CN113687215A - Method and equipment for improving contact precision of probe and wafer test point - Google Patents
Method and equipment for improving contact precision of probe and wafer test point Download PDFInfo
- Publication number
- CN113687215A CN113687215A CN202110893589.2A CN202110893589A CN113687215A CN 113687215 A CN113687215 A CN 113687215A CN 202110893589 A CN202110893589 A CN 202110893589A CN 113687215 A CN113687215 A CN 113687215A
- Authority
- CN
- China
- Prior art keywords
- wafer
- point
- probe
- coordinate system
- identification
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000523 sample Substances 0.000 title claims abstract description 180
- 238000012360 testing method Methods 0.000 title claims abstract description 164
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000004873 anchoring Methods 0.000 claims abstract description 8
- 230000000007 visual effect Effects 0.000 claims description 42
- 239000011159 matrix material Substances 0.000 claims description 17
- 230000009466 transformation Effects 0.000 claims description 16
- 238000010521 absorption reaction Methods 0.000 claims description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 9
- 229910052710 silicon Inorganic materials 0.000 description 9
- 239000010703 silicon Substances 0.000 description 9
- 238000001514 detection method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 239000003550 marker Substances 0.000 description 6
- 238000001179 sorption measurement Methods 0.000 description 6
- 238000004590 computer program Methods 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 2
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 210000004209 hair Anatomy 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/2851—Testing of integrated circuits [IC]
- G01R31/2886—Features relating to contacting the IC under test, e.g. probe heads; chucks
- G01R31/2887—Features relating to contacting the IC under test, e.g. probe heads; chucks involving moving the probe head or the IC under test; docking stations
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/2851—Testing of integrated circuits [IC]
- G01R31/2886—Features relating to contacting the IC under test, e.g. probe heads; chucks
- G01R31/2891—Features relating to contacting the IC under test, e.g. probe heads; chucks related to sensing or controlling of force, position, temperature
Landscapes
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Testing Or Measuring Of Semiconductors Or The Like (AREA)
Abstract
The application relates to a method for improving contact precision of a probe and a wafer test point, which comprises the following steps: anchoring a first identification point in a world coordinate system and establishing a first coordinate system; aligning each test point on the wafer disc with the first identification point one by one, and calculating to obtain a coordinate set [ X ] of each test point on the first coordinate systema,Ya](ii) a Anchoring the second identification point on the wafer disc, and moving the wafer disc to enable the first identification point and the second identification point to be opposite; establishing a second coordinate system based on the position of the second identification point in the world coordinate system; aligning the second identification points with the probe points on the probe card one by one, and calculating to obtain a coordinate set [ X ] of each probe point on a second coordinate systemb,Yb](ii) a Computing a set of coordinates [ X ]a,Ya]And set of coordinates [ X ]b,Yb]And determining the position relation of each probe point and each test point on the X, Y axis. The probe card and the first vision system are always in a fixed state, so that the probe does not have unstable motion precisionAnd the alignment precision of the probe and the test point is improved.
Description
Technical Field
The present disclosure relates to the field of semiconductor testing devices, and more particularly, to a method and a device for improving contact accuracy between a probe and a wafer test point.
Background
The wafer refers to a silicon wafer used for manufacturing a silicon semiconductor integrated circuit, and the original material thereof is silicon. And dissolving the high-purity polycrystalline silicon, doping the dissolved high-purity polycrystalline silicon into silicon crystal seed crystals, and slowly pulling out the silicon crystal seed crystals to form cylindrical monocrystalline silicon. After the silicon crystal bar is ground, polished and sliced, a silicon wafer, namely a wafer, is formed. The silicon wafer is a circular silicon sheet with a thickness of about 1mm (millimeter), and the current domestic wafer production line is mainly 8 inches and 12 inches. After the wafer is manufactured, the wafer test, also called the die sort or the wafer sort, is a very important step. During testing, the electrical performance and circuit functioning of each chip can be detected.
The wafer test is to perform a probe test on each die on a chip, and a probe card is installed on a tester, and the probe card has a plurality of fine probes (probes) made of gold wires, such as hairs, and the die has contact points (pads), which are called test points, and contact points (pads) contacting with the probes (probes) for testing. The electrical characteristics of the die are tested by the contact of the probe and the test point, the unqualified die is marked, and then when the wafer is cut into independent chips by taking the die as a unit, the unqualified die marked with the mark is eliminated by wash one's face, and the next process is not carried out, so that the manufacturing cost is not increased unnecessarily.
The precision control is an important content in the wafer testing process, and in the related technical means, the contact between the probe and the wafer is usually observed in a microscope-assisted observation mode. The specific method comprises the following steps:
s1, observing a wafer by using a microscope arranged above a wafer disc, and acquiring visual field imaging information to be tested on the wafer;
s2, controlling the probe to move into the visual field area by using the probe seat;
s3, using a high-magnification microscope to obtain visual field imaging information of test points in a certain range on the wafer;
s3, controlling the needle heads of the probes to be contacted with all test points on the wafer disc one by using the probe seat so as to carry out detection;
and S4, collecting, processing and storing the detection signals of the probes by using a computer.
Aiming at the technical means, in the process of controlling the needle head of the probe to be contacted with each test point on the wafer disc one by one, a microscope is required to be used for follow-up auxiliary observation all the time, and the contact precision of the probe and the test point is mainly determined by the motion precision of a probe seat. The stroke of the probe seat is limited, and the movement precision of the probe seat to the stroke limit position is easy to be unstable, which can cause the contact precision of the probe and the wafer disc test point to be reduced.
Disclosure of Invention
In order to improve the contact precision of the probe and the wafer disc test point, the application provides a method and equipment for improving the contact precision of the probe and the wafer test point.
In a first aspect, the present application provides a method for improving contact accuracy between a probe and a wafer test point, which adopts the following technical scheme:
a method for improving the contact precision of a probe and a wafer test point comprises the following steps:
s1, anchoring a first identification point in a world coordinate system and establishing a first coordinate system;
s2, moving the wafer disc to enable the test points on the wafer disc to be aligned with the first identification points one by one, and meanwhile obtaining the movement information of the wafer disc in the first coordinate system each time to calculate and obtain a coordinate set [ X ] of each test point in the first coordinate systema,Ya]；
S3, anchoring the second identification point on the wafer disc, moving the wafer disc to enable the first identification point and the second identification point to be in relative position, and returning the wafer disc to the initial height position after alignment is completed;
s4, establishing a second coordinate system based on the position of the second identification point in the world coordinate system;
s5, moving the wafer disc to enable the second identification points to be aligned with the probe points on the probe card one by one, and simultaneously obtaining the moving information of the wafer disc at each time to calculate and obtain a coordinate set [ X ] of each probe point on a second coordinate systemb,Yb]；
S6, calculating coordinatesSet [ X ]a,Ya]And set of coordinates [ X ]b,Yb]To determine the positional relationship of each probe point to each test point on the X, Y axis.
By adopting the technical scheme, the first coordinate system is established according to the first identification point, and the first coordinate system is a fixed absolute coordinate system because the first identification point is anchored at a certain point in the world coordinate system. The wafer disc is moved to enable the test points on the wafer disc to be aligned with the first identification points one by one, the opposite number of the coordinates of each test point in the first coordinate system is obtained by calculating the movement information of the wafer disc in the first coordinate system, and the absolute coordinate set [ X ] of each test point in the first coordinate system is obtained through the opposite number of the coordinates of each test point in the first coordinate systema,Ya]。
Since the second coordinate system is established in the world coordinate system based on the second identification point, the second coordinate system is also a stationary absolute coordinate system. Because the first identification point and the second identification point are aligned, the origin of the first coordinate system and the origin of the second coordinate system are the same in the direction X, Y, and therefore, the absolute coordinate set [ X ] of each test point on the first coordinate systema,Ya]The same as the absolute coordinate set of each test point on the second coordinate system, the error generated during the moving of the wafer disk does not enter the coordinate set [ X ]a,Ya]In (1).
By moving the wafer disc to align the second identification points with the probe points on the probe card one by one, and calculating the movement information of the wafer disc in the second coordinate each time, an absolute coordinate set [ X ] of each probe point in the second coordinate system can be obtainedb,Yb]By calculating a set of coordinates [ X ]a,Ya]And set of coordinates [ X ]b,Yb]The position relation of each probe point and each test point on the X, Y axis can be obtained by the transformation matrix of (2). In the technical scheme, the probe card is always in a fixed state, and the first vision system is also always in a fixed state, so that the situation that the motion precision of the probe is unstable can not occur, and the alignment precision of the probe and the test point is improved. By determining individual probe points and individualThe position relation of the test points on the X, Y axis can control the wafer disc to automatically align with the probe points through a computer program, and the alignment efficiency of the wafer is greatly improved.
Optionally, in step S1, a first vision system is disposed above the wafer tray, where the first vision system has a first vision image obtaining unit, and a center point of the first vision image obtaining unit is located on the first identification point;
in step S2, the height of the wafer disc is changed and the wafer disc is moved to align the test points on the wafer disc with the center point of the first visual image acquisition unit one by one, so that the test points can be clearly imaged in the first visual system, and the movement information of the wafer disc is obtained at the same time, and the movement distance of the wafer disc on the Z axis of the first coordinate system is Δ Z1To calculate the coordinate set [ X ] of each test point on the first coordinate systema,Ya,Za]；
In step S3, the wafer tray is indirectly and fixedly connected to a second vision system, wherein the second vision system has a second vision image acquisition unit, and a center point of the second vision image acquisition unit is located on the second identification point; the first visual system is internally provided with a first identification image, the second visual system is internally provided with a second identification image, the first identification image is aligned with the first identification point, the second identification image is aligned with the second identification point, and the distance between the first visual image acquisition unit and the second visual image acquisition unit is set as H; moving the wafer disc in the direction X, Y of the first coordinate system and changing the height of the wafer disc to enable the first identification image to be clearly imaged in the second vision system, aligning the first identification image and the second identification image, and thereby completing the alignment of the first identification point and the second identification point in the direction X, Y of the first coordinate system, wherein the movement distance of the center point of the second vision image acquisition unit in the direction of the Z axis of the first coordinate system is Δ Z2And returning the wafer disc to the initial height position after the alignment is finished.
In step S5, the wafer disk is moved in the X, Y direction of the second coordinate system and the height of the wafer disk is changed so that the second identification images are aligned one by one with the probe points on the probe card to enable the second identification images to be aligned with the probe points on the probe card one by oneThe probe point can be clearly imaged in the second visual system, and the movement distance of the central point of the second visual image acquisition unit in the Z-axis direction of the first coordinate system is delta Z3And simultaneously obtaining the movement information of the wafer disc at each time to calculate and obtain a coordinate set [ X ] of each probe point on the second coordinate systemb,Yb,Zb]。
By adopting the technical scheme, the distance between the first visual image acquisition unit and the second visual image acquisition unit is set to be H, and the height is the height difference between the first coordinate system and the second coordinate system. By varying the height of the wafer disk by Δ Z1So that the test points on the wafer disk are clearly imaged in the first vision system.
By varying the height of the wafer disk by Δ Z2And aligning the first identification image of the first vision system with the second identification image of the second vision system so that the first identification image can be clearly imaged in the second vision system.
By changing the height of the wafer disc, the probe point can be clearly imaged in the second vision system, and the height variation of the wafer disc based on the first coordinate system is delta Z3. The coordinate set of each probe point on the second coordinate system is [ X ]b,Yb,Zb]The coordinate set of each test point in the first coordinate system is [ X ]a,Ya,Za]The original point of the first coordinate system and the original point of the second coordinate system are the same in the direction X, Y, the height difference value between the first coordinate system and the second coordinate system is H, the mutual position relation between each probe point and each test point in the world coordinate system can be determined by calculating the transformation matrix between each probe point and each test point, and the movement of the wafer disc is controlled by a computer program, so that the test points on the wafer disc automatically contact with the probe points for testing, and the wafer detection efficiency is greatly improved.
Optionally, in step S1, the first vision system scans the test points on the wafer as a whole, and controls the wafer to rotate on a plane parallel to the first coordinate system X, Y, so as to ensure that the array direction of the test points is the same as the X, Y axis direction of the second coordinate system.
By adopting the technical scheme, because the wafer needs to be moved to perform a contact test with the probe card in the test process, the wafer disc needs to be controlled to move in a plane parallel to the first coordinate system X, Y, and the direction of the array of the test points can be ensured to be the same as the X, Y axis direction of the second coordinate system by controlling the wafer to perform plane rotation in a plane parallel to the first coordinate system X, Y, so that the wafer can move along the X or Y axis of the second coordinate system in a single direction in the test process, and does not need to move along the X and Y axes of the second coordinate system in two directions in each movement.
Optionally, in step S3, the first vision system obtains a coordinate set [ X ] of each test point on the first coordinate systema,Ya]Thereafter, the first vision system is moved away from above the wafer disk.
By adopting the technical scheme, the first vision system is moved away from the wafer disc, so that the first vision system does not interfere with other testing steps in the subsequent testing process. Meanwhile, after the first vision system is moved away, the position of the second vision system for observing the probe point is reserved, so that the visual field of the second vision system is not blocked.
Optionally, the method further includes:
s7, controlling the wafer disc to move so that at least one test point on the wafer disc is in point contact with the corresponding probe point, and meanwhile, obtaining the movement information of the wafer disc at the time;
s8. coordinate set [ X ]a,Ya,Za]And set of coordinates [ X ]b,Yb,Zb]The transformation matrix of (2) is a test transformation matrix, and the movement information and the test transformation matrix in the step S7 are used for correction;
and S9, automatically controlling the probe card to carry out full-automatic test on the wafer disc and recording corresponding data information.
By adopting the technical scheme, the test points on the wafer disc are in point contact with the corresponding probe points, the movement information of the wafer disc is recorded, at the moment, the movement path of the wafer disc when the wafer disc moves to the corresponding test points is the actual path coordinate, and the test transformation matrix is corrected through the actual path coordinate to eliminate the height error between the first coordinate system and the second coordinate system, so that the wafer disc can be conveniently and automatically tested by the follow-up automatic control probe card and corresponding data information can be recorded.
In a second aspect, the present application provides an apparatus for improving contact accuracy between a probe and a wafer test point, which adopts the following technical scheme:
the equipment for improving the contact precision of the probe and the wafer test point is used for testing the wafer disc by adopting the method and comprises the following steps:
a frame;
the testing machine is used for carrying out electrical test on the wafer disc, the testing machine is arranged at the top of the rack, and a probe card is arranged at the bottom of the testing machine;
the sample table is used for bearing and fixing the wafer disc, the sample table is provided with a central axis theta, and an image acquisition space is arranged between the sample table and the testing machine;
a stage body driving mechanism for driving the sample stage X, Y, Z to move three axes and to rotate about the central axis θ of the sample stage;
the second vision system is used for acquiring the position information of the probe point of the probe card, is arranged on the sample table and is provided with a second vision image acquisition unit, and a second identification image is arranged on the second vision image acquisition unit;
the first vision system is used for acquiring the position information of the test point of the wafer disc and is provided with a first vision image acquisition unit, a first identification image is arranged on the first vision image acquisition unit, and the first vision system can move into the image acquisition space.
By adopting the technical scheme, the wafer disc is borne on the sample table, and the sample table is controlled by the table body driving mechanism, so that X, Y, Z three-axis movement and rotation around the central axis theta of the sample table are performed, and the wafer disc is conveniently conveyed to the lower part of the testing machine. The first vision system obtains the position [ X ] of each test point on the wafer disc in the first coordinate systema,Ya,Za]The second vision system is used for obtainingPosition of probe point in second vision system [ X ]b,Yb,Zb]The mutual position relation between each probe point and each test point in the world coordinate system can be determined by calculating the transformation matrix between each probe point and each test point, and the movement of the wafer disc is controlled by a computer program, so that the test points on the wafer disc automatically contact with the probe points for testing, and the wafer detection efficiency is greatly improved.
Optionally, the sample stage is provided with a bearing surface for bearing the wafer disc, at least one adsorption groove is formed in one side of the sample stage where the bearing surface is located, and the adsorption groove is communicated with a negative pressure device capable of generating negative pressure.
Through adopting above-mentioned technical scheme, the absorption groove intercommunication has the vacuum device that can produce the negative pressure to make the wafer of placing on the sample bench can be fixed by steadily. Meanwhile, after the wafer disc is detected, the negative pressure can be temporarily closed, so that the wafer can be more conveniently taken down from the sample table and replaced.
Optionally, the first vision system is connected with the rack in a sliding manner, and the moving direction of the first vision system is the same as the moving direction of the Y axis of the sample stage.
By adopting the technical scheme, the first vision system needs to move back and forth in the wafer testing process, and the first vision system is connected with the rack in a sliding mode, so that the first vision system can be conveniently moved back and forth at the working position and the avoiding position.
In summary, the present application includes at least one of the following beneficial technical effects:
1. the probe card is always in a fixed state, and the first vision system is also always in a fixed state, and the coordinate set [ X ] is calculateda,Ya]And set of coordinates [ X ]b,Yb]The position relation of each probe point and each test point on the X, Y axis can be obtained through the transformation matrix, and the alignment precision of the probe and the test point cannot be influenced by the operation error of the probe and the first vision system. By determining the position relationship of each probe point and each test point on the X, Y axis, the method can be used by a computerThe program controls the wafer disc to automatically align with the probe points, so that the alignment efficiency of the wafer is greatly improved;
2. the sample stage carries the wafer disk for X, Y, Z triaxial movement and rotation about the central axis θ of the sample stage to facilitate transport of the wafer disk under the tester for testing. Meanwhile, the first vision system can conveniently acquire images of the test points on the wafer disc, and the second vision system is arranged on the sample table, so that the sample table drives the second vision system to move, and the second vision system can conveniently acquire the images of the test points on the probe card. The first vision system obtains the position [ X ] of each test point on the wafer disc in the first coordinate systema,Ya,Za]The second vision system is used for acquiring the position [ X ] of the probe point in the second vision systemb,Yb,Zb]The mutual position relation between each probe point and each test point in the world coordinate system can be determined by calculating the transformation matrix between each probe point and each test point, and the movement of the wafer disc is controlled by a computer program, so that the test points on the wafer disc automatically contact with the probe points for testing, and the wafer detection efficiency is greatly improved.
Drawings
FIG. 1 is a schematic diagram of an apparatus for improving contact accuracy between a probe and a wafer test point according to an embodiment of the present disclosure;
FIG. 2 is a schematic structural diagram of a sample stage in an embodiment of the present application;
FIG. 3 is a schematic diagram of a relationship between a first vision system and a second vision system during testing of an embodiment of the present application;
FIG. 4 is a schematic diagram of alignment of a test point of a wafer disk with a first vision system in an embodiment of the present application;
FIG. 5 is a schematic diagram of alignment of a first vision system and a second vision system in an embodiment of the present application;
FIG. 6 is a schematic diagram of a second vision system aligned with probe points of a probe card according to an embodiment of the present invention;
fig. 7 is a schematic view showing the contact between the test points of the wafer disk and the probe points of the probe card in the embodiment of the present application.
Description of reference numerals:
1. a frame; 2. a testing machine; 21. a probe card; 22. an image acquisition space; 3. a sample stage; 31. a bearing surface; 32. an adsorption tank; 33. a negative pressure hole; 4. a stage body drive mechanism; 5. a first vision system; 51. a first visual image acquisition unit; 6. a second vision system; 61. a second visual image acquisition unit.
Detailed Description
The present application is described in further detail below with reference to figures 1-6.
The embodiment of the application discloses equipment for improving contact precision of a probe and a wafer test point.
Referring to fig. 1, an apparatus for improving contact accuracy between a probe and a wafer test point includes a rack 1, a testing machine 2, a sample stage 3, a stage driving mechanism 4, a first vision system 5 and a second vision system 6, where the testing machine 2 is installed on an upper surface of the rack 1, a probe card 21 is installed at a bottom of the testing machine 2, the rack 1 has a test cavity, the stage driving mechanism 4 is located at the bottom of the test cavity and is installed on the rack 1, the sample stage 3 is installed on an upper end surface of the stage driving mechanism 4, the second vision system 6 is installed at a side edge of the sample stage 3, the first vision system 5 is installed in the test cavity and is in sliding fit with the rack 1, the second vision system 6 has a second vision image acquiring unit 61, and a second identification image is arranged on the second vision image acquiring unit 61; the first vision system 5 has a first visual image acquisition unit 51, and a first identification image is provided on the first visual image acquisition unit 51. An image acquisition space 22 is provided between the sample stage 3 and the testing machine 2, and the first vision system 5 can move into the image acquisition space 22. In this embodiment, the first and second vision systems 5 and 6 may be wafer micro cameras, the stage driving mechanism 4 may be an X, Y, Z, θ four-axis motion platform, and the stage driving mechanism 4 may drive the sample stage 3 to perform X, Y, Z three-axis motion and to rotate around the central axis θ of the sample stage 3.
Referring to fig. 2, in order to more conveniently remove and replace the wafer from the sample stage 3, the upper surface of the sample stage 3 is provided with a bearing surface 31, one side of the bearing surface 31 of the sample stage 3 is provided with a plurality of adsorption grooves 32, the adsorption grooves 32 are annularly arranged, a blind hole is arranged at the bottom of the adsorption grooves 32, a negative pressure hole 33 communicated with the blind hole is arranged at the side of the sample stage 3, and an air nozzle is arranged on the negative pressure hole 33 and connected with a negative pressure device. The negative pressure device generates negative pressure after the wafer disk is prevented from being on the sample stage 3 and adsorbs the wafer disk on the sample stage 3. After the wafer tray inspection is completed, the negative pressure can be temporarily turned off, so that the wafer can be more conveniently removed from the sample stage 3 and replaced.
The embodiment of the application also discloses a method for improving the contact precision of the probe and the wafer test point.
A method for improving the contact precision of a probe and a wafer test point comprises the following steps:
referring to fig. 3 and 4, the wafer testing apparatus has already completed setting the mechanical coordinate system of the sample stage 3 at the time of factory shipment, the origin of the mechanical coordinate system is set at the front left lower corner of the stage body driving mechanism 4 (where the specific position is unimportant), and the mechanical coordinate system is an absolute coordinate system that is fixed. Anchoring a first identification point in a mechanical coordinate system and establishing a first coordinate system, wherein the first coordinate system is a fixed absolute coordinate system, and calibrating to determine that the coordinate value of the first identification point in the mechanical coordinate system is (X)1,Y1,Z1) (ii) a The first vision system 5 is arranged above the wafer disc, wherein the first vision system 5 is provided with a first vision image acquisition unit 51, and the center point of the first vision image acquisition unit 51 is located on the first identification point. The first vision system 5 scans the test points on the wafer as a whole, controls the wafer to rotate on a plane parallel to the first coordinate system X, Y, and ensures that the array direction of the test points is the same as the direction of the X, Y axis of the second coordinate system, so that the wafer can move along the X axis or the Y axis of the second coordinate system in a single direction in the test process without moving along the X axis and the Y axis of the second coordinate system in a two-way manner every time, on one hand, the precision of the wafer movement can be improved, on the other hand, the running time can be reduced, and the detection efficiency can be improved.
Referring to fig. 3 and 4, the wafer disk is moved to align the test points on the wafer disk with the first identification points one by one, and each time the wafer disk is obtained in the first coordinate systemTo calculate a coordinate set [ X ] of each test point on the first coordinate systema,Ya](ii) a Changing the height of the wafer disc and moving the wafer disc to align the test points on the wafer disc with the central point of the first visual image obtaining unit 51 one by one, so that the test points can be clearly imaged in the first visual system 5, and simultaneously obtaining the moving information of the wafer disc at each time, wherein the moving distance of the wafer disc on the Z axis of the first coordinate system is Δ Z1To calculate the coordinate set [ X ] of each test point on the first coordinate systema,Ya,Za]The coordinate set of each test point in the mechanical coordinate system is [ X ]1+Xa,Y1+Ya,Z1+Za]。
The first vision system 5 obtains a coordinate set [ X ] of each test point on the first coordinate systema,Ya,Za]Thereafter, the first vision system 5 is moved away from above the wafer disk so that the first vision system 5 does not interfere with other testing steps during subsequent testing. At the same time, the first vision system 5 is removed, leaving the second vision system 6 to view the probe points so that the field of view of the second vision system 6 is not obstructed.
Referring to fig. 3 and 5, anchoring a second identification point on the wafer disk, wherein the wafer disk is indirectly and fixedly connected with a second vision system 6, the second vision system 6 has a second vision image obtaining unit 61, and a center point of the second vision image obtaining unit 61 is located on the second identification point; the first visual system 5 is internally provided with a first identification image, the second visual system 6 is internally provided with a second identification image, the first identification image is aligned with the first identification point, the second identification image is aligned with the second identification point, and the distance between the first visual image acquisition unit 51 and the second visual image acquisition unit 61 is set as H; moving the wafer disk in the direction X, Y of the first coordinate system and changing the height of the wafer disk to enable the first marker image to be clearly imaged in the second vision system 6 and aligning the first marker image with the second marker image to complete the alignment of the first marker point with the second marker point in the direction X, Y of the first coordinate system, where the second marker point is at X, Y, and,The moving distances in the Y direction are respectively Delta X and Delta Y, and the moving distance of the central point of the second visual image acquisition unit 61 in the Z-axis direction of the first coordinate system is Delta Z2And returning the wafer disc to the initial height position after the alignment is finished.
Referring to fig. 3 and 5, a second coordinate system is established based on the position of the second identification point in the mechanical coordinate system, and since the second coordinate system is established based on the second identification point in the mechanical coordinate system, the second coordinate system is also a stationary absolute coordinate system. Because the first identification point and the second identification point are aligned, the origin of the first coordinate system and the origin of the second coordinate system are the same in the direction X, Y, and therefore, the absolute coordinate set [ X ] of each test point on the first coordinate systema,Ya,Za]The same as the absolute coordinate set of each test point on the second coordinate system, the error generated during the moving of the wafer disk does not enter the coordinate set [ X ]a,Ya,Za]In (1).
Referring to fig. 3 and 6, the wafer disk is moved and the height of the wafer disk is changed so that the second identification points are aligned with the probe points on the probe card 21 one by one and the probe points can be clearly imaged in the second vision system 6, and the movement distance of the center point of the second vision image acquiring unit 61 in the Z-axis direction of the first coordinate system is Δ Z3And simultaneously obtaining the movement information of the wafer disc at each time to calculate and obtain a coordinate set [ X ] of each probe point on the second coordinate systemb,Yb,Zb]. Assuming that the distance between the test point on the wafer disk and the probe point on the probe card 21 is L, the coordinate set of each probe point in the mechanical coordinate system is [ X ]1+Xb+ΔX,Y1+Yb+ΔY,Z1+Za+L]。
Specifically, referring to fig. 3, knowing that the distance between the first coordinate system and the second coordinate system is H, it can be understood that the distance between the first visual image acquisition unit 51 of the first vision system 5 and the second visual image acquisition unit 61 of the second vision system 6 is H.
In step S5, the focal length of the second vision system 6 is set to a constant f2The second vision system 6 mounted on the side of the sample stage 3 can beThe second visual system 6 moves below the bearing surface 31 of the sample stage 3 to protect the second visual image acquisition unit 61 when the second visual system 6 does not need to work; the second vision system 6 is extended and secured in position when the second vision system 6 is required to operate. When the second vision system 6 works, the distance between the second vision image obtaining unit 61 and the upper surface of the wafer disk is set to be h, and the distance L between the test point on the wafer disk and the probe point on the probe card 21 is obtained as follows:
in step S2, the focal length of the first vision system 5 is set to a constant f1When the distance H between the first coordinate system and the second coordinate system is observed through the first vision system 5, the height of the wafer disk changes is obtained:
in step S3, the distance H between the first coordinate system and the second coordinate system can be obtained by the height of the wafer tray when the first vision system 5 and the second vision system 6 are aligned and imaged:
as can be seen from equations (2) and (3):
the distance h between the second visual image capturing unit 61 and the upper surface of the wafer tray in the formula (5) is substituted into the formula (1) to obtain:
thus, the distance L between the test point on the wafer disk and the probe point on the probe card 21 is obtained.
Coordinate value Z of wafer disc test point on Z axis of first coordinate systema=ΔZ1+f1。
And respectively obtaining the coordinate values of each test point and each probe point in the mechanical coordinate system by calculating the moving distance of the wafer disc each time. By calculating a set of coordinates [ X ]1+Xa,Y1+Ya,Z1+Za]And set of coordinates [ X1+Xb+ΔX,Y1+Yb+ΔY,Z1+Za+L]And the relative position relation of each test point and each probe point in the mechanical coordinate system can be obtained by transforming the matrix. The computer program drives the wafer disc to move by the control platform body driving mechanism 4 according to the relative position relation between each test point and each probe point in the mechanical coordinate system, so that the test points on the wafer disc automatically perform contact test with the probe points, and the wafer detection efficiency is greatly improved.
Referring to fig. 3 and 7, controlling the wafer disc to move so that at least one test point on the wafer disc is in contact with the corresponding probe point, and simultaneously obtaining the movement information of the wafer disc at this time;
set of coordinates [ X ]a,Ya,Za]And set of coordinates [ X ]b,Yb,Zb]The transformation matrix of (2) is a test transformation matrix, and correction is performed using the movement information and the test transformation matrix in step S7. The test points on the wafer disc are in contact with the corresponding probe points, the movement information of the wafer disc is recorded, at the moment, the movement path of the wafer disc when the wafer disc moves to the corresponding test points is an actual path coordinate, the test transformation matrix is corrected through the actual path coordinate, so that the height error between the first coordinate system and the second coordinate system is eliminated, the subsequent automatic control probe card 21 is convenient to carry out full-automatic test on the wafer disc, and the corresponding data information is recorded.
The above are preferred embodiments of the present application, and the scope of protection of the present application is not limited thereby. Wherein like parts are designated by like reference numerals. It should be noted that the terms "front," "back," "left," "right," "upper" and "lower" used in the following description refer to directions in the drawings, and the terms "inner" and "outer" refer to directions toward and away from, respectively, the geometric center of a particular component. Therefore, the method comprises the following steps: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.
Claims (8)
1. A method for improving the contact precision of a probe and a wafer test point is characterized by comprising the following steps:
s1, anchoring a first identification point in a world coordinate system and establishing a first coordinate system;
s2, moving the wafer disc to enable the test points on the wafer disc to be aligned with the first identification points one by one, and meanwhile obtaining the movement information of the wafer disc in the first coordinate system each time to calculate and obtain a coordinate set [ X ] of each test point in the first coordinate systema,Ya]；
S3, anchoring the second identification point on the wafer disc, moving the wafer disc to enable the first identification point and the second identification point to be in relative position, and returning the wafer disc to the initial height position after alignment is completed;
s4, establishing a second coordinate system based on the position of the second identification point in the world coordinate system;
s5, moving the wafer disc to enable the second identification points to be aligned with the probe points on the probe card (21) one by one, and simultaneously obtaining the moving information of the wafer disc at each time to calculate and obtain a coordinate set [ X ] of each probe point on a second coordinate systemb,Yb]；
S6, calculating a coordinate set [ X ]a,Ya]And set of coordinates [ X ]b,Yb]To determine the positional relationship of each probe point to each test point on the X, Y axis.
2. The method of claim 1, wherein the probe is configured to contact the wafer test point with a probe card,
in step S1, a first vision system (5) is disposed above the wafer tray, wherein the first vision system (5) has a first vision image obtaining unit (51), and a center point of the first vision image obtaining unit (51) is located on a first mark point;
in step S2, the height of the wafer disc is changed and the wafer disc is moved to align the test points on the wafer disc with the center point of the first visual image acquisition unit (51) one by one, so that the test points can be clearly imaged in the first visual system (5), and the movement information of the wafer disc at each time is obtained, and the movement distance of the wafer disc on the Z axis of the first coordinate system is Δ Z1To calculate the coordinate set [ X ] of each test point on the first coordinate systema,Ya,Za]；
In step S3, the wafer tray is indirectly and fixedly connected with a second vision system (6), wherein the second vision system (6) has a second vision image obtaining unit (61), and a center point of the second vision image obtaining unit (61) is located on a second identification point; the first visual system (5) is internally provided with a first identification image, the second visual system (6) is internally provided with a second identification image, the first identification image is aligned with the first identification point, and the second identification image is aligned with the second identification point, wherein the distance between the first visual image acquisition unit (51) and the second visual image acquisition unit (61) is set as H; moving the wafer disc in the direction X, Y of the first coordinate system and changing the height of the wafer disc to enable the first identification image to be clearly imaged in the second vision system (6), aligning the first identification image and the second identification image to complete the calibration of the first identification point and the second identification point in the direction X, Y of the first coordinate system, wherein the movement distance of the central point of the second vision image acquisition unit (61) in the direction of the Z axis of the first coordinate system is delta Z2Returning the wafer disc to the initial height position after the alignment is finished;
in step S5, the wafer disk is moved in the direction X, Y of the second coordinate system and the height of the wafer disk is changed so that the second identification images are aligned one by one with the probe points on the probe card (21) so that the probe points can be clearly imaged in the second vision system (6), and the movement distance of the center point of the second vision image acquisition unit (61) in the direction of the Z-axis of the first coordinate system is Δ Z3Simultaneously obtaining the movement information of each time of the wafer disc to calculate and obtain each probeSet of coordinates of point on second coordinate system [ X ]b,Yb,Zb]。
3. The method of claim 2, wherein the probe is configured to contact the wafer test point with a high precision,
in step S1, the first vision system (5) scans the test points on the wafer as a whole, and controls the wafer to rotate on a plane parallel to the first coordinate system X, Y, so as to ensure that the array direction of the test points is the same as the X, Y axis direction of the second coordinate system.
4. The method of claim 3, wherein the probe is configured to contact the wafer test point with a high precision,
in step S3, the first vision system (5) obtains a coordinate set [ X ] of each test point on the first coordinate systema,Ya]Thereafter, the first vision system (5) is removed from above the wafer disk.
5. The method of claim 4, further comprising:
s7, controlling the wafer disc to move so that at least one test point on the wafer disc is in point contact with the corresponding probe point, and meanwhile, obtaining the movement information of the wafer disc at the time;
s8. coordinate set [ X ]a,Ya,Za]And set of coordinates [ X ]b,Yb,Zb]The transformation matrix of (2) is a test transformation matrix, and the movement information and the test transformation matrix in the step S7 are used for correction;
s9, automatically controlling a probe card (21) to carry out full-automatic test on the wafer disc and recording corresponding data information.
6. An apparatus for improving the contact accuracy between a probe and a wafer test point, which is suitable for testing a wafer disc according to the method of any one of claims 1 to 5, wherein the apparatus comprises:
a frame (1);
the testing machine (2) is used for carrying out electrical test on the wafer disc, the testing machine (2) is arranged at the top of the rack (1), and a probe card (21) is arranged at the bottom of the testing machine (2);
a sample stage (3) for carrying and fixing a wafer disk, the sample stage (3) having a central axis θ, an image acquisition space (22) being provided between the sample stage (3) and the testing machine (2);
a stage body driving mechanism (4) for driving the sample stage (3) X, Y, Z to move three-axially and to rotate around a central axis θ of the sample stage (3);
the second vision system (6) is used for acquiring probe point position information of the probe card (21), the second vision system (6) is arranged on the sample table (3), the second vision system (6) is provided with a second vision image acquisition unit (61), and a second identification image is arranged on the second vision image acquisition unit (61);
the first visual system (5) is used for acquiring the position information of the test point of the wafer disc, the first visual system (5) is provided with a first visual image acquisition unit (51), a first identification image is arranged on the first visual image acquisition unit (51), and the first visual system (5) can move into the image acquisition space (22).
7. The apparatus for improving the contact accuracy of the probe and the wafer test point according to claim 6, wherein the sample stage (3) has a carrying surface (31) for carrying the wafer disc, the sample stage (3) is provided with at least one absorption groove (32) at a side where the carrying surface (31) is located, and the absorption groove (32) is communicated with a negative pressure device capable of generating negative pressure.
8. The apparatus for improving the contact accuracy of the probe and the wafer test point according to claim 6, wherein the first vision system (5) is connected with the frame (1) in a sliding manner, and the movement direction of the first vision system (5) is the same as the movement direction of the Y axis of the sample stage (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110893589.2A CN113687215B (en) | 2021-08-04 | 2021-08-04 | Method and equipment for improving contact precision of probe and wafer test point |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110893589.2A CN113687215B (en) | 2021-08-04 | 2021-08-04 | Method and equipment for improving contact precision of probe and wafer test point |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113687215A true CN113687215A (en) | 2021-11-23 |
| CN113687215B CN113687215B (en) | 2024-03-19 |
Family
ID=78578840
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110893589.2A Active CN113687215B (en) | 2021-08-04 | 2021-08-04 | Method and equipment for improving contact precision of probe and wafer test point |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113687215B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114252666A (en) * | 2022-01-17 | 2022-03-29 | 上海华岭集成电路技术股份有限公司 | Method, device, medium and electronic equipment for obtaining position distribution of test needles on probe card |
| CN115728233A (en) * | 2022-09-14 | 2023-03-03 | 深圳市智佳能自动化有限公司 | Wafer detection platform and method thereof |
| CN117012689A (en) * | 2023-09-26 | 2023-11-07 | 天津中科晶禾电子科技有限责任公司 | Wafer alignment device and method |
| CN117472126A (en) * | 2023-12-27 | 2024-01-30 | 深圳市森美协尔科技有限公司 | Chuck cleaning method and related device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090195263A1 (en) * | 2008-01-31 | 2009-08-06 | Tokyo Electron Limited | Probe apparatus, probing method and storage medium |
| CN105513990A (en) * | 2015-12-07 | 2016-04-20 | 杭州长川科技股份有限公司 | Probe station image positioning device and vision alignment method |
| US20170276701A1 (en) * | 2016-03-23 | 2017-09-28 | Global Unichip Corporation | Method, system for utilizing a probe card, and the probe card |
| CN110927549A (en) * | 2019-11-21 | 2020-03-27 | 广西天微电子有限公司 | Wafer repositioning method and system |
| CN111386595A (en) * | 2017-12-01 | 2020-07-07 | 东京毅力科创株式会社 | Method for adjusting position of probe tip and inspection device |
| CN212255574U (en) * | 2020-04-30 | 2020-12-29 | 迈柯博科技(上海)有限公司 | Wafer test equipment |
-
2021
- 2021-08-04 CN CN202110893589.2A patent/CN113687215B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090195263A1 (en) * | 2008-01-31 | 2009-08-06 | Tokyo Electron Limited | Probe apparatus, probing method and storage medium |
| CN105513990A (en) * | 2015-12-07 | 2016-04-20 | 杭州长川科技股份有限公司 | Probe station image positioning device and vision alignment method |
| US20170276701A1 (en) * | 2016-03-23 | 2017-09-28 | Global Unichip Corporation | Method, system for utilizing a probe card, and the probe card |
| CN111386595A (en) * | 2017-12-01 | 2020-07-07 | 东京毅力科创株式会社 | Method for adjusting position of probe tip and inspection device |
| CN110927549A (en) * | 2019-11-21 | 2020-03-27 | 广西天微电子有限公司 | Wafer repositioning method and system |
| CN212255574U (en) * | 2020-04-30 | 2020-12-29 | 迈柯博科技(上海)有限公司 | Wafer test equipment |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114252666A (en) * | 2022-01-17 | 2022-03-29 | 上海华岭集成电路技术股份有限公司 | Method, device, medium and electronic equipment for obtaining position distribution of test needles on probe card |
| CN115728233A (en) * | 2022-09-14 | 2023-03-03 | 深圳市智佳能自动化有限公司 | Wafer detection platform and method thereof |
| CN115728233B (en) * | 2022-09-14 | 2023-08-29 | 深圳市智佳能自动化有限公司 | Wafer detection platform and method thereof |
| CN117012689A (en) * | 2023-09-26 | 2023-11-07 | 天津中科晶禾电子科技有限责任公司 | Wafer alignment device and method |
| CN117012689B (en) * | 2023-09-26 | 2023-12-15 | 天津中科晶禾电子科技有限责任公司 | Wafer alignment device and method |
| CN117472126A (en) * | 2023-12-27 | 2024-01-30 | 深圳市森美协尔科技有限公司 | Chuck cleaning method and related device |
| CN117472126B (en) * | 2023-12-27 | 2024-03-19 | 深圳市森美协尔科技有限公司 | Chuck cleaning method and related device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113687215B (en) | 2024-03-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113687215B (en) | Method and equipment for improving contact precision of probe and wafer test point | |
| US4677474A (en) | Wafer prober | |
| US4786867A (en) | Wafer prober | |
| EP0675366B1 (en) | Probe system and probe method | |
| JP2963603B2 (en) | Probe device alignment method | |
| US5539676A (en) | Method of identifying probe position and probing method in prober | |
| US4755747A (en) | Wafer prober and a probe card to be used therewith | |
| US7772862B2 (en) | Alignment method, tip position detecting device and probe apparatus | |
| US5410259A (en) | Probing device setting a probe card parallel | |
| KR100248569B1 (en) | Probe system | |
| US20070134904A1 (en) | High precision die bonding apparatus | |
| US11152230B2 (en) | Device and method for bonding alignment | |
| JP2007139704A (en) | Regulator for reference height position of nozzle tip, and sampler | |
| KR101020396B1 (en) | Probe apparatus and probing method | |
| CN113589134A (en) | Wafer testing apparatus and method | |
| CN212255574U (en) | Wafer test equipment | |
| KR20140022582A (en) | Flip chip bonding apparatus and calibration method thereof | |
| JP4033468B2 (en) | Nozzle tip position measuring device and spotting device using the same | |
| CN116953590B (en) | Omnibearing probe measuring device and method | |
| JPH07297241A (en) | Probe method | |
| TW201910793A (en) | Probe station | |
| JP4264404B2 (en) | Bonding equipment | |
| JP2003152037A (en) | Method and apparatus for inspecting wafer as well as inspecting infrared imaging unit | |
| JP2501613B2 (en) | Wafer prober | |
| KR100262901B1 (en) | Method of identifying probe position and probing method in prober |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |