CN111208400B

CN111208400B - Wafer test equipment and test method

Info

Publication number: CN111208400B
Application number: CN201811372448.0A
Authority: CN
Inventors: 刘旭峰
Original assignee: Hangzhou Hikmicro Sensing Technology Co Ltd
Current assignee: Hangzhou Hikmicro Sensing Technology Co Ltd
Priority date: 2018-11-16
Filing date: 2018-11-16
Publication date: 2022-11-01
Anticipated expiration: 2038-11-16
Also published as: CN111208400A

Abstract

The embodiment of the invention discloses a wafer test device and a test method, relates to the technical field of silicon wafer test, and can provide a vacuum test environment so as to meet the occasion with vacuum test requirements on wafers. The method comprises the following steps: the vacuum system comprises a box body and a vacuumizing module connected to the box body, and the test board is arranged in the box body; the vacuumizing module comprises a vacuum pump, and the test board comprises a carrying platform for placing a wafer and a probe for testing the wafer. The invention is suitable for testing the performance of semiconductors, photoelectric components, integrated circuits and the like, and is particularly suitable for testing wafers.

Description

Wafer test equipment and test method

Technical Field

The invention relates to the technical field of silicon wafer testing, in particular to wafer testing equipment and a wafer testing method.

Background

At present, a Probe station (Probe station) is used as a main device for testing wafer performance, and generally a vacuum adsorption wafer fixing mode is adopted to test a wafer in a standard atmospheric pressure environment, and in an occasion with a vacuum test requirement on the wafer, the existing Probe station cannot provide a vacuum environment required by the test, so that the test environment requirement of the wafer under the vacuum condition cannot be met.

Disclosure of Invention

In view of this, embodiments of the present invention provide a wafer testing apparatus and a testing method, which can provide a vacuum testing environment, so as to meet the situation of vacuum testing requirements on a wafer.

In order to achieve the purpose, the embodiment of the invention adopts the following technical scheme:

in a first aspect, the testing equipment provided by the embodiment of the invention comprises a vacuum system and a testing platform, wherein the vacuum system comprises a box body and a vacuumizing module connected to the box body, and the testing platform is arranged in the box body; the vacuumizing module comprises a vacuum pump, and the test board comprises a carrying platform for placing a wafer and a probe for testing the wafer.

Optionally, the test platform is slidably disposed on the inner bottom surface of the box body.

Optionally, the test board includes a fixed seat, a sliding block is arranged at the bottom of the fixed seat, a sliding rail matched with the sliding block is arranged on the bottom surface of the box body, and the test board can slide on the sliding rail through the sliding block.

Optionally, the test station further comprises a first locking mechanism for locking the test station.

Optionally, the test bench further comprises: the first adjusting mechanism is used for adjusting the position of the carrying platform in the Y-axis direction, and the second adjusting mechanism is used for adjusting the position of the carrying platform in the X-axis direction; the X-axis direction and the Y-axis direction are parallel to the bottom surface of the box body;

the first adjusting mechanism is arranged on the fixing seat, the second adjusting mechanism is arranged on the first adjusting mechanism, and the carrying platform is arranged on the second adjusting mechanism.

Optionally, the test bench further comprises: the first adjusting mechanism is used for adjusting the position of the carrier in the Y-axis direction, and the second adjusting mechanism is used for adjusting the position of the carrier in the X-axis direction;

the test bench further comprises: a third adjusting mechanism for adjusting the position of the carrier in the X-axis direction, a fourth adjusting mechanism for adjusting the position of the carrier in the Y-axis direction, a fifth adjusting mechanism for adjusting the position of the carrier in the Z-axis direction, and a sixth adjusting mechanism for adjusting the horizontal rotation angle of the carrier;

the X-axis direction and the Y-axis direction are parallel to the bottom surface of the box body, and the Z-axis direction is perpendicular to the bottom surface of the box body;

the first adjusting mechanism is arranged on the fixing seat, the second adjusting mechanism is arranged on the first adjusting mechanism, the third adjusting mechanism, the fourth adjusting mechanism, the fifth adjusting mechanism and the sixth adjusting mechanism are arranged on the second adjusting mechanism, wherein the fourth adjusting mechanism is close to the second adjusting mechanism relative to the third adjusting mechanism, the fifth adjusting mechanism is positioned above the fourth adjusting mechanism, the sixth adjusting mechanism is positioned above the fifth adjusting mechanism, and the carrying platform is positioned on the sixth adjusting mechanism.

Optionally, a first sliding block is arranged at the bottom of the first adjusting mechanism, a first sliding rail matched with the first sliding block is arranged on the upper surface of the fixed seat, and the first adjusting mechanism slides on the first sliding rail through the first sliding block;

a second sliding rail is arranged on the upper surface of the first adjusting mechanism, a second sliding block matched with the second sliding rail is arranged at the bottom of the second adjusting mechanism, and the second adjusting mechanism slides on the second sliding rail through the second sliding block;

the first adjusting mechanism and the second adjusting mechanism are coarse adjusting mechanisms.

Optionally, a sliding platform and a micrometer head arranged on the sliding platform are respectively mounted on the third, fourth, fifth and sixth adjusting mechanisms, and the sliding platform is driven to slide by the micrometer head so as to finely adjust the position of the carrying platform on the X, Y and Z axes and the rotation angle of the carrying platform in the horizontal direction.

Optionally, the first adjusting mechanism and the second adjusting mechanism are respectively provided with a second locking mechanism.

Optionally, a limit locking member for limiting the moving position of the carrier in the Z-axis direction is arranged in the circumferential direction of the micrometer head on the fifth adjusting mechanism.

Optionally, the sixth adjusting mechanism includes a platform, the stage is mounted on the platform, and a pressing ring for fixing the wafer is disposed on the stage.

Optionally, a needle clip mounting mechanism is further arranged on the test board, the probe mounting mechanism comprises a supporting plate, a needle clip fixing seat and a needle clip pressing block, the supporting plate is vertically arranged on the fixing seat, the needle clip fixing seat is mounted on the supporting plate and located above the loading platform, a needle clip mounting groove is formed in the needle clip fixing seat, and the needle clip pressing block is used for fixing a needle clip in the needle clip mounting groove.

Optionally, a plurality of probes are installed in the pincard.

Optionally, a transparent window is arranged at the top end of the box body, and a microscope is arranged above the transparent window.

Optionally, a vacuum release valve is further arranged on the box body.

In a second aspect, an embodiment of the present invention provides a wafer testing method, which is used in any one of the testing apparatuses in the first aspect, and includes:

opening a box door of the vacuum system;

fixedly mounting the wafer on a test board and pushing the wafer into the box body;

closing the box body door, and opening a vacuumizing module to vacuumize the box body;

and when the vacuum degree in the box body reaches a preset vacuum degree, testing the unit to be tested of the wafer by using a probe installed on the test board.

The embodiment of the invention discloses wafer test equipment and a test method, which comprise a vacuum system and a test board, wherein the vacuum system comprises a box body and a vacuumizing module connected to the box body, and the test board is arranged in the box body; the test bench comprises a carrying platform for placing the wafer and a probe for testing the wafer. Through setting up vacuum system, set up the testboard in vacuum system's box, when needs carry out the vacuum test to the wafer, open the evacuation module, to the evacuation in the box, just can provide the vacuum test environment for the wafer test to can satisfy the occasion that has the vacuum test requirement to the wafer.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a front view of a wafer test apparatus according to an embodiment of the present invention;

FIG. 2 is a top view of a wafer test apparatus according to an embodiment of the present invention;

FIG. 3 is a front view of one embodiment of the test station of FIG. 1;

FIG. 4 is an exploded view of one embodiment of the test station of FIG. 1;

FIG. 5 is a schematic diagram of an embodiment of the coarse adjustment mechanism shown in FIG. 4;

FIG. 6 is a schematic structural diagram of an embodiment of the fine adjustment mechanism shown in FIG. 4;

FIG. 7 is a schematic structural view of one embodiment of the wafer mounting method of FIG. 1;

FIG. 8 is a flowchart illustrating an embodiment of a wafer testing method according to the present invention.

Detailed Description

A test apparatus according to an embodiment of the present invention is described in detail below with reference to the accompanying drawings.

It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

Referring to fig. 1 to 4, an embodiment of the invention provides a wafer testing apparatus, which is mainly applied to performance testing of semiconductors, optoelectronic devices, integrated circuits, and the like, and is particularly used for testing wafers (wafers); the wafer is a silicon wafer used for manufacturing a silicon semiconductor integrated circuit, and is called a wafer because the wafer is circular in shape. The wafer test equipment comprises a vacuum system 1 and a test board 2, wherein the vacuum system 1 comprises a box body 11 and a vacuumizing module 12 connected to the box body 11, and the test board 2 is arranged in the box body 11; the test station includes a stage 21 for placing a wafer and a probe 22 for testing the wafer.

It will be appreciated that the housing and evacuation module cooperate to provide the vacuum environment required for testing. In order to clearly show the schematic structure of the test stations inside the cabinet, the front door of the cabinet is transparently treated in fig. 1. Certainly, the front door of the box body can also be designed into a transparent body during design, so that an operator can observe the test process condition from the outside, and the abnormal condition can be timely treated. Of course, the transparent substrate can be designed as an opaque body, which is not limited in this embodiment.

In addition, in this embodiment, specifically, the vacuum pumping module includes a vacuum pump, and the vacuum pump is connected to the box body and is used for pumping vacuum inside the box body; it should be understood that fig. 1 is a schematic diagram, and does not show all structures, and should not be construed as limiting the implementation of the solution according to the embodiment of the present invention. For example, the evacuation module in fig. 1 only shows its interface location on the vacuum cabinet, and in particular implementations, it is conceivable that: the back of the interface can also be connected with a vacuum pump to vacuumize the vacuum box body.

It is understood that the carrier is positioned corresponding to the position of the probe, so that the probe can test the wafer. The corresponding arrangement may be understood as that after the position point of one object is fixed, another object corresponds to the former object in the spatial position relation, for example, the probe is correspondingly arranged above the carrier.

The embodiment of the invention discloses wafer test equipment which comprises a vacuum system and a test board, wherein the vacuum system comprises a box body and a vacuumizing module connected to the box body, and the test board is arranged in the box body; the test bench comprises a carrying platform for placing the wafer and a probe for testing the wafer. Through setting up vacuum system, set up the testboard in vacuum system's box, when needs carry out the vacuum test to the wafer, open the evacuation module, to the evacuation in the box, just can provide the vacuum test environment for the wafer test to can satisfy the occasion that has the vacuum test requirement to the wafer.

In this embodiment, as an optional embodiment, the test board 2 is slidably disposed on the inner bottom surface of the box body.

It can be understood that, through with the testboard slidable set up in on the bottom surface in the box, after a wafer test is accomplished, when changing next wafer, through with the testboard is followed the box and is pulled out, then changes the wafer in comparatively uncovered exterior space, and is convenient for the easy operation of changing the wafer in the box is inside.

Specifically, referring to fig. 1 and 4, the test board can slide relative to the inner bottom surface of the case body in a structure that the test board includes a fixed seat 23, a sliding block 231 is disposed at the bottom of the fixed seat 23, a sliding rail 111 matched with the sliding block is disposed on the inner bottom surface of the case body 11, and the test board can slide on the sliding rail through the sliding block 231. Or, the bottom of the fixed seat is provided with a slide rail, and a slide block matched with the slide rail is arranged on the bottom surface in the box body. Other structures which cooperate to achieve mutually guided linear sliding are also possible. When the sliding rail is specifically implemented, the sliding block and the sliding rail can also be integrated finished products, a mounting hole is formed in the fixing seat, a threaded hole is formed in the sliding block, the sliding block is fixed on the fixing seat through threaded connecting pieces such as bolts, the sliding rail is provided with the threaded connecting pieces, a threaded hole is formed in the inner bottom surface of the box body, and the sliding rail is locked and fixed on the inner bottom surface of the box body.

It will be appreciated that since the test stations are slidable within the housing, as an alternative embodiment, a first locking mechanism 24 is provided for locking the test stations in order to prevent the test stations from shifting in position during testing, which may be caused by sudden vibrations.

In this embodiment, referring to fig. 1 or fig. 3, the first locking mechanism 24 may be a first baffle 241 disposed on the fixed seat of the test platform and located at the front door end, a screw 242 is disposed on the first baffle 241, a locking block corresponding to the baffle is disposed on the bottom surface of the box body, a threaded hole matched with the screw is disposed on the locking block, and a threaded hole is also disposed on the fixed seat of the test platform, when the test platform needs to be pulled out, the screw 242 is rotated counterclockwise, the screw is disengaged from the threaded hole, and the test platform is in a movable state, so that the test platform can be pulled out from the box body. When the test board is pushed into the box body, the screw can be screwed into the threaded hole by rotating the screw clockwise, so that the test board 2 is locked in the box body.

Therefore, through the arrangement of the first locking mechanism 24, after the wafer is replaced, the test board is pushed into the box body, and then the test board is locked by the first locking mechanism 24, so that the test board is prevented from accidentally sliding to influence normal test.

With continued reference to fig. 3 and 4, as an alternative embodiment, the testing station 2 further includes: a first adjustment mechanism 25 that adjusts the position of the stage in the Y-axis direction, and a second adjustment mechanism 26 that adjusts the position of the stage in the X-axis direction; the X-axis direction and the Y-axis direction are parallel to the bottom surface of the box body;

the first adjusting mechanism 25 is disposed on the fixing base 23, the second adjusting machine 26 is disposed on the first adjusting mechanism 25, and the carrier is disposed on the second adjusting mechanism.

It is understood that the X-axis and the Y-axis are relative to each other, and they may be switched according to the actual application. The specific configurations of the first adjustment mechanism and the second adjustment mechanism are not limited in this embodiment, and any mechanism may be used as long as the function of adjusting the position of the stage in the X-axis direction and the Y-axis direction is achieved. The carrier can be directly arranged on the second adjusting mechanism, specifically, a first mounting hole can be arranged on the carrier, a corresponding second mounting hole can also be arranged on the second adjusting mechanism, and the carrier is locked and fixed on the second adjusting mechanism by a fastener through the mounting hole. Of course, the second adjustment mechanism may be indirectly provided.

In this embodiment, by setting the first adjusting mechanism and the second adjusting mechanism, the position of the carrier in two directions can be adjusted.

As an alternative embodiment, the first adjusting mechanism and the second adjusting mechanism are coarse adjusting mechanisms for coarse adjusting the positions of the carrier on the X axis and the Y axis.

Referring to fig. 3 to 5, as a first adjusting mechanism for roughly adjusting the Y-axis position, in order to reduce the production cost, a specific structure of the first adjusting mechanism may include a first platform 251, a first slider 252 is disposed at the bottom of the platform, a first slide rail 231 engaged with the first slider is disposed on the upper surface of the fixed base 23, and the first adjusting mechanism slides on the first slide rail through the first slider, so as to achieve rough adjustment of the carrier in the Y-axis direction.

Similarly, in this embodiment, in specific implementation, the sliding block and the sliding rail may also be an integrated finished product, a mounting hole is formed in the first platform, a threaded hole is formed in the sliding block, the sliding block is fixed to the first platform by a threaded connector such as a bolt, the sliding rail is provided with a threaded connector, and a threaded hole is formed in the upper surface of the fixing base to lock and fix the sliding rail to the fixing base.

With continued reference to fig. 3 to fig. 5, the second adjusting mechanism may be a linear guide structure, and may be disposed on the basis of the first platform 251, specifically, the second adjusting mechanism may also include: and a second platform 261, wherein a second slide rail 262 is arranged on the upper surface of the first platform 251, a second slider matched with the second slide rail is arranged at the bottom of the second platform 261, and the second adjusting mechanism slides on the second slide rail 262 through the second slider, so as to realize coarse adjustment of the position of the carrier in the X-axis direction.

In order to increase the adjustment range of the position in the wafer test, the test range of the wafer specification type is expanded. Referring to fig. 3, fig. 4, and fig. 6, in this embodiment, as an optional embodiment, a specific adjustment scheme for implementing combination of coarse adjustment and fine adjustment on a test bench is further provided, and a specific implementation scheme may be that the test bench further includes: a first adjustment mechanism 25 that adjusts the position of the stage in the Y-axis direction, a second adjustment mechanism 26 that adjusts the position of the stage in the X-axis direction, a third adjustment mechanism 27 that adjusts the position of the stage in the X-axis direction, a fourth adjustment mechanism 28 that adjusts the position of the stage in the Y-axis direction, a fifth adjustment mechanism 29 that adjusts the position of the stage in the Z-axis direction, and a sixth adjustment mechanism 30 that adjusts the horizontal rotation angle of the stage.

The X-axis direction and the Y-axis direction are parallel to the bottom surface of the box body, and the Z-axis direction is perpendicular to the bottom surface of the box body.

In the present embodiment, the X axis and the Y axis are also opposed to each other, and in actual use, the two axes may be switched depending on the case. The specific structure of the first adjusting mechanism and the second adjusting mechanism, the third adjusting mechanism and the fourth adjusting mechanism, and the fifth adjusting mechanism and the sixth adjusting mechanism is not limited in this embodiment, as long as the functions of coarse adjustment and fine adjustment of the position of the carrier in the X-axis direction and the Y-axis direction and fine adjustment of the angle of the carrier in the Z-axis direction and the horizontal rotation direction can be achieved.

In the embodiment, the position of the carrier is adjusted by adopting an adjusting mode combining rough adjustment and fine adjustment, so that the adjusting range of the position in the wafer test is increased, and the testing range of the specification and the type of the wafer is expanded.

In this embodiment, as an optional embodiment, the third, fourth, and fifth adjusting mechanisms may also be provided with an adjusting stroke limiting mechanism to limit the adjusting amplitude.

Referring to fig. 4, the carrier may be provided with mounting holes, and the sixth adjusting mechanism may be provided with corresponding mounting holes, and the carrier is locked and fixed on the sixth adjusting mechanism by fasteners.

As shown in fig. 3, fig. 4, and fig. 6, as a specific embodiment, a sliding platform and a micrometer head disposed on the sliding platform are respectively mounted on the third, fourth, fifth, and sixth adjusting mechanisms, and the micrometer head drives the sliding platform to slide, so as to finely adjust the position of the stage on the X, Y, and Z axes and the rotation angle of the stage in the horizontal direction.

The micrometer head is a measuring main body part of a micrometer (also called a micrometer), and comprises a micrometer screw, a locking device, a force measuring device and a micro-cylinder, and the position connection or the matching relationship of the structure is the prior art, so that the description is omitted. The third, fourth, fifth and sixth adjusting mechanisms are precision sliding tables, and the precision sliding tables are sliding platforms which are driven by micrometer heads and can manually perform fine displacement adjustment. The third and fourth adjusting mechanisms may employ an integrated type precision sliding table with adjustable X and Y directions, for example, an X/Y precision sliding table manufactured by spay drive element (shanghai) limited and having a model of LAM-1252W, the fifth adjusting mechanism may employ a precision sliding table with adjustable Z-axis position, for example, a precision sliding table manufactured by spay drive element (shanghai) limited and having a model of LAM-1003W, and the sixth adjusting mechanism may employ a precision sliding table rotating around an axis, for example, a precision rotary sliding table manufactured by spay drive element (shanghai) limited and having a model of TAM-1006W. The position adjusting precision of the above exemplary product can reach 0.01mm. It should be noted that the above-mentioned examples are only for the purpose of fully disclosing the embodiments of the present invention, and are not to be construed as exclusive limitations on other implementable schemes.

Specifically, referring to fig. 3, 4 and 6, the third adjusting mechanism 27 includes a third platform 271, the third platform is provided with a first micrometer head 272, the fourth adjusting mechanism 28 includes a fourth platform 281, the fourth platform is provided with a second micrometer head 282, the fifth adjusting mechanism 29 includes a fifth platform 291, the fifth platform is provided with a third micrometer head 292, the sixth adjusting mechanism 30 includes a sixth platform 301, and the sixth platform is provided with a fourth micrometer head 302;

the fourth platform is located on the third platform, the fifth platform is located on the fourth platform, and the sixth platform is located on the fifth platform.

It will be appreciated that a transmission mechanism is also provided inside each platform, which cooperates with the micrometer screw of the micrometer head to achieve positional sliding, although the transmission mechanism inside the particular platform is not shown in the figures, it is conceivable that the transmission mechanism may be a gear transmission mechanism, a screw transmission mechanism, etc. The micrometer head is used as a driving part for adjusting the carrier in the corresponding direction, and the precision of the micrometer head can be adjusted to the thousand decimals of millimeters, so that the micrometer head is used as the driving part and is creatively used for adjusting the position of the carrier, the precision adjustment of the position of the carrier can be realized, and the alignment degree of the installation position of the wafer and the probe can be improved.

It will be appreciated that in order to lock the adjusted position, as an alternative embodiment, as shown in fig. 3, the first adjustment mechanism is provided with a second locking mechanism 253, and the second adjustment mechanism is provided with a second locking mechanism 263.

As an alternative embodiment, the second locking mechanism 253 (or 263) is a rail clamp.

It can be understood that when the guide rail clamp is locked, the coarse adjustment mechanism can be locked on the guide rail only by rotating, and the guide rail clamp is simple in structure and convenient to operate. In addition, each fine adjustment mechanism can lock the position through the self-locking function of the micrometer head.

It can be understood that, by arranging the locking mechanism, the phenomenon that the tested unit Pad is separated from the probe due to the position change can be avoided in the test process, so that the accuracy and reliability of test data can be ensured.

Referring to fig. 3, 4 and 6, in the circumferential direction of the micrometer head of the fifth adjusting mechanism, there is a limit lock 293 for limiting the moving position of the carrier in the Z-axis direction,

specifically, the limiting locking part can be a locking ring and is arranged on the circumference of a micrometer screw of the micrometer head, and the stroke of the micrometer screw of the micrometer head can be limited, so that the height position of the carrier on the Z axis can be limited, and the phenomenon that the probe is damaged due to overlarge deformation caused by the fact that the carrier moves in the Z axis direction and displaces overlarge to exert an acting force on the probe is avoided.

Referring to fig. 4 and 8, in this embodiment, as an optional embodiment, a pin card mounting mechanism is further disposed on the test platform, the pin card mounting mechanism includes a supporting plate 31, a pin card fixing seat 32, and a pin card pressing block 33, the supporting plate 31 is vertically disposed on the fixing seat 23, the pin card fixing seat 32 is mounted on the supporting plate 31 and is located above the carrier 21, a pin card mounting groove 34 is disposed on the pin card fixing seat 32, and the pin card pressing block 33 is used for fixing a pin card 35 in the pin card mounting groove 34.

It will be appreciated that the probe is provided in the pin card. The probe card refers to a probe card, belongs to a test interface, and mainly utilizes a probe on the probe card to directly contact with a Pad point on a chip so as to test parameters of a bare chip.

Referring to fig. 1 or 3, as a preferred embodiment, a plurality of probes are provided in the needle card.

It can be understood that, when the wafer is tested by the existing test probe station, the mode of probe movement, wafer fixation and single-point test is adopted, and the test efficiency is low because one unit to be tested of the wafer needs to be pricked for multiple times.

In this embodiment, by using the above structure, a test mode in which the probe is fixed and the wafer moves along with the stage is adopted, so that multi-point simultaneous testing of multiple probes is realized. Specifically, a plurality of probes are adopted to contact one unit to be tested on the 8' wafer at a time, the test data of the unit to be tested can be read at one time, the phenomenon that the same unit to be tested is pricked by moving the probes for multiple times is avoided, and the test efficiency is improved.

It is understood that there are multiple pads (joints) on the unit to be tested, and the Pad may be translated as a joint or a welding pressure point, which refers to a point or a block on the wafer for the unit to be tested to contact and connect with the probe.

It can be understood that the existing way of testing the wafer under the standard atmospheric pressure generally adopts vacuum adsorption to fix the wafer, and the principle is to use vacuum negative pressure to "adsorb" the workpiece so as to achieve the purpose of clamping the workpiece. When the vacuum chuck works, a pressure vacuum state is formed inside the chuck and is lower than the external atmospheric pressure, a workpiece, such as a wafer, is adsorbed and fixed under the action of the external pressure, and the higher the vacuum degree inside the chuck is, the tighter the adsorption and fixation between the workpiece and the chuck is. However, in this way, when the wafer is in the vacuum test environment, the inside of the chuck and the outside environment are both in a vacuum state, which may cause the wafer to be fixed in a failure.

In order to solve the problem that the conventional method of fixing a wafer by vacuum suction is not suitable for a vacuum test environment, referring to fig. 3 and 4, in this embodiment, as an optional embodiment, the sixth adjusting mechanism includes a sixth platform 301, the platform is provided with the stage 21, and the stage 21 is provided with a pressing ring 211 for fixing a wafer.

It can be understood that the embodiment of the invention not only provides a vacuum environment required by the wafer test, but also provides a wafer fixing mode suitable for the vacuum test environment, the wafer is fixed by adopting a pressure ring fixing and locking mode, the wafer is not influenced by an external pressure environment, and the wafer fixing mode can be suitable for fixing the wafer in the vacuum test environment.

Referring to fig. 7, in this embodiment, as an alternative embodiment, the pressing ring 211 includes an arc body 212, and a concave portion 2121 for clamping an edge of a wafer is disposed on a lower edge of an inner side of the arc body.

When the wafer clamping device is used specifically, two or more clamping rings can be arranged as required, the clamping rings are uniformly distributed and pressed on the edge of a wafer, and then the clamping rings are locked and fixed on the carrying platform by using the fastening pieces. The pressing ring can also be a circular ring body.

In addition, in this embodiment, it can be understood that, generally, during the design of a probe card, the arrangement direction of the test probes is determined to be the X direction or the Y direction, and when the test probes are installed on the wafer test probe station, the test probes need to be installed according to the arrangement direction of the probes, that is, the test probe direction is fixed. Pad points (the Pad may be translated into a contact point or a welding pressure point, and refers to a point or a block on the wafer for the contact connection between the unit to be tested and the probe) on the wafer W are usually arranged in an array, and when manufacturing the Pad points, a manufacturer may arrange the Pad points along the X direction of the wafer or along the Y direction of the wafer, that is, the arrangement direction of the Pad points on the wafer is not determined, so as to facilitate matching with the mounting and positioning in the subsequent wafer testing process (it is necessary to ensure that the arrangement direction of the test probe is consistent with the arrangement direction of the Pad on the wafer), and when manufacturing the wafer W, the edge of the wafer W may be provided with a mark notch O.

In this embodiment, in order to ensure that the wafer mounting direction can be adjusted conveniently during testing so that the arrangement direction of Pad points on the wafer can be consistent with the probe testing direction, as shown in fig. 7, as an alternative embodiment, a positioning notch 2122 is further provided at a position corresponding to the concave portion on the inner side of the circular ring body, and a first positioning portion (a position corresponding to the position of the marking notch O in fig. 7) that is positioned in cooperation with the marking notch is provided on the stage; or a second positioning part which is matched with the mark notch for positioning is further arranged on the carrying platform, and the radian between the first positioning part and the second positioning part is 90 degrees. The first positioning part and the second positioning part can be positioning pin holes, and after the Pad point on the wafer is consistent with the probe testing direction, positioning pins are inserted into the mark gaps and the positioning pin holes so as to fix the position of the wafer.

It can be understood that, when the arrangement direction of the Pad points on the wafer is not consistent with the arrangement direction of the probes, for example, the arrangement direction of the Pad points on the wafer is Y direction, the arrangement direction of the probes is X direction, after the marking notch on the wafer is aligned with the first positioning portion and mounted on the stage, the wafer can be rotated by 90 ° in the clockwise direction, and after the marking notch is aligned with the second positioning portion, the wafer is fixedly mounted, and at this time, the direction of the Pad points on the stage is changed into X direction, so that the arrangement direction of the Pad points is consistent with the arrangement direction of the probes, that is, the Pad points are all arranged in X direction on the stage.

In this embodiment, the pincer and the wafer are prevented from being damaged by pressure. As an optional embodiment, the pin card pressing block and the wafer pressing ring are made of materials with hardness smaller than that of the pin card and the wafer, for example, plastic materials are used for manufacturing, and the hardness of the plastic materials is smaller than that of the pin card and that of the wafer, so that the pin card and the wafer can be effectively protected from being crushed.

Referring to fig. 2, in this embodiment, as an alternative embodiment, a transparent window 13 is disposed at the top end of the box body, and a microscope is disposed above the transparent window.

It will be appreciated that fig. 2 shows, as a schematic view, a transparent window as the observation window of the microscope, the microscope being arranged directly above the observation window not being shown. In addition, the Pad of the unit to be tested of the wafer is small (generally 100 micrometers multiplied by 100 micrometers), whether the Pad is aligned with the probe or not can not be directly observed and clear by naked eyes during the test, and the microscope is arranged at the top end of the box body, so that an operator can conveniently move the Pad of the unit to be tested to the lower side of the probe to perform accurate alignment and then perform the probe insertion during the test.

In this embodiment, as an optional embodiment, a vacuum release valve 14 is further disposed on the box body.

It can be appreciated that there is a vacuum inside the cabinet, which is lower than the outside standard air pressure, and the cabinet door is difficult or impossible to open without releasing the internal vacuum. Therefore, through setting up the vacuum release valve, close the vacuum pump after the test is accomplished, open the vacuum release valve, wait that the vacuum in the vacuum box destroys, just can easily open the box door.

Referring to fig. 8, in the present embodiment, as an optional embodiment, a wafer testing method is further provided, including the steps of:

101. opening a box door of the vacuum system;

102. fixedly mounting the wafer on a test board and pushing the wafer into the box body;

103. closing the box body door, and opening a vacuumizing module to vacuumize the box body;

104. and when the vacuum degree in the box body reaches a preset vacuum degree, testing the unit to be tested of the wafer by using a probe installed on the test board.

It should be understood that the wafer testing method provided by this embodiment may be applied to the wafer testing apparatus described in the foregoing embodiments, but is not to be construed as being applicable to only the foregoing wafer testing apparatus.

According to the wafer testing method provided by the embodiment of the invention, a box door of a vacuum system is opened, a wafer is fixedly arranged on a test board, and the wafer is pushed into the box; closing the box body door, and opening a vacuumizing module to vacuumize the box body; and when the vacuum degree in the box body reaches a preset vacuum degree, testing the unit to be tested of the wafer by using a probe installed on the test board. The vacuum environment required by the wafer test is provided, and the method can be used for testing the wafer performance in the vacuum environment.

Further, the step 102 is followed by: and locking the test board, moving the coarse adjustment mechanism and the fine adjustment mechanism under the microscope, and aligning and binding the Pad of the unit to be tested and the probe together.

In order to further disclose the technical solutions of the embodiments of the present invention, the working principles and the effects of the wafer testing apparatus and the components thereof in the embodiments are described as follows:

and opening the front door of the vacuum box body, rotating the fifth adjusting mechanism, adjusting the position of the wafer carrier in the Z-axis direction, and lowering the wafer carrier to the lowest position.

And rotating the first locking mechanism of the test bench anticlockwise to enable the test bench to be in a movable state relative to the box body, and pulling the test bench out of the vacuum box body along the sliding rail on the inner bottom of the box body through the sliding block of the fixed seat 23.

The processed wafer is placed on the wafer carrying platform through the positioning pin arranged on the wafer carrying platform, the wafer is fixedly locked through the wafer pressing ring and then pushed into the vacuum box body, and the first locking mechanism is rotated clockwise, so that the test board is locked and fixed. The wafer specification may be 8 "wafers.

The second locking mechanism, specifically the guide rail clamp of the X-axis and the Y-axis in the figure, is released, and the wafer stage is moved in the X-axis direction and the Y-axis direction by the first adjusting mechanism and the second adjusting mechanism, so as to adjust the position of the wafer stage in the X-axis and the Y-axis. And after the unit to be tested on the wafer is moved to the position right below the transparent observation window through the transparent window, the coarse adjustment of the position of the wafer is completed, and the guide rail clamp of the X axis and the Y axis is locked.

Since the Pad of the unit under test is small (generally 100 μm × 100 μm), it is impossible to directly observe with the naked eye whether the Pad and the probe are in the alignment position corresponding to each other, so that whether the Pad and the probe are aligned can be clearly observed with the aid of the microscope.

Observing through a microscope, rotating the micrometer heads of the third adjusting mechanism, the fourth adjusting mechanism, the fifth adjusting mechanism and the sixth adjusting mechanism, finely adjusting the platform deck in the X axis direction, the Y axis direction, the Z axis direction and the horizontal rotating direction respectively, aligning the Pad of the unit to be measured and the needle points of the needle card one by one, and then rotating the micrometer head of the fifth adjusting mechanism until the micrometer head touches a Z axis limit locking piece, wherein the diagram shows a limit locking ring, so that the Pad of the unit to be measured is reliably contacted with the needle card, and the position correction of the Pad and the probe is completed. In the fine adjustment process of the position of the carrier, the limiting locking ring can avoid damage to the probe due to overlarge deformation of the probe caused by the fact that acting force is possibly applied to the probe due to overlarge movement displacement in the Z-axis direction.

And closing a front door of the vacuum box body, starting the vacuum pump, reading the vacuum degree in the vacuum box body through a vacuum gauge installed on the vacuum box body, testing the wafer unit to be tested when the vacuum degree meets the requirement, and acquiring data, wherein the acquired data can be acquired through an aviation plug interface and stored.

During testing, a plurality of probes in the probe card are used for contacting one unit to be tested on the wafer at one time, so that test data of the unit to be tested can be read at one time, the probe is prevented from being moved for many times for pricking the same unit to be tested, and the test efficiency is improved.

And after the test of one unit to be tested is finished, the vacuum pump is closed, the vacuum release valve is opened, after the vacuum in the vacuum box is broken, the front door is opened, the Z-axis fine adjustment sliding table is rotated to lower the wafer carrying platform to the lowest position, and the test steps are repeated to test the unit to be tested on the wafer in sequence until the test of the wafer is finished.

After the wafer test is finished, a first locking mechanism of the test board, namely the screw shown in the figure, is loosened, the test board is pulled out of the vacuum box body along the slide rail on the inner bottom surface of the box body through the slide block at the bottom of the fixed seat of the test board, and the wafer is replaced.

And after the wafer is replaced, repeating the steps to test another wafer.

It should be noted that, in this document, the emphasis points of the solutions described in the embodiments are different, but there is a certain correlation between the embodiments, and in understanding the solution of the present invention, the embodiments may be referred to each other; in the embodiments of the present application, when a technical feature element is fixed to another technical feature element, the technical feature element may be directly in contact with a surface of the other technical feature element, or an intervening additional technical feature element may be present. Moreover, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The wafer test equipment is characterized by comprising a vacuum system and a test board, wherein the vacuum system comprises a box body and a vacuumizing module connected to the box body, and the test board is arranged in the box body; the vacuum pumping module comprises a vacuum pump, and the test board comprises a carrying platform for placing a wafer and a probe for testing the wafer;

the test board is slidably arranged on the inner bottom surface of the box body;

the test board comprises a fixed seat, a sliding block is arranged at the bottom of the fixed seat, a sliding rail matched with the sliding block is arranged on the inner bottom surface of the box body, and the test board slides on the sliding rail through the sliding block;

the test bench further comprises: the first adjusting mechanism is used for adjusting the position of the carrier in the Y-axis direction, and the second adjusting mechanism is used for adjusting the position of the carrier in the X-axis direction;

the first adjusting mechanism is arranged on the fixed seat, the second adjusting mechanism is arranged on the first adjusting mechanism, and the third adjusting mechanism, the fourth adjusting mechanism, the fifth adjusting mechanism and the sixth adjusting mechanism are arranged on the second adjusting mechanism, wherein the fourth adjusting mechanism is close to the second adjusting mechanism relative to the third adjusting mechanism, the fifth adjusting mechanism is positioned above the fourth adjusting mechanism, the sixth adjusting mechanism is positioned above the fifth adjusting mechanism, and the carrying platform is positioned on the sixth adjusting mechanism;

the sixth adjusting mechanism comprises a platform, the platform deck is arranged on the platform, and a pressure ring for fixing the wafer is arranged on the platform deck; the pressing ring comprises an arc body, and a concave part used for clamping the edge of the wafer is arranged on the lower edge of the inner side of the arc body.

2. The test rig according to claim 1, wherein the test bench further comprises a first locking mechanism for locking the test bench.

3. The test rig of claim 1, wherein the test station further comprises: the first adjusting mechanism is used for adjusting the position of the carrying platform in the Y-axis direction, and the second adjusting mechanism is used for adjusting the position of the carrying platform in the X-axis direction; the X-axis direction and the Y-axis direction are parallel to the bottom surface of the box body;

4. The test equipment as claimed in claim 1 or 3, wherein a first sliding block is arranged at the bottom of the first adjusting mechanism, a first sliding rail matched with the first sliding block is arranged on the upper surface of the fixed seat, and the first adjusting mechanism slides on the first sliding rail through the first sliding block;

5. The test equipment as claimed in claim 1, wherein the third, fourth, fifth and sixth adjusting mechanisms are respectively provided with a sliding platform and a micrometer head arranged on the sliding platform, and the micrometer head drives the sliding platform to slide so as to finely adjust the position of the stage on the X, Y and Z axes and the rotation angle of the stage in the horizontal direction.

6. The test equipment of claim 1 or 3, wherein the first adjusting mechanism and the second adjusting mechanism are respectively provided with a second locking mechanism.

7. The test equipment as claimed in claim 5, wherein a limit lock for limiting the moving position of the stage in the Z-axis direction is provided in the circumferential direction of the micrometer head on the fifth adjusting mechanism.

8. The test equipment as claimed in claim 1, wherein the test bench is further provided with a pin card mounting mechanism, the pin card mounting mechanism comprises a supporting plate, a pin card fixing seat and a pin card pressing block, the supporting plate is vertically arranged on the fixing seat, the pin card fixing seat is mounted on the supporting plate and located above the carrying platform, the pin card fixing seat is provided with a pin card mounting groove, and the pin card pressing block is used for fixing a pin card in the pin card mounting groove.

9. The test apparatus of claim 8, wherein the pincard has a plurality of probes mounted therein.

10. The testing apparatus of claim 1, wherein a transparent window is provided at a top end of the box, and a microscope is provided above the transparent window.

11. The test apparatus as claimed in claim 1, wherein the box body is further provided with a vacuum release valve.

12. A wafer testing method is characterized by comprising the following steps:

opening a box door of the vacuum system;

fixedly mounting the wafer on a test board through a pressure ring, and pushing the wafer into the box body; the compression ring comprises an arc body, and a concave part for clamping the edge of the wafer is arranged on the lower edge of the inner side of the arc body;