KR20170049880A - Method of aligning probe card - Google Patents

Abstract

A probe card alignment method for aligning a probe card with respect to a substrate is disclosed. First, a probe card having a plurality of probes for inspecting electrical characteristics is disposed on a substrate on which a plurality of dies are formed. The substrate is placed facing the probe card. Then, the probe card is leveled with respect to the substrate based on contact information, which is an electrical signal outputted from each die, by contacting the probes with the substrate, and the contact failure between the probes and the dies is detected by each die through the contact information Level the probe card. As such, the probe card alignment method can level the probe card by grasping the contact failure with the probe for each of the dies, so that the deviation in the probe card can be accurately corrected and the probes can be uniformly connected to the dies .

Description

Method of aligning probe card [

Embodiments of the present invention relate to a probe card alignment method. And more particularly to a method of aligning a probe card with respect to a wafer in a probe station for electrical characterization of a wafer on which semiconductor devices are formed.

Generally, semiconductor devices, such as integrated circuit devices, can be formed by repeatedly performing a series of semiconductor processes on a substrate, such as a semiconductor wafer. For example, a deposition process for forming a thin film on a wafer, an etching process for forming the thin film into patterns having electrical characteristics, an ion implantation process or diffusion process for implanting or diffusing impurities into the patterns, Semiconductor circuits, i.e., dies, can be formed on the substrate by repeatedly performing cleaning and rinsing processes to remove impurities from the substrate.

An inspection process for inspecting the electrical characteristics of the dies after forming the dies through such a series of processes can be performed. The inspection process may be performed by a probe station including a probe card having a plurality of probes and a tester connected to the probe card to provide an electrical signal.

A probe card may be mounted on the upper part of the inspection chamber, and a stage supporting the wafer may be disposed below the probe card. The stage may be configured to be movable vertically and horizontally so that the dies contact the probes of the probe card.

An alignment step may be performed to align the wafer and the probe card so that the probes of the probe card are electrically conductive with the dies before performing this inspection process.

The steps of aligning the probe card and the wafer are as follows. First, a predetermined probe among the probes of the probe card is detected at a predetermined coordinate using a lower camera, and a preset alignment pattern on the wafer is detected at a predetermined coordinate using an upper camera. The position of the wafer can then be adjusted using the detected coordinates of the detected probe and alignment pattern. Subsequently, the electrode pads of the wafer are raised to bring the probes of the probe card into contact with each other, and the alignment state of the wafer can be confirmed using the contact marks formed by the contact of the probes and the electrode pads.

However, since the leveling of the probe card with respect to the wafer is performed only for a predetermined part of the probes of the probes, it is difficult to correct the deflection of the probe when the probe is deflected, It may not be possible.

Also, the tip height of the probes may be slightly different from each other, and the tip height difference of the probes and the surface uniformity of the wafer affect the parallelism of the wafer and the probe card, so that some probes may not contact the electrode pads The electrode pads may be damaged by pressing the electrode pads too deeply.

Korean Patent Registration No. 10-0964744 (Jun. 10, 2010) Korean Registered Patent No. 10-1083346 (November 8, 2011)

It is an object of the present invention to provide a probe card alignment method capable of accurately and easily leveling a probe card with respect to a substrate in a probe station.

According to an aspect of the present invention, there is provided a probe card alignment method comprising: disposing a probe card having a plurality of probes for inspecting electrical characteristics of a substrate on which a plurality of dies are formed; Facing the card, and leveling the probe card relative to the substrate based on contact information, the electrical signal being output from each die, by contacting the probes with the substrate, wherein contact between the probes and the dies And leveling the probe card by detecting defects by the respective dies through the contact information.

According to embodiments of the present invention, the step of leveling the probe card using the contact information may include contacting the probes with electrode pads of the dice at a predetermined first contact depth, Detecting the contact failure between the probe and the electrode pad corresponding to each other through the contact information output from each of the dice corresponding to the alignment signal, A step of judging whether or not there is a die in which a contact defect occurs in the die, and a step of judging whether or not there is a die in which a contact defect occurs, And adjusting the tilt angle and direction of the probe card.

According to embodiments of the present invention, the step of leveling the probe card using the contact information may include a step of determining whether there is a die where the contact failure occurs before the step of adjusting the tilt angle and direction of the probe card Determining whether there is a die normally in contact with a corresponding one of the dies if it is determined that there is a die in which the contact failure occurs, and in the step of determining whether there is a normally contacted die, And adjusting the contact depth of the probes to a second contact depth that is deeper than the first contact depth if no contact depth is present. In addition, after the step of adjusting the contact depth of the probes, the alignment signal may be sequentially performed again from the step of applying the alignment signal to the test pads.

According to embodiments of the present invention, the step of determining whether there is a die in which the contact defect occurs may include determining whether or not the output contact information value corresponds to the output threshold value, which is output when the probe and the electrode pad normally contact each other, Value, it can be determined that a contact failure has occurred in the die outputting the low contact information value.

According to embodiments of the present invention, the step of adjusting the tilt angle and direction of the probe card may include adjusting the tilt angle of the probe card according to the difference between the contact information value of the die where the contact failure occurs and the output threshold value, And direction can be adjusted.

According to embodiments of the present invention, the contact information may be a current value output from the die corresponding to the alignment signal.

According to the embodiments of the present invention, the probe card aligning method may include a step of checking the position of the probes of the probe card with the camera before leveling the probe card using the contact information, The method comprising the steps of:

According to the embodiments of the present invention as described above, the probe card alignment method can level the probe card by grasping the contact failure with the probe for each of the dies, so that the deviation in the probe card can be accurately corrected, Can be connected to the dies uniformly. As a result, electrical inspection of the substrate using the probe card can be performed stably and the reliability of inspection can be improved.

1 is a schematic configuration diagram for explaining a probe station.
Fig. 2 is a schematic plan view for explaining the card holder shown in Fig. 1. Fig.
3 is a schematic plan view for explaining a die formed in the substrate shown in Fig.
4 is a flowchart illustrating a method of aligning a probe card according to an embodiment of the present invention.
5 is a flowchart for explaining the probe card leveling step shown in FIG.
FIG. 6 is a table showing contact information for each of the dies in the step of detecting contact failure for each die shown in FIG. 5.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention should not be construed as limited to the embodiments described below, but may be embodied in various other forms. The following examples are provided so that those skilled in the art can fully understand the scope of the present invention, rather than being provided so as to enable the present invention to be fully completed.

In the embodiments of the present invention, when one element is described as being placed on or connected to another element, the element may be disposed or connected directly to the other element, . Alternatively, if one element is described as being placed directly on another element or connected, there can be no other element between them. The terms first, second, third, etc. may be used to describe various items such as various elements, compositions, regions, layers and / or portions, but the items are not limited by these terms .

The terminology used in the embodiments of the present invention is used for the purpose of describing specific embodiments only, and is not intended to be limiting of the present invention. Furthermore, all terms including technical and scientific terms have the same meaning as will be understood by those skilled in the art having ordinary skill in the art, unless otherwise specified. These terms, such as those defined in conventional dictionaries, shall be construed to have meanings consistent with their meanings in the context of the related art and the description of the present invention, and are to be interpreted as being ideally or externally grossly intuitive It will not be interpreted.

Embodiments of the present invention are described with reference to schematic illustrations of ideal embodiments of the present invention. Thus, changes from the shapes of the illustrations, e.g., changes in manufacturing methods and / or tolerances, are those that can be reasonably expected. Accordingly, the embodiments of the present invention should not be construed as being limited to the specific shapes of the regions described in the drawings, but include deviations in the shapes, and the elements described in the drawings are entirely schematic and their shapes Is not intended to describe the exact shape of the elements and is not intended to limit the scope of the invention.

1 is a schematic plan view for explaining a probe holder, FIG. 2 is a schematic plan view for explaining a card holder shown in FIG. 1, and FIG. 3 is a plan view for explaining a die formed on the substrate shown in FIG. Fig.

1 to 3, the probe station 100 performs an electrical inspection using the probe card 20 with respect to the substrate 10 on which the semiconductor elements 11 are formed. The probe station 100 includes an inspection chamber 110 providing a space for performing electrical inspection of the substrate 10, a chuck 120 provided in the inspection chamber 110, a plurality of substrates 10 A transfer module 140 for transferring the substrate 10 and a card holder (not shown) for fixing the probe card 20 in the inspection chamber 10 150).

Specifically, the chuck 120 is disposed in the inspection chamber 110, and the substrate 10 can be seated on the upper surface. Here, the substrate 10 may be a semiconductor wafer, and a plurality of dies 11, which are semiconductor elements, are formed on the upper surface. The die 11 has electrode pads as shown in FIG.

The chuck 120 is configured to be vertically and horizontally movable so that the dies 11 on the substrate 10 are brought into contact with the probes 21 of the probe card 20 . In addition, the chuck 120 may be configured to be rotatable for alignment of the substrate 10.

The transfer module 140 is disposed on one side of the inspection chamber 110. The transfer module 140 may include a transfer robot 142 for transferring the substrate 10. The transfer robot 142 transfers the substrate 10 from the cassette 30 loaded on the load port 130, (10) is taken out and placed on the chuck (120) in the inspection chamber (110).

The card holder 150 may be disposed above the chuck 120. The card holder 150 is coupled to the upper portion of the test chamber 110 and the probe card 20 is detachably coupled to the lower surface of the card holder 150 and disposed in the test chamber 110 . 2, the card holder 150 includes first and second position adjustment driving units 161 and 162 for leveling the probe card 20 with respect to the substrate 10. The first and second position adjustment drivers 161 and 162 adjust the tilting angle and direction of the probe card 20 to adjust the degree of parallelism between the probe card 20 and the substrate 10. Although not shown in detail in the drawings, the first and second position adjusting and driving units 161 and 162 may include a wedge-shaped adjusting block, a ball screw, and a driving motor.

The probe station 100 may be connected to a tester 40 for checking electrical characteristics of the substrate 10. The tester 40 applies electrical signals to the dies 11 for inspection of the substrate 10 through the probe card 20 and transmits the electrical signals to the substrate 11 through the signals output from the dies 11. [ (10) is inspected. At this time, the probes 21 of the probe card 20 are brought into contact with the electrode pads 11a of the dies 11 and electrical signals applied from the tester 40 are applied to the electrode pads 11a .

The probe station 100 is disposed at one side of the chuck 120 and is movable together with the chuck 120. The probe station 100 includes a plurality of probes 21, A camera 170 and an upper alignment camera 180 disposed above the chuck 120 to obtain an image of the patterns on the substrate 10. [ Although not shown in detail in the drawing, the upper alignment camera 180 can be moved in the horizontal direction by a driving unit having a bridge shape. In particular, the lower and upper alignment cameras 170 and 180 may be used for alignment between the substrate 10 and the probe card 20.

Hereinafter, a method of aligning the probe card in the probe station 100 will be described in detail with reference to the drawings.

4 is a flowchart illustrating a method of aligning a probe card according to an embodiment of the present invention.

Referring to FIGS. 1 and 4, a probe card alignment method according to an embodiment of the present invention is as follows.

First, the probe card 20 is placed on the chuck 120 (step S110). At this time, the probe card 20 can be fixed by the card holder 150.

Then, the transfer robot 142 draws the substrate 10 from the cassette 30 and places it on the chuck 120 (step S130). At this time, the substrate 10 is disposed to face the probe card 20.

The probe card aligning method of the present invention is characterized in that after the step S110 of placing the probe card 20 or after the step S130 of placing the substrate 10 on the chuck 120, And 180 may be used to first level the probe card 20 (S120). At this time, the lower camera 180 checks whether the alignment probes for aligning the probe card 20 with the substrate 10 among the probes 21 of the probe card 20 are positioned.

When the substrate 10 is placed on the upper surface of the chuck 120, the probes 21 of the probe card 20 are brought into contact with the substrate 10 to form the dies 11 (see FIG. 3) The probe card 10 is level-based on the contact information output from the probe card 10 (step S140). A detailed description of the step 140 of leveling the probe card 20 based on the contact information will be given later with reference to FIG.

When the leveling of the probe card 20 with respect to the substrate 10 is completed, an inspection signal provided from the tester 40 is transmitted to the die 10 of the substrate 10 through the probes 21 of the probe card 20, The electrical characteristics of the substrate 10 are inspected (step S150).

Hereinafter, the leveling step (S140) of the probe card 20 will be described in detail with reference to the drawings.

FIG. 5 is a flow chart for explaining the leveling step of the probe card shown in FIG. 4, and FIG. 6 is a table showing the contact information for each of the dies in the step of sensing the contact failure for each die shown in FIG. They are examples.

Referring to FIGS. 1, 3, 5, and 6, a leveling step (S140) of the probe card 20 according to an embodiment of the present invention is as follows.

First, the probes 21 of the probe card 20 are brought into contact with the electrode pads 11a of the dies 11 at a predetermined first contact depth (step S141). The contact depth at which the probes 21 press the electrode pads 11a may be adjusted through vertical movement of the probe card 20 or vertical movement of the chuck 120 .

Then, an alignment signal is applied to the electrode pads 11a through the probes 11a (step S142). Here, the alignment signal may be provided to the probe card 20 from the tester 40 as an electrical signal.

Next, the defective contact between the probe and the electrode pad corresponding to each other is detected through the contact information output corresponding to the alignment signal from each of the dies 11 (step S143). That is, when the alignment signal is applied to the electrode pads 11a, each of the dies 11 outputs contact information corresponding to the alignment signal. The contact information may be output from each of the dies 11 as an electrical signal. Accordingly, the contact failure between the probes and the dies can be detected for each die 11 through the contact information.

In one embodiment of the present invention, the contact information may be a current value output from the die 11 corresponding to the alignment signal.

As a result of the detection, it is determined whether there is a die in which a contact failure occurs in the dies 11 formed on the substrate 10 (step S144).

In one embodiment of the present invention, the step (S143) of detecting dies where the contact failure has occurred in the dies (11) It can be determined that a contact failure has occurred in the die outputting the low contact information. Here, the output threshold value is a value output when the probe 21 and the electrode pad 11a normally contact with each other in response to the alignment signal.

In step S144, if there is no die in which the contact failure occurs in the dies 11, the electrical characteristics of the substrate 10 are inspected (step S150).

If there is a die in which a contact failure occurs in the dies 11 in the step S144, on the basis of the positions of the dies where the contact failure occurs, The tilt angle and tilt direction of the card 20 are adjusted (step S147).

The adjustment of the tilt angle and direction of the probe card 20 in step S147 may be performed according to the difference between the contact information value of the die on which the contact failure occurs and the output threshold value Can be determined. The tilt angle and the tilt direction of the probe card 20 can be adjusted by the first and second position adjusting and driving units 161 and 162 (see FIG. 2).

Meanwhile, in the probe card leveling step S140 according to an embodiment of the present invention, in step S144 before the step S147 of adjusting the tilt angle and direction of the probe card 20, If the die is present, the step (S145) may include determining whether any of the dies (11) is in contact with the probe (21) normally.

In step S145, if there is a normally contacted die, step S147 is performed.

In step S145, if the normally contacted die is not present, the probe card may be vertically moved or the chuck 120 may be vertically moved to a second contact depth that is deeper than the first contact depth, 21 is reset (step S146). That is, in the case where there is no die normally contacted among the dies 11, the probes 21 are not sufficiently in contact with the electrode pads 11a due to a low contact depth of the probes 21. [ Accordingly, the contact depth of the probes 21 is increased so that the probes 21 can sufficiently contact the electrode pads 11a.

After the step S146 is performed, the alignment signal may be sequentially applied to the test pads (S142).

In particular, since the probe card alignment method of the present invention applies the alignment signal to all the dies 11 of the substrate 10, it is possible to determine whether or not the output contact information is equal to or greater than the output threshold value, Each of the dies 11 may be compared to determine whether or not a contact failure is detected for each of the dies 11. 6 is a table showing the contact failure of the 64 dies 11 as an example of the case where the substrate 10 has 64 dies 11. In FIG. 6, Device Under Test table shows the dies 11, and OD (Over Drive) shows the contact depth.

In addition, since the probe card alignment method of the present invention detects contact failure using contact information as an electrical signal, it is possible to detect whether the probe 21 has not contacted the die 11, 11, but has not contacted with a sufficient contact depth, and whether the probe 21 has normally contacted the die 11.

That is, FIG. 6 (a) shows an example of outputting contact information lower than the output threshold value for all of the 64 dies. From the 4th die to the 9th die, the 25th die to the 27th die Die 34 and die 34 are dies where the probe 21 outputs the contact information but the probe is not contacted with sufficient depth so that the contact information value output is lower than the output threshold, Are dice whose contact information value is '0' and which are not in contact with the probes. If all of the 64 dies are defective, the contact depth is adjusted by performing step S146.

6 (b) shows an example in which the contact depth is increased as compared with FIG. 6 (a), but some dies output contact information lower than the output threshold value. And die 19, die 37, die 46 to die 49, and die 57 to die 64 are in contact with the probes, but the output contact information value is not in contact with the output threshold value And it can be seen that the contact was not made normally. In this case, step S147 may be performed to adjust the tilt angle and direction of the probe card 20 based on the position of the dies where the contact failure occurs.

FIG. 6 (c) shows an example in which all 64 dies output contact information exceeding the output threshold value, thereby recognizing that all of the 64 dies are normally in contact with the probes 21.

The probe card leveling step S140 according to an embodiment of the present invention may be performed on the substrate 10 first introduced into the chuck 120 after the replacement of the probe card 20. [ Alternatively, the probe card leveling step (S140) of the present invention may be performed on the substrates 10 or alternatively on all the substrates 10. On the other hand, the inspection process using the probe card 20 can be performed on the same lot of substrates 10. For example, the cassette 30 can accommodate 25 substrates 10, and the 25 substrates 10 can constitute one lot.

As described above, the probe card alignment method according to an embodiment of the present invention can level the probe card 20 by detecting defective contact with the probes with respect to each of the dies 11. Therefore, The deviation within the probe 10 can be corrected accurately and the probes 21 can be connected to the dies 11 uniformly. As a result, the probe station 100 can stably perform the electrical inspection of the substrate 10 using the probe card 20, and the inspection reliability can be improved.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the following claims. It can be understood that.

100: probe station 110: inspection chamber
120: Chuck 130: Load port
140: Feed module 150: Card holder
161, 162: Position control driver 170, 180: Alignment camera

Claims (7)

Disposing a probe card having a plurality of probes for inspecting electrical characteristics for a substrate on which a plurality of dies are formed;
Disposing the substrate facing the probe card; And
Wherein the probe card is leveled with respect to the substrate based on contact information, which is an electrical signal output from each die, by bringing the probes into contact with the substrate, And leveling the probe card by detecting each die. The method according to claim 1,
Wherein the leveling of the probe card using the contact information comprises:
Contacting the probes with electrode pads of the dies at a predetermined first contact depth;
Applying an alignment signal to the electrode pads through the probes;
Detecting defective contact between the probe and the electrode pad corresponding to each other through the contact information output from each of the dice corresponding to the alignment signal;
Determining whether any of the dies has a contact failure; And
And adjusting a tilt angle and a direction of the probe card based on a position of the die where the contact failure occurs if the die having the contact defect is present in the step of determining whether the die has the contact defect, How to align probe cards. 3. The method of claim 2,
Wherein the step of leveling the probe card using the contact information comprises: before the step of adjusting the tilt angle and direction of the probe card,
Determining whether there is a die that normally contacts the corresponding one of the dies if it is determined that there is a die where the contact failure occurs, And
Further comprising adjusting the contact depth of the probes to a second contact depth deeper than the first contact depth if the normally contacted die is absent,
Wherein the step of adjusting the contact depth of the probes is performed sequentially from the step of applying the alignment signal to the test pads. 3. The method of claim 2,
The step of determining whether there is a die where the contact failure occurs,
When the output contact information value is lower than an output threshold value that is output when the probe and the electrode pad normally contact each other corresponding to the alignment signal, it is determined that a contact failure occurs in the die that outputs the low contact information value Features a probe card alignment method. 5. The method of claim 4,
Wherein the step of adjusting the tilt angle and direction of the probe card comprises:
Wherein the tilt angle magnitude and direction of the probe card are adjusted according to a difference between the contact information value of the die on which the contact failure occurs and the output threshold value. 3. The method of claim 2,
Wherein the contact information is a current value output from the die corresponding to the alignment signal. The method according to claim 1,
Before the step of leveling the probe card using the contact information,
Further comprising the step of first leveling the probe card by checking the position of probes of the probe card with a camera.

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