Wafer Fixture, Wafer Aging Test Device, and Wafer Aging Test Method

Abstract

This application relates to the field of semiconductor detection technologies, and particularly to a wafer fixture, a wafer aging test device, and a wafer aging test method. The wafer fixture includes: a lower fixture including a wafer carrying portion for carrying a wafer; an upper fixture including a support frame, a circuit board fixed to the lower side of the support frame, and a plurality of probes extending downward, the circuit board having a plurality of through holes; a plurality of zero-point chucks, each including a male head fixed to the support frame and inserted into the through hole and a female head fixed to the lower fixture, and having a locked state in which the male head and the female head are locked and a released state in which the male head and the female head are released; in the locked state, the zero-point chucks pull the upper fixture and the lower fixture tightly against each other, and form a sealed detection space for accommodating the wafer between the upper fixture and the lower fixture, and the probes are conductively in contact with the wafer within the detection space.

Description

Technical Field

[0001] The present application relates to the field of semiconductor testing technologies, and in particular, to a wafer fixture, a wafer aging test device, and a wafer aging test method. Background Art

[0002] After the wafer is manufactured, for example, the wafer can be placed in a wafer fixture for aging tests in a high-pressure and high-temperature environment.

[0003] Related technologies disclose a wafer fixture composed of an upper fixture and a lower fixture. The upper fixture and the lower fixture are detachably connected via a plurality of bolt elements, so as to realize the clamping and unclamping of the fixture. This type of wafer fixture has the problem of inconvenient use, which affects the efficiency of aging tests. Summary of the Invention

[0004] The purpose of the present application is to solve at least one of the above technical problems, and to provide a wafer fixture, a wafer aging test device, and a wafer aging test method.

[0005] In a first aspect, a wafer fixture is provided, including:

[0006] A lower fixture, including a wafer carrying portion for carrying a wafer;

[0007] An upper fixture, including a support frame, a circuit board fixed to the lower side of the support frame, and a plurality of probes extending downward. The circuit board has a plurality of through holes;

[0008] A plurality of zero-point chucks, each including a male head fixed to the support frame and inserted into the through hole and a female head fixed to the lower fixture, and having a locked state in which the male head and the female head are locked and a released state in which the male head and the female head are released;

[0009] In the locked state, the zero-point chuck tightens the upper fixture and the lower fixture against each other, and forms a sealed detection space for accommodating the wafer between the upper fixture and the lower fixture. The probe is electrically conductively in contact with the measurement point of the wafer in the detection space.

[0010] In some possible implementation manners, the upper fixture includes a protection convex ring disposed around the plurality of probes and protruding downward relative to the circuit board. The protection convex ring is directly fixed to the support frame, and the plurality of through holes are arranged in a circumferential direction on the outer peripheral side of the protection convex ring;

[0011] In the locked state, the protection convex ring prevents the circuit board from contacting the lower fixture.

[0012] In some possible embodiments, the plurality of pneumatic chucks are arranged circumferentially on the outer peripheral side of the protective collar.

[0013] In some possible embodiments, the zero-point chuck is a pneumatic chuck and is configured to switch the zero-point chuck from the locked state to the released state by inflating the male head.

[0014] Further comprising:

[0015] A third air passage disposed on the support frame and connected to the male head of each of the zero-point chucks.

[0016] In some possible embodiments, the third air passage includes a fifth air vent joint fixed to the support frame and a plurality of branch air passages branched from the fifth air vent joint, and the plurality of branch air passages are respectively connected to the male heads of the plurality of zero-point chucks.

[0017] In some possible embodiments, the plurality of zero-point chucks are all located outside the detection space.

[0018] In some possible embodiments, further comprising:

[0019] A plurality of suction ports provided on the upper surface of the wafer carrier;

[0020] A first air passage disposed on the lower fixture and connected to the plurality of suction ports for transmitting negative pressure to the plurality of suction ports, thereby sucking and holding the wafer on the wafer carrier;

[0021] A second air passage disposed on the lower fixture and communicating with the detection space for providing a protective gas to the detection space.

[0022] In a second aspect, a wafer aging test device is proposed, including the wafer fixture as described in the first aspect.

[0023] In a third aspect, a wafer aging test method is proposed, and the method is applied to the wafer aging test device as described in the second aspect, including:

[0024] Placing the wafer on the wafer carrier in a manner covering the plurality of suction ports;

[0025] After replacing the air in the plurality of suction ports and the first air passage with a protective gas, evacuating the first air passage to generate a negative pressure at the suction ports to suck and hold the wafer on the wafer carrier;

[0026] In response to the air pressure in the first air passage decreasing to a first set value, controlling the first air passage to close;

[0027] Put the zero-point chuck in the locked state where the upper fixture and the lower fixture are tightened against each other to form a detection space for accommodating the wafer between the upper fixture and the lower fixture;

[0028] After replacing the air in the detection space with a protective gas using the second gas path, continue to fill the sealed chamber with the protective gas via the second gas path until the air pressure in the sealed chamber reaches a second set value, and then control the second gas path to close;

[0029] Heat the wafer carrier to enable the wafer to undergo an aging test in a set temperature environment.

[0030] In some possible embodiments, the first gas path includes a first ventilation joint and a second ventilation joint fixed to the lower fixture, a first section extending from the first ventilation joint to one side of the wafer carrier, and a second section extending from the second ventilation joint to the other side of the wafer carrier. Among them, the first section and the second section are connected in series through the space below the plurality of adsorption ports;

[0031] The second gas path includes a third ventilation joint and a fourth ventilation joint fixed to the lower fixture, a third section extending from the third ventilation joint to the detection space, and a fourth section extending from the fourth ventilation joint to the detection space. Among them, the third section and the fourth section are connected in series through the detection space;

[0032] After replacing the air in the plurality of adsorption ports and the first gas path with a protective gas, evacuate the first gas path to generate a negative pressure at the adsorption ports to adsorb and hold the wafer on the wafer carrier, including:

[0033] Fill the first ventilation joint with the protective gas at a first rate and evacuate the second ventilation joint at a second rate not less than the first rate;

[0034] In response to the oxygen concentration of the gas discharged from the second ventilation joint being below a first set concentration, control the first ventilation joint to close;

[0035] The step of controlling the first gas path to close in response to the air pressure in the first gas path dropping to a first set value includes:

[0036] In response to the air pressure in the first gas path dropping to a first set value, control the second ventilation joint to close;

[0037] The step of continuing to fill the sealed chamber with the protective gas via the second gas path until the air pressure in the sealed chamber reaches a second set value and then controlling the second gas path to close after replacing the air in the detection space with the protective gas using the second gas path includes:

[0038] Fill the third gas vent joint with a protective gas at a third rate and extract gas from the fourth gas vent joint at a fourth rate not greater than the third rate;

[0039] In response to the oxygen concentration of the gas discharged from the fourth gas vent joint being below a second set concentration, control the fourth gas vent joint to close;

[0040] In response to the air pressure in the detection space reaching a second set value, control the third gas vent joint to close.

[0041] According to the wafer chuck provided in this application, the upper chuck and the lower chuck can be quickly clamped together with precise relative positions, quickly separated, and the wafer chuck always has an unchanged zero position, which helps to improve the aging test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description only relate to some embodiments of this application and do not limit this application.

[0043] Figure 1 is an exploded schematic view of a wafer chuck provided in an embodiment of this application.

[0044] Figure 2 is a view observed from another perspective of Figure 1 in which the handling handle and the fifth gas vent joint on the support frame are removed.

[0045] Figure 3 is Figure 2 a schematic view of the wafer chuck shown after being clamped together.

[0046] Figure 4 is Figure 3 a sectional schematic view of

[0047] Figure 5 is Figure 3 another sectional schematic view of

[0048] Figure 6 is Figure 5 an enlarged view of part X1 of

[0049] Figure 7 is a top view of the lower chuck.

[0050] Figure 8 is an exploded schematic view of the upper chuck.

[0051] Figure 9 is a three-dimensional schematic view of the sealing member.

[0052] Figure 10 is Figure 9 a side view of

[0053] Figure 11 is Figure 10 a sectional view of

[0054] Figure 12 is Figure 11 an enlarged view of part X2 of

[0055] Figure 13 a schematic partial sectional view of a sealing member provided in another embodiment of the present application.

[0056] Figure 14 a flowchart of a wafer aging test method provided in an embodiment of the present application.

[0057] Description of reference numerals:

[0058] 100 - lower fixture, 200 - upper fixture, 300 - sealing member;

[0059] 1 - wafer carrying part, 1A - adsorption port, 1B - first air port, 1C - second air port, 1D - first annular groove;

[0060] 2 - first air path;

[0061] 3 - first ventilation joint;

[0062] 4 - second ventilation joint;

[0063] 5 - first section;

[0064] 6 - second section;

[0065] 7 - second air path;

[0066] 8 - third ventilation joint;

[0067] 9 - fourth ventilation joint;

[0068] 10 - third section;

[0069] 11 - fourth section;

[0070] 12 - support frame;

[0071] 13 - circuit board, 13A - through hole;

[0072] 14 - probe;

[0073] 15 - conductive contact;

[0074] 16 - protective convex ring;

[0075] 17 - First Ring, 171 - Outer Ring Body, 172 - Inner Ring Body, 17A - Lower Annular Step Surface, 17B - Upper Annular Step Surface, 17C - Second Ring Groove;

[0076] 18 - Second Ring;

[0077] 19 - Third Ring;

[0078] 20 - Connecting Ring, 20A - Third Ring Groove;

[0079] 21 - Zero Point Chuck;

[0080] 22 - Male Head;

[0081] 23 - Female Head;

[0082] 24 - Sealing Chamber;

[0083] 25 - Fifth Venting Joint. Detailed Implementation Manner

[0084] To make the objectives, technical solutions and advantages of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of this application without creative efforts fall within the scope of protection of this application. It can be understood that, without conflict, some technical means described in the various embodiments herein may be replaced or combined with each other.

[0085] In the description of this application, if there are terms such as "first", "second", etc., they are only used to distinguish the described objects and do not have any sequential or technical meaning. Thus, the objects defined with "first", "second", etc. may explicitly or implicitly include one or more of such objects. Moreover, for example, the term "first element" itself does not imply the existence of a "second element", and the term "second element" itself does not imply the existence of a "first element". In addition, similar terms such as "one" or "a" do not represent a quantity limitation, but rather indicate the existence of at least one, and "multiple" means not less than two.

[0086] In the description of this application, the terms "include" and "have" indicate the existence of the described features, numbers, operations, elements and / or their combinations, but do not exclude the existence or addition of one or more other features, numbers, operations, elements and / or their combinations.

[0087] In the description of the present application, references to "one embodiment" or "some embodiments" etc. mean that in one or more embodiments of the present application, specific features, structures or characteristics described in connection with that embodiment are included. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments" etc. that appear at different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways.

[0088] Figures 1 to 12 A wafer fixture provided by an embodiment of the present application is shown. The wafer fixture can hold a wafer therein and provide a gas protection atmosphere for preventing oxidation, thereby helping a wafer aging test device to complete the aging test of the wafer in a high-temperature environment.

[0089] The wafer fixture mainly includes an upper fixture 200, a lower fixture 100 and a sealing member 300.

[0090] The lower fixture 100 includes a disk-shaped wafer carrying portion 1 (chunk) for carrying the wafer upward. The upper surface of the wafer carrying portion 1 has a plurality of suction ports 1A arranged densely, and a first gas path 2 provided in the lower fixture 100 is connected to these suction ports 1A. When the wafer is placed on the upper surface of the wafer carrying portion 1, the negative pressure can be transmitted to each suction port 1A through the first gas path 2, thereby adsorbing and holding the wafer on the wafer carrying portion 1 to stabilize the test position of the wafer in the wafer fixture.

[0091] The first gas path 2 includes a first ventilation joint 3 and a second ventilation joint 4 fixedly provided on the same side of the lower fixture 100, a first section 5 extending from the first ventilation joint 3 to one side portion of the wafer carrying portion 1, and a second section 6 extending from the second ventilation joint 4 to the other side portion of the wafer carrying portion 1. The first section 5 and the second section 6 are connected in series through the space below the aforementioned plurality of suction ports 1A, and the aforementioned one side portion and the other side portion are opposite on a diameter of the wafer carrying portion 1. In practice, the first ventilation joint 3 and the second ventilation joint 4 can be connected to an external negative pressure source, so as to provide the negative pressure for adsorbing the wafer to the suction ports 1A of the wafer carrying portion 1 through the first gas path 2 by using the negative pressure source.

[0092] The upper surface of the wafer carrying portion 1 also has a first air port 1B and a second air port 1C located on opposite sides of the aforementioned plurality of suction ports 1A, and a second gas path 7 provided in the lower fixture 100 is connected to the first air port 1B and the second air port 1C. In practice, the wafer under test positioned and placed on the wafer carrying portion 1 is located between the first air port 1B and the second air port 1C, that is, the first air port 1B and the second air port 1C are respectively located on opposite sides of the wafer under test. The second gas path 7 is used to provide a protective gas such as nitrogen around the wafer under test.

[0093] The second gas path 7 includes a third vent joint 8 and a fourth vent joint 9 fixedly provided to the lower fixture 100, a third section 10 extending from the third vent joint 8 to the first air port 1B, and a fourth section 11 extending from the fourth vent joint 9 to the second air port 1C. The third section 10 and the fourth section 11 are connected in series and communicated via a sealed chamber 24. Moreover, the third vent joint 8, the fourth vent joint 9, the first vent joint 3, and the second vent joint 4 are arranged side by side on the same side of the lower fixture 100.

[0094] The upper fixture 200 is arranged above the lower fixture 100 in a manner capable of being engaged with the lower fixture 100. The upper fixture 200 includes a support frame 12, a circuit board 13 fixed to the lower side of the support frame 12, a plurality of probes 14 extending downward, and Figure 1 two handling handles shown but not marked in the figure. The support frame 12 can be made of metal, and its structural strength is significantly higher than that of the circuit board 13. The circuit board 13 includes conductive traces (not shown) and a plurality of conductive contacts 15 electrically connected to the aforementioned plurality of probes 14 via the conductive traces. These conductive contacts 15 are arranged on the lower surface of the circuit board 13 and are arranged in four regions at the edge positions of the circuit board 13. The conductive contacts 15 in each region are distributed in a two-dimensional matrix.

[0095] The upper fixture 200 further includes a protective collar 16, which extends around the entire circumference of the periphery of the plurality of probes 14 and protrudes relative to the lower surface of the upper fixture 200. In this way, the protective collar 16 can not only protect the inner probes 14 after the upper fixture 200 is separated from the lower fixture 100, but also, when the upper fixture 200 moves downward and is about to be engaged with the lower fixture 100, keep a reliable safety distance between the upper fixture 200 and the lower fixture 100 by abutting against the upper surface of the lower fixture 100 (more specifically, the upper surface of the wafer carrier portion 1 of the lower fixture 100), that is, prevent the upper fixture 200 from being too close to the lower fixture 100, because their being too close may cause the circuit board 13 to rigidly contact the lower fixture 100 and be damaged, or may cause the contact force between the probes 14 and the wafer to be too large, resulting in damage to the probes 14 and the wafer, such as scratching the wafer.

[0096] The sealing member 300 is arranged around the wafer. When the upper fixture 200 is engaged with the lower fixture 100, the sealing member 300 is squeezed in the vertical direction by the upper fixture 200 and the lower fixture 100, so as to define a sealed chamber 24 for accommodating the wafer with the upper fixture 200 and the lower fixture 100, and the aforementioned first air port 1B and second air port 1C are located in the sealed chamber 24 and are directly communicated with the sealed chamber 24. In this way, a protective gas such as nitrogen can be supplied into the sealed chamber 24 by using the aforementioned second gas path 7, so that the wafer under test is in the atmosphere of the protective gas, preventing the wafer from being oxidized during the high-temperature aging test.

[0097] In this embodiment, the sealing member 300 is fixed to the lower fixture 100. Therefore, when the upper fixture 200 and the lower fixture 100 are separated from each other, the sealing member 300 is separated from the upper fixture 200.

[0098] Please refer to Figure 6 and Figures 9 to 12 , the sealing member 300 includes a first ring 17, a second ring 18, and a third ring 19.

[0099] The first ring 17 is a rigid body detachably fastened to the lower fixture 100 via a probe. In some embodiments, the first ring 17 may be an integrally formed structure molded from a polymer plastic material. Such a first ring 17 has good electrical insulation, so as to avoid contacting electrical components or conductive components on the upper fixture 200 when the upper fixture 200 and the lower fixture 100 are clamped together, thereby affecting the test quality.

[0100] The first ring 17 includes an outer ring body 171 and an inner ring body 172 integrally formed on the inner peripheral side of the outer ring body 171. And at the joint of the inner ring body 172 and the outer ring body 171, a lower annular step surface 17A and an upper annular step surface 17B separated by the inner ring body 172 are formed, and the lower annular step surface 17A and the upper annular step surface 17B define the inner peripheral surface of the outer ring body 171.

[0101] The second ring 18 is a flexible body with a hollow cross-section. It will undergo elastic deformation when stressed and recover the deformation due to its own elastic force when the stress is released. The second ring 18 is disposed below the inner ring body 172 of the first ring 17. And based on the first ring 17 being fastened to the lower fixture 100 by screws, the second ring 18 is clamped between the inner ring body 172 of the first ring 17 and the lower fixture 100 in a deformed state of abutting against the lower annular step surface 17A. The second ring 18 protrudes from the lower surface of the first ring 17 in the natural state without deformation.

[0102] The third ring 19 is disposed above the inner ring body 172 of the first ring 17 and is also a flexible body with a hollow cross-section. It will undergo elastic deformation when stressed and recover the deformation due to its own elastic force when the stress is released. In some embodiments, the third ring 19 may be adhesively fixed to the inner ring body 172 via a high-temperature resistant adhesive to prevent the third ring 19 from detaching from the wafer fixture, especially the lower fixture 100. The cross-sections of the second ring 18 and the third ring 19 in the natural state without deformation are both circular, and the cross-section of the third ring 19 is formed to be larger than that of the second ring 18. The third ring 19 protrudes from the upper surface of the first ring 17 in the natural state.

[0103] When the upper fixture 200 is engaged with the lower fixture 100, the deformed state in which the outer peripheral portion of the third ring 19 abuts against the upper annular step surface 17B and the inner peripheral portion abuts against the outer peripheral surface of the protective convex ring 16 is clamped between the inner ring body 172 and the lower surface of the upper fixture 200, and the protective convex ring 16 contacts the lower fixture 100 in the sealing chamber 24, and the probe 14 contacts the measurement point of the wafer in the sealing chamber 24, so as to transmit test signals between the circuit board 13 and the wafer. During the aging test, a plurality of conductive contacts 15 on the circuit board 13 are used for the external plurality of second probes to be in one-to-one electrical contact, and the second probe is electrically connected to a computer device via a conductive line to transmit the test signal from the wafer to the computer device, so that the computer device analyzes relevant indicators of the wafer based on the test signal.

[0104] In the embodiment of the present application, the area of the circuit board 13 is set to be significantly larger than the area of the lower fixture 100, so that the aforementioned conductive contacts 15 can be arranged at a sufficiently large pitch on the circuit board 13, increasing the pitch between the conductive contacts 15 on the circuit board 13, making it easy for these conductive contacts 15 to contact the aforementioned second probes, and ensuring the stability and safety during the aging test. Therefore, when viewed in the up-down direction, the outer contour of the lower fixture 100 entirely falls within the outer contour of the upper fixture 200, and further, all the conductive contacts 15 are located outside the lower fixture 100. It can be understood that configuring all the conductive contacts 15 on the circuit board 13 to be located outside the lower fixture 100 when viewed in the up-down direction can more easily lead out the test signal from the conductive contacts 15, because the lower fixture 100 does not interfere with the up-down docking of the external second probe and the conductive contacts 15.

[0105] Since the second ring 18 and the third ring 19 are hollow-section rings, they have excellent deformation ability, and after being compressed, they have a relatively large sealing contact area with the first ring 17, the first fixture, and the second fixture. Therefore, the aforementioned sealing chamber 24 with high airtightness can be provided, and further, during the aging test, the sealing chamber 24 can maintain a relatively high and stable protective gas pressure (test pressure), better inhibiting the oxidation of the wafer. In addition, based on the state in which the outer peripheral portion of the third ring 19 abuts against the upper annular step surface 17B and the inner peripheral portion abuts against the outer peripheral surface of the protective convex ring 16, it is clamped between the inner ring body 172 and the upper fixture 200, thus also cleverly using the protective convex ring 16 to further increase the sealing performance at the third ring 19.

[0106] In other embodiments, the protective convex ring 16 can be omitted, and the rigid first ring 17 is directly used to keep a reliable safety distance between the upper fixture 200 and the lower fixture 100, so as to protect the probe 14 and the wafer during clamping. Through such a design, it helps to simplify the structure of the wafer fixture and reduce the manufacturing cost. However, this method compared toFigure 6 The disadvantage of the shown solution is that when the upper fixture 200 is separated from the lower fixture 100, the protection for the probe 14 is reduced.

[0107] Please review Figure 6 , the lower fixture 100 (more specifically, the wafer carrier portion 1) has a first annular groove 1D with an upward opening, the first ring 17 has a second annular groove 17C with a downward opening, and the aforementioned lower annular step surface 17A defines the outer peripheral side wall surface of the second annular groove 17C. The outer peripheral side wall surface of the first annular groove 1D is flush with the outer peripheral side wall surface of the second annular groove 17C, and the inner peripheral side wall surface of the first annular groove 1D is offset from the inner peripheral side wall surface of the second annular groove 17C. More specifically, the inner peripheral side wall surface of the first annular groove 1D is located on the outer peripheral side of the inner peripheral side wall surface of the second annular groove 17C. The second ring 18 is fitted in a deformed state in an annular space with an approximately L-shaped cross-section defined by the first annular groove 1D and the second annular groove 17C. Through such a design, due to the shapes of the first annular groove 1D and the second annular groove 17C, the second ring 18 originally having an annular cross-section will undergo more complex deformation (for example, not a standard elliptical or racetrack-shaped deformation), thereby contributing to obtaining a better sealing effect.

[0108] In some other embodiments, as Figure 13 shown, the sealing member 300 further includes a connecting ring 20, which is also an elastically deformable flexible body and integrally connects the second ring 18 and the third ring 19. The connecting ring 20 defines a third annular groove 20A extending in the entire circumference and opening toward the outer peripheral side, and the inner ring body 172 of the first ring 17 is tightly inserted into the third annular groove 20A. Through such a design, on the one hand, it is possible to prevent the third ring 19 from detaching from the sealing member 300, and even when the sealing member 300 is integrally detached from the wafer fixture, based on the inner ring body 172 being tightly inserted into the third annular groove 20A, the sealing member 300 can still maintain good structural integrity and avoid relevant components such as the third ring 19 from detaching from the sealing member 300. On the other hand, it also helps to enhance the sealing performance of the sealing member 300 for the sealing chamber 24. In particular, it helps to enhance the airtightness between the first ring 17, the second ring 18, and the third ring 19.

[0109] The thickness of the connecting ring 20 can be designed to be appropriately small, so that when observed in the radial direction, the connecting ring 20 is entirely located inside the first ring 17. Through such a design, it is possible to prevent the connecting ring 20 from contacting the upper fixture 200 or the lower fixture 100 and hindering the full deformation of the third ring 19 and the second ring 18.

[0110] The engagement between the upper fixture 200 and the lower fixture 100 is achieved through four zero-point chucks 21. The zero-point chuck 21 includes a mating male head 22 and female head 23, where the male head 22 is disposed on the upper fixture 200 and the female head 23 is disposed on the lower fixture 100. The zero-point chuck 21 has a locked state in which the male head 22 and the female head 23 are locked together and a released state in which the male head 22 and the female head 23 are released. In the locked state, the zero-point chuck 21 tightly engages the upper fixture 200 and the lower fixture 100 together, thereby forming a detection space for accommodating the wafer, namely the aforementioned sealed chamber 24, and the probe 14 contacts the detection points of the wafer within this detection space. In the released state, the locking between the male head 22 and the female head 23 is released, thereby allowing the upper fixture 200 and the lower fixture 100 to separate from each other.

[0111] The zero-point chuck 21 is a pneumatically unlockable pneumatic chuck, which is configured to switch the zero-point chuck 21 from the locked state to the released state by inflating the male head 22 (providing positive pressure), and to keep the zero-point chuck 21 in the locked state by stopping the inflation of the male head 22. Specifically, a third air passage (not shown) provided on the upper fixture 200 is connected to the male heads 22 of these zero-point chucks 21 to inflate these male heads 22 using the third air passage. In the locked state, the third air passage is in a pressureless state, that is, in balance with the ambient atmospheric pressure. The movable member of the male head 22 engages with the female head 23, and the zero-point chuck 21 is in the locked state, preventing the male head 22 and the female head 23 from separating. When the male head 22 is inflated via the third air passage, the movable member of the male head 22 moves under the action of the gas pressure, thereby disengaging from the female head 23 and making the zero-point chuck 21 in the released state. When the inflation of the male head 22 is stopped, that is, when the actuating air pressure is no longer applied to the male head 22, the movable member of the male head 22 returns to the position where it engages with the female head 23 (such as by the force of an elastic biasing member in the male head 22).

[0112] It can be understood that, due to the use of the pneumatic zero-point chuck 21, the upper fixture 200 and the lower fixture 100 can be quickly clamped together with precise relative positions, quickly separated, and the wafer fixture can always have an unchanged zero-point position, thus helping to improve the aging test efficiency.

[0113] The third air passage includes a fifth air connection joint 25 fixedly provided to the upper fixture 200, and four branch air passages (not shown) branch out from the fifth air connection joint 25, and these four branch air passages are respectively connected to the male heads 22 of the four zero-point chucks 21. In this way, by simply inflating one fifth air connection joint 25, the unlocking of the four zero-point chucks 21 can be achieved simultaneously.

[0114] As described above, the area of the upper fixture 200 is significantly larger than that of the lower fixture 100. Therefore, there is a significant difference in the lateral dimensions between the upper fixture 200 and the lower fixture 100, resulting in an unused invalid space formed around the lower fixture 100. This easily leads to a relatively large space occupied by the overall wafer fixture in the aging test cabinet, which is not conducive to the application of the wafer fixture. To effectively utilize the peripheral space of the lower fixture 100 and avoid further increase in the lateral dimension of the upper fixture 200, as Figure 1 shown, the first ventilation joint 3, the second ventilation joint 4, the third ventilation joint 8, and the fourth ventilation joint 9 are installed on one lateral side of the lower fixture 100, and the fifth ventilation joint 25 is installed on the upper side of the upper fixture 200.

[0115] In this embodiment, the circuit board 13 is fixedly stacked on the lower side of the support frame 12 via screws, and the aforementioned protective collar 16 is directly fastened to the support frame 12 via screws (i.e., there is a connection path between the protective collar 16 and the support frame 12 without passing through the circuit board 13). In addition, the male heads 22 of each zero-point chuck 21 are all fixed to the support frame 12. As a result, when the male head 22 of the zero-point chuck 21 is locked with the female head 23 to apply a pulling force that makes the upper fixture 200 and the lower fixture 100 approach each other, the reaction force generated due to the pulling force will not act on the circuit board 13, thus well protecting the circuit board 13. The circuit board 13 has four through holes 13A arranged equidistantly in the circumferential direction on the outer peripheral side of the protective collar 16, and the male heads 22 of the four zero-point chucks 21 are respectively inserted into the through holes 13A to achieve engagement with the female head 23 below.

[0116] Moreover, on the electrical connection path between the probe 14 and the conductive contact 15, there is a wire (not shown) connected to the aforementioned conductive trace on the upper surface side of the circuit board 13. The wire spans the back side of the protective collar 16 on the upper surface side of the circuit board 13 to connect the probe 14 and the conductive trace. By providing the wire, it is possible to easily separate the main body of the circuit board 13, the protective collar 16, and the probe 14, and further, it is possible to easily achieve the direct fixation of the protective collar 16 to the support frame 12.

[0117] The embodiment of the present application also provides a wafer aging test device including the above-mentioned wafer fixture and a method for aging testing a wafer using the wafer aging test device. The method includes:

[0118] S141, placing the wafer on the wafer carrier 1 in a manner that covers a plurality of suction ports 1A.

[0119] In this step S141, the placement angle and position of the wafer on the wafer carrier 1 can be accurately positioned by using a vision system, so that the wafer is placed on the wafer carrier 1 at a specified angular position, so that in subsequent operations, each probe 14 on the upper fixture 200 can accurately contact each measurement point on the wafer. In this step S141, the upper fixture 200 and the lower fixture 100 are not yet clamped together.

[0120] S142. After replacing the air in the adsorption port 1A and the first gas path 2 with a protective gas, air is pumped out of the first gas path 2 to generate a negative pressure at the adsorption port 1A, thereby adsorbing and holding the wafer on the wafer carrier 1.

[0121] This step S142 may specifically include:

[0122] S142a. A protective gas is filled into the first ventilation joint 3 at a first rate, and air is pumped out of the second ventilation joint 4 at a second rate not less than the first rate.

[0123] Since the pumping rate of the second ventilation joint 4 is not less than the filling rate of the first ventilation joint 3, it is possible to avoid generating a positive pressure at the adsorption port 1A and causing an undesired position change of the wafer that has already been positioned.

[0124] During the process of performing this step S142a, an oxygen zirconia oxygen analyzer can be used to detect in real time the oxygen concentration (oxygen content) in the gas discharged from the second ventilation joint 4, thereby monitoring whether the original gas (i.e., air containing oxygen) in the adsorption port 1A and the first gas path 2 has been exhausted. Additionally, the protective gas can be high-purity nitrogen.

[0125] S142b. In response to the oxygen concentration of the gas discharged from the second ventilation joint 4 being below a set concentration (for example, 200 PPM), the first ventilation joint 3 is controlled to close. Since air continues to be pumped out of the second ventilation joint 4, a negative pressure is generated at each adsorption port 1A to adsorb and hold the wafer on the wafer carrier 1.

[0126] S143. In response to the air pressure at the second ventilation joint 4 decreasing to a first set value, the second ventilation joint 4 is controlled to close. That is, when the air pressure in the first gas path 2 decreases to the first set value, the first gas path 2 is closed.

[0127] At this time, based on the fact that both the first ventilation joint 3 and the second ventilation joint 4 are in a closed state, and each adsorption port 1A of the wafer carrier 1 is covered by the wafer, a negative pressure closed space defined by the wafer, the adsorption port 1A, and the first gas path 1 is formed, and the oxygen content of the gas in this negative pressure closed space is extremely small. Therefore, in subsequent high-temperature aging tests, oxidation of the lower surface portion of the wafer can be effectively inhibited.

[0128] S144. Engage the upper fixture 200 with the lower fixture 100 to form the aforementioned sealed chamber 24, completing the clamping. Specifically, with the male heads 22 and female heads 23 of the four zero-point chucks 21 aligned, control the upper fixture 200 to move closer to the lower fixture 100 to a set position, thereby locking the male heads 22 and female heads 23 together.

[0129] At this time, the sealed chamber 24 for accommodating the wafer is formed, and the multiple probes 14 provided on the upper fixture 200 contact the respective measurement points of the wafer downward. Therefore, the probes 14 provide a certain pressing force towards the wafer carrier 1 to the wafer under test, and this pressing force helps the wafer to be maintained in a stable test position.

[0130] In this embodiment, the four zero-point chucks 21 are all arranged outside the sealed chamber 24 rather than inside the sealed chamber 24. With such a design, on the one hand, it helps to simplify the structure of the wafer fixture, and on the other hand, it can prevent the gas filled into the male heads 22 from accidentally entering the sealed chamber 24 during the operation and destroying the low-oxygen atmosphere in the sealed chamber 24. And thus, the gas used to control the locking and releasing of the zero-point chucks 21 does not need to use a dedicated protective gas, but air can be used, which helps to save the usage cost of the fixture.

[0131] S145. After replacing the air in the sealed chamber 24 with a protective gas, continue to fill the sealed chamber 24 with the protective gas until the air pressure in the sealed chamber 24 rises to a second set value.

[0132] In this embodiment, this step S145 may specifically include:

[0133] S145a. Fill the third ventilation joint 8 with the protective gas at a third rate and extract gas from the fourth ventilation joint 9 at a fourth rate that is not greater than (e.g., less than) the third rate.

[0134] Since the gas extraction rate from the third ventilation joint 8 is not greater than the gas filling rate of the fourth ventilation joint 9, it is possible to avoid generating a negative pressure relative to the adsorption port 1A in the sealed chamber 24 and causing an undesired position change of the already positioned wafer. It can be understood that the protective gas filled from the third ventilation joint 8 enters the sealed chamber 24 through the third section 10 and the first air port 1B of the second gas path 7, thereby pushing the air originally in the sealed chamber 24 out through the second air port 1C, the fourth section 11 of the second gas path 7, and the fourth ventilation joint 9. As this action continues, the proportion of the protective gas in the sealed chamber 24 becomes higher and higher, and the proportion of air becomes lower and lower, and the air in the sealed chamber 24 is replaced with the protective gas.

[0135] During the process of performing step S145a, an oxygen zirconia oxygen analyzer can be used to detect in real time the oxygen concentration in the gas discharged from the fourth vent joint 9, thereby monitoring whether the original gas (i.e., air) in the sealed chamber 24 has been exhausted. Additionally, the protective gas in step S146 can also be high-purity nitrogen.

[0136] S145b, in response to the oxygen concentration in the gas discharged from the fourth vent joint 9 being below a set concentration (e.g., 200 PPM), control the fourth vent joint 9 to close. Since inflation continues to the third vent joint 8, a positive pressure is generated within the sealed chamber 24.

[0137] S145c, in response to the air pressure in the sealed chamber 24 reaching a second set value (e.g., 0.6 Mpa), control the third vent joint 8 to close.

[0138] S146, heat the wafer carrier 1 so that the wafer undergoes an aging test in a set temperature environment.

[0139] In some embodiments, the wafer carrier 1 is heated by a heating plate that abuts against the lower side of the wafer carrier 1, so that on the one hand, heat is conducted through the wafer carrier 1 to the lower surface of the wafer, and on the other hand, heat is transferred through the wafer carrier 1 to the high-pressure protective gas within the sealed chamber 24, and then conducted by the high-pressure protective gas to the upper surface of the wafer and the probe 14, so that the wafer under test is surrounded by a controlled high-temperature environment as a whole and undergoes an aging test. In this way, the wafer is heated and undergoes an aging test in a high-pressure environment protected by the protective gas. Additionally, it can be understood that during the process of performing this aging test, even if the air pressure in the adsorption port 1A may increase due to temperature rise, resulting in a decrease in its adsorption force, the similarly heated high-pressure gas within the sealed chamber 24 will help press the wafer against the wafer carrier 1, and the probe 14 that contacts and presses the wafer downward will also help press the wafer against the wafer carrier 1, thereby well stabilizing the position of the wafer relative to the wafer carrier 1 and the probe 14, avoiding relative displacement between the probe 14 and the wafer. Therefore, the aforementioned first set value for initially maintaining the position of the wafer does not need to be too small.

Claims

1. A wafer clamp, characterized in that: include: A lower fixture, comprising a wafer carrying portion for carrying a wafer; An upper fixture comprises a support frame, a circuit board fixed to the lower side of the support frame, a plurality of probes extending downward, and a protective convex ring arranged at the periphery of the plurality of probes and protruding downward relative to the circuit board, wherein the protective convex ring is directly fixed to the support frame without passing through the circuit board, the circuit board having a plurality of through holes arranged in a circumferential direction on the outer peripheral side of the protective convex ring and a plurality of conductive contacts located on the outer peripheral side of the plurality of through holes, the plurality of conductive contacts being arranged in four regions at the edge position of the circuit board, and the conductive contacts being used to electrically contact an external second probe; The electrical connection paths between the plurality of probes and the conductive contacts include a wire conductor that crosses the back side of the protective convex ring on the upper surface side of the circuit board; A plurality of zero-point chucks, each comprising a male head fixed to the support frame and inserted into the through hole and a female head fixed to the lower clamp, and having a locking state in which the male head is locked with the female head and a releasing state in which the male head is released from the female head; A sealing member, comprising a first ring which is a rigid body, a second ring which is a flexible body with a hollow cross section and is elastically deformable, and a third ring which is a flexible body with a hollow cross section and is elastically deformable, wherein the first ring comprises an outer ring body and an inner ring body which is integrally formed on the inner circumference of the outer ring body, a lower annular step surface and an upper annular step surface which are separated by the inner ring body are formed at the junction of the inner ring body and the outer ring body, the second ring is arranged at the lower part of the inner ring body of the first ring, and the third ring is arranged at the upper part of the inner ring body of the first ring; In the locked state, the zero-point chuck pulls the upper clamp and the lower clamp together and forms a sealed detection space for accommodating the wafer between the upper clamp, the sealing member and the lower clamp. The third ring is clamped between the inner ring body and the upper clamp in a deformed state with its outer circumference abutting against the upper annular step surface and its inner circumference abutting against the outer circumference of the protective convex ring. The multiple probes can conductively contact the test points of the wafer in the detection space, and the protective convex ring prevents the circuit board from contacting the lower clamp.

2. The wafer clamp according to claim 1, characterized in that: The plurality of zero-point chucks are arranged along the circumferential direction on the outer peripheral side of the protective convex ring.

3. The wafer clamp according to claim 1, characterized in that: The zero-point chuck is a pneumatic chuck and is configured to switch the zero-point chuck from the locked state to the released state by inflating air into the male head; Also includes: A third gas path is disposed on the support frame and connected to the male head of each zero-point chuck.

4. The wafer clamp according to claim 3, characterized in that: The third air circuit includes a fifth air joint fixed to the support frame and a plurality of branch air circuits branching from the fifth air joint, and the plurality of branch air circuits are respectively connected to the male connectors of the plurality of zero-point chucks.

5. The wafer clamp according to claim 3, characterized in that: The multiple zero-point chucks are all located outside the detection space.

6. The wafer chuck according to any one of claims 1 to 5, characterized in that: Also includes: A plurality of suction ports are arranged on the upper surface of the wafer supporting portion; a first gas path, disposed on the lower fixture and connected to the plurality of suction ports, for transmitting negative pressure to the plurality of suction ports, thereby adsorbing and holding the wafer on the wafer supporting portion; The second gas path is arranged on the lower fixture and connected to the detection space, and is used for providing protective gas to the detection space.

7. A wafer aging test device, characterized in that: Comprising the wafer chuck as claimed in claim 6.

8. A wafer aging test method, characterized in that: The method is applied to the wafer aging test device according to claim 7, comprising: Placing a wafer on the wafer supporting portion in a manner of covering the plurality of suction ports; After replacing the air in the plurality of suction ports and the first gas path with protective gas, exhausting air into the first gas path to generate negative pressure at the suction ports to suction and hold the wafer on the wafer supporting portion; In response to the air pressure of the first air circuit decreasing to a first set value, controlling the first air circuit to close; The zero-point chuck is placed in the locked state where the upper clamp and the lower clamp are pulled tight against each other, so as to form a detection space for accommodating the wafer between the upper clamp and the lower clamp; After replacing the air in the detection space with protective gas by using the second gas path, the protective gas is continuously charged into the detection space through the second gas path until the gas pressure in the detection space reaches a second set value, and the second gas path is controlled to be closed; The wafer carrying part is heated so that the wafer undergoes an aging test in a set temperature environment.

9. The method according to claim 8, characterized in that The first air path includes a first ventilation joint and a second ventilation joint fixed to the lower fixture, a first section extending from the first ventilation joint to one side of the wafer supporting part, and a second section extending from the second ventilation joint to the other side of the wafer supporting part, wherein the first section and the second section are connected in series via a space below the plurality of suction ports; The second air path includes a third ventilation joint and a fourth ventilation joint fixed to the lower fixture, a third section extending from the third ventilation joint to the detection space, and a fourth section extending from the fourth ventilation joint to the detection space, wherein the third section and the fourth section are connected in series via the detection space; After replacing the air in the plurality of suction ports and the first gas path with the protective gas, exhausting the air into the first gas path to generate a negative pressure at the suction port to suction and hold the wafer on the wafer supporting part, comprises: Filling the first vent joint with protective gas at a first rate, and extracting gas from the second vent joint at a second rate not less than the first rate; In response to the oxygen concentration of the gas exhausted from the second vent joint being below a first set concentration, controlling the first vent joint to close; In response to the air pressure of the first air path decreasing to a first set value, controlling the first air path to be closed comprises: In response to the air pressure of the first air circuit decreasing to a first set value, controlling the second ventilation joint to close; After replacing the air in the detection space with the protective gas by the second gas path, the protective gas is continuously charged into the detection space through the second gas path until the gas pressure in the detection space reaches a second set value, and the second gas path is controlled to be closed, including: Filling the third vent joint with protective gas at a third rate, and extracting gas from the fourth vent joint at a fourth rate not greater than the third rate; In response to the oxygen concentration of the gas exhausted from the fourth vent joint being below a second set concentration, controlling the fourth vent joint to close; In response to the air pressure in the detection space reaching a second set value, the third ventilation joint is controlled to be closed.

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