After the replacement, the process proceeds to step 104.

  As described above, the inspection of the chip region of the semiconductor wafer to be the semiconductor device in the present embodiment is completed. In this embodiment, since each probe card 30 is judged as good or bad individually, it can be used until the lifetime of each probe card is reached. Therefore, a semiconductor device to be inspected can be manufactured at a lower cost.

[Second Embodiment]
Next, a second embodiment will be described. The present embodiment is a probe card inspection method and a semiconductor device inspection method different from those of the first embodiment.

  FIG. 9 is a flowchart of a semiconductor device inspection method including a probe card inspection method according to the present embodiment.

  First, as shown in step 202 (S202), the probe card 30 is checked. Specifically, the probe card 30 is inspected for any deposits or the like at the tip of the probe needle.

  Next, as shown in step 204 (S204), the semiconductor wafer 40 is set in the prober 20. Specifically, the semiconductor wafers 40 in the prober 20 are installed by sorting. After the semiconductor wafer 40 is placed at a predetermined position in the prober 20, the probe needles in the probe card 30 come into contact with the electrode terminals formed in the chip region of the semiconductor wafer 40 and are electrically connected.

  Next, as shown in step 206 (S206), a continuity test of the probe card is performed. Specifically, an electric current is passed through the diode formed in the chip region of the semiconductor wafer 40 via the probe needle in the probe card 30.

  Next, as shown in step 208 (S208), it is determined whether or not the continuity test is properly performed. For example, in a state where the probe needles in the probe card 30 are not in contact with the electrode terminals in the chip region of the semiconductor wafer 40, the continuity test is not performed properly, so the probe card 30 cannot be inspected. In this case, since no current can flow through the diode or the like, the voltage cannot be detected via the probe card 30. Therefore, this determination is made based on whether or not a predetermined voltage value is detected via the probe card 30. When it is determined that the continuity test is not properly performed, the process proceeds to step 210. On the other hand, if it is determined that the continuity test is properly performed, the process proceeds to step 212. This determination is made in the logic tester 10. That is, the voltage value obtained from the result of the continuity test performed in step 206 is transmitted to the logic tester 10, and the determination in step 208 is made in the logic tester 10.

  In step 210 (S210), the semiconductor wafer 40 is set up again. For example, when it is determined that the continuity test is not properly performed, the semiconductor wafer 40 may not be installed at a predetermined position. Therefore, the semiconductor wafer 40 is set up again. Specifically, the semiconductor wafer 40 is unloaded from the prober 20 for re-setup, and then the semiconductor wafer 40 is sorted again. Thereafter, the process proceeds to step 204.

  Next, as shown in step 212 (S212), the chip area of the semiconductor wafer 20 installed on the semiconductor wafer 20 installed on the prober 20 is inspected. By this inspection, the quality of the chip area in the semiconductor wafer 20 is determined.

  Next, as shown in step 214 (S214), the voltage value obtained based on the continuity test performed in step 206 is transferred from the logic tester 10 to the probe card 30. The voltage value obtained based on the continuity test is also stored in the nonvolatile memory 16 in the logic tester 10.

  Next, as shown in step 216 (S216), the voltage value transferred from the logic tester 10 to the probe card 30, that is, the standard deviation of the voltage value obtained based on the continuity test performed in step 206 is σ. The value is calculated. Specifically, the control unit 33 of the probe card 30 calculates the σ value of the voltage value obtained based on the continuity test.

  Next, as shown in step 218 (S218), it is determined whether or not the σ value is within a predetermined range. Specifically, as shown in FIG. 7, as the number of contacts increases, the σ value increases. Therefore, a predetermined value serving as a reference for exchanging the probe card is provided, and whether the σ value is equal to or less than the predetermined value. Judgment by If the σ value is within the predetermined range, the process ends. On the other hand, if the σ value exceeds the predetermined range, the process proceeds to step 218. In the present embodiment, this determination is made by the control unit 33 in the probe card 30.

  Next, as shown in step 220 (S220), maintenance is performed. Specifically, as an example of the display method, an LED 35 provided on the probe card 30 is turned on to inform that replacement with a new probe card is necessary. Based on this information, the measurer exchanges a probe card attached to the prober 20 with a new probe card. After the replacement, the process proceeds to step 204.

  As described above, the inspection of the chip region of the semiconductor wafer to be the semiconductor device in the present embodiment is completed. In the present embodiment, whether each probe card 30 is good or bad is determined for each probe card 30 and can be used until the lifetime of each probe card is reached. Therefore, a semiconductor device to be inspected can be manufactured at a lower cost.

  As described above, the inspection of the chip region of the semiconductor wafer to be the semiconductor device in the present embodiment is completed. In the present embodiment, the quality of each probe card 30 is determined individually, so that each probe card can be used until the end of its life. Therefore, the semiconductor device to be inspected can be manufactured at a lower cost.

  Although the embodiment has been described in detail above, it is not limited to the specific embodiment, and various modifications and changes can be made within the scope described in the claims.

Regarding the above description, the following additional notes are disclosed.
(Appendix 1)
In an inspection method of a probe card attached to a semiconductor inspection apparatus for performing an electrical test on a chip region formed on a semiconductor wafer,
A continuity test step of contacting the electrode terminal in the chip region and the probe needle of the probe card and passing a current through the chip region to measure a voltage value;
A calculation step of calculating a standard deviation of the measured voltage value;
A determination step of determining whether the value of the standard deviation is within a predetermined range;
When the value of the standard deviation exceeds a predetermined range, the display unit provided on the probe card replaces the probe card attached to the semiconductor inspection apparatus with a new probe card. A method for inspecting a probe card, characterized by notifying.
(Appendix 2)
The semiconductor inspection apparatus has a logic tester and a prober to which the probe card is attached,
The probe card inspection method according to claim 1, wherein the calculation step is performed in the logic tester.
(Appendix 3)
2. The probe card inspection method according to claim 1, wherein the calculation step is performed in the probe card.
(Appendix 4)
4. The probe card inspection method according to any one of appendices 1 to 3, wherein the determination step is performed in the probe card.
(Appendix 5)
In an inspection method of a semiconductor device in a chip region formed on a semiconductor wafer,
A continuity test step of measuring a voltage value by causing an electric current to flow in the chip region by bringing an electrode terminal in the chip region into contact with a probe needle of a probe card;
A calculation step of calculating a standard deviation of the measured voltage value;
A determination step of determining whether the value of the standard deviation is within a predetermined range;
When the value of the standard deviation is within a predetermined range, an inspection process for performing an inspection by inputting an input signal to the chip area through the probe card and detecting an output signal from the chip area;
When the value of the standard deviation exceeds a predetermined range, the display unit provided on the probe card replaces the probe card attached to the semiconductor inspection apparatus with a new probe card. A method for inspecting a semiconductor device, characterized by:
(Appendix 6)
The semiconductor inspection apparatus has a logic tester and a prober to which the probe card is attached,
6. The method of inspecting a semiconductor device according to appendix 5, wherein the calculation step is performed in the logic tester.
(Appendix 7)
6. The method for inspecting a semiconductor device according to appendix 5, wherein the calculation step is performed in the probe card.
(Appendix 8)
8. The semiconductor device inspection method according to any one of appendices 5 to 7, wherein the determination step is performed in the probe card.
(Appendix 9)
In a probe card attached to a semiconductor inspection apparatus for performing an electrical test in a chip region formed on a semiconductor wafer,
Contact the electrode terminal in the chip region and the probe needle of the probe card, flow a current through the chip region, measure the voltage value, calculate the standard deviation of the measured voltage value,
A probe card comprising a display unit for notifying that the probe card attached to the semiconductor inspection apparatus is to be replaced with a new probe card when the value of the standard deviation exceeds a predetermined range.
(Appendix 10)
The display unit includes an LED,
The probe card according to appendix 9, wherein the LED is lit to notify that the probe card is to be replaced with a new probe card.

DESCRIPTION OF SYMBOLS 10 Logic tester 11 I / F part 12 Inspection part 13 Signal generation part 14 Signal inspection part 15 Control part 16 Non-volatile memory 20 Prober 21 Cable 22 Test board 30 Probe card 31 Probe needle part 31a Probe needle 32 I / F part 33 Control Part 34 nonvolatile memory 40 semiconductor wafer 41 electrode terminal

Claims (5)

In an inspection method of a probe card attached to a semiconductor inspection apparatus for performing an electrical test on a chip region formed on a semiconductor wafer,
A continuity test step of contacting the electrode terminal in the chip region and the probe needle of the probe card and passing a current through the chip region to measure a voltage value;
A calculation step of calculating a standard deviation of the measured voltage value;
A determination step of determining whether the value of the standard deviation is within a predetermined range;
When the value of the standard deviation exceeds a predetermined range, the display unit provided on the probe card replaces the probe card attached to the semiconductor inspection apparatus with a new probe card. A method for inspecting a probe card, characterized by notifying.   The probe card inspection method according to claim 1, wherein the determination step is performed in the probe card. In an inspection method of a semiconductor device in a chip region formed on a semiconductor wafer,
A continuity test step of measuring a voltage value by causing an electric current to flow in the chip region by bringing an electrode terminal in the chip region into contact with a probe needle of a probe card;
A calculation step of calculating a standard deviation of the measured voltage value;
A determination step of determining whether the value of the standard deviation is within a predetermined range;
When the value of the standard deviation is within a predetermined range, an inspection process for performing an inspection by inputting an input signal to the chip area through the probe card and detecting an output signal from the chip area;
When the value of the standard deviation exceeds a predetermined range, the display unit provided on the probe card replaces the probe card attached to the semiconductor inspection apparatus with a new probe card. A method for inspecting a semiconductor device, characterized by:   The semiconductor device inspection method according to claim 3, wherein the determination step is performed in the probe card. In a probe card attached to a semiconductor inspection apparatus for performing an electrical test on a chip area formed on a semiconductor wafer,
Contact the electrode terminal in the chip region and the probe needle of the probe card, flow a current through the chip region, measure the voltage value, calculate the standard deviation of the measured voltage value,
A probe card comprising a display unit for notifying that the probe card attached to the semiconductor inspection apparatus is to be replaced with a new probe card when the value of the standard deviation exceeds a predetermined range.

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